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notes.md

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+First, establish some of the cell data
+
+```lisp
+; This will result in a "2x2" cell, of [0 1 1 1], with 0 representing an empty
+; space, and 1 representing a wall.
+(var (hall-width wall-width) (values 1 1))
+
+; This sets the "map width". This means 10 cells across and down. With each cell
+; being 2x2, this results in a 20x20 square map. All maps will be square (for
+; now).
+(var num-cells 10)
+
+; Explicitly setting cell-size for convenience. All cells are squares
+(var cell-size (+ hall-width wall-width))
+```
+
+Next, generate the initial array of cells to work with.
+
+```lisp
+(var cells {})
+(for [i 1 (* num-cells num-cells)]
+    (table.insert cells {
+        :n false :s false :e false :w false 
+        :v false 
+        :o false
+        }))
+```
+
+    `:n`, `:s`, `:e`, `:w` - if cell has a directional connection
+    `:v` - has the cell been visited
+    `:o` - does the cell contain an obstacle
+
+With the cells established, can use a recursive depth-first search with a stack
+to generate the maze.
+
+For ease, we'll always start along the top. Eventually, want to ensure the
+solution is along the sides or bottom.
+
+```lisp
+(var cell-stack [(math.random 1 num-cells)])
+
+(while (> 0 (length cell-stack)
+    (var current-cell (table.remove cell-stack (length cell-stack)))
+    (tset cells current-cell :v true)
+
+    ; Check if any of the current cell's neighbors are
+    ;   1. unvisited
+    ;   2. a side/barrier wall
+    (var next-cells {})
+
+    ; North - 
+    ;   if current-cell <= num-cells, then north is a map-side/barrier
+    (when (> num-cells current-cell)
+        (var n-cell (- current-cell num-cells))
+        (if (not (. cells n-cell :v)) (table.insert next-cells n-cell)))
+
+    ; South - 
+    ;   if current-cell > (- (* num-cells num-cells) num-cells), 
+    ;       then south is a map-side/barrier
+    (when (< current-cell (- (* num-cells num-cells) num-cells))
+        (var s-cell (- (* num-cells num-cells) num-cells))
+        (if (not (. cells s-cell :v)) (table.insert next-cells s-cell)))
+
+    ; East -
+    ;   if current-cell % num-cells = 0, then east is a map-side/barrier
+    (when (not (= 0 (% current-cell num-cells)))
+        (var e-cell (+ current-cell 1))
+        (if (not (. cells e-cell :v)) (table.insert next-cells e-cell)))
+
+    ; West -
+    ;   if current-cell % num-cells = 1, then west is a map-side/barrier
+    (when (not (= 1 (% current-cell num-cells)))
+        (var w-cell (- current-cell 1))
+        (if (not (. cells e-cell :v)) (table.insert next-cells w-cell)))
+
+```
+
+---
+For output:
+
+Each cell is then used to generate values in the map array. Each cell will have
+either a hallway or a wall at each position, for `cell-size` positions.
+
+Iterate through each cell. Cells 1 through `num-cells` are the first row, then
+(1 + `num-cells`) through (`num-cells` * 2), and so on. This can be generalized
+and extrapolated to `(x + (num-cells * (y - 1)))` through `(num-cells * y)`, for
+`x` and `y` loops from 1 to `num-cells`.
+
+```lisp
+(for [i 1 num-cells]
+    (for [j 1 num-cells]
+```
+
+Each cell is of uniform size, and the map is a square that divides evenly by
+that size. We established the width, and that value squared is the map. Every
+cell is numbered from 1 to `(* num-cells num-cells)` (ie., 1 to 100). The index
+of the cell divided by `num-cells`, plus 1, gets the row:
+
+```lisp
+(fn row [i] (+ 1 (// i num-cells)))
+```
+
+This gets the "upper-left" for the map array, given a cell index.
+
+```lisp
+(fn c [i] (+ (- (* i cell-size) 1) (* cell-size cell-num (- (row i) 1))))
+```
+
+Using that index, iterate through the cell based on `cell-size` twice, using
+each loop to add either `(- i 1)` and `(* (- j 1) cell-num)` to the value from
+`c` above, and insert it into the map array.
+
+---
+For cell generation:
+
+Each cell is a combination of hallways and walls. For each cell, if the "row" or
+"column" is less than the `hall-width`, enter a "0", otherwise enter a "1".
+
+```lisp
+(var cell [])
+(for [i 1 cell-size]
+    (for [j 1 cell-size]
+        (var cell-index (+ j (* (- i 1) cell-size)))
+        (if (and (< i (+ hall-width 1)) (< j (+ hall-width 1)))
+            (tset cell cell-index 0)
+            (tset cell cell-index 1))))
+```