Initial dump

.gitignore

@@ -0,0 +1 @@
+.luarepl-history

README.md

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+# Ray-Casting Learning
+
+This repository holds my learning of implementing ray-casting in Love2D using
+Fennel. I hope also to implement a similar technique in the TIC-80, also using
+Fennel; I suspect much of the code will be replicated.
+
+This learning depends primarily on the work of Lode ([Raycasting
+Tutorial](https://lodev.org/cgtutor/raycasting.html)), and supplemented by
+wojciech-graj and their [Wolf-80](https://github.com/wojciech-graj/Wolf-80)
+project.
+
+This project was started with the
+[min-love2d-fennel](https://gitlab.com/alexjgriffith/min-love2d-fennel) project
+authored by Alex Griffith.
+
+A huge thank you to all aforementioned. You have made my learning possible, and
+my exploration into game-dev and Fennel/Love2D much more accessible and
+enjoyable!

buildtools/appimage/build.sh

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+#!/bin/bash
+
+set -eo >/dev/null
+
+CURRENT_APPIMAGEKIT_RELEASE=9
+ARCH="$(uname -m)"
+
+if [[ $# -lt 1 ]]; then
+        echo "Usage: $0 <version>"
+        exit 0
+fi
+
+VERSION="$1"
+LOVEFILE="$2"
+USERNAME=$3
+TOKEN=$4
+
+# https://github.com/love2d/love/releases/download/11.5/love-11.5-x86_64.AppImage
+# https://github.com/love2d/love/releases/download/11.4/love-11.4-x86_64.AppImage
+# https://github.com/love2d/love/releases/download/11.3/love-11.3-x86_64.AppImage
+# https://github.com/love2d/love/releases/download/11.2/love-11.2-x86_64.AppImage
+# https://github.com/love2d/love/releases/download/11.1/love-11.1-linux-x86_64.AppImage
+LOVE_AppImage_URL=https://github.com/love2d/love/releases/download/${VERSION}/love-${VERSION}-${ARCH}.AppImage
+if [ $VERSION == "11.1" ]
+then
+    LOVE_AppImage_URL=https://github.com/love2d/love/releases/download/${VERSION}/love-${VERSION}-linux-${ARCH}.AppImage
+fi
+CACHE_DIR=${HOME}/.cache/love-release/love
+LOVE_AppImage=$CACHE_DIR/love-${VERSION}-${ARCH}.AppImage
+
+if ! test -d ${CACHE_DIR}; then
+    mkdir -p ${CACHE_DIR}
+fi
+
+get-development-artifact(){
+    owner=love2d
+    repo=love
+    branch="12.0-development"
+    artifact="love-x86_64.AppImage" # love-windows-x64 love-macos
+    token=$2
+    username=$1
+    list_run_url="https://api.github.com/repos/${owner}/${repo}/actions/runs"
+    echo "find latest run of branch 12.0"
+    latest_run=$(curl -v --silent \
+                      -H "Accept: application/vnd.github.v3+json" \
+                      -H "Authorization token ${token}" "${list_run_url}" \
+                      --stderr -  |\
+                     grep -B 4 "\"head_branch\": \"12.0-development\"" |\
+                     grep "id" |\
+                     head -1 |\
+                     sed 's/^.* \(.*\),$/\1/g')
+    list_artifacts_url="https://api.github.com/repos/${owner}/${repo}/actions/runs/${latest_run}/artifacts"
+    echo "get artifact_url"
+    artifact_url=$(curl --silent \
+                        -H "Accept: application/vnd.github.v3+json" \
+                        -H "Authorization token ${token}" \
+                        "${list_artifacts_url}" \
+                        --stderr - |\
+                       grep -A 5 "\"name\": \"${artifact}\"," |\
+                       grep "archive_download_url" |\
+                       head -1 |\
+                       sed 's/^.* \"\(.*\)\",$/\1/g')
+    echo "download target"
+    echo curl -L -u ${username}:${token} ${artifact_url} -o love.zip
+    echo $(pwd)
+    rm -f love.zip love-*.AppImage && \
+        curl -L -u ${username}:${token} ${artifact_url} -o love.zip \
+        && unzip love.zip && \
+        rm -f love.zip ${artifact} && \
+        mv love-*.AppImage ${artifact}
+}
+
+if ! test -f ${LOVE_AppImage}; then
+    if [ $VERSION != "12.0" ]
+    then
+        curl -L -C - -o ${LOVE_AppImage} ${LOVE_AppImage_URL}
+    else
+        get-development-artifact $USERNAME $TOKEN
+        mv love-x86_64.AppImage ${LOVE_AppImage}
+    fi
+    chmod +x ${LOVE_AppImage}
+fi
+
+echo $CACHE_DIR
+
+if ! test -f ${LOVE_AppImage}; then
+    echo "No tarball found for $VERSION in $LOVE_AppImage"
+    exit 1
+fi
+
+download_if_needed() {
+        if ! test -f "$1"; then
+                if ! curl -L -o "$1" "https://github.com/AppImage/AppImageKit/releases/download/${CURRENT_APPIMAGEKIT_RELEASE}/$1"; then
+                        echo "Failed to download appimagetool"
+                        echo "Please supply it manually"
+                        exit 1
+                fi
+                chmod +x "$1"
+        fi
+}
+
+main() {
+        download_if_needed appimagetool-${ARCH}.AppImage    
+        # Extract the tarball build into a folder
+        rm -rf love-prepared
+        mkdir -p love-prepared
+        cd love-prepared
+        $LOVE_AppImage --appimage-extract 1> /dev/null 2> /dev/null
+        mv squashfs-root/* .
+        rm squashfs-root/.DirIcon
+        rmdir squashfs-root
+        # Add our small wrapper script (yay, more wrappers), and AppRun
+        local desktopfile="love.desktop"
+        local icon="love"
+        local target="love-${VERSION}"
+
+        if test -f ../../game.desktop.in; then
+                desktopfile="game.desktop"
+                cp ../../game.desktop.in .
+        fi
+        if test -f ../../game.svg; then
+                icon="game"
+                cp ../../game.svg .
+        fi
+        if test -f ${LOVEFILE}; then
+                if [[ $VERSION == "11.4" || $VERSION == "11.5" || $VERSION == "12.0" ]]
+                then
+                    dir="bin"
+                else
+                    dir="usr/bin"
+                fi                
+                target="game"
+                cat $dir/love ${LOVEFILE} > $dir/love-fused
+                mv $dir/love-fused $dir/love
+                chmod +x $dir/love
+    else
+                echo "Love file ${LOVEFILE} not found"
+        fi
+
+        # Add our desktop file
+        mv ${desktopfile} ${desktopfile}.in
+        sed -e "s/%ICON%/${icon}/" "${desktopfile}.in" > "$desktopfile"
+        rm "${desktopfile}.in"
+
+        # Add a DirIcon
+        cp "${icon}.svg" .DirIcon
+
+        # Clean up
+        if test -f ../../game.desktop.in; then
+                rm love.desktop.in
+        fi
+        if test -f ../../game.svg; then
+                rm love.svg
+        fi
+
+        # Now build the final AppImage
+        cd ..
+
+        # ./love-prepared/AppRun -n love-prepared "${target}-${ARCH}.AppImage"
+        # Work around missing FUSE/docker
+        ./appimagetool-${ARCH}.AppImage --appimage-extract 1> /dev/null 2> /dev/null
+        ./squashfs-root/AppRun -n love-prepared "${target}-${ARCH}.AppImage" 1> /dev/null 2> /dev/null
+        ## rm -rf love-prepared/
+}
+
+main "$@"

buildtools/love-js/love-js.sh

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+#!/bin/bash
+
+help="love-js.sh: \n
+    A tool for assembling love.js projects without relying on npm / node. \n\
+    For the full project please see https://github.com/Davidobot/love.js \n\
+\n\
+usage: \n\
+    ./love-js.sh [love-file] [project-name] [opts]\n\
+\n
+opts:\n
+  -v= (--version=) Version of the Game. Will be included in file name.\n
+  -o= (--output-directory=) Target directory. Defaults to PWD\n
+  -t= (--text-colour=) Text Colour. Defaults to \"240,234,214\"\n
+  -c= (--canvas-colour=) Canvas Colour. Defaults to \"54,69,79\"\n
+  -a= (--author=) Author (Shows up on loading page).\n
+  -w= (--width=) Canvas Width (game width in conf). Defaults to 800\n
+  -h= (--height=) Canvas Height (game height in conf). Defaults to 600\n
+  -r  (--run) Set flag if you want to run a local copy on port 8000\n
+  -d  (--debug) Set flag for debug info\n
+  -h  (--help) Display this text\n
+\n
+eg: \n\
+
+Pack up sample.love\n
+\t./love-js.sh sample.love sample\n
+\t> sample-web.zip\n
+\n
+Pack up sample.love version 0.1.0\n
+\t./love-js.sh sample-0.1.0.love sample -v=0.1.0\n
+\t> sample-0.1.0-web.zip\n
+\n
+Pack up sample.love and set the background colour to black\n
+\t./love-js.sh sample-0.1.0.love sample -v=0.1.0 -c=\"0,0,0\"\n
+\t> sample-0.1.0-web.zip\n
+\n
+Pack up sample.love and set the author to \"Sample Name\"\n
+\t./love-js.sh sample-0.1.0.love sample -a=\"Sample Name\"\n
+\t> sample-web.zip"
+
+if [ "$#" -lt  "2" ]
+  then
+      echo "ERROR! love-js.sh expects at least two arguments."
+      echo -e $help
+      exit 1
+fi
+
+# use gdu on macOS, fixes 'invalid option -b' error
+if [ "$(uname -s)" = "Darwin" ]; then
+  DU_CMD=gdu
+else
+ DU_CMD=du
+fi
+
+love_file=$1
+name=$2
+## confirm that $release_dir/$name-$version.love exists
+if [ ! -f $love_file ]; then
+    echo "love file not found!"
+    echo $love_file
+    exit 1
+fi
+
+if [ -f /proc/sys/kernel/random/uuid ]; then
+   uuid=$(cat /proc/sys/kernel/random/uuid)
+else
+    uuid="2fd99e56-5455-45dd-86dd-7af724874d65"
+fi
+
+author="";
+run=false;
+debug=false;
+gethelp=false;
+width=800
+height=600
+release="compat"
+love_version="11.5"
+canvas_colour="54,69,79"
+text_colour="240,234,214"
+initial_memory=0
+module_size=$($DU_CMD -b $love_file | awk '{print $1}')
+title=$(echo $name | sed -r 's/\<./\U&/g' | sed -r 's/-/\ /g')
+version=""
+dash_version=""
+output_dir=$(pwd)
+cachemodule="true"
+
+for i in "$@"
+do
+case $i in
+    -v=*|--version=*)
+    version="${i#*=}"
+    dash_version="-${i#*=}"
+    ;;
+    -o=*|--output-directory=*)
+    output_dir="${i#*=}"
+    ;;
+    -w=*|--width=*)
+    width="${i#*=}"
+    ;;    
+    -h=*|--height=*)
+    height="${i#*=}"
+    ;;
+    -t=*|--text-colour=*)
+    text_colour="${i#*=}"
+    ;;
+    -c=*|--canvas-colour=*)
+    canvas_colour="${i#*=}"
+    ;;
+    -a=*|--author=*)
+    author="${i#*=}"
+    ;;        
+    -r|--run)
+    run=true
+    ;;
+    -d|--debug)
+    debug=true
+    ;;
+    -h|--help)
+    gethelp=true
+    ;;
+    -n|--no-cache)
+    cachemodule="false"
+    ;;    
+    *)
+            # unknown option
+    ;;
+esac
+done
+
+page_colour=$canvas_colour
+
+file_name=$output_dir/$name$dash_version-web
+
+debug (){
+    if [ $debug = true ]
+    then
+        echo ""
+        echo "Debug:         love-js.sh"
+        echo "love file:     ${love_file}"
+        echo "output file:   $file_name"
+        echo "author:        $author"
+        echo "version:       $version"
+        echo "text colour:   $text_colour"
+        echo "canvas colour: $canvas_colour"
+        echo "canvas size:   ${height}, ${width}"
+        echo "run:           ${run}"
+        echo "use cache:     $cachemodule"
+    fi
+}
+
+call_dir=$(pwd)
+root="$(dirname "$0")"
+
+build(){
+    rm -fr $file_name
+    mkdir -p $file_name && mkdir -p $file_name/theme
+
+    cat $root/src/index.html | \
+        sed "s/{{title}}/${title}/g" | \
+        sed "s/{{version}}/${version}/g" | \
+        sed "s/{{author}}/${author}/g" | \
+        sed "s/{{width}}/${width}/g" | \
+        sed "s/{{height}}/${height}/g" | \
+        sed "s/{{initial-memory}}/${initial_memory}/g" | \
+        sed "s/{{canvas-colour}}/${canvas_colour}/g" | \
+        sed "s/{{text-colour}}/${text_colour}/g" > \
+            $file_name/index.html
+    
+    cat $root/src/love.css | \
+        sed "s/{{page-colour}}/${page_colour}/g" > \
+            $file_name/theme/love.css
+    
+    cat $root/src/game.js | \
+        sed "s/{{{cachemodule}}}/${cachemodule}/g" | \
+        sed "s/{{{metadata}}}/{\"package_uuid\":\"${uuid}\",\"remote_package_size\":$module_size,\"files\":[{\"filename\":\"\/game.love\",\"crunched\":0,\"start\":0,\"end\":$module_size,\"audio\":false}]}/" > \
+            $file_name/game.js
+    cp $root/src/serve.py $file_name
+    cp $root/src/consolewrapper.js $file_name
+    cp $love_file $file_name/game.love
+    cp $root/src/love-$love_version/$release/love.js $file_name
+    cp $root/src/love-$love_version/$release/love.wasm $file_name
+    if [ $release == "release" ]; then
+        cp $root/src/release/love.worker.js $file_name
+    fi
+}
+
+clean(){
+    rm -rf $file_name
+}
+
+release (){
+    rm -fr $file_name
+    build
+    debug
+    zip -r -q tmp $file_name
+    rm -f $file_name.zip
+    mv tmp.zip $file_name.zip
+    clean
+}
+
+run (){
+    debug
+    build
+    cd $file_name
+    python3 serve.py
+}
+
+if [ $gethelp = true ]
+then
+    echo -e $help
+elif [ $run = false ]
+then
+    release
+else
+    run
+fi

buildtools/love-js/src/consolewrapper.js

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+var newConsole = (function(oldConsole)
+{
+    return {
+        log : function()
+        {
+            var data = [];
+            for (var _i = 0; _i < arguments.length; _i++) {
+                data[_i] = arguments[_i];
+            }
+            if(data.length == 1) //Start looking for api's (And dont show anything)
+            {
+                if(typeof(data[0]) == "string" && data[0].indexOf("callJavascriptFunction") != -1) //Contains function
+                {
+                    // oldConsole.log(data[0]);
+                    try
+                    {
+                        return eval(data[0].split("callJavascriptFunction ")[1]);
+                    }
+                    catch(e)
+                    {
+                        oldConsole.error("Something went wrong with your callJS: \nCode: " + data[0].split("callJavascriptFunction ")[1] + "\nError: '" + e.message + "'");
+                        return null;
+                    }
+                }
+                else
+                {
+                    oldConsole.log(data[0]);
+                    return null;
+                }
+            }
+            else
+                oldConsole.log(data[0], data.splice(1));
+            return null;
+        },
+        warn : function()
+        {
+            var data = [];
+            for (var _i = 0; _i < arguments.length; _i++) {
+                data[_i] = arguments[_i];
+            }
+            if(data.length == 1)
+                oldConsole.warn(data[0]);
+            else
+                oldConsole.warn(data[0], data.splice(1));
+        },
+        error : function()
+        {
+            var data = [];
+            for (var _i = 0; _i < arguments.length; _i++) {
+                data[_i] = arguments[_i];
+            }
+            if(data.length == 1)
+                oldConsole.error(data[0]);
+            else
+                oldConsole.error(data[0], data.splice(1));
+        },
+        info : function()
+        {
+            var data = [];
+            for (var _i = 0; _i < arguments.length; _i++) {
+                data[_i] = arguments[_i];
+            }
+            if(data.length == 1)
+                oldConsole.info(data[0]);
+            else
+                oldConsole.info(data[0], data.splice(1));
+        },
+        clear : function()
+        {
+            oldConsole.clear()
+        },
+        assert : function()
+        {
+            for (var _i = 0; _i < arguments.length; _i++) {
+                data[_i] = arguments[_i];
+            }
+            oldConsole.assert(data[0], data[1], data.splice(2));
+        },
+        group : function()
+        {
+            for (var _i = 0; _i < arguments.length; _i++) {
+                data[_i] = arguments[_i];
+            }
+            oldConsole.group(data[0], data.splice(1));
+        },
+        groupCollapsed : function()
+        {
+            for (var _i = 0; _i < arguments.length; _i++) {
+                data[_i] = arguments[_i];
+            }
+            oldConsole.groupCollapsed(data[0], data.splice(1));
+        },
+        groupEnd : function()
+        {
+            oldConsole.groupEnd()
+        }
+    }
+}(window.console));
+window.console = newConsole;

