Allow chunksize to be non-cubic

doc/lua_api.md

@@ -6704,7 +6704,7 @@ Environment access
       in that order.
     * `mapgen_limit` is an optional number. If it is absent, its value is that
       of the *active* mapgen setting `"mapgen_limit"`.
-    * `chunksize` is an optional number. If it is absent, its value is that
+    * `chunksize` is an optional number or vector. If it is absent, its value is that
       of the *active* mapgen setting `"chunksize"`.
 * `core.get_mapgen_chunksize()`
     * Returns the currently active chunksize of the mapgen, as a vector.

doc/world_format.md

@@ -249,7 +249,7 @@ Example content:
 
 # Map File Format
 
-Luanti maps consist of `MapBlock`s, chunks of 16x16x16 nodes.
+Luanti maps consist of `MapBlock`s, each holds 16x16x16 nodes.
 
 In addition to the bulk node data, `MapBlock`s stored on disk also contain
 other things.

src/mapgen/mapgen.cpp

@@ -1073,9 +1073,27 @@ void MapgenParams::readParams(const Settings *settings)
 	settings->getS16NoEx("mapgen_limit", mapgen_limit);
 	settings->getFlagStrNoEx("mg_flags", flags, flagdesc_mapgen);
 
-	s16 tmp;
+	std::string chunksize_str;
-	settings->getS16NoEx("chunksize", tmp);
+	settings->getNoEx("chunksize", chunksize_str);
-	chunksize = v3s16(rangelim(tmp, 1, 24));
+	if (is_number(chunksize_str)) {
+		chunksize = v3s16(stoi(chunksize_str, 1, 999));
+	} else if (auto tmp = str_to_v3f(chunksize_str); tmp.has_value()) {
+		chunksize = v3s16(
+			rangelim(tmp->X, 1, 999),
+			rangelim(tmp->Y, 1, 999),
+			rangelim(tmp->Z, 1, 999)
+		);
+	} else if (!chunksize_str.empty()) {
+		errorstream << "MapgenParams: invalid chunksize \"" << chunksize_str
+			<< "\"" << std::endl;
+	}
+	// Finally check the volume limit
+	if (u32 v = chunksize.X * chunksize.Y * chunksize.Z; v > MAX_CHUNK_VOLUME) {
+		errorstream << "MapgenParams: chunksize " << chunksize
+			<< " is too big (volume > " << MAX_CHUNK_VOLUME
+			<< "), falling back to the default." << std::endl;
+		chunksize = v3s16(5);
+	}
 
 	delete bparams;
 	bparams = BiomeManager::createBiomeParams(BIOMEGEN_ORIGINAL);
@@ -1092,9 +1110,15 @@ void MapgenParams::writeParams(Settings *settings) const
 	settings->setU64("seed", seed);
 	settings->setS16("water_level", water_level);
 	settings->setS16("mapgen_limit", mapgen_limit);
-	settings->setS16("chunksize", chunksize.X); // TODO
 	settings->setFlagStr("mg_flags", flags, flagdesc_mapgen);
 
+	// Write as number if cubic, for backwards-compatibility
+	if (chunksize.X == chunksize.Y && chunksize.Y == chunksize.Z) {
+		settings->setS16("chunksize", chunksize.X);
+	} else {
+		settings->setV3F("chunksize", v3f::from(chunksize));
+	}
+
 	if (bparams)
 		bparams->writeParams(settings);
 }

src/mapgen/mapgen.h

@@ -127,6 +127,9 @@ struct MapgenParams {
 	virtual void setDefaultSettings(Settings *settings) {};
 
 	s32 getSpawnRangeMax();
+
+	// Mostly arbitrary limit
+	constexpr static u32 MAX_CHUNK_VOLUME = 2000;
 };
 
 

src/script/lua_api/l_mapgen.cpp

@@ -861,6 +861,8 @@ int ModApiMapgen::l_get_mapgen_edges(lua_State *L)
 	v3s16 chunksize;
 	if (lua_isnumber(L, 2)) {
 		chunksize = v3s16(lua_tointeger(L, 2));
+	} else if (lua_istable(L, 2)) {
+		chunksize = check_v3s16(L, 2);
 	} else {
 		chunksize = params->chunksize;
 	}