buildtools/love-js/src/game.js

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+var Module;
+
+var CACHEMODULE = {{{cachemodule}}};
+
+if (typeof Module === 'undefined') Module = eval('(function() { try { return Module || {} } catch(e) { return {} } })()');
+
+if (!Module.expectedDataFileDownloads) {
+  Module.expectedDataFileDownloads = 0;
+  Module.finishedDataFileDownloads = 0;
+}
+Module.expectedDataFileDownloads++;
+(function() {
+ var loadPackage = function(metadata) {
+
+  var PACKAGE_PATH;
+  if (typeof window === 'object') {
+    PACKAGE_PATH = window['encodeURIComponent'](window.location.pathname.toString().substring(0, window.location.pathname.toString().lastIndexOf('/')) + '/');
+  } else if (typeof location !== 'undefined') {
+      // worker
+      PACKAGE_PATH = encodeURIComponent(location.pathname.toString().substring(0, location.pathname.toString().lastIndexOf('/')) + '/');
+    } else {
+      throw 'using preloaded data can only be done on a web page or in a web worker';
+    }
+    var PACKAGE_NAME = 'game.love';
+    var REMOTE_PACKAGE_BASE = 'game.love';
+    if (typeof Module['locateFilePackage'] === 'function' && !Module['locateFile']) {
+      Module['locateFile'] = Module['locateFilePackage'];
+      Module.printErr('warning: you defined Module.locateFilePackage, that has been renamed to Module.locateFile (using your locateFilePackage for now)');
+    }
+    var REMOTE_PACKAGE_NAME = typeof Module['locateFile'] === 'function' ?
+    Module['locateFile'](REMOTE_PACKAGE_BASE) :
+    ((Module['filePackagePrefixURL'] || '') + REMOTE_PACKAGE_BASE);
+
+    var REMOTE_PACKAGE_SIZE = metadata.remote_package_size;
+    var PACKAGE_UUID = metadata.package_uuid;
+
+    function fetchRemotePackage(packageName, packageSize, callback, errback) {
+      var xhr = new XMLHttpRequest();
+      xhr.open('GET', packageName, true);
+      xhr.responseType = 'arraybuffer';
+      xhr.onprogress = function(event) {
+        var url = packageName;
+        var size = packageSize;
+        if (event.total) size = event.total;
+        if (event.loaded) {
+          if (!xhr.addedTotal) {
+            xhr.addedTotal = true;
+            if (!Module.dataFileDownloads) Module.dataFileDownloads = {};
+            Module.dataFileDownloads[url] = {
+              loaded: event.loaded,
+              total: size
+            };
+          } else {
+            Module.dataFileDownloads[url].loaded = event.loaded;
+          }
+          var total = 0;
+          var loaded = 0;
+          var num = 0;
+          for (var download in Module.dataFileDownloads) {
+            var data = Module.dataFileDownloads[download];
+            total += data.total;
+            loaded += data.loaded;
+            num++;
+          }
+          total = Math.ceil(total * Module.expectedDataFileDownloads/num);
+          if (Module['setStatus']) Module['setStatus']('Downloading data... (' + loaded + '/' + total + ')');
+        } else if (!Module.dataFileDownloads) {
+          if (Module['setStatus']) Module['setStatus']('Downloading data...');
+        }
+      };
+      xhr.onerror = function(event) {
+        throw new Error("NetworkError for: " + packageName);
+      }
+      xhr.onload = function(event) {
+        if (xhr.status == 200 || xhr.status == 304 || xhr.status == 206 || (xhr.status == 0 && xhr.response)) { // file URLs can return 0
+          var packageData = xhr.response;
+          callback(packageData);
+        } else {
+          throw new Error(xhr.statusText + " : " + xhr.responseURL);
+        }
+      };
+      xhr.send(null);
+    };
+
+    function handleError(error) {
+      console.error('package error:', error);
+    };
+
+    function runWithFS() {
+
+      function assert(check, msg) {
+        if (!check) throw msg + new Error().stack;
+      }
+      // {{{create_file_paths}}}
+
+      function DataRequest(start, end, crunched, audio) {
+        this.start = start;
+        this.end = end;
+        this.crunched = crunched;
+        this.audio = audio;
+      }
+      DataRequest.prototype = {
+        requests: {},
+        open: function(mode, name) {
+          this.name = name;
+          this.requests[name] = this;
+          Module['addRunDependency']('fp ' + this.name);
+        },
+        send: function() {},
+        onload: function() {
+          var byteArray = this.byteArray.subarray(this.start, this.end);
+
+          this.finish(byteArray);
+
+        },
+        finish: function(byteArray) {
+          var that = this;
+
+        Module['FS_createDataFile'](this.name, null, byteArray, true, true, true); // canOwn this data in the filesystem, it is a slide into the heap that will never change
+        Module['removeRunDependency']('fp ' + that.name);
+
+        this.requests[this.name] = null;
+      }
+    };
+
+    var files = metadata.files;
+    for (i = 0; i < files.length; ++i) {
+      new DataRequest(files[i].start, files[i].end, files[i].crunched, files[i].audio).open('GET', files[i].filename);
+    }
+
+
+    var indexedDB = window.indexedDB || window.mozIndexedDB || window.webkitIndexedDB || window.msIndexedDB;
+    var IDB_RO = "readonly";
+    var IDB_RW = "readwrite";
+    var DB_NAME = "EM_PRELOAD_CACHE";
+    var DB_VERSION = 1;
+    var METADATA_STORE_NAME = 'METADATA';
+    var PACKAGE_STORE_NAME = 'PACKAGES';
+    function openDatabase(callback, errback) {
+      try {
+        var openRequest = indexedDB.open(DB_NAME, DB_VERSION);
+      } catch (e) {
+        return errback(e);
+      }
+      openRequest.onupgradeneeded = function(event) {
+        var db = event.target.result;
+
+        if(db.objectStoreNames.contains(PACKAGE_STORE_NAME)) {
+          db.deleteObjectStore(PACKAGE_STORE_NAME);
+        }
+        var packages = db.createObjectStore(PACKAGE_STORE_NAME);
+
+        if(db.objectStoreNames.contains(METADATA_STORE_NAME)) {
+          db.deleteObjectStore(METADATA_STORE_NAME);
+        }
+        var metadata = db.createObjectStore(METADATA_STORE_NAME);
+      };
+      openRequest.onsuccess = function(event) {
+        var db = event.target.result;
+        callback(db);
+      };
+      openRequest.onerror = function(error) {
+        errback(error);
+      };
+    };
+
+    /* Check if there's a cached package, and if so whether it's the latest available */
+    function checkCachedPackage(db, packageName, callback, errback) {
+      var transaction = db.transaction([METADATA_STORE_NAME], IDB_RO);
+      var metadata = transaction.objectStore(METADATA_STORE_NAME);
+
+      var getRequest = metadata.get("metadata/" + packageName);
+      getRequest.onsuccess = function(event) {
+        var result = event.target.result;
+        if (!result) {
+          return callback(false);
+        } else {
+          return callback(PACKAGE_UUID === result.uuid);
+        }
+      };
+      getRequest.onerror = function(error) {
+        errback(error);
+      };
+    };
+
+    function fetchCachedPackage(db, packageName, callback, errback) {
+      var transaction = db.transaction([PACKAGE_STORE_NAME], IDB_RO);
+      var packages = transaction.objectStore(PACKAGE_STORE_NAME);
+
+      var getRequest = packages.get("package/" + packageName);
+      getRequest.onsuccess = function(event) {
+        var result = event.target.result;
+        callback(result);
+      };
+      getRequest.onerror = function(error) {
+        errback(error);
+      };
+    };
+
+    function cacheRemotePackage(db, packageName, packageData, packageMeta, callback, errback) {
+      var transaction_packages = db.transaction([PACKAGE_STORE_NAME], IDB_RW);
+      var packages = transaction_packages.objectStore(PACKAGE_STORE_NAME);
+
+      var putPackageRequest = packages.put(packageData, "package/" + packageName);
+      putPackageRequest.onsuccess = function(event) {
+        var transaction_metadata = db.transaction([METADATA_STORE_NAME], IDB_RW);
+        var metadata = transaction_metadata.objectStore(METADATA_STORE_NAME);
+        var putMetadataRequest = metadata.put(packageMeta, "metadata/" + packageName);
+        putMetadataRequest.onsuccess = function(event) {
+          callback(packageData);
+        };
+        putMetadataRequest.onerror = function(error) {
+          errback(error);
+        };
+      };
+      putPackageRequest.onerror = function(error) {
+        errback(error);
+      };
+    };
+
+    function processPackageData(arrayBuffer) {
+      Module.finishedDataFileDownloads++;
+      assert(arrayBuffer, 'Loading data file failed.');
+      assert(arrayBuffer instanceof ArrayBuffer, 'bad input to processPackageData');
+      var byteArray = new Uint8Array(arrayBuffer);
+      var curr;
+
+        // copy the entire loaded file into a spot in the heap. Files will refer to slices in that. They cannot be freed though
+        // (we may be allocating before malloc is ready, during startup).
+        if (Module['SPLIT_MEMORY']) Module.printErr('warning: you should run the file packager with --no-heap-copy when SPLIT_MEMORY is used, otherwise copying into the heap may fail due to the splitting');
+        var ptr = Module['getMemory'](byteArray.length);
+        Module['HEAPU8'].set(byteArray, ptr);
+        DataRequest.prototype.byteArray = Module['HEAPU8'].subarray(ptr, ptr+byteArray.length);
+
+        var files = metadata.files;
+        for (i = 0; i < files.length; ++i) {
+          DataRequest.prototype.requests[files[i].filename].onload();
+        }
+        Module['removeRunDependency']('datafile_game.data');
+
+      };
+      Module['addRunDependency']('datafile_game.data');
+
+      if (!Module.preloadResults) Module.preloadResults = {};
+
+      function preloadFallback(error) {
+        console.error(error);
+        console.error('falling back to default preload behavior');
+        fetchRemotePackage(REMOTE_PACKAGE_NAME, REMOTE_PACKAGE_SIZE, processPackageData, handleError);
+      };
+
+      openDatabase(
+        function(db) {
+          checkCachedPackage(db, PACKAGE_PATH + PACKAGE_NAME,
+             function(useCached) {
+              Module.preloadResults[PACKAGE_NAME] = {fromCache: useCached};
+                if (useCached && CACHEMODULE) {
+                console.info('loading ' + PACKAGE_NAME + ' from cache');
+                fetchCachedPackage(db, PACKAGE_PATH + PACKAGE_NAME, processPackageData, preloadFallback);
+              } else {
+                console.info('loading ' + PACKAGE_NAME + ' from remote');
+                fetchRemotePackage(REMOTE_PACKAGE_NAME, REMOTE_PACKAGE_SIZE,
+                  function(packageData) {
+                    if(CACHEMODULE){
+                    cacheRemotePackage(db, PACKAGE_PATH + PACKAGE_NAME, packageData, {uuid:PACKAGE_UUID}, processPackageData,
+                      function(error) {
+                        console.error(error);
+                        processPackageData(packageData);
+                      });}
+                      else {
+                          processPackageData(packageData);
+                      }
+                                       
+                  }
+                  , preloadFallback);
+              }
+            }
+            , preloadFallback);
+        }
+        , preloadFallback);
+
+      if (Module['setStatus']) Module['setStatus']('Downloading...');
+
+    }
+    if (Module['calledRun']) {
+      runWithFS();
+    } else {
+      if (!Module['preRun']) Module['preRun'] = [];
+      Module["preRun"].push(runWithFS); // FS is not initialized yet, wait for it
+    }
+
+  }
+  loadPackage({{{metadata}}});
+
+})();

buildtools/love-js/src/index.html

@@ -0,0 +1,162 @@
+<!doctype html>
+<html lang="en-us">
+  <head>
+    <meta charset="utf-8">
+    <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
+    <title>{{title}}</title>
+    <script src = "consolewrapper.js"></script>
+    <!-- Load custom style sheet -->
+    <link rel="stylesheet" type="text/css" href="theme/love.css">
+  </head>
+  <body>
+    <center>
+      <div>
+        <canvas id="canvas" oncontextmenu="event.preventDefault()"></canvas>
+        <canvas id="loadingCanvas" oncontextmenu="event.preventDefault()"
+                width="{{width}}" height="{{height}}"></canvas>
+      </div>
+    </center>
+
+    <script type='text/javascript'>
+      function goFullScreen(){
+          var canvas = document.getElementById("canvas");
+          if(canvas.requestFullScreen)
+              canvas.requestFullScreen();
+          else if(canvas.webkitRequestFullScreen)
+              canvas.webkitRequestFullScreen();
+          else if(canvas.mozRequestFullScreen)
+              canvas.mozRequestFullScreen();
+      }
+
+      function closeFullScreen() {
+          if (document.exitFullscreen) {
+              document.exitFullscreen();
+          } else if (document.webkitExitFullscreen) { /* Safari */
+              document.webkitExitFullscreen();
+          } else if (document.msExitFullscreen) { /* IE11 */
+              document.msExitFullscreen();
+          }
+      }
+
+      function toggleFullScreen(){
+          if((window.fullScreen) || /* firefox */
+             (window.innerWidth == screen.width &&  /* everything else */
+              window.innerHeight == screen.height)) {
+              closeFullScreen();
+          } else {
+              goFullScreen();
+          }
+      }
+     var loadingContext = document.getElementById('loadingCanvas').getContext('2d');
+     var complete = false;
+     function drawLoadingText(text, soFar, total) {
+          var canvas = loadingContext.canvas;
+          var ratio = complete ? 1 : 0;
+          if (soFar && total){
+              ratio = soFar / total
+          }
+         if (ratio == 1){
+             complete = true
+         }
+          //
+          loadingContext.fillStyle = "rgb({{canvas-colour}})";
+          loadingContext.fillRect(0, 0, canvas.scrollWidth, canvas.scrollHeight);
+
+          loadingContext.font = '2em arial';
+          loadingContext.textAlign = 'center'
+          //
+          loadingContext.fillStyle = "rgb({{text-colour}})";
+          loadingContext.fillText(text, canvas.scrollWidth / 2, (canvas.scrollHeight / 2) - 40);
+          //
+          loadingContext.beginPath();
+          loadingContext.strokeStyle = "rgb({{text-colour}})";
+          loadingContext.rect((canvas.scrollWidth / 2) - 200,
+                              ( canvas.scrollHeight / 2) - 20,
+                              400,
+                              40
+              
+              
+          );
+          loadingContext.stroke();
+          loadingContext.beginPath();
+          loadingContext.rect((canvas.scrollWidth / 2) - 200,
+                              ( canvas.scrollHeight / 2) - 20,
+                              400 * ratio,
+                              40
+              
+              
+          );
+          loadingContext.fill();
+          loadingContext.font = '4em arial';
+          loadingContext.fillText("{{title}}", canvas.scrollWidth / 2, canvas.scrollHeight / 4);
+          loadingContext.font = '2em arial';
+          loadingContext.fillText("{{version}}", canvas.scrollWidth / 2, (canvas.scrollHeight / 4 + 45));
+          loadingContext.font = '1em arial';
+          loadingContext.textAlign = 'left'
+          loadingContext.fillText("Powered By LÖVE", canvas.scrollWidth / 2 - 300, canvas.scrollHeight / 4 * 3);
+         loadingContext.textAlign = 'right'
+         loadingContext.fillText("Game By: {{author}}", canvas.scrollWidth / 2 + 300, canvas.scrollHeight / 4 * 3);
+     }
+
+     window.onload = function () { window.focus(); };
+      window.onclick = function () { window.focus(); };
+
+      window.addEventListener("keydown", function(e) {
+        // space and arrow keys
+        if([32, 37, 38, 39, 40].indexOf(e.keyCode) > -1) {
+          e.preventDefault();
+        }
+      }, false);
+
+      var Module = {
+          arguments: ["game.love","web"],
+        INITIAL_MEMORY: {{initial-memory}},
+        printErr: console.error.bind(console),
+        canvas: (function() {
+          var canvas = document.getElementById('canvas');
+
+          // As a default initial behavior, pop up an alert when webgl context is lost. To make your
+          // application robust, you may want to override this behavior before shipping!
+          // See http://www.khronos.org/registry/webgl/specs/latest/1.0/#5.15.2
+          canvas.addEventListener("webglcontextlost", function(e) { alert('WebGL context lost. You will need to reload the page.'); e.preventDefault(); }, false);
+
+          return canvas;
+        })(),
+        setStatus: function(text, soFar, total) {
+          if (text) {
+              drawLoadingText(text, soFar, total);
+          } else if (Module.remainingDependencies === 0) {
+            document.getElementById('loadingCanvas').style.display = 'none';
+            document.getElementById('canvas').style.display = 'block';
+          }
+        },
+        totalDependencies: 0,
+        remainingDependencies: 0,
+        monitorRunDependencies: function(left) {
+          this.remainingDependencies = left;
+          this.totalDependencies = Math.max(this.totalDependencies, left);
+          Module.setStatus(left ? 'Preparing... (' + (this.totalDependencies-left) + '/' + this.totalDependencies + ')' : 'All downloads complete.',
+                           this.totalDependencies-left,
+                           this.totalDependencies);
+        }
+      };
+      Module.setStatus('Downloading...');
+      window.onerror = function(event) {
+        // TODO: do not warn on ok events like simulating an infinite loop or exitStatus
+        Module.setStatus('Exception thrown, see JavaScript console');
+        Module.setStatus = function(text) {
+          if (text) Module.printErr('[post-exception status] ' + text);
+        };
+      };
+
+      var applicationLoad = function(e) {
+        Love(Module);
+      }
+    </script>
+    <script type="text/javascript" src="game.js"></script>
+    <script async type="text/javascript" src="love.js" onload="applicationLoad(this)"></script>
+    <!-- <footer> -->
+    <!--   <button onclick="goFullScreen();">Go Fullscreen</button> -->
+    <!-- </footer> -->
+  </body>
+</html>

buildtools/love-js/src/love-11.3/release/love.worker.js

@@ -0,0 +1 @@
+var threadInfoStruct=0;var selfThreadId=0;var parentThreadId=0;var Module={};function threadPrintErr(){var text=Array.prototype.slice.call(arguments).join(" ");console.error(text)}function threadAlert(){var text=Array.prototype.slice.call(arguments).join(" ");postMessage({cmd:"alert",text:text,threadId:selfThreadId})}var err=threadPrintErr;this.alert=threadAlert;Module["instantiateWasm"]=function(info,receiveInstance){var instance=new WebAssembly.Instance(Module["wasmModule"],info);Module["wasmModule"]=null;receiveInstance(instance);return instance.exports};this.onmessage=function(e){try{if(e.data.cmd==="load"){Module["DYNAMIC_BASE"]=e.data.DYNAMIC_BASE;Module["DYNAMICTOP_PTR"]=e.data.DYNAMICTOP_PTR;Module["wasmModule"]=e.data.wasmModule;Module["wasmMemory"]=e.data.wasmMemory;Module["buffer"]=Module["wasmMemory"].buffer;Module["ENVIRONMENT_IS_PTHREAD"]=true;if(typeof e.data.urlOrBlob==="string"){importScripts(e.data.urlOrBlob)}else{var objectUrl=URL.createObjectURL(e.data.urlOrBlob);importScripts(objectUrl);URL.revokeObjectURL(objectUrl)}Love(Module).then(function(instance){Module=instance;postMessage({"cmd":"loaded"})})}else if(e.data.cmd==="objectTransfer"){Module["PThread"].receiveObjectTransfer(e.data)}else if(e.data.cmd==="run"){Module["__performance_now_clock_drift"]=performance.now()-e.data.time;threadInfoStruct=e.data.threadInfoStruct;Module["registerPthreadPtr"](threadInfoStruct,0,0);selfThreadId=e.data.selfThreadId;parentThreadId=e.data.parentThreadId;var max=e.data.stackBase;var top=e.data.stackBase+e.data.stackSize;Module["establishStackSpace"](top,max);Module["_emscripten_tls_init"]();Module["PThread"].receiveObjectTransfer(e.data);Module["PThread"].setThreadStatus(Module["_pthread_self"](),1);try{var result=Module["dynCall"]("ii",e.data.start_routine,[e.data.arg]);if(!Module["getNoExitRuntime"]())Module["PThread"].threadExit(result)}catch(ex){if(ex==="Canceled!"){Module["PThread"].threadCancel()}else if(ex!="unwind"){Atomics.store(Module["HEAPU32"],threadInfoStruct+4>>2,ex instanceof Module["ExitStatus"]?ex.status:-2);Atomics.store(Module["HEAPU32"],threadInfoStruct+0>>2,1);Module["_emscripten_futex_wake"](threadInfoStruct+0,2147483647);if(!(ex instanceof Module["ExitStatus"]))throw ex}}}else if(e.data.cmd==="cancel"){if(threadInfoStruct){Module["PThread"].threadCancel()}}else if(e.data.target==="setimmediate"){}else if(e.data.cmd==="processThreadQueue"){if(threadInfoStruct){Module["_emscripten_current_thread_process_queued_calls"]()}}else{err("worker.js received unknown command "+e.data.cmd);err(e.data)}}catch(ex){err("worker.js onmessage() captured an uncaught exception: "+ex);if(ex.stack)err(ex.stack);throw ex}};if(typeof process==="object"&&typeof process.versions==="object"&&typeof process.versions.node==="string"){self={location:{href:__filename}};var onmessage=this.onmessage;var nodeWorkerThreads=require("worker_threads");global.Worker=nodeWorkerThreads.Worker;var parentPort=nodeWorkerThreads.parentPort;parentPort.on("message",function(data){onmessage({data:data})});var nodeFS=require("fs");var nodeRead=function(filename){return nodeFS.readFileSync(filename,"utf8")};function globalEval(x){global.require=require;global.Module=Module;eval.call(null,x)}importScripts=function(f){globalEval(nodeRead(f))};postMessage=function(msg){parentPort.postMessage(msg)};if(typeof performance==="undefined"){performance={now:function(){return Date.now()}}}}

buildtools/love-js/src/love-11.4/release/love.worker.js

@@ -0,0 +1 @@
+var threadInfoStruct=0;var selfThreadId=0;var parentThreadId=0;var Module={};function threadPrintErr(){var text=Array.prototype.slice.call(arguments).join(" ");console.error(text)}function threadAlert(){var text=Array.prototype.slice.call(arguments).join(" ");postMessage({cmd:"alert",text:text,threadId:selfThreadId})}var err=threadPrintErr;this.alert=threadAlert;Module["instantiateWasm"]=function(info,receiveInstance){var instance=new WebAssembly.Instance(Module["wasmModule"],info);Module["wasmModule"]=null;receiveInstance(instance);return instance.exports};this.onmessage=function(e){try{if(e.data.cmd==="load"){Module["DYNAMIC_BASE"]=e.data.DYNAMIC_BASE;Module["DYNAMICTOP_PTR"]=e.data.DYNAMICTOP_PTR;Module["wasmModule"]=e.data.wasmModule;Module["wasmMemory"]=e.data.wasmMemory;Module["buffer"]=Module["wasmMemory"].buffer;Module["ENVIRONMENT_IS_PTHREAD"]=true;if(typeof e.data.urlOrBlob==="string"){importScripts(e.data.urlOrBlob)}else{var objectUrl=URL.createObjectURL(e.data.urlOrBlob);importScripts(objectUrl);URL.revokeObjectURL(objectUrl)}Love(Module).then(function(instance){Module=instance;postMessage({"cmd":"loaded"})})}else if(e.data.cmd==="objectTransfer"){Module["PThread"].receiveObjectTransfer(e.data)}else if(e.data.cmd==="run"){Module["__performance_now_clock_drift"]=performance.now()-e.data.time;threadInfoStruct=e.data.threadInfoStruct;Module["registerPthreadPtr"](threadInfoStruct,0,0);selfThreadId=e.data.selfThreadId;parentThreadId=e.data.parentThreadId;var max=e.data.stackBase;var top=e.data.stackBase+e.data.stackSize;Module["establishStackSpace"](top,max);Module["_emscripten_tls_init"]();Module["PThread"].receiveObjectTransfer(e.data);Module["PThread"].setThreadStatus(Module["_pthread_self"](),1);try{var result=Module["dynCall_ii"](e.data.start_routine,e.data.arg);if(!Module["getNoExitRuntime"]())Module["PThread"].threadExit(result)}catch(ex){if(ex==="Canceled!"){Module["PThread"].threadCancel()}else if(ex!="unwind"){Atomics.store(Module["HEAPU32"],threadInfoStruct+4>>2,ex instanceof Module["ExitStatus"]?ex.status:-2);Atomics.store(Module["HEAPU32"],threadInfoStruct+0>>2,1);Module["_emscripten_futex_wake"](threadInfoStruct+0,2147483647);if(!(ex instanceof Module["ExitStatus"]))throw ex}}}else if(e.data.cmd==="cancel"){if(threadInfoStruct){Module["PThread"].threadCancel()}}else if(e.data.target==="setimmediate"){}else if(e.data.cmd==="processThreadQueue"){if(threadInfoStruct){Module["_emscripten_current_thread_process_queued_calls"]()}}else{err("worker.js received unknown command "+e.data.cmd);err(e.data)}}catch(ex){err("worker.js onmessage() captured an uncaught exception: "+ex);if(ex.stack)err(ex.stack);throw ex}};if(typeof process==="object"&&typeof process.versions==="object"&&typeof process.versions.node==="string"){self={location:{href:__filename}};var onmessage=this.onmessage;var nodeWorkerThreads=require("worker_threads");global.Worker=nodeWorkerThreads.Worker;var parentPort=nodeWorkerThreads.parentPort;parentPort.on("message",function(data){onmessage({data:data})});var nodeFS=require("fs");var nodeRead=function(filename){return nodeFS.readFileSync(filename,"utf8")};function globalEval(x){global.require=require;global.Module=Module;eval.call(null,x)}importScripts=function(f){globalEval(nodeRead(f))};postMessage=function(msg){parentPort.postMessage(msg)};if(typeof performance==="undefined"){performance={now:function(){return Date.now()}}}}

buildtools/love-js/src/love-11.5/release/love.worker.js

@@ -0,0 +1 @@
+"use strict";var Module={};var ENVIRONMENT_IS_NODE=typeof process=="object"&&typeof process.versions=="object"&&typeof process.versions.node=="string";if(ENVIRONMENT_IS_NODE){var nodeWorkerThreads=require("worker_threads");var parentPort=nodeWorkerThreads.parentPort;parentPort.on("message",data=>onmessage({data:data}));var fs=require("fs");var vm=require("vm");Object.assign(global,{self:global,require:require,Module:Module,location:{href:__filename},Worker:nodeWorkerThreads.Worker,importScripts:f=>vm.runInThisContext(fs.readFileSync(f,"utf8"),{filename:f}),postMessage:msg=>parentPort.postMessage(msg),performance:global.performance||{now:Date.now}})}var initializedJS=false;function threadPrintErr(...args){var text=args.join(" ");if(ENVIRONMENT_IS_NODE){fs.writeSync(2,text+"\n");return}console.error(text)}function threadAlert(...args){var text=args.join(" ");postMessage({cmd:"alert",text:text,threadId:Module["_pthread_self"]()})}var err=threadPrintErr;self.alert=threadAlert;Module["instantiateWasm"]=(info,receiveInstance)=>{var module=Module["wasmModule"];Module["wasmModule"]=null;var instance=new WebAssembly.Instance(module,info);return receiveInstance(instance,module)};self.onunhandledrejection=e=>{throw e.reason||e};function handleMessage(e){try{if(e.data.cmd==="load"){let messageQueue=[];self.onmessage=e=>messageQueue.push(e);self.startWorker=instance=>{Module=instance;postMessage({"cmd":"loaded"});for(let msg of messageQueue){handleMessage(msg)}self.onmessage=handleMessage};Module["wasmModule"]=e.data.wasmModule;for(const handler of e.data.handlers){Module[handler]=(...args)=>{postMessage({cmd:"callHandler",handler:handler,args:args})}}Module["wasmMemory"]=e.data.wasmMemory;Module["buffer"]=Module["wasmMemory"].buffer;Module["ENVIRONMENT_IS_PTHREAD"]=true;if(typeof e.data.urlOrBlob=="string"){importScripts(e.data.urlOrBlob)}else{var objectUrl=URL.createObjectURL(e.data.urlOrBlob);importScripts(objectUrl);URL.revokeObjectURL(objectUrl)}Love(Module)}else if(e.data.cmd==="run"){Module["__emscripten_thread_init"](e.data.pthread_ptr,0,0,1);Module["__emscripten_thread_mailbox_await"](e.data.pthread_ptr);Module["establishStackSpace"]();Module["PThread"].receiveObjectTransfer(e.data);Module["PThread"].threadInitTLS();if(!initializedJS){initializedJS=true}try{Module["invokeEntryPoint"](e.data.start_routine,e.data.arg)}catch(ex){if(ex!="unwind"){throw ex}}}else if(e.data.cmd==="cancel"){if(Module["_pthread_self"]()){Module["__emscripten_thread_exit"](-1)}}else if(e.data.target==="setimmediate"){}else if(e.data.cmd==="checkMailbox"){if(initializedJS){Module["checkMailbox"]()}}else if(e.data.cmd){err(`worker.js received unknown command ${e.data.cmd}`);err(e.data)}}catch(ex){Module["__emscripten_thread_crashed"]?.();throw ex}}self.onmessage=handleMessage;

buildtools/love-js/src/love.css

@@ -0,0 +1,48 @@
+* {
+    box-sizing: border-box;
+}
+
+h1 {
+    font-family: arial;
+    color: rgb( 11, 86, 117 );
+}
+
+body {
+    background-repeat: no-repeat;
+    font-family: arial;
+    margin: 0;
+    padding: none;
+    background-color: rgb({{page-colour}});
+    color: rgb( 28, 78, 104 );
+}
+
+footer {
+    font-family: arial;
+    font-size: 12px;
+    padding-left: 10px;
+    padding-bottom: 10px;
+    position:absolute;
+    bottom: 0;
+    width: 100%;
+}
+
+/* Links */
+a {
+    text-decoration: none;
+}
+a:link {
+    color: rgb( 233, 73, 154 );
+}
+a:visited {
+    color: rgb( 110, 30, 71 );
+}
+a:hover {
+    color: rgb( 252, 207, 230 );
+}
+
+/* the canvas *must not* have any border or padding, or mouse coords will be wrong */
+#canvas {
+    padding-right: 0;
+    display: none;
+    border: 0px none;
+}

buildtools/love-js/src/serve.py

@@ -0,0 +1,22 @@
+#!/usr/bin/env python
+
+# Attribution: https://stackoverflow.com/questions/21956683/enable-access-control-on-simple-http-server
+
+try:
+    # Python 3
+    from http.server import HTTPServer, SimpleHTTPRequestHandler, test as test_orig
+    import sys
+    def test (*args):
+        test_orig(*args, port=int(sys.argv[1]) if len(sys.argv) > 1 else 8000)
+except ImportError: # Python 2
+    from BaseHTTPServer import HTTPServer, test
+    from SimpleHTTPServer import SimpleHTTPRequestHandler
+
+class CORSRequestHandler (SimpleHTTPRequestHandler):
+    def end_headers (self):
+        self.send_header('Cross-Origin-Opener-Policy', 'same-origin')
+        self.send_header('Cross-Origin-Embedder-Policy', 'require-corp')
+        SimpleHTTPRequestHandler.end_headers(self)
+
+if __name__ == '__main__':
+    test(CORSRequestHandler, HTTPServer)

conf.lua

@@ -0,0 +1,10 @@
+love.conf = function(t)
+   t.gammacorrect = true
+   t.title, t.identity = "Space Crawler", "Bill Niblock"
+   t.modules.joystick = false
+   t.modules.physics = false
+   t.window.width = 1280
+   t.window.height = 720
+   t.window.vsync = false
+   t.version = "11.5"
+end

error-mode.fnl

@@ -0,0 +1,41 @@
+;; This mode has two purposes:
+;; * display the stack trace that caused the error
+;; * allow the user to decide whether to retry after reloading or quit
+
+;; Since we can't know which module needs to be reloaded, we rely on the user
+;; doing a ,reload foo in the repl.
+
+(local state {:msg "" :traceback "" :old-mode :intro})
+
+(local explanation "Press escape to quit.
+Press space to return to the previous mode after reloading in the repl.")
+
+(fn draw []
+  (love.graphics.clear 0.34 0.61 0.86)
+  (love.graphics.setColor 0.9 0.9 0.9)
+  (love.graphics.print explanation 15 10)
+  (love.graphics.print state.msg 10 60)
+  (love.graphics.print state.traceback 15 125))
+
+(fn keypressed [key set-mode]
+  (match key
+    :escape (love.event.quit)
+    :space (set-mode state.old-mode)))
+
+(fn color-msg [msg]
+  ;; convert compiler's ansi escape codes to love2d-friendly codes
+  (case (msg:match "(.*)\027%[7m(.*)\027%[0m(.*)")
+    (pre selected post) [[1 1 1] pre
+                         [1 0.2 0.2] selected
+                         [1 1 1] post]
+    _ msg))
+
+(fn activate [old-mode msg traceback]
+  (love.graphics.setNewFont 16) ; use a monospace font here if you have one
+  (print msg)
+  (print traceback)
+  (set state.old-mode old-mode)
+  (set state.msg (color-msg msg))
+  (set state.traceback traceback))
+
+{: draw : keypressed : activate}

lib/lume.lua

@@ -0,0 +1,780 @@
+--
+-- lume
+--
+-- Copyright (c) 2018 rxi
+--
+-- Permission is hereby granted, free of charge, to any person obtaining a copy of
+-- this software and associated documentation files (the "Software"), to deal in
+-- the Software without restriction, including without limitation the rights to
+-- use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+-- of the Software, and to permit persons to whom the Software is furnished to do
+-- so, subject to the following conditions:
+--
+-- The above copyright notice and this permission notice shall be included in all
+-- copies or substantial portions of the Software.
+--
+-- THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+-- IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+-- FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+-- AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+-- LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+-- OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+-- SOFTWARE.
+--
+
+local lume = { _version = "2.3.0" }
+
+local pairs, ipairs = pairs, ipairs
+local type, assert, unpack = type, assert, unpack or table.unpack
+local tostring, tonumber = tostring, tonumber
+local math_floor = math.floor
+local math_ceil = math.ceil
+local math_atan2 = math.atan2 or math.atan
+local math_sqrt = math.sqrt
+local math_abs = math.abs
+
+local noop = function()
+end
+
+local identity = function(x)
+  return x
+end
+
+local patternescape = function(str)
+  return str:gsub("[%(%)%.%%%+%-%*%?%[%]%^%$]", "%%%1")
+end
+
+local absindex = function(len, i)
+  return i < 0 and (len + i + 1) or i
+end
+
+local iscallable = function(x)
+  if type(x) == "function" then return true end
+  local mt = getmetatable(x)
+  return mt and mt.__call ~= nil
+end
+
+local getiter = function(x)
+  if lume.isarray(x) then
+    return ipairs
+  elseif type(x) == "table" then
+    return pairs
+  end
+  error("expected table", 3)
+end
+
+local iteratee = function(x)
+  if x == nil then return identity end
+  if iscallable(x) then return x end
+  if type(x) == "table" then
+    return function(z)
+      for k, v in pairs(x) do
+        if z[k] ~= v then return false end
+      end
+      return true
+    end
+  end
+  return function(z) return z[x] end
+end
+
+
+
+function lume.clamp(x, min, max)
+  return x < min and min or (x > max and max or x)
+end
+
+
+function lume.round(x, increment)
+  if increment then return lume.round(x / increment) * increment end
+  return x >= 0 and math_floor(x + .5) or math_ceil(x - .5)
+end
+
+
+function lume.sign(x)
+  return x < 0 and -1 or 1
+end
+
+
+function lume.lerp(a, b, amount)
+  return a + (b - a) * lume.clamp(amount, 0, 1)
+end
+
+
+function lume.smooth(a, b, amount)
+  local t = lume.clamp(amount, 0, 1)
+  local m = t * t * (3 - 2 * t)
+  return a + (b - a) * m
+end
+
+
+function lume.pingpong(x)
+  return 1 - math_abs(1 - x % 2)
+end
+
+
+function lume.distance(x1, y1, x2, y2, squared)
+  local dx = x1 - x2
+  local dy = y1 - y2
+  local s = dx * dx + dy * dy
+  return squared and s or math_sqrt(s)
+end
+
+
+function lume.angle(x1, y1, x2, y2)
+  return math_atan2(y2 - y1, x2 - x1)
+end
+
+
+function lume.vector(angle, magnitude)
+  return math.cos(angle) * magnitude, math.sin(angle) * magnitude
+end
+
+
+function lume.random(a, b)
+  if not a then a, b = 0, 1 end
+  if not b then b = 0 end
+  return a + math.random() * (b - a)
+end
+
+
+function lume.randomchoice(t)
+  return t[math.random(#t)]
+end
+
+
+function lume.weightedchoice(t)
+  local sum = 0
+  for _, v in pairs(t) do
+    assert(v >= 0, "weight value less than zero")
+    sum = sum + v
+  end
+  assert(sum ~= 0, "all weights are zero")
+  local rnd = lume.random(sum)
+  for k, v in pairs(t) do
+    if rnd < v then return k end
+    rnd = rnd - v
+  end
+end
+
+
+function lume.isarray(x)
+  return type(x) == "table" and x[1] ~= nil
+end
+
+
+function lume.push(t, ...)
+  local n = select("#", ...)
+  for i = 1, n do
+    t[#t + 1] = select(i, ...)
+  end
+  return ...
+end
+
+
+function lume.remove(t, x)
+  local iter = getiter(t)
+  for i, v in iter(t) do
+    if v == x then
+      if lume.isarray(t) then
+        table.remove(t, i)
+        break
+      else
+        t[i] = nil
+        break
+      end
+    end
+  end
+  return x
+end
+
+
+function lume.clear(t)
+  local iter = getiter(t)
+  for k in iter(t) do
+    t[k] = nil
+  end
+  return t
+end
+
+
+function lume.extend(t, ...)
+  for i = 1, select("#", ...) do
+    local x = select(i, ...)
+    if x then
+      for k, v in pairs(x) do
+        t[k] = v
+      end
+    end
+  end
+  return t
+end
+
+
+function lume.shuffle(t)
+  local rtn = {}
+  for i = 1, #t do
+    local r = math.random(i)
+    if r ~= i then
+      rtn[i] = rtn[r]
+    end
+    rtn[r] = t[i]
+  end
+  return rtn
+end
+
+
+function lume.sort(t, comp)
+  local rtn = lume.clone(t)
+  if comp then
+    if type(comp) == "string" then
+      table.sort(rtn, function(a, b) return a[comp] < b[comp] end)
+    else
+      table.sort(rtn, comp)
+    end
+  else
+    table.sort(rtn)
+  end
+  return rtn
+end
+
+
+function lume.array(...)
+  local t = {}
+  for x in ... do t[#t + 1] = x end
+  return t
+end
+
+
+function lume.each(t, fn, ...)
+  local iter = getiter(t)
+  if type(fn) == "string" then
+    for _, v in iter(t) do v[fn](v, ...) end
+  else
+    for _, v in iter(t) do fn(v, ...) end
+  end
+  return t
+end
+
+
+function lume.map(t, fn)
+  fn = iteratee(fn)
+  local iter = getiter(t)
+  local rtn = {}
+  for k, v in iter(t) do rtn[k] = fn(v) end
+  return rtn
+end
+
+
+function lume.all(t, fn)
+  fn = iteratee(fn)
+  local iter = getiter(t)
+  for _, v in iter(t) do
+    if not fn(v) then return false end
+  end
+  return true
+end
+
+
+function lume.any(t, fn)
+  fn = iteratee(fn)
+  local iter = getiter(t)
+  for _, v in iter(t) do
+    if fn(v) then return true end
+  end
+  return false
+end
+
+
+function lume.reduce(t, fn, first)
+  local acc = first
+  local started = first and true or false
+  local iter = getiter(t)
+  for _, v in iter(t) do
+    if started then
+      acc = fn(acc, v)
+    else
+      acc = v
+      started = true
+    end
+  end
+  assert(started, "reduce of an empty table with no first value")
+  return acc
+end
+
+
+function lume.unique(t)
+  local rtn = {}
+  for k in pairs(lume.invert(t)) do
+    rtn[#rtn + 1] = k
+  end
+  return rtn
+end
+
+
+function lume.filter(t, fn, retainkeys)
+  fn = iteratee(fn)
+  local iter = getiter(t)
+  local rtn = {}
+  if retainkeys then
+    for k, v in iter(t) do
+      if fn(v) then rtn[k] = v end
+    end
+  else
+    for _, v in iter(t) do
+      if fn(v) then rtn[#rtn + 1] = v end
+    end
+  end
+  return rtn
+end
+
+
+function lume.reject(t, fn, retainkeys)
+  fn = iteratee(fn)
+  local iter = getiter(t)
+  local rtn = {}
+  if retainkeys then
+    for k, v in iter(t) do
+      if not fn(v) then rtn[k] = v end
+    end
+  else
+    for _, v in iter(t) do
+      if not fn(v) then rtn[#rtn + 1] = v end
+    end
+  end
+  return rtn
+end
+
+
+function lume.merge(...)
+  local rtn = {}
+  for i = 1, select("#", ...) do
+    local t = select(i, ...)
+    local iter = getiter(t)
+    for k, v in iter(t) do
+      rtn[k] = v
+    end
+  end
+  return rtn
+end
+
+
+function lume.concat(...)
+  local rtn = {}
+  for i = 1, select("#", ...) do
+    local t = select(i, ...)
+    if t ~= nil then
+      local iter = getiter(t)
+      for _, v in iter(t) do
+        rtn[#rtn + 1] = v
+      end
+    end
+  end
+  return rtn
+end
+
+
+function lume.find(t, value)
+  local iter = getiter(t)
+  for k, v in iter(t) do
+    if v == value then return k end
+  end
+  return nil
+end
+
+
+function lume.match(t, fn)
+  fn = iteratee(fn)
+  local iter = getiter(t)
+  for k, v in iter(t) do
+    if fn(v) then return v, k end
+  end
+  return nil
+end
+
+
+function lume.count(t, fn)
+  local count = 0
+  local iter = getiter(t)
+  if fn then
+    fn = iteratee(fn)
+    for _, v in iter(t) do
+      if fn(v) then count = count + 1 end
+    end
+  else
+    if lume.isarray(t) then
+      return #t
+    end
+    for _ in iter(t) do count = count + 1 end
+  end
+  return count
+end
+
+
+function lume.slice(t, i, j)
+  i = i and absindex(#t, i) or 1
+  j = j and absindex(#t, j) or #t
+  local rtn = {}
+  for x = i < 1 and 1 or i, j > #t and #t or j do
+    rtn[#rtn + 1] = t[x]
+  end
+  return rtn
+end
+
+
+function lume.first(t, n)
+  if not n then return t[1] end
+  return lume.slice(t, 1, n)
+end
+
+
+function lume.last(t, n)
+  if not n then return t[#t] end
+  return lume.slice(t, -n, -1)
+end
+
+
+function lume.invert(t)
+  local rtn = {}
+  for k, v in pairs(t) do rtn[v] = k end
+  return rtn
+end
+
+
+function lume.pick(t, ...)
+  local rtn = {}
+  for i = 1, select("#", ...) do
+    local k = select(i, ...)
+    rtn[k] = t[k]
+  end
+  return rtn
+end
+
+
+function lume.keys(t)
+  local rtn = {}
+  local iter = getiter(t)
+  for k in iter(t) do rtn[#rtn + 1] = k end
+  return rtn
+end
+
+
+function lume.clone(t)
+  local rtn = {}
+  for k, v in pairs(t) do rtn[k] = v end
+  return rtn
+end
+
+
+function lume.fn(fn, ...)
+  assert(iscallable(fn), "expected a function as the first argument")
+  local args = { ... }
+  return function(...)
+    local a = lume.concat(args, { ... })
+    return fn(unpack(a))
+  end
+end
+
+
+function lume.once(fn, ...)
+  local f = lume.fn(fn, ...)
+  local done = false
+  return function(...)
+    if done then return end
+    done = true
+    return f(...)
+  end
+end
+
+
+local memoize_fnkey = {}
+local memoize_nil = {}
+
+function lume.memoize(fn)
+  local cache = {}
+  return function(...)
+    local c = cache
+    for i = 1, select("#", ...) do
+      local a = select(i, ...) or memoize_nil
+      c[a] = c[a] or {}
+      c = c[a]
+    end
+    c[memoize_fnkey] = c[memoize_fnkey] or {fn(...)}
+    return unpack(c[memoize_fnkey])
+  end
+end
+
+
+function lume.combine(...)
+  local n = select('#', ...)
+  if n == 0 then return noop end
+  if n == 1 then
+    local fn = select(1, ...)
+    if not fn then return noop end
+    assert(iscallable(fn), "expected a function or nil")
+    return fn
+  end
+  local funcs = {}
+  for i = 1, n do
+    local fn = select(i, ...)
+    if fn ~= nil then
+      assert(iscallable(fn), "expected a function or nil")
+      funcs[#funcs + 1] = fn
+    end
+  end
+  return function(...)
+    for _, f in ipairs(funcs) do f(...) end
+  end
+end
+
+
+function lume.call(fn, ...)
+  if fn then
+    return fn(...)
+  end
+end
+
+
+function lume.time(fn, ...)
+  local start = os.clock()
+  local rtn = {fn(...)}
+  return (os.clock() - start), unpack(rtn)
+end
+
+
+local lambda_cache = {}
+
+function lume.lambda(str)
+  if not lambda_cache[str] then
+    local args, body = str:match([[^([%w,_ ]-)%->(.-)$]])
+    assert(args and body, "bad string lambda")
+    local s = "return function(" .. args .. ")\nreturn " .. body .. "\nend"
+    lambda_cache[str] = lume.dostring(s)
+  end
+  return lambda_cache[str]
+end
+
+
+local serialize
+
+local serialize_map = {
+  [ "boolean" ] = tostring,
+  [ "nil"     ] = tostring,
+  [ "string"  ] = function(v) return string.format("%q", v) end,
+  [ "number"  ] = function(v)
+    if      v ~=  v     then return  "0/0"      --  nan
+    elseif  v ==  1 / 0 then return  "1/0"      --  inf
+    elseif  v == -1 / 0 then return "-1/0" end  -- -inf
+    return tostring(v)
+  end,
+  [ "table"   ] = function(t, stk)
+    stk = stk or {}
+    if stk[t] then error("circular reference") end
+    local rtn = {}
+    stk[t] = true
+    for k, v in pairs(t) do
+      rtn[#rtn + 1] = "[" .. serialize(k, stk) .. "]=" .. serialize(v, stk)
+    end
+    stk[t] = nil
+    return "{" .. table.concat(rtn, ",") .. "}"
+  end
+}
+
+setmetatable(serialize_map, {
+  __index = function(_, k) error("unsupported serialize type: " .. k) end
+})
+
+serialize = function(x, stk)
+  return serialize_map[type(x)](x, stk)
+end
+
+function lume.serialize(x)
+  return serialize(x)
+end
+
+
+function lume.deserialize(str)
+  return lume.dostring("return " .. str)
+end
+
+
+function lume.split(str, sep)
+  if not sep then
+    return lume.array(str:gmatch("([%S]+)"))
+  else
+    assert(sep ~= "", "empty separator")
+    local psep = patternescape(sep)
+    return lume.array((str..sep):gmatch("(.-)("..psep..")"))
+  end
+end
+
+
+function lume.trim(str, chars)
+  if not chars then return str:match("^[%s]*(.-)[%s]*$") end
+  chars = patternescape(chars)
+  return str:match("^[" .. chars .. "]*(.-)[" .. chars .. "]*$")
+end
+
+
+function lume.wordwrap(str, limit)
+  limit = limit or 72
+  local check
+  if type(limit) == "number" then
+    check = function(s) return #s >= limit end
+  else
+    check = limit
+  end
+  local rtn = {}
+  local line = ""
+  for word, spaces in str:gmatch("(%S+)(%s*)") do
+    local s = line .. word
+    if check(s) then
+      table.insert(rtn, line .. "\n")
+      line = word
+    else
+      line = s
+    end
+    for c in spaces:gmatch(".") do
+      if c == "\n" then
+        table.insert(rtn, line .. "\n")
+        line = ""
+      else
+        line = line .. c
+      end
+    end
+  end
+  table.insert(rtn, line)
+  return table.concat(rtn)
+end
+
+
+function lume.format(str, vars)
+  if not vars then return str end
+  local f = function(x)
+    return tostring(vars[x] or vars[tonumber(x)] or "{" .. x .. "}")
+  end
+  return (str:gsub("{(.-)}", f))
+end
+
+
+function lume.trace(...)
+  local info = debug.getinfo(2, "Sl")
+  local t = { info.short_src .. ":" .. info.currentline .. ":" }
+  for i = 1, select("#", ...) do
+    local x = select(i, ...)
+    if type(x) == "number" then
+      x = string.format("%g", lume.round(x, .01))
+    end
+    t[#t + 1] = tostring(x)
+  end
+  print(table.concat(t, " "))
+end
+
+
+function lume.dostring(str)
+  return assert((loadstring or load)(str))()
+end
+
+
+function lume.uuid()
+  local fn = function(x)
+    local r = math.random(16) - 1
+    r = (x == "x") and (r + 1) or (r % 4) + 9
+    return ("0123456789abcdef"):sub(r, r)
+  end
+  return (("xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx"):gsub("[xy]", fn))
+end
+
+
+function lume.hotswap(modname)
+  local oldglobal = lume.clone(_G)
+  local updated = {}
+  local function update(old, new)
+    if updated[old] then return end
+    updated[old] = true
+    local oldmt, newmt = getmetatable(old), getmetatable(new)
+    if oldmt and newmt then update(oldmt, newmt) end
+    for k, v in pairs(new) do
+      if type(v) == "table" then update(old[k], v) else old[k] = v end
+    end
+  end
+  local err = nil
+  local function onerror(e)
+    for k in pairs(_G) do _G[k] = oldglobal[k] end
+    err = lume.trim(e)
+  end
+  local ok, oldmod = pcall(require, modname)
+  oldmod = ok and oldmod or nil
+  xpcall(function()
+    package.loaded[modname] = nil
+    local newmod = require(modname)
+    if type(oldmod) == "table" then update(oldmod, newmod) end
+    for k, v in pairs(oldglobal) do
+      if v ~= _G[k] and type(v) == "table" then
+        update(v, _G[k])
+        _G[k] = v
+      end
+    end
+  end, onerror)
+  package.loaded[modname] = oldmod
+  if err then return nil, err end
+  return oldmod
+end
+
+
+local ripairs_iter = function(t, i)
+  i = i - 1
+  local v = t[i]
+  if v ~= nil then 
+    return i, v
+  end
+end
+
+function lume.ripairs(t)
+  return ripairs_iter, t, (#t + 1)
+end
+
+
+function lume.color(str, mul)
+  mul = mul or 1
+  local r, g, b, a
+  r, g, b = str:match("#(%x%x)(%x%x)(%x%x)")
+  if r then
+    r = tonumber(r, 16) / 0xff
+    g = tonumber(g, 16) / 0xff
+    b = tonumber(b, 16) / 0xff
+    a = 1
+  elseif str:match("rgba?%s*%([%d%s%.,]+%)") then
+    local f = str:gmatch("[%d.]+")
+    r = (f() or 0) / 0xff
+    g = (f() or 0) / 0xff
+    b = (f() or 0) / 0xff
+    a = f() or 1
+  else
+    error(("bad color string '%s'"):format(str))
+  end
+  return r * mul, g * mul, b * mul, a * mul
+end
+
+
+local chain_mt = {}
+chain_mt.__index = lume.map(lume.filter(lume, iscallable, true),
+  function(fn)
+    return function(self, ...)
+      self._value = fn(self._value, ...)
+      return self
+    end
+  end)
+chain_mt.__index.result = function(x) return x._value end
+
+function lume.chain(value)
+  return setmetatable({ _value = value }, chain_mt)
+end
+
+setmetatable(lume,  {
+  __call = function(_, ...)
+    return lume.chain(...)
+  end
+})
+
+
+return lume

lib/stdio.fnl

@@ -0,0 +1,51 @@
+(local fennel (require :lib.fennel))
+(require :love.event)
+
+;; This module exists in order to expose stdio over a channel so that it
+;; can be used in a non-blocking way from another thread.
+
+(fn prompt [cont?]
+  (io.write (if cont? ".." ">> ")) (io.flush) (.. (tostring (io.read)) "\n"))
+
+;; This module is loaded twice: initially in the main thread where ... is nil,
+;; and then again in a separate thread where ... contains the channel used to
+;; communicate with the main thread.
+
+(fn looper [event channel]
+  (match (channel:demand)
+    [:write vals] (do (io.write (table.concat vals "\t"))
+                      (io.write "\n"))
+    [:read cont?] (love.event.push event (prompt cont?)))
+  (looper event channel))
+
+(match ...
+  (event channel) (looper event channel))
+
+{:start (fn start-repl []
+          (let [code (love.filesystem.read "lib/stdio.fnl")
+                luac (if code
+                         (love.filesystem.newFileData
+                          (fennel.compileString code) "io")
+                         (love.filesystem.read "lib/stdio.lua"))
+                thread (love.thread.newThread luac)
+                io-channel (love.thread.newChannel)
+                ;; fennel 1.5 has updated repl to be a table
+                ;; with a metatable __call value. coroutine.create
+                ;; does not reference the metatable __call value
+                ;; by applying partial we fix this issue in a
+                ;; backwards compatible way.
+                coro (coroutine.create (partial fennel.repl))
+                options {:readChunk (fn [{: stack-size}]
+                                      (io-channel:push [:read (< 0 stack-size)])
+                                      (coroutine.yield))
+                         :onValues (fn [vals]
+                                     (io-channel:push [:write vals]))
+                         :onError (fn [errtype err]
+                                    (io-channel:push [:write [err]]))
+                         :moduleName "lib.fennel"}]
+            ;; this thread will send "eval" events for us to consume:
+            (coroutine.resume coro options)
+            (thread:start "eval" io-channel)
+            (set love.handlers.eval
+                 (fn [input]
+                   (coroutine.resume coro input)))))}

lib/stdio.lua

@@ -0,0 +1,76 @@
+local fennel = require("lib.fennel")
+require("love.event")
+local function prompt(cont_3f)
+  local function _1_()
+    if cont_3f then
+      return ".."
+    else
+      return ">> "
+    end
+  end
+  io.write(_1_())
+  io.flush()
+  return (tostring(io.read()) .. "\n")
+end
+local function looper(event, channel)
+  do
+    local _2_ = channel:demand()
+    if ((_G.type(_2_) == "table") and (_2_[1] == "write") and (nil ~= _2_[2])) then
+      local vals = _2_[2]
+      io.write(table.concat(vals, "\9"))
+      io.write("\n")
+    elseif ((_G.type(_2_) == "table") and (_2_[1] == "read") and (nil ~= _2_[2])) then
+      local cont_3f = _2_[2]
+      love.event.push(event, prompt(cont_3f))
+    else
+    end
+  end
+  return looper(event, channel)
+end
+do
+  local _4_, _5_ = ...
+  if ((nil ~= _4_) and (nil ~= _5_)) then
+    local event = _4_
+    local channel = _5_
+    looper(event, channel)
+  else
+  end
+end
+local function start_repl()
+  local code = love.filesystem.read("lib/stdio.fnl")
+  local luac
+  if code then
+    luac = love.filesystem.newFileData(fennel.compileString(code), "io")
+  else
+    luac = love.filesystem.read("lib/stdio.lua")
+  end
+  local thread = love.thread.newThread(luac)
+  local io_channel = love.thread.newChannel()
+  local coro
+  local function _8_(...)
+    return fennel.repl(...)
+  end
+  coro = coroutine.create(_8_)
+  local options
+  local function _11_(_9_)
+    local _arg_10_ = _9_
+    local stack_size = _arg_10_["stack-size"]
+    io_channel:push({"read", (0 < stack_size)})
+    return coroutine.yield()
+  end
+  local function _12_(vals)
+    return io_channel:push({"write", vals})
+  end
+  local function _13_(errtype, err)
+    return io_channel:push({"write", {err}})
+  end
+  options = {readChunk = _11_, onValues = _12_, onError = _13_, moduleName = "lib.fennel"}
+  coroutine.resume(coro, options)
+  thread:start("eval", io_channel)
+  local function _14_(input)
+    return coroutine.resume(coro, input)
+  end
+  love.handlers.eval = _14_
+  return nil
+end
+return {start = start_repl}

license.txt

@@ -0,0 +1,674 @@
+                    GNU GENERAL PUBLIC LICENSE
+                       Version 3, 29 June 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc. <https://fsf.org/>
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+                            Preamble
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+  A patent license is "discriminatory" if it does not include within
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+contain the covered work, unless you entered into that arrangement,
+or that patent license was granted, prior to 28 March 2007.
+
+  Nothing in this License shall be construed as excluding or limiting
+any implied license or other defenses to infringement that may
+otherwise be available to you under applicable patent law.
+
+  12. No Surrender of Others' Freedom.
+
+  If conditions are imposed on you (whether by court order, agreement or
+otherwise) that contradict the conditions of this License, they do not
+excuse you from the conditions of this License.  If you cannot convey a
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+not convey it at all.  For example, if you agree to terms that obligate you
+to collect a royalty for further conveying from those to whom you convey
+the Program, the only way you could satisfy both those terms and this
+License would be to refrain entirely from conveying the Program.
+
+  13. Use with the GNU Affero General Public License.
+
+  Notwithstanding any other provision of this License, you have
+permission to link or combine any covered work with a work licensed
+under version 3 of the GNU Affero General Public License into a single
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+License will continue to apply to the part which is the covered work,
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+combination as such.
+
+  14. Revised Versions of this License.
+
+  The Free Software Foundation may publish revised and/or new versions of
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+be similar in spirit to the present version, but may differ in detail to
+address new problems or concerns.
+
+  Each version is given a distinguishing version number.  If the
+Program specifies that a certain numbered version of the GNU General
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+option of following the terms and conditions either of that numbered
+version or of any later version published by the Free Software
+Foundation.  If the Program does not specify a version number of the
+GNU General Public License, you may choose any version ever published
+by the Free Software Foundation.
+
+  If the Program specifies that a proxy can decide which future
+versions of the GNU General Public License can be used, that proxy's
+public statement of acceptance of a version permanently authorizes you
+to choose that version for the Program.
+
+  Later license versions may give you additional or different
+permissions.  However, no additional obligations are imposed on any
+author or copyright holder as a result of your choosing to follow a
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+  15. Disclaimer of Warranty.
+
+  THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
+APPLICABLE LAW.  EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
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+PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
+EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGES.
+
+  17. Interpretation of Sections 15 and 16.
+
+  If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+                     END OF TERMS AND CONDITIONS
+
+            How to Apply These Terms to Your New Programs
+
+  If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+  To do so, attach the following notices to the program.  It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+Also add information on how to contact you by electronic and paper mail.
+
+  If the program does terminal interaction, make it output a short
+notice like this when it starts in an interactive mode:
+
+    <program>  Copyright (C) <year>  <name of author>
+    This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+    This is free software, and you are welcome to redistribute it
+    under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License.  Of course, your program's commands
+might be different; for a GUI interface, you would use an "about box".
+
+  You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU GPL, see
+<https://www.gnu.org/licenses/>.
+
+  The GNU General Public License does not permit incorporating your program
+into proprietary programs.  If your program is a subroutine library, you
+may consider it more useful to permit linking proprietary applications with
+the library.  If this is what you want to do, use the GNU Lesser General
+Public License instead of this License.  But first, please read
+<https://www.gnu.org/philosophy/why-not-lgpl.html>.

main.lua

@@ -0,0 +1,21 @@
+-- bootstrap the compiler
+
+local fennel = require("lib.fennel").install({correlate=true,
+                                              moduleName="lib.fennel"})
+
+local make_love_searcher = function(env)
+   return function(module_name)
+      local path = module_name:gsub("%.", "/") .. ".fnl"
+      if love.filesystem.getInfo(path) then
+         return function(...)
+            local code = love.filesystem.read(path)
+            return fennel.eval(code, {env=env}, ...)
+         end, path
+      end
+   end
+end
+
+table.insert(package.loaders, make_love_searcher(_G))
+table.insert(fennel["macro-searchers"], make_love_searcher("_COMPILER"))
+
+require("wrap")

makefile

@@ -0,0 +1,72 @@
+VERSION=0.1.0
+LOVE_VERSION=11.5
+NAME=change-me
+ITCH_ACCOUNT=change-me-too
+URL=https://gitlab.com/alexjgriffith/min-love2d-fennel
+AUTHOR="Your Name"
+DESCRIPTION="Minimal setup for trying out Phil Hagelberg's fennel/love game design process."
+GITHUB_USERNAME := $(shell grep GITHUB_USERNAME credentials.private | cut -d= -f2)
+GITHUB_PAT := $(shell grep GITHUB_PAT credentials.private | cut -d= -f2)
+LIBS := $(wildcard lib/*)
+LUA := $(wildcard *.lua)
+SRC := $(wildcard *.fnl)
+
+run: ; love .
+
+count: ; cloc *.fnl
+
+clean: ; rm -rf releases/*
+
+LOVEFILE=releases/$(NAME)-$(VERSION).love
+
+$(LOVEFILE): $(LUA) $(SRC) $(LIBS) assets
+	mkdir -p releases/
+	find $^ -type f | LC_ALL=C sort | env TZ=UTC zip -r -q -9 -X $@ -@
+
+love: $(LOVEFILE)
+
+# platform-specific distributables
+
+REL=$(PWD)/buildtools/love-release.sh # https://p.hagelb.org/love-release.sh
+FLAGS=-a "$(AUTHOR)" --description $(DESCRIPTION) \
+	--love $(LOVE_VERSION) --url $(URL) --version $(VERSION) --lovefile $(LOVEFILE)
+
+releases/$(NAME)-$(VERSION)-x86_64.AppImage: $(LOVEFILE)
+	cd buildtools/appimage && \
+	./build.sh $(LOVE_VERSION) $(PWD)/$(LOVEFILE) $(GITHUB_USERNAME) $(GITHUB_PAT)
+	mv buildtools/appimage/game-x86_64.AppImage $@
+
+releases/$(NAME)-$(VERSION)-macos.zip: $(LOVEFILE)
+	$(REL) $(FLAGS) -M
+	mv releases/$(NAME)-macos.zip $@
+
+releases/$(NAME)-$(VERSION)-win.zip: $(LOVEFILE)
+	$(REL) $(FLAGS) -W32
+	mv releases/$(NAME)-win32.zip $@
+
+releases/$(NAME)-$(VERSION)-web.zip: $(LOVEFILE)
+	buildtools/love-js/love-js.sh releases/$(NAME)-$(VERSION).love $(NAME) -v=$(VERSION) -a=$(AUTHOR) -o=releases
+
+linux: releases/$(NAME)-$(VERSION)-x86_64.AppImage
+mac: releases/$(NAME)-$(VERSION)-macos.zip
+windows: releases/$(NAME)-$(VERSION)-win.zip
+web: releases/$(NAME)-$(VERSION)-web.zip
+
+
+runweb: $(LOVEFILE)
+	buildtools/love-js/love-js.sh $(LOVEFILE) $(NAME) -v=$(VERSION) -a=$(AUTHOR) -o=releases -r -n
+# If you release on itch.io, you should install butler:
+# https://itch.io/docs/butler/installing.html
+
+uploadlinux: releases/$(NAME)-$(VERSION)-x86_64.AppImage
+	butler push $^ $(ITCH_ACCOUNT)/$(NAME):linux --userversion $(VERSION)
+uploadmac: releases/$(NAME)-$(VERSION)-macos.zip
+	butler push $^ $(ITCH_ACCOUNT)/$(NAME):mac --userversion $(VERSION)
+uploadwindows: releases/$(NAME)-$(VERSION)-win.zip
+	butler push $^ $(ITCH_ACCOUNT)/$(NAME):windows --userversion $(VERSION)
+uploadweb: releases/$(NAME)-$(VERSION)-web.zip
+	butler push $^ $(ITCH_ACCOUNT)/$(NAME):web --userversion $(VERSION)
+
+upload: uploadlinux uploadmac uploadwindows
+
+release: linux mac windows upload cleansrc

mapper.fnl

@@ -0,0 +1,27 @@
+;Generate a map of width by height:
+(fn print_map [map]
+	(for [i 1 (length map)]
+		(var r "")
+		(for [j 1 (length (. map i))]
+			(set r (.. r " " (. map i j))))
+		(print r)))
+
+; Function to generate the map. From here, all additional functions are used.
+(fn generate [height width]
+	(var map [])
+	; Generate the outside shell. This is actually a double-lined outer layer. The
+	; outer-most layer allows for a single-square transitional tile, used as the
+	; entry/exit spot to the map.
+	(for [i 1 (+ height 2)]
+		(tset map i [])
+		(for [j 1 (+ width 2)]
+			(var tile 0) ; By default, draw an empty space
+			(when (or (= i 1) (= i 2) (= i (+ height 1)) (= i (+ height 2))) (set tile 1)) ; The first and last rows
+			(when (or (= j 1) (= j 2) (= j (+ width 1)) (= j (+ width 2))) (set tile 1)) ; The first and last rows
+			(tset map i j tile)))
+	; Add in "set pieces": structures or 
+	map)
+
+ (print_map (generate 20 20))
+
+{: generate}

min-love2d-fennel-readme.org

@@ -0,0 +1,140 @@
+* Minimal Fennel Love2D Setup
+
+In the lead up to the semi-annual [[https://itch.io/jam/autumn-lisp-game-jam-2018][Autumn Lisp Game Jam]] I thought I'd look into Phil Hegelberg's approach to last Aprils Jam, using [[https://love2d.org/][love2d]] in concert with [[https://fennel-lang.org/][fennel]]. Phil outlines his approach on his [[https://technomancy.us/187][blog]].
+
+This repo contains the minimal viable setup to get started with Phil Hegelberg's game design process, plus some additional libraries.
+
+* Alternatives
+This repo is slowly expanding from a truly minimal setup to one that comes with a few batteries included. If you want a barebones setup to get you started check out:
+[[https://sr.ht/~benthor/absolutely-minimal-love2d-fennel/][absolutely-minimal-love2d-fennel]] by @benthor.
+
+If you want to just start coding up some fennel and love with no makefile or manual installation on linux check out [[https://gitlab.com/alexjgriffith/love-fennel][love-fennel]]
+
+* Getting Started
+The following commands will clone this project and duplicate its structure into a new folder =$PROJECT_NAME=
+
+#+BEGIN_SRC bash
+git clone https://gitlab.com/alexjgriffith/min-love2d-fennel.git 
+./min-love2d-fennel/.duplicate/new-game.sh $PROJECT_NAME
+#+END_SRC
+
+Check out the makefile and conf.lua files in =$PROJECT_NAME=, updating them with information relevant to your game.
+
+You can enter =love .= in the =$PROJECT_NAME= directory to run your game, or =make run=. If you are on Windows, using =lovew .= will allow you to use the REPL.
+
+The following lines with =Update= should be changed in the =makefile= and =love.conf= to reflect your game.
+
+#+BEGIN_SRC makefile
+  VERSION=0.1.0
+  LOVE_VERSION=11.4
+  NAME=change-me # Update
+  ITCH_ACCOUNT=change-me-too # Update
+  URL=https://gitlab.com/alexjgriffith/min-love2d-fennel # Update
+  AUTHOR="Your Name" # Update
+  DESCRIPTION="Minimal setup for trying out Phil Hagelberg's fennel/love game design process." # Update
+  GITHUB_USERNAME := $(shell grep GITHUB_USERNAME credentials.private | cut -d= -f2) # Optional (needed for Love V 12.0)
+  GITHUB_PAT := $(shell grep GITHUB_PAT credentials.private | cut -d= -f2) # Optional (needed for Love V 12.0)
+
+#+END_SRC
+
+#+BEGIN_SRC lua
+love.conf = function(t)
+   t.gammacorrect = true
+   t.title, t.identity = "change-me", "Minimal" -- Update
+   t.modules.joystick = false
+   t.modules.physics = false
+   t.window.width = 720
+   t.window.height = 450
+   t.window.vsync = false
+   t.version = "11.4"
+end
+#+END_SRC
+
+* Emacs Setup
+
+Once you install the latest version of [[https://gitlab.com/technomancy/fennel-mode][fennel-mode]], you can run
+=C-u M-x fennel-repl= followed by =love .= to launch a repl.
+
+* Default Project Structure
+
+The =make= process as-is will only compile the contents of the root folder and the =lib/= folder+subfolders, so make sure to put your game files in either of those. 
+
+Specifically, every =.fnl= file needed at runtime needs to be situated in the root folder, and every file which is not a =.lua= or =.fnl= file needs to be put inside =lib/=.
+
+In order to use macros, they have to be put in =.fnl= files inside =lib/=.
+
+* Separate your Code into a /src directory
+
+  If you want a more opinionated layout, you can use pass in a =--layout= parameter when creating your project.
+
+#+BEGIN_SRC bash
+./min-love2d-fennel/.duplicate/new-game.sh $PROJECT_NAME --layout=seperate-source
+#+END_SRC
+
+This build uses =gamestate= rather than Phil's approach to scene separation and puts all your =.fnl= files into a =/src= directory. It also provides a separate makefile that handles this layout. 
+
+Note, any macros will have to be placed in the root of the project or in the =lib= folder (this can be modified in =main.lua=)
+
+Presently the only layouts are =clone= and =seperate-source=. If you want to make your own check out the =.duplicate= directory to see how they work.
+
+* Release Process
+
+Use =make linux=, =make windows=,  =make mac=, or =make web= to create targets for each platform, or =make release= to make all four. Check out the makefile for more commands, and remember to edit your game data in it!
+
+* Adjusting the screen size
+For those of us working with window managers it would be nice if our games behaved while we are developing. Below is code adapted from Phil's 2022 lisp game jam entry [[https://codeberg.org/technomancy/lisp-jam-2022/src/branch/main/wrap.fnl][https://codeberg.org/technomancy/lisp-jam-2022/src/branch/main/wrap.fnl]] . Adapt it to modify your =wrap.fnl= to handle window resizing automatically and adjust your mouse position.
+
+*Note* this is _not a complete solution_. You still need to handle the translation of =love.mouse.getPos= and =love.graphics.inverseTransform=. But, if your game dosn't use those, the snippet below should work out of the box!
+
+#+BEGIN_SRC fennel
+  ;; define the size of your window. From your program's perspective
+  ;; your window will always be this size regardless of size
+  (local window-w 1280)
+  (local window-h 720)
+  (var scale 1)
+  
+  ;; Love provides a handy resize callback. Hook into it to adjust the display size
+  ;; of your window.
+  (fn love.resize [w h]
+    (set scale (math.floor (math.max 1 (math.min (/ w window-w)
+                                                 (/ h window-h))))))
+
+  ;; Changing the display size means that you need to translate from the "display size"
+  ;; to the size your game thinks the window is.
+  (fn love.mousepressed [x y b]
+    (when mode.mousepressed
+      (safely #(mode.mousepressed (/ x scale) (/ y scale) b set-mode))))
+
+  (fn love.mousemoved [x y dx dy istouch]
+    (when mode.mousemoved
+      (safely #(mode.mousemoved (/ x scale) (/ y scale) (/ dx scale) (/ dy scale)
+                                istouch))))
+
+  (fn love.mousereleased [x y b]
+    (when mode.mousereleased
+      (safely #(mode.mousereleased (/ x scale) (/ y scale) b set-mode))))
+
+#+END_SRC
+
+* Targeting the development branch of love (12.0) - LINUX ONLY
+You can target the development branch of love (version 12.0) by setting the `LOVE_VERSION` parameter in the makefile to 12.0. Note that because we are working from a github artifact, rather than a release, you will also have to pass in your github username and a github PAT.
+
+** Getting a PAT
+To download artifacts created by the Github actions CI you will need to get an access token from "settings -> developer settings -> personal access tokens". The token needs `workflow` and `actions:read` permissions.
+
+** Creating a credentials.private file
+By default the makefile looks for `credentials.private` in the root directory of the project. `*.private` is part of `.gitignore` so personal information stored here will not be part of the git history or get pushed to a remote server.
+
+The contents should look something like this:
+#+BEGIN_SRC bash
+GITHUB_USERNAME=username
+GITHUB_PAT=PAT
+#+END_SRC
+
+Note: this is presently linux only, however it may be expanded in the future to cover macos and windows.
+
+* Phil's Modal Callbacks (PMC)
+
+Phil Hegelberg's [[https://gitlab.com/technomancy/exo-encounter-667/][exo-encounter-667]] is structured using a modal callback system. Each game state has a mode and each mode has a series of specific callbacks.
+
+If you design your game as a series of states in a very simple state machine, for example *start-screen*, *play* and *end*, with unidirectional progression, you can easily separate the logic for each state into state/mode specific callbacks. As an example, in order to have state dependant rendering that differs between start-screen,play and end you could provide a *draw* callback for each of those states. Similarly if we need state dependent logic and keyboard input we could provide *update* and *keyboard* callbacks. As you iterate you can add and remove callbacks and states/modes as needed with very little friction.

mode-intro.fnl

@@ -0,0 +1,114 @@
+(local overlay (require :overlay))
+(local state (require :state))
+(local mapper (require :mapper))
+
+(love.graphics.setNewFont 10)
+(local pi math.pi)
+
+(var map (mapper.generate 10 10))
+
+; This sets the wall texture data
+(var walls [])
+(var wall-textures (love.filesystem.getDirectoryItems "textures/walls"))
+
+(each [_ v (ipairs wall-textures)]
+  (local wall {})
+  (tset wall :t (love.graphics.newImage (.. "textures/walls/" v)))
+  (tset wall :w (love.graphics.getWidth (. wall :t)))
+  (tset wall :h (love.graphics.getHeight (. wall :t)))
+  (table.insert walls wall))
+
+; Map size
+(var map-height (length map))
+(var map-width (length (. map 1)))
+
+; Player position and direction
+(var player (state.getPlayer))
+
+; Screen size
+(var (screen-width screen-height) (love.window.getMode))
+; (var screen-width 1280)
+; (var screen-height 720)
+(var texel-width 64)
+(var texel-height 64)
+
+; Ray-casting function
+(fn cast-ray [ray-angle]
+  (local dx (math.cos ray-angle))
+  (local dy (math.sin ray-angle))
+  (var rays [])
+  
+  (var (distance tex done hit-pos) (values 0 1 false {}))
+  (while (not done)
+    (var ray-x (+ player.x (* dx distance)))
+    (var ray-y (+ player.y (* dy distance)))
+    (set rays [ray-x ray-y])
+    
+    ; Check if ray hits a wall (>= 1) on the map
+    (if (or (>= (math.floor ray-x) map-width)
+              (>= (math.floor ray-y) map-height)
+              (<= ray-x 0)
+              (<= ray-y 0)
+              (>= (. map (math.floor ray-y) (math.floor ray-x)) 1))
+      (do 
+        (set done true)
+        (set tex (. map (math.floor ray-y) (math.floor ray-x)))
+        (set hit-pos {:x (- ray-x (math.floor ray-x)) :y (- ray-y (math.floor ray-y))}))
+      ; Increment distance
+      (set distance (+ distance 0.01))))
+
+  (values distance hit-pos tex rays))
+
+; Function to handle player movement
+(fn move-player [move-speed]
+  (let [new-x (+ player.x (* (math.cos player.d) move-speed))
+        new-y (+ player.y (* (math.sin player.d) move-speed))]
+    ; Check for collisions with walls
+    (when (= (. map (math.floor new-y) (math.floor new-x)) 0)
+      (state.modO -1) (state.setX new-x) (state.setY new-y))))
+
+; Draw function for rendering
+{:draw (fn love.draw []
+  (love.graphics.clear)
+  
+  ; For each vertical slice of the screen
+  (var (last-x last-y) (values 0 0))
+  (for [i 0 (- screen-width 1)]
+    ; Calculate angle of ray relative to player direction
+    (local ray-angle (+ player.d (- (* (/ i screen-width) player.f) (/ player.f 2))))
+    
+    ; Cast the ray to find distance to the nearest wall
+    (local (distance hit-pos tex rays) (values (cast-ray ray-angle)))
+    
+    ; Calculate height of the wall slice
+    (local wall-height (math.floor (/ screen-height distance)))
+    (local start-y (/ (- screen-height wall-height) 2))
+    (local end-y (/ (+ screen-height wall-height) 2))
+
+    ; Draw a textured wall
+    (local wall-texture (. walls tex))
+    (var texture-x 0)
+    (if (> (/ (- (. rays 1) last-x) (- (. rays 2) last-y)) (/ (- (. rays 2) last-y) (- (. rays 1) last-x)))
+      (set texture-x (math.floor (* (. hit-pos :y) (. wall-texture :w))))
+      (set texture-x (math.floor (* (. hit-pos :x) (. wall-texture :w)))))
+    (love.graphics.draw (. wall-texture :t)
+                        (love.graphics.newQuad texture-x 0 1 (. wall-texture :h) (. wall-texture :w) (. wall-texture :h))
+                        i start-y 0 1 (/ wall-height (. wall-texture :h)))
+    (when (= 0 (% i 200))
+      (love.graphics.print (.. "r: " ray-angle) i 10)
+      (love.graphics.print (.. "h-x: " (. rays 1)) i 20)
+      (love.graphics.print (.. "h-y: " (. rays 2)) i 30)
+    )
+    (set (last-x last-y) (values (. rays 1) (. rays 2)))
+    )
+
+  (overlay.overlay)
+  (set player (state.getPlayer))
+  )
+
+ :keypressed (fn keypressed [key set-mode]
+      (when (= key "j") (state.setD (- player.d (/ pi 2))))
+      (when (= key "l") (state.setD (+ player.d (/ pi 2))))
+      (when (= key "i") (move-player 1))
+      (when (= key "k") (move-player -1))
+      (when (= key "x") (love.event.quit)))}

notes.md

@@ -0,0 +1,18 @@
+# Notes
+
+## Reminders
+- `wrap.fnl` is the "entrypoint" for the project.
+- Run the project via `make` or `love` (ex: `love .` from base directory)
+
+## Ray-Casting Basics
+Every frame, from left to right, a vertical slice is drawn. The slice can be a
+part of a texture, or a color. Generally, the slice is drawn the full height of
+the wall; half-walls are possible, and presumably so are windows. The slice to
+be drawn is determined by sending a ray from the camera (or camera plane) in the
+facing direction, until the ray intercepts with a wall. The walls, as well as
+most other level details, are provided in a 2-d array, generally of numbers. In
+this example, the number 0 represents open space, and every number above 0
+represents a wall with a specific texture. The initial way of determining the
+ray is using Euclidean geometry, but this can result in a fish-eye lens
+appearance.  Lode's tutorial uses vectors to establish a camera plane from which
+all calculations are performed. This helps reduce the fish-eye appearance.

old-raycaster.fnl

@@ -0,0 +1,114 @@
+(local overlay (require :overlay))
+(local state (require :state))
+(local mapper (require :mapper))
+
+(love.graphics.setNewFont 10)
+(local pi math.pi)
+
+(var map (mapper.generate 10 10))
+
+; This sets the wall texture data
+(var walls [])
+(var wall-textures (love.filesystem.getDirectoryItems "textures/walls"))
+
+(each [_ v (ipairs wall-textures)]
+  (local wall {})
+  (tset wall :t (love.graphics.newImage (.. "textures/walls/" v)))
+  (tset wall :w (love.graphics.getWidth (. wall :t)))
+  (tset wall :h (love.graphics.getHeight (. wall :t)))
+  (table.insert walls wall))
+
+; Map size
+(var map-height (length map))
+(var map-width (length (. map 1)))
+
+; Player position and direction
+(var player (state.getPlayer))
+
+; Screen size
+(var (screen-width screen-height) (love.window.getMode))
+; (var screen-width 1280)
+; (var screen-height 720)
+(var texel-width 64)
+(var texel-height 64)
+
+; Ray-casting function
+(fn cast-ray [ray-angle]
+  (local dx (math.cos ray-angle))
+  (local dy (math.sin ray-angle))
+  (var rays [])
+  
+  (var (distance tex done hit-pos) (values 0 1 false {}))
+  (while (not done)
+    (var ray-x (+ player.x (* dx distance)))
+    (var ray-y (+ player.y (* dy distance)))
+    (set rays [ray-x ray-y])
+    
+    ; Check if ray hits a wall (>= 1) on the map
+    (if (or (>= (math.floor ray-x) map-width)
+              (>= (math.floor ray-y) map-height)
+              (<= ray-x 0)
+              (<= ray-y 0)
+              (>= (. map (math.floor ray-y) (math.floor ray-x)) 1))
+      (do 
+        (set done true)
+        (set tex (. map (math.floor ray-y) (math.floor ray-x)))
+        (set hit-pos {:x (- ray-x (math.floor ray-x)) :y (- ray-y (math.floor ray-y))}))
+      ; Increment distance
+      (set distance (+ distance 0.01))))
+
+  (values distance hit-pos tex rays))
+
+; Function to handle player movement
+(fn move-player [move-speed]
+  (let [new-x (+ player.x (* (math.cos player.d) move-speed))
+        new-y (+ player.y (* (math.sin player.d) move-speed))]
+    ; Check for collisions with walls
+    (when (= (. map (math.floor new-y) (math.floor new-x)) 0)
+      (state.modO -1) (state.setX new-x) (state.setY new-y))))
+
+; Draw function for rendering
+{:draw (fn love.draw []
+  (love.graphics.clear)
+  
+  ; For each vertical slice of the screen
+  (var (last-x last-y) (values 0 0))
+  (for [i 0 (- screen-width 1)]
+    ; Calculate angle of ray relative to player direction
+    (local ray-angle (+ player.d (- (* (/ i screen-width) player.f) (/ player.f 2))))
+    
+    ; Cast the ray to find distance to the nearest wall
+    (local (distance hit-pos tex rays) (values (cast-ray ray-angle)))
+    
+    ; Calculate height of the wall slice
+    (local wall-height (math.floor (/ screen-height distance)))
+    (local start-y (/ (- screen-height wall-height) 2))
+    (local end-y (/ (+ screen-height wall-height) 2))
+
+    ; Draw a textured wall
+    (local wall-texture (. walls tex))
+    (var texture-x 0)
+    (if (> (/ (- (. rays 1) last-x) (- (. rays 2) last-y)) (/ (- (. rays 2) last-y) (- (. rays 1) last-x)))
+      (set texture-x (math.floor (* (. hit-pos :y) (. wall-texture :w))))
+      (set texture-x (math.floor (* (. hit-pos :x) (. wall-texture :w)))))
+    (love.graphics.draw (. wall-texture :t)
+                        (love.graphics.newQuad texture-x 0 1 (. wall-texture :h) (. wall-texture :w) (. wall-texture :h))
+                        i start-y 0 1 (/ wall-height (. wall-texture :h)))
+    (when (= 0 (% i 200))
+      (love.graphics.print (.. "r: " ray-angle) i 10)
+      (love.graphics.print (.. "h-x: " (. rays 1)) i 20)
+      (love.graphics.print (.. "h-y: " (. rays 2)) i 30)
+    )
+    (set (last-x last-y) (values (. rays 1) (. rays 2)))
+    )
+
+  (overlay.overlay)
+  (set player (state.getPlayer))
+  )
+
+ :keypressed (fn keypressed [key set-mode]
+      (when (= key "j") (state.setD (- player.d (/ pi 2))))
+      (when (= key "l") (state.setD (+ player.d (/ pi 2))))
+      (when (= key "i") (move-player 1))
+      (when (= key "k") (move-player -1))
+      (when (= key "x") (love.event.quit)))}

overlay.fnl

@@ -0,0 +1,63 @@
+; Draw the overlay
+; Relies on information about the player and the display
+(local player (require :state))
+(var screen-width 1280)
+(var screen-height 720)
+
+; This draws the oxygen ui
+; Sequential blocks, up to 10; each block 10%
+(fn oxygen-ui [x y]
+  (local (bx by bb o) (values 10 10 15 (player.getO)))
+  (local bn (math.floor (/ o 10)))
+  (var (dx dy) (values 0 50))
+  (local bp (* 5 (% o 10)))
+  (love.graphics.setColor 0 1 0 0.25)
+  (for [i 1 10]
+    (love.graphics.polygon "line" (+ x dx 1) (+ y by 1)
+                                  (+ x dx bx 1) (+ y by 1)
+                                  (+ x dx bx 1) (+ y by dy 1)
+                                  (+ x dx 1) (+ y by dy 1))
+    (if (<= i bn)
+      (love.graphics.polygon "fill" (+ x dx) (+ y by)
+                                    (+ x dx bx) (+ y by)
+                                    (+ x dx bx) (+ y by dy)
+                                    (+ x dx) (+ y by dy)))
+    (if (= i (+ bn 1))
+      (love.graphics.polygon "fill" (+ x dx) (+ y (- (+ dy by) bp))
+                                    (+ x dx bx) (+ y (- (+ dy by) bp))
+                                    (+ x dx bx) (+ y by dy)
+                                    (+ x dx) (+ y by dy)))
+    (set dx (+ dx bb))))
+
+; This draws the power ui
+; Inverse-sequential blocks, up to 10; each block 10%
+(fn power-ui [x y]
+  (local (bx by bb p) (values 10 10 15 (player.getP)))
+  (local bn (math.floor (/ p 10)))
+  (var (dx dy) (values 0 50))
+  (local bp (* 5 (% p 10)))
+  (love.graphics.setColor 1 1 0 0.25)
+  (for [i 1 10]
+    (love.graphics.polygon "line" (- x dx 1) (+ y by 1)
+                                  (- x dx bx 1) (+ y by 1)
+                                  (- x dx bx 1) (+ y by dy 1)
+                                  (- x dx 1) (+ y by dy 1))
+    (if (<= i bn)
+      (love.graphics.polygon "fill" (- x dx) (+ y by)
+                                    (- x dx bx) (+ y by)
+                                    (- x dx bx) (+ y by dy)
+                                    (- x dx) (+ y by dy)))
+    (if (= i (+ bn 1))
+      (love.graphics.polygon "fill" (- x dx) (+ y (- (+ dy by) bp))
+                                    (- x dx bx) (+ y (- (+ dy by) bp))
+                                    (- x dx bx) (+ y by dy)
+                                    (- x dx) (+ y by dy)))
+    (set dx (+ dx bb))))
+
+(fn overlay []
+  (oxygen-ui (+ (/ screen-width 2) 100) (- screen-height 100))
+  (power-ui (- (/ screen-width 2) 100) (- screen-height 100))
+  (love.graphics.setColor 1 1 1)
+)
+
+{: overlay}

ray-cast-vectors.fnl

@@ -0,0 +1,132 @@
+; Much of this is derived from https://lodev.org/cgtutor/raycasting.html
+(local pi math.pi)
+(love.graphics.setColor 1 1 1)
+(love.graphics.setNewFont 30)
+
+; Define map (0 is empty space, 1 is wall)
+(var map [[1 1 1 1 1 ]
+          [2 0 0 0 4 ]
+          [2 0 0 0 4 ]
+          [2 0 0 0 4 ]
+          [1 3 3 3 1 ]])
+
+; This sets the wall texture data
+(var walls [])
+(var wall-textures (love.filesystem.getDirectoryItems "textures/walls"))
+
+(each [_ v (ipairs wall-textures)]
+  (local wall {})
+  (tset wall :t (love.graphics.newImage (.. "textures/walls/" v)))
+  (tset wall :w (love.graphics.getWidth (. wall :t)))
+  (tset wall :h (love.graphics.getHeight (. wall :t)))
+  (table.insert walls wall))
+
+; Map size
+(var map-height (length map))
+(var map-width (length (. map 1)))
+
+; Player position and direction
+; pos{x,y}: position vector of the player
+; dir{x,y}: direction vector of the player
+; pln{x,y}: camera plane of the player
+(var player {:posx 3 :posy 3
+             :dirx -1 :diry 0
+             :plnx 0 :plny 0.66})
+
+; Screen size
+(var screen-width 1920)
+(var screen-height 1080)
+(var texel-width 64)
+(var texel-height 64)
+
+; Function to handle player movement
+(fn move-player [move-speed]
+  (let [new-x (+ player.posx (* (math.cos player.dir) move-speed))
+        new-y (+ player.y (* (math.sin player.dir) move-speed))]
+    ; Check for collisions with walls
+    (when (= (. map (math.floor new-y) (math.floor new-x)) 0)
+      (set player.x new-x)
+      (set player.y new-y))))
+
+; Function to handle player rotation
+(fn rotate-player [rot]
+  (local (o-dx o-px) (values player.dirx player.plnx))
+  (set player.dirx (- (* player.dirx (math.cos rot)) (* player.diry (math.sin rot))))
+  (set player.plnx (- (* player.plnx (math.cos rot)) (* player.plny (math.sin rot))))
+  (set player.diry (+ (* o-dx (math.sin rot)) (* player.diry (math.cos rot))))
+  (set player.plny (+ (* o-px (math.sin rot)) (* player.plny (math.cos rot))))
+)
+
+; Draw function for rendering
+{:draw (fn love.draw []
+  (love.graphics.clear)
+  
+  ; For each vertical slice of the screen
+  (for [i 0 (- screen-width 1)]
+    ; Setup a bunch of variables
+    ; Camera Space x-coordinate, kind of the ray position
+    (local cam-x (- (/ (* 2 i) screen-width) 1))
+    ; Ray direction vector values
+    (local (ray-dir-x ray-dir-y) (values (+ player.dirx (* player.plnx cam-x)) (+ player.diry (* player.plny cam-x)))) 
+    ; Current player position on the map grid
+    (var (map-x map-y) (values (math.floor player.posx) (math.floor player.posy)))
+    ; Length of ray from first x/y to the next x/y
+    (local (delta-dist-x delta-dist-y) (values 
+                                         (math.sqrt (+ 1 (/ (* ray-dir-y ray-dir-y) (* ray-dir-x ray-dir-x))))
+                                         (math.sqrt (+ 1 (/ (* ray-dir-x ray-dir-x) (* ray-dir-y ray-dir-y))))))
+    ; Side hit (n/s or e/w)
+    (var side nil)
+    ; Calculate step and distance from player to first x/y-side (as per Love graphics grid)
+    (var (step-x side-dist-x) (if (< ray-dir-x 0) 
+                                (values -1 (* (- player.posx map-x) delta-dist-x))
+                                (values 1 (* (- player.posx (+ map-x 1)) delta-dist-x))))
+    (var (step-y side-dist-y) (if (< ray-dir-y 0) 
+                                (values -1 (* (- player.posy map-y) delta-dist-y))
+                                (values 1 (* (- player.posy (+ map-y 1)) delta-dist-y))))
+    ; Shoot ze ray until it hits something
+    (var wall-hit false)
+    (while (not wall-hit)
+      (if (< side-dist-x side-dist-y)
+        (set (side-dist-x map-x side) (values (+ side-dist-x delta-dist-x) (+ map-x step-x) 0))
+        (set (side-dist-y map-y side) (values (+ side-dist-y delta-dist-y) (+ map-y step-y) 1)))
+      (set wall-hit (if (> (. map map-x map-y) 0) true false)))
+    ; Set the perpindicular length from the camera plane to the wall
+    (var ray-length (if (= side 0) (- side-dist-x delta-dist-x) (- side-dist-y delta-dist-y)))
+    ; Determine pixel-column height
+    (var line-height (math.floor (/ screen-height ray-length)))
+    (var (draw-start draw-end) (values (+ (/ (* -1 line-height) 2) (/ screen-height 2)) (+ (/ line-height 2) (/ screen-height 2))))
+    (if (< draw-start 0) (set draw-start 0))
+    (if (>= draw-end screen-height) (set draw-end (- screen-height 1)))
+    ; Determine exactly where along the wall the ray hits
+    (var wall-col (if (= side 0) (+ player.posy (* ray-length ray-dir-y)) (+ player.posx (* ray-length ray-dir-x))))
+    (set wall-col (- wall-col (math.floor wall-col)))
+    ; Select the texture data based on the grid number
+    (local wall-texture (. walls (. map map-x map-y)))
+    ; Calculate the part of the texture to paint, and then do so
+    (var texture-x (math.floor (* wall-col (. wall-texture :w))))
+    (if (and (= side 0) (> ray-dir-x 0)) (set texture-x (- (- (. wall-texture :w) texture-x) 1)))
+    (if (and (= side 1) (< ray-dir-y 0)) (set texture-x (- (- (. wall-texture :w) texture-x) 1)))
+    (love.graphics.setColor 1 1 1)
+    (love.graphics.draw (. wall-texture :t)
+                        (love.graphics.newQuad texture-x 0 1 (. wall-texture :h) (. wall-texture :w) (. wall-texture :h))
+                        i draw-start 0 1 (/ line-height (. wall-texture :h)))
+    ; Draw simple lines
+    ; (love.graphics.line i draw-start i draw-end)
+    (love.graphics.setColor 1 0 0)
+    (love.graphics.print (.. "player-x: " player.posx ", player-y:" player.posy) 50 300)
+    (love.graphics.print (.. "map-x: " map-x ", map-y:" map-y ", val:" (. map map-x map-y)) 50 330)
+    (love.graphics.print (.. "side: " side ", ray-length:" ray-length) 50 370)
+    (love.graphics.print (.. "step-x: " step-x ", step-y:" step-y) 50 400)
+    )
+  )
+
+ :update (fn update [dt]
+      (when (love.keyboard.isDown "j") (rotate-player 0.1))
+      (when (love.keyboard.isDown "l") (rotate-player -0.1)))
+
+ :keypressed (fn keypressed [key set-mode]
+      (when (= key "j") (rotate-player 0.05))
+      (when (= key "l") (rotate-player -0.05))
+      (when (= key "i") (move-player 1))
+      (when (= key "k") (move-player -1))
+      (when (= key "x") (love.event.quit)))}

ray-cast.fnl

@@ -0,0 +1,61 @@
+(local pi (math.pi))
+
+; Define map (0 is empty space, 1 is wall)
+(var map [[1 1 1 1 1]
+          [1 0 0 0 1]
+          [1 0 1 0 1]
+          [1 0 0 0 1]
+          [1 1 1 1 1]])
+
+; Map size
+(var map-width (length map))
+(var map-height (length (first map)))
+
+; Player position and direction
+(var player {:x 2.5 :y 2.5 :dir 0 :fov (/ pi 3)})
+
+; Screen size
+(var screen-width 640)
+(var screen-height 480)
+
+; Ray-casting function
+(fn cast-ray [ray-angle]
+  (local dx (math.cos ray-angle))
+  (local dy (math.sin ray-angle))
+  
+  (var distance 0)
+  (while true
+    (var ray-x (+ player.x (* dx distance)))
+    (var ray-y (+ player.y (* dy distance)))
+    
+    ; Check if ray hits a wall (1) on the map
+    (when (or (>= (math.floor ray-x) map-width)
+              (>= (math.floor ray-y) map-height)
+              (<= ray-x 0)
+              (<= ray-y 0)
+              (= (nth (nth map (math.floor ray-y)) (math.floor ray-x)) 1))
+      (return distance))
+    
+    ; Increment distance
+    (set distance (+ distance 0.01))))
+
+; Draw function for rendering
+(fn love.draw []
+  (love.graphics.clear)
+  
+  ; For each vertical slice of the screen
+  (for [i 0 (- screen-width 1)]
+    ; Calculate angle of ray relative to player direction
+    (local ray-angle (+ player.dir
+                        (- (* (/ i screen-width) player.fov) (/ player.fov 2))))
+    
+    ; Cast the ray to find distance to the nearest wall
+    (local distance (cast-ray ray-angle))
+    
+    ; Calculate height of the wall slice
+    (local wall-height (math.floor (/ screen-height distance)))
+    
+    ; Draw the wall slice (centered vertically)
+    (love.graphics.line i (/ (- screen-height wall-height) 2)
+                        i (/ (+ screen-height wall-height) 2))))
+

raycaster.fnl

@@ -0,0 +1,206 @@
+(local state (require :state))
+(local mapper (require :mapper))
+(local overlay (require :overlay))
+(local pi math.pi)
+; ### Screen Size ###
+(var (screen-width screen-height) (love.window.getMode))
+
+; ### Map Information ###
+(var map (mapper.generate 15 15))
+; (var map [[1 1 1 1 1 1 1 1 1 1 1 ]
+;           [2 0 0 0 0 0 0 0 0 0 4 ]
+;           [2 0 0 0 0 0 0 0 0 0 4 ]
+;           [2 0 0 0 0 0 0 0 0 0 4 ]
+;           [2 0 0 0 0 0 0 0 0 0 4 ]
+;           [2 0 0 0 0 0 0 0 0 0 4 ]
+;           [2 0 0 0 0 0 0 0 3 0 4 ]
+;           [2 0 0 0 0 0 0 3 3 0 4 ]
+;           [2 0 0 0 0 0 0 0 0 0 4 ]
+;           [1 1 1 1 1 1 1 1 1 1 1 ]])
+
+; ### Texture Information ###
+(var walls [])
+(var wall-textures (love.filesystem.getDirectoryItems "textures/walls"))
+(var (tex-height tex-width) (values 64 64))
+
+(each [_ v (ipairs wall-textures)]
+  (local wall {})
+  (tset wall :t (love.graphics.newImage (.. "textures/walls/" v)))
+  (tset wall :w (love.graphics.getWidth (. wall :t)))
+  (tset wall :h (love.graphics.getHeight (. wall :t)))
+  (table.insert walls wall))
+
+; ### "Player" variables ###
+(var (posx posy) (values 4.0 4.0))      ; Initial map position
+(var (dirx diry) (values -1.0 0.0))     ; Initial direction vector
+(var (planex planey) (values 0 0.80))   ; Camera plane
+
+{
+  :draw (fn love.draw []
+    (for [i 0 screen-width]
+      ; Calculate ray position and direction
+      ; Originals, giving a fish-eye lens effect:
+      ; (var camerax (/ (* 2 i) (- screen-width 1)))
+      ; (var (ray-dir-x ray-dir-y) (values (+ dirx (* planex camerax)) (+ diry (* planey camerax))))
+      (var camerax (/ (* 2 i) (- screen-width 1)))
+      (var (ray-dir-x ray-dir-y) (values (+ dirx (* planex camerax)) (+ diry (* planey camerax))))
+
+      ; Which map square we're in
+      (var (mapx mapy) (values (math.floor posx) (math.floor posy)))
+
+      ; Length of ray from current position to next x or y side
+      (var (side-dist-x side-dist-y) (values 0 0))
+
+      ; Length of ray from one x or y side to the next x or y side
+      ; (var (delta-dist-x delta-dist-y) (values 
+      ;                                      (math.sqrt (+ 1 (/ (* ray-dir-y ray-dir-y) (* ray-dir-x ray-dir-x))))
+      ;                                      (math.sqrt (+ 1 (/ (* ray-dir-x ray-dir-x) (* ray-dir-y ray-dir-y))))))
+      (var (delta-dist-x delta-dist-y) (values (math.abs (/ 1 ray-dir-x)) (math.abs (/ 1 ray-dir-y))))
+
+      (var perp-wall-dist 0)
+
+      ; Direction to step in, x or y
+      (var (stepx stepy) (values 0 0))
+
+      ; Side the ray hits, x (0) or y (1)
+      (var side 0)
+
+      ; Calculate step and initial side-dist-*
+      (if (< ray-dir-x 0)
+        (do
+          (set stepx -1)
+          (set side-dist-x (* (- posx mapx) delta-dist-x)))
+        (do
+          (set stepx 1)
+          (set side-dist-x (* (- (+ mapx 1.0) posx) delta-dist-x))))
+      (if (< ray-dir-y 0)
+        (do
+          (set stepy -1)
+          (set side-dist-y (* (- posy mapy) delta-dist-y)))
+        (do
+          (set stepy 1)
+          (set side-dist-y (* (- (+ mapy 1.0) posy) delta-dist-y))))
+
+      ; Perform DDA (Digital Differential Analysis)
+      (var hit false)
+      (while (not hit)
+        (if (< side-dist-x side-dist-y)
+          (do
+            (set side-dist-x (+ side-dist-x delta-dist-x))
+            (set mapx (+ mapx stepx))
+            (set side 0))
+          (do
+            (set side-dist-y (+ side-dist-y delta-dist-y))
+            (set mapy (+ mapy stepy))
+            (set side 1)))
+        (if (> (. map mapx mapy) 0) (set hit true)))
+
+      ; Calculate distance of perpendicular ray, to avoid fisheye effect
+      (if (= side 0)
+        (set perp-wall-dist (- side-dist-x delta-dist-x))
+        (set perp-wall-dist (- side-dist-y delta-dist-y)))
+
+      ; Calculate height of line to draw on screen
+      (var line-height (/ screen-height perp-wall-dist))
+
+      ; Calculate lowest and highest pixel to fill in current stripe
+      (var draw-start (+ (/ (- line-height) 2) (/ screen-height 2)))
+      (if (< draw-start 0) (set draw-start 0))
+      (var draw-end (+ (/ line-height 2) (/ screen-height 2)))
+      (if (>= draw-end screen-height) (set draw-end (- screen-height 1)))
+
+      ; Draw wall slice
+      ; (var color [1 1 1 1])
+      ; (case (. map mapx mapy)
+      ;   1 (set color [1 1 1 1])
+      ;   2 (set color [1 0 0 1])
+      ;   3 (set color [0 1 0 1])
+      ;   4 (set color [0 0 1 1])
+      ; )
+
+      ; (when (= side 1)
+      ;   (tset color 1 (/ (. color 1) 2))
+      ;   (tset color 2 (/ (. color 2) 2))
+      ;   (tset color 3 (/ (. color 3) 2)))
+
+      ; (love.graphics.setColor color)
+      ; (love.graphics.line i draw-start i draw-end)
+      ; (love.graphics.setColor 1 1 1)
+
+      ; Draw textured wall
+      ;; Choose texture
+      (var tex-num (. walls (. map mapx mapy)))
+      ;; Calculate exactly where the wall was hit
+      (var wallx 0)
+      (if (= side 0)
+        (set wallx (+ posy (* perp-wall-dist ray-dir-y)))
+        (set wallx (+ posx (* perp-wall-dist ray-dir-x))))
+      (set wallx (- wallx (math.floor wallx)))
+      ;; Find the x-coordinate on the texture
+      (var tex-x (math.floor (* wallx (. tex-num :w))))
+      (if (and (= side 0) (> ray-dir-x 0)) (set tex-x (- (. tex-num :w) tex-x 1)))
+      (if (and (= side 1) (< ray-dir-y 0)) (set tex-x (- (. tex-num :w) tex-x 1)))
+      ;; Draw the texture
+      (love.graphics.draw (. tex-num :t)
+                          (love.graphics.newQuad tex-x 0 1 (. tex-num :h) (. tex-num :w) (. tex-num :h))
+                          i draw-start 0 1 (/ line-height (. tex-num :h)))
+    )
+
+    (overlay.overlay)
+  )
+
+  :update (fn update [dt]
+    (var mvspeed (* dt 3.0))
+    (var rtspeed (* dt 1.0))
+
+    (when (love.keyboard.isDown "up")
+      (when (= 0 (. map (math.floor (+ (* mvspeed dirx) posx)) (math.floor posy)))
+        (set posx (+ (* mvspeed dirx) posx)))
+      (when (= 0 (. map (math.floor posx) (math.floor (+ (* mvspeed diry) posy))))
+        (set posy (+ (* mvspeed diry) posy)))
+    )
+
+    (when (love.keyboard.isDown "down")
+      (when (= 0 (. map (math.floor (+ (* mvspeed dirx) posx)) (math.floor posy)))
+        (set posx (- posx (* mvspeed dirx))))
+      (when (= 0 (. map (math.floor posx) (math.floor (+ (* mvspeed diry) posy))))
+        (set posy (- posy (* mvspeed diry))))
+    )
+
+    (when (love.keyboard.isDown "right")
+      (var old-dirx dirx)
+      (set dirx (- (* dirx (math.cos (- rtspeed))) (* diry (math.sin (- rtspeed)))))
+      (set diry (+ (* old-dirx (math.sin (- rtspeed))) (* diry (math.cos (- rtspeed)))))
+      (var old-planex planex)
+      (set planex (- (* planex (math.cos (- rtspeed))) (* planey (math.sin (- rtspeed)))))
+      (set planey (+ (* old-planex (math.sin (- rtspeed))) (* planey (math.cos (- rtspeed)))))
+    )
+
+    (when (love.keyboard.isDown "left")
+      (var old-dirx dirx)
+      (set dirx (- (* dirx (math.cos rtspeed)) (* diry (math.sin rtspeed))))
+      (set diry (+ (* old-dirx (math.sin rtspeed)) (* diry (math.cos rtspeed))))
+      (var old-planex planex)
+      (set planex (- (* planex (math.cos rtspeed)) (* planey (math.sin rtspeed))))
+      (set planey (+ (* old-planex (math.sin rtspeed)) (* planey (math.cos rtspeed))))
+    )
+  )
+
+  :keypressed (fn keypressed [k]
+    (when (= k "x") (love.event.quit))                
+  )
+}
+
+; (fn move-player [x]
+;   (let [new-x (+ posx (* (math.cos dirx)) x) new-y (+ posy (* (math.sin diry)) x)]
+;     (when (= (. map (math.floor new-y) (math.floor new-x)) 0)
+;       (set posx new-x) (set posy new-y))))
+
+; (fn rotate-player [d]
+;   (local rotation-speed 1)
+;   (var old-dirx dirx)
+;   (set dirx (- (* dirx (math.cos (* d rotation-speed))) (* diry (math.sin (* d rotation-speed)))))
+;   (set diry (+ (* old-dirx (math.sin (* d rotation-speed))) (* diry (math.cos (* d rotation-speed)))))
+;   (var old-planex planex)
+;   (set planex (- (* planex (math.cos (* d rotation-speed))) (* planey (math.sin (* d rotation-speed)))))
+;   (set planey (+ (* old-planex (math.sin (* d rotation-speed))) (* planey (math.cos (* d rotation-speed))))))

raycaster_flat.cpp

@@ -0,0 +1,242 @@
+/*
+Copyright (c) 2004-2021, Lode Vandevenne
+
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
+
+    * Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
+    * Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+#include <cmath>
+#include <string>
+#include <vector>
+#include <iostream>
+
+#include "quickcg.h"
+using namespace QuickCG;
+
+/*
+g++ *.cpp -lSDL -O3 -W -Wall -ansi -pedantic
+g++ *.cpp -lSDL
+*/
+
+//place the example code below here:
+
+#define screenWidth 640
+#define screenHeight 480
+#define mapWidth 24
+#define mapHeight 24
+
+int worldMap[mapWidth][mapHeight]=
+{
+  {1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1},
+  {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
+  {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
+  {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
+  {1,0,0,0,0,0,2,2,2,2,2,0,0,0,0,3,0,3,0,3,0,0,0,1},
+  {1,0,0,0,0,0,2,0,0,0,2,0,0,0,0,0,0,0,0,0,0,0,0,1},
+  {1,0,0,0,0,0,2,0,0,0,2,0,0,0,0,3,0,0,0,3,0,0,0,1},
+  {1,0,0,0,0,0,2,0,0,0,2,0,0,0,0,0,0,0,0,0,0,0,0,1},
+  {1,0,0,0,0,0,2,2,0,2,2,0,0,0,0,3,0,3,0,3,0,0,0,1},
+  {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
+  {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
+  {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
+  {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
+  {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
+  {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
+  {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
+  {1,4,4,4,4,4,4,4,4,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
+  {1,4,0,4,0,0,0,0,4,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
+  {1,4,0,0,0,0,5,0,4,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
+  {1,4,0,4,0,0,0,0,4,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
+  {1,4,0,4,4,4,4,4,4,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
+  {1,4,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
+  {1,4,4,4,4,4,4,4,4,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
+  {1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1}
+};
+
+int main(int /*argc*/, char */*argv*/[])
+{
+  double posX = 22, posY = 12;  //x and y start position
+  double dirX = -1, dirY = 0; //initial direction vector
+  double planeX = 0, planeY = 0.66; //the 2d raycaster version of camera plane
+
+  double time = 0; //time of current frame
+  double oldTime = 0; //time of previous frame
+
+  screen(screenWidth, screenHeight, 0, "Raycaster");
+  while(!done())
+  {
+    for(int x = 0; x < w; x++)
+    {
+      //calculate ray position and direction
+      double cameraX = 2 * x / (double)w - 1; //x-coordinate in camera space
+      double rayDirX = dirX + planeX * cameraX;
+      double rayDirY = dirY + planeY * cameraX;
+      //which box of the map we're in
+      int mapX = int(posX);
+      int mapY = int(posY);
+
+      //length of ray from current position to next x or y-side
+      double sideDistX;
+      double sideDistY;
+
+      //length of ray from one x or y-side to next x or y-side
+      //these are derived as:
+      //deltaDistX = sqrt(1 + (rayDirY * rayDirY) / (rayDirX * rayDirX))
+      //deltaDistY = sqrt(1 + (rayDirX * rayDirX) / (rayDirY * rayDirY))
+      //which can be simplified to abs(|rayDir| / rayDirX) and abs(|rayDir| / rayDirY)
+      //where |rayDir| is the length of the vector (rayDirX, rayDirY). Its length,
+      //unlike (dirX, dirY) is not 1, however this does not matter, only the
+      //ratio between deltaDistX and deltaDistY matters, due to the way the DDA
+      //stepping further below works. So the values can be computed as below.
+      // Division through zero is prevented, even though technically that's not
+      // needed in C++ with IEEE 754 floating point values.
+      double deltaDistX = (rayDirX == 0) ? 1e30 : std::abs(1 / rayDirX);
+      double deltaDistY = (rayDirY == 0) ? 1e30 : std::abs(1 / rayDirY);
+
+      double perpWallDist;
+
+      //what direction to step in x or y-direction (either +1 or -1)
+      int stepX;
+      int stepY;
+
+      int hit = 0; //was there a wall hit?
+      int side; //was a NS or a EW wall hit?
+      //calculate step and initial sideDist
+      if(rayDirX < 0)
+      {
+        stepX = -1;
+        sideDistX = (posX - mapX) * deltaDistX;
+      }
+      else
+      {
+        stepX = 1;
+        sideDistX = (mapX + 1.0 - posX) * deltaDistX;
+      }
+      if(rayDirY < 0)
+      {
+        stepY = -1;
+        sideDistY = (posY - mapY) * deltaDistY;
+      }
+      else
+      {
+        stepY = 1;
+        sideDistY = (mapY + 1.0 - posY) * deltaDistY;
+      }
+      //perform DDA
+      while(hit == 0)
+      {
+        //jump to next map square, either in x-direction, or in y-direction
+        if(sideDistX < sideDistY)
+        {
+          sideDistX += deltaDistX;
+          mapX += stepX;
+          side = 0;
+        }
+        else
+        {
+          sideDistY += deltaDistY;
+          mapY += stepY;
+          side = 1;
+        }
+        //Check if ray has hit a wall
+        if(worldMap[mapX][mapY] > 0) hit = 1;
+      }
+      //Calculate distance projected on camera direction. This is the shortest distance from the point where the wall is
+      //hit to the camera plane. Euclidean to center camera point would give fisheye effect!
+      //This can be computed as (mapX - posX + (1 - stepX) / 2) / rayDirX for side == 0, or same formula with Y
+      //for size == 1, but can be simplified to the code below thanks to how sideDist and deltaDist are computed:
+      //because they were left scaled to |rayDir|. sideDist is the entire length of the ray above after the multiple
+      //steps, but we subtract deltaDist once because one step more into the wall was taken above.
+      if(side == 0) perpWallDist = (sideDistX - deltaDistX);
+      else          perpWallDist = (sideDistY - deltaDistY);
+
+      //Calculate height of line to draw on screen
+      int lineHeight = (int)(h / perpWallDist);
+
+      //calculate lowest and highest pixel to fill in current stripe
+      int drawStart = -lineHeight / 2 + h / 2;
+      if(drawStart < 0) drawStart = 0;
+      int drawEnd = lineHeight / 2 + h / 2;
+      if(drawEnd >= h) drawEnd = h - 1;
+
+      //choose wall color
+      ColorRGB color;
+      switch(worldMap[mapX][mapY])
+      {
+        case 1:  color = RGB_Red;    break; //red
+        case 2:  color = RGB_Green;  break; //green
+        case 3:  color = RGB_Blue;   break; //blue
+        case 4:  color = RGB_White;  break; //white
+        default: color = RGB_Yellow; break; //yellow
+      }
+
+      //give x and y sides different brightness
+      if(side == 1) {color = color / 2;}
+
+      //draw the pixels of the stripe as a vertical line
+      verLine(x, drawStart, drawEnd, color);
+    }
+    //timing for input and FPS counter
+    oldTime = time;
+    time = getTicks();
+    double frameTime = (time - oldTime) / 1000.0; //frameTime is the time this frame has taken, in seconds
+    print(1.0 / frameTime); //FPS counter
+    redraw();
+    cls();
+
+    //speed modifiers
+    double moveSpeed = frameTime * 5.0; //the constant value is in squares/second
+    double rotSpeed = frameTime * 3.0; //the constant value is in radians/second
+    readKeys();
+    //move forward if no wall in front of you
+    if(keyDown(SDLK_UP))
+    {
+      if(worldMap[int(posX + dirX * moveSpeed)][int(posY)] == false) posX += dirX * moveSpeed;
+      if(worldMap[int(posX)][int(posY + dirY * moveSpeed)] == false) posY += dirY * moveSpeed;
+    }
+    //move backwards if no wall behind you
+    if(keyDown(SDLK_DOWN))
+    {
+      if(worldMap[int(posX - dirX * moveSpeed)][int(posY)] == false) posX -= dirX * moveSpeed;
+      if(worldMap[int(posX)][int(posY - dirY * moveSpeed)] == false) posY -= dirY * moveSpeed;
+    }
+    //rotate to the right
+    if(keyDown(SDLK_RIGHT))
+    {
+      //both camera direction and camera plane must be rotated
+      double oldDirX = dirX;
+      dirX = dirX * cos(-rotSpeed) - dirY * sin(-rotSpeed);
+      dirY = oldDirX * sin(-rotSpeed) + dirY * cos(-rotSpeed);
+      double oldPlaneX = planeX;
+      planeX = planeX * cos(-rotSpeed) - planeY * sin(-rotSpeed);
+      planeY = oldPlaneX * sin(-rotSpeed) + planeY * cos(-rotSpeed);
+    }
+    //rotate to the left
+    if(keyDown(SDLK_LEFT))
+    {
+      //both camera direction and camera plane must be rotated
+      double oldDirX = dirX;
+      dirX = dirX * cos(rotSpeed) - dirY * sin(rotSpeed);
+      dirY = oldDirX * sin(rotSpeed) + dirY * cos(rotSpeed);
+      double oldPlaneX = planeX;
+      planeX = planeX * cos(rotSpeed) - planeY * sin(rotSpeed);
+      planeY = oldPlaneX * sin(rotSpeed) + planeY * cos(rotSpeed);
+    }
+  }
+}

raycaster_textured.cpp

@@ -0,0 +1,291 @@
+/*
+Copyright (c) 2004-2019, Lode Vandevenne
+
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
+
+    * Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
+    * Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+#include <cmath>
+#include <string>
+#include <vector>
+#include <iostream>
+
+#include "quickcg.h"
+using namespace QuickCG;
+
+/*
+g++ *.cpp -lSDL -O3 -W -Wall -ansi -pedantic
+g++ *.cpp -lSDL
+*/
+
+
+#define screenWidth 640
+#define screenHeight 480
+#define texWidth 64
+#define texHeight 64
+#define mapWidth 24
+#define mapHeight 24
+
+int worldMap[mapWidth][mapHeight]=
+{
+  {4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,7,7,7,7,7,7,7,7},
+  {4,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,7,0,0,0,0,0,0,7},
+  {4,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,7},
+  {4,0,2,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,7},
+  {4,0,3,0,0,0,0,0,0,0,0,0,0,0,0,0,7,0,0,0,0,0,0,7},
+  {4,0,4,0,0,0,0,5,5,5,5,5,5,5,5,5,7,7,0,7,7,7,7,7},
+  {4,0,5,0,0,0,0,5,0,5,0,5,0,5,0,5,7,0,0,0,7,7,7,1},
+  {4,0,6,0,0,0,0,5,0,0,0,0,0,0,0,5,7,0,0,0,0,0,0,8},
+  {4,0,7,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,7,7,7,1},
+  {4,0,8,0,0,0,0,5,0,0,0,0,0,0,0,5,7,0,0,0,0,0,0,8},
+  {4,0,0,0,0,0,0,5,0,0,0,0,0,0,0,5,7,0,0,0,7,7,7,1},
+  {4,0,0,0,0,0,0,5,5,5,5,0,5,5,5,5,7,7,7,7,7,7,7,1},
+  {6,6,6,6,6,6,6,6,6,6,6,0,6,6,6,6,6,6,6,6,6,6,6,6},
+  {8,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,4},
+  {6,6,6,6,6,6,0,6,6,6,6,0,6,6,6,6,6,6,6,6,6,6,6,6},
+  {4,4,4,4,4,4,0,4,4,4,6,0,6,2,2,2,2,2,2,2,3,3,3,3},
+  {4,0,0,0,0,0,0,0,0,4,6,0,6,2,0,0,0,0,0,2,0,0,0,2},
+  {4,0,0,0,0,0,0,0,0,0,0,0,6,2,0,0,5,0,0,2,0,0,0,2},
+  {4,0,0,0,0,0,0,0,0,4,6,0,6,2,0,0,0,0,0,2,2,0,2,2},
+  {4,0,6,0,6,0,0,0,0,4,6,0,0,0,0,0,5,0,0,0,0,0,0,2},
+  {4,0,0,5,0,0,0,0,0,4,6,0,6,2,0,0,0,0,0,2,2,0,2,2},
+  {4,0,6,0,6,0,0,0,0,4,6,0,6,2,0,0,5,0,0,2,0,0,0,2},
+  {4,0,0,0,0,0,0,0,0,4,6,0,6,2,0,0,0,0,0,2,0,0,0,2},
+  {4,4,4,4,4,4,4,4,4,4,1,1,1,2,2,2,2,2,2,3,3,3,3,3}
+};
+
+Uint32 buffer[screenHeight][screenWidth];
+
+int main(int /*argc*/, char */*argv*/[])
+{
+  double posX = 22.0, posY = 11.5;  //x and y start position
+  double dirX = -1.0, dirY = 0.0; //initial direction vector
+  double planeX = 0.0, planeY = 0.66; //the 2d raycaster version of camera plane
+
+  double time = 0; //time of current frame
+  double oldTime = 0; //time of previous frame
+
+  std::vector<Uint32> texture[8];
+  for(int i = 0; i < 8; i++) texture[i].resize(texWidth * texHeight);
+
+  screen(screenWidth,screenHeight, 0, "Raycaster");
+
+  //generate some textures
+#if 0
+  for(int x = 0; x < texWidth; x++)
+  for(int y = 0; y < texHeight; y++)
+  {
+    int xorcolor = (x * 256 / texWidth) ^ (y * 256 / texHeight);
+    //int xcolor = x * 256 / texWidth;
+    int ycolor = y * 256 / texHeight;
+    int xycolor = y * 128 / texHeight + x * 128 / texWidth;
+    texture[0][texWidth * y + x] = 65536 * 254 * (x != y && x != texWidth - y); //flat red texture with black cross
+    texture[1][texWidth * y + x] = xycolor + 256 * xycolor + 65536 * xycolor; //sloped greyscale
+    texture[2][texWidth * y + x] = 256 * xycolor + 65536 * xycolor; //sloped yellow gradient
+    texture[3][texWidth * y + x] = xorcolor + 256 * xorcolor + 65536 * xorcolor; //xor greyscale
+    texture[4][texWidth * y + x] = 256 * xorcolor; //xor green
+    texture[5][texWidth * y + x] = 65536 * 192 * (x % 16 && y % 16); //red bricks
+    texture[6][texWidth * y + x] = 65536 * ycolor; //red gradient
+    texture[7][texWidth * y + x] = 128 + 256 * 128 + 65536 * 128; //flat grey texture
+  }
+#else
+ //generate some textures
+  unsigned long tw, th;
+  loadImage(texture[0], tw, th, "pics/eagle.png");
+  loadImage(texture[1], tw, th, "pics/redbrick.png");
+  loadImage(texture[2], tw, th, "pics/purplestone.png");
+  loadImage(texture[3], tw, th, "pics/greystone.png");
+  loadImage(texture[4], tw, th, "pics/bluestone.png");
+  loadImage(texture[5], tw, th, "pics/mossy.png");
+  loadImage(texture[6], tw, th, "pics/wood.png");
+  loadImage(texture[7], tw, th, "pics/colorstone.png");
+#endif
+
+  //start the main loop
+  while(!done())
+  {
+    for(int x = 0; x < w; x++)
+    {
+      //calculate ray position and direction
+      double cameraX = 2 * x / (double)w - 1; //x-coordinate in camera space
+      double rayDirX = dirX + planeX*cameraX;
+      double rayDirY = dirY + planeY*cameraX;
+
+      //which box of the map we're in
+      int mapX = int(posX);
+      int mapY = int(posY);
+
+      //length of ray from current position to next x or y-side
+      double sideDistX;
+      double sideDistY;
+
+      //length of ray from one x or y-side to next x or y-side
+      double deltaDistX = (rayDirX == 0) ? 1e30 : std::abs(1 / rayDirX);
+      double deltaDistY = (rayDirY == 0) ? 1e30 : std::abs(1 / rayDirY);
+      double perpWallDist;
+
+      //what direction to step in x or y-direction (either +1 or -1)
+      int stepX;
+      int stepY;
+
+      int hit = 0; //was there a wall hit?
+      int side; //was a NS or a EW wall hit?
+
+      //calculate step and initial sideDist
+      if(rayDirX < 0)
+      {
+        stepX = -1;
+        sideDistX = (posX - mapX) * deltaDistX;
+      }
+      else
+      {
+        stepX = 1;
+        sideDistX = (mapX + 1.0 - posX) * deltaDistX;
+      }
+      if(rayDirY < 0)
+      {
+        stepY = -1;
+        sideDistY = (posY - mapY) * deltaDistY;
+      }
+      else
+      {
+        stepY = 1;
+        sideDistY = (mapY + 1.0 - posY) * deltaDistY;
+      }
+      //perform DDA
+      while (hit == 0)
+      {
+        //jump to next map square, either in x-direction, or in y-direction
+        if(sideDistX < sideDistY)
+        {
+          sideDistX += deltaDistX;
+          mapX += stepX;
+          side = 0;
+        }
+        else
+        {
+          sideDistY += deltaDistY;
+          mapY += stepY;
+          side = 1;
+        }
+        //Check if ray has hit a wall
+        if(worldMap[mapX][mapY] > 0) hit = 1;
+      }
+
+      //Calculate distance of perpendicular ray (Euclidean distance would give fisheye effect!)
+      if(side == 0) perpWallDist = (sideDistX - deltaDistX);
+      else          perpWallDist = (sideDistY - deltaDistY);
+
+      //Calculate height of line to draw on screen
+      int lineHeight = (int)(h / perpWallDist);
+
+
+      int pitch = 100;
+
+      //calculate lowest and highest pixel to fill in current stripe
+      int drawStart = -lineHeight / 2 + h / 2 + pitch;
+      if(drawStart < 0) drawStart = 0;
+      int drawEnd = lineHeight / 2 + h / 2 + pitch;
+      if(drawEnd >= h) drawEnd = h - 1;
+
+      //texturing calculations
+      int texNum = worldMap[mapX][mapY] - 1; //1 subtracted from it so that texture 0 can be used!
+
+      //calculate value of wallX
+      double wallX; //where exactly the wall was hit
+      if(side == 0) wallX = posY + perpWallDist * rayDirY;
+      else          wallX = posX + perpWallDist * rayDirX;
+      wallX -= floor((wallX));
+
+      //x coordinate on the texture
+      int texX = int(wallX * double(texWidth));
+      if(side == 0 && rayDirX > 0) texX = texWidth - texX - 1;
+      if(side == 1 && rayDirY < 0) texX = texWidth - texX - 1;
+
+      // TODO: an integer-only bresenham or DDA like algorithm could make the texture coordinate stepping faster
+      // How much to increase the texture coordinate per screen pixel
+      double step = 1.0 * texHeight / lineHeight;
+      // Starting texture coordinate
+      double texPos = (drawStart - pitch - h / 2 + lineHeight / 2) * step;
+      for(int y = drawStart; y < drawEnd; y++)
+      {
+        // Cast the texture coordinate to integer, and mask with (texHeight - 1) in case of overflow
+        int texY = (int)texPos & (texHeight - 1);
+        texPos += step;
+        Uint32 color = texture[texNum][texHeight * texY + texX];
+        //make color darker for y-sides: R, G and B byte each divided through two with a "shift" and an "and"
+        if(side == 1) color = (color >> 1) & 8355711;
+        buffer[y][x] = color;
+      }
+    }
+
+    drawBuffer(buffer[0]);
+    for(int y = 0; y < h; y++) for(int x = 0; x < w; x++) buffer[y][x] = 0; //clear the buffer instead of cls()
+    //timing for input and FPS counter
+    oldTime = time;
+    time = getTicks();
+    double frameTime = (time - oldTime) / 1000.0; //frametime is the time this frame has taken, in seconds
+    print(1.0 / frameTime); //FPS counter
+    redraw();
+
+    //speed modifiers
+    double moveSpeed = frameTime * 5.0; //the constant value is in squares/second
+    double rotSpeed = frameTime * 3.0; //the constant value is in radians/second
+
+    readKeys();
+    //move forward if no wall in front of you
+    if(keyDown(SDLK_UP))
+    {
+      if(worldMap[int(posX + dirX * moveSpeed)][int(posY)] == false) posX += dirX * moveSpeed;
+      if(worldMap[int(posX)][int(posY + dirY * moveSpeed)] == false) posY += dirY * moveSpeed;
+    }
+    //move backwards if no wall behind you
+    if(keyDown(SDLK_DOWN))
+    {
+      if(worldMap[int(posX - dirX * moveSpeed)][int(posY)] == false) posX -= dirX * moveSpeed;
+      if(worldMap[int(posX)][int(posY - dirY * moveSpeed)] == false) posY -= dirY * moveSpeed;
+    }
+    //rotate to the right
+    if(keyDown(SDLK_RIGHT))
+    {
+      //both camera direction and camera plane must be rotated
+      double oldDirX = dirX;
+      dirX = dirX * cos(-rotSpeed) - dirY * sin(-rotSpeed);
+      dirY = oldDirX * sin(-rotSpeed) + dirY * cos(-rotSpeed);
+      double oldPlaneX = planeX;
+      planeX = planeX * cos(-rotSpeed) - planeY * sin(-rotSpeed);
+      planeY = oldPlaneX * sin(-rotSpeed) + planeY * cos(-rotSpeed);
+    }
+    //rotate to the left
+    if(keyDown(SDLK_LEFT))
+    {
+      //both camera direction and camera plane must be rotated
+      double oldDirX = dirX;
+      dirX = dirX * cos(rotSpeed) - dirY * sin(rotSpeed);
+      dirY = oldDirX * sin(rotSpeed) + dirY * cos(rotSpeed);
+      double oldPlaneX = planeX;
+      planeX = planeX * cos(rotSpeed) - planeY * sin(rotSpeed);
+      planeY = oldPlaneX * sin(rotSpeed) + planeY * cos(rotSpeed);
+    }
+    if(keyDown(SDLK_ESCAPE))
+    {
+      break;
+    }
+  }
+}

sample-macros.fnl

@@ -0,0 +1,13 @@
+(fn incf [value ?by]
+  `(set ,value (+ ,value (or ,?by 1))))
+
+(fn decf [value ?by]
+  `(set ,value (- ,value (or ,?by 1))))
+
+(fn with [t keys ?body]
+  `(let [,keys ,t]
+     (if ,?body
+         ,?body
+         ,keys)))
+
+{: incf : decf : with}

scripts/update-fennel.sh

@@ -0,0 +1,29 @@
+#!/bin/bash
+
+
+libdir=$1
+release=$2
+
+if [ "$#" = 0 ]; then
+    echo -e "Usage: update-fennel.sh libdir [release]\n\n\
+Example: ./update-fennel.sh \$(pwd)/../lib/ 1.2.0"
+    exit 0;
+fi
+
+cd /tmp/
+git clone https://github.com/bakpakin/Fennel.git
+cd Fennel
+
+
+if [ $release ]
+then
+    
+    git checkout tags/$release
+fi
+
+
+make
+
+cp fennel fennel.lua $libdir
+
+rm -rf /tmp/Fennel/

state.fnl

@@ -0,0 +1,35 @@
+; Handles game-play stateful information
+(local pi math.pi)
+
+; The Player table holds all the player stuff
+; The Inventory table holds the player's inventory
+; [x y] coordinates, [d]irection, [f]ield-of-view
+; [o]xygen and [p]ower
+(var player {:x 3.5 :y 3.5 :d 0 :f (/ pi 3)
+             :o 100 :p 45})
+(var inventory [])
+
+; The Map table holds the map
+(var map [])
+ 
+{:getPlayer (fn getPlayer [] player)
+ :getX (fn getX [] player.x)
+ :setX (fn setX [x] (set player.x x))
+ :getY (fn getY [] player.y)
+ :setY (fn setY [y] (set player.y y))
+ :getD (fn getD [] player.d)
+ :setD (fn setD [d] (set player.d d))
+ :getX (fn getX [] player.x)
+ :getO (fn getO [] player.o)
+ :setO (fn setO [x] (set player.o x))
+ :modO (fn modO [x] 
+         (if (< (+ player.o x) 0)
+           (set player.o 0)
+           (set player.o (+ player.o x))))
+ :getP (fn getP [] player.p)
+ :setP (fn setP [x] (set player.p x))
+ :modP (fn modP [x]
+         (if (< (+ player.p x) 0)
+           (set player.p 0)
+           (set player.p (+ player.p x))))
+}

wrap.fnl

@@ -0,0 +1,49 @@
+(local fennel (require :lib.fennel))
+(local repl (require :lib.stdio))
+(local canvas (let [(w h) (love.window.getMode)]
+                (love.graphics.newCanvas w h)))
+
+(var scale 1)
+
+;; set the first mode
+(var (mode mode-name) nil)
+
+(fn set-mode [new-mode-name ...]
+  (set (mode mode-name) (values (require new-mode-name) new-mode-name))
+  (when mode.activate
+    (match (pcall mode.activate ...)
+      (false msg) (print mode-name "activate error" msg))))
+
+(fn love.load [args]
+  ; THIS IS WHERE WE SET THE START MODE
+  ; ###################################
+  ; (set-mode :ray-cast-vectors)
+  (set-mode :mode-intro)
+  ; (set-mode :raycaster)
+  ; ###################################
+  (canvas:setFilter "nearest" "nearest")
+  (when (~= :web (. args 1)) (repl.start)))
+
+(fn safely [f]
+  (xpcall f #(set-mode :error-mode mode-name $ (fennel.traceback))))
+
+(fn love.draw []
+  ;; the canvas allows you to get sharp pixel-art style scaling; if you
+  ;; don't want that, just skip that and call mode.draw directly.
+  (love.graphics.setCanvas canvas)
+  (love.graphics.clear)
+  (love.graphics.setColor 1 1 1)
+  (safely mode.draw)
+  (love.graphics.setCanvas)
+  (love.graphics.setColor 1 1 1)
+  (love.graphics.draw canvas 0 0 0 scale scale))
+
+(fn love.update [dt]
+  (when mode.update
+    (safely #(mode.update dt set-mode))))
+
+(fn love.keypressed [key]
+  (if (and (love.keyboard.isDown "lctrl" "rctrl" "capslock") (= key "q"))
+      (love.event.quit)
+      ;; add what each keypress should do in each mode
+      (safely #(mode.keypressed key set-mode))))