Map generation limit: Make per-world

The setting limits map generation but affects nothing else.
Add 'mapgen_limit' to global mapgen parameters.
Move 'blockpos_over_mapgen_limit()' to the only place it is called
from: map.cpp.
Allow teleportation to any part of the world even if over the set
mapgen limit.
Simplify the reading of this limit in mgvalleys.
Remove the 'map_generation_limit' setting.

builtin/game/chatcommands.lua

@@ -303,7 +303,7 @@ core.register_chatcommand("teleport", {
 		p.y = tonumber(p.y)
 		p.z = tonumber(p.z)
 		if p.x and p.y and p.z then
-			local lm = tonumber(minetest.setting_get("map_generation_limit") or 31000)
+			local lm = 31000
 			if p.x < -lm or p.x > lm or p.y < -lm or p.y > lm or p.z < -lm or p.z > lm then
 				return false, "Cannot teleport out of map bounds!"
 			end

builtin/settingtypes.txt

@@ -893,13 +893,10 @@ water_level (Water level) int 1
 #    From how far blocks are generated for clients, stated in mapblocks (16 nodes).
 max_block_generate_distance (Max block generate distance) int 6
 
-#    Where the map generator stops.
-#    Please note:
-#    -    Limited to 31000 (setting above has no effect)
-#    -    The map generator works in groups of 80x80x80 nodes (5x5x5 MapBlocks).
-#    -    Those groups have an offset of -32, -32 nodes from the origin.
-#    -    Only groups which are within the map_generation_limit are generated
-map_generation_limit (Map generation limit) int 31000 0 31000
+#    Limit of map generation, in nodes, in all 6 directions from (0, 0, 0).
+#    Only mapchunks completely within the mapgen limit are generated.
+#    Value is stored per-world.
+mapgen_limit (Map generation limit) int 31000 0 31000
 
 #    Global map generation attributes.
 #    In Mapgen v6 the 'decorations' flag controls all decorations except trees

minetest.conf.example

@@ -1092,14 +1092,11 @@ server_side_occlusion_culling = true
 #    type: int
 # max_block_generate_distance = 6
 
-#    Where the map generator stops.
-#    Please note:
-#    -    Limited to 31000 (setting above has no effect)
-#    -    The map generator works in groups of 80x80x80 nodes (5x5x5 MapBlocks).
-#    -    Those groups have an offset of -32, -32 nodes from the origin.
-#    -    Only groups which are within the map_generation_limit are generated
+#    Limit of map generation, in nodes, in all 6 directions from (0, 0, 0).
+#    Only mapchunks completely within the mapgen limit are generated.
+#    Value is stored per-world.
 #    type: int min: 0 max: 31000
-# map_generation_limit = 31000
+# mapgen_limit = 31000
 
 #    Global map generation attributes.
 #    In Mapgen v6 the 'decorations' flag controls all decorations except trees

src/defaultsettings.cpp

@@ -333,10 +333,10 @@ void set_default_settings(Settings *settings)
 	// Mapgen
 	settings->setDefault("mg_name", "v7");
 	settings->setDefault("water_level", "1");
+	settings->setDefault("mapgen_limit", "31000");
 	settings->setDefault("chunksize", "5");
 	settings->setDefault("mg_flags", "dungeons");
 	settings->setDefault("fixed_map_seed", "");
-	settings->setDefault("map_generation_limit", "31000");
 	settings->setDefault("max_block_generate_distance", "7");
 	settings->setDefault("enable_mapgen_debug_info", "false");
 

src/map.cpp

@@ -1367,6 +1367,19 @@ s16 ServerMap::getWaterLevel()
 	return getMapgenParams()->water_level;
 }
 
+bool ServerMap::blockpos_over_mapgen_limit(v3s16 p)
+{
+	const s16 mapgen_limit_bp = rangelim(
+		getMapgenParams()->mapgen_limit, 0, MAX_MAP_GENERATION_LIMIT) /
+		MAP_BLOCKSIZE;
+	return p.X < -mapgen_limit_bp ||
+		p.X >  mapgen_limit_bp ||
+		p.Y < -mapgen_limit_bp ||
+		p.Y >  mapgen_limit_bp ||
+		p.Z < -mapgen_limit_bp ||
+		p.Z >  mapgen_limit_bp;
+}
+
 bool ServerMap::initBlockMake(v3s16 blockpos, BlockMakeData *data)
 {
 	s16 csize = getMapgenParams()->chunksize;

src/map.h

@@ -379,6 +379,7 @@ public:
 	/*
 		Blocks are generated by using these and makeBlock().
 	*/
+	bool blockpos_over_mapgen_limit(v3s16 p);
 	bool initBlockMake(v3s16 blockpos, BlockMakeData *data);
 	void finishBlockMake(BlockMakeData *data,
 		std::map<v3s16, MapBlock*> *changed_blocks);

src/mapblock.h

@@ -32,6 +32,7 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #include "modifiedstate.h"
 #include "util/numeric.h" // getContainerPos
 #include "settings.h"
+#include "mapgen.h"
 
 class Map;
 class NodeMetadataList;
@@ -689,19 +690,6 @@ inline bool blockpos_over_max_limit(v3s16 p)
 		p.Z >  max_limit_bp;
 }
 
-inline bool blockpos_over_mapgen_limit(v3s16 p)
-{
-	const s16 mapgen_limit_bp = rangelim(
-		g_settings->getS16("map_generation_limit"), 0, MAX_MAP_GENERATION_LIMIT) /
-		MAP_BLOCKSIZE;
-	return p.X < -mapgen_limit_bp ||
-		p.X >  mapgen_limit_bp ||
-		p.Y < -mapgen_limit_bp ||
-		p.Y >  mapgen_limit_bp ||
-		p.Z < -mapgen_limit_bp ||
-		p.Z >  mapgen_limit_bp;
-}
-
 /*
 	Returns the position of the block where the node is located
 */

src/mapgen.cpp

@@ -97,11 +97,12 @@ STATIC_ASSERT(
 
 Mapgen::Mapgen()
 {
-	generating  = false;
-	id          = -1;
-	seed        = 0;
-	water_level = 0;
-	flags       = 0;
+	generating   = false;
+	id           = -1;
+	seed         = 0;
+	water_level  = 0;
+	mapgen_limit = 0;
+	flags        = 0;
 
 	vm        = NULL;
 	ndef      = NULL;
@@ -114,11 +115,12 @@ Mapgen::Mapgen()
 Mapgen::Mapgen(int mapgenid, MapgenParams *params, EmergeManager *emerge) :
 	gennotify(emerge->gen_notify_on, &emerge->gen_notify_on_deco_ids)
 {
-	generating  = false;
-	id          = mapgenid;
-	water_level = params->water_level;
-	flags       = params->flags;
-	csize       = v3s16(1, 1, 1) * (params->chunksize * MAP_BLOCKSIZE);
+	generating   = false;
+	id           = mapgenid;
+	water_level  = params->water_level;
+	mapgen_limit = params->mapgen_limit;
+	flags        = params->flags;
+	csize        = v3s16(1, 1, 1) * (params->chunksize * MAP_BLOCKSIZE);
 
 	/*
 		We are losing half our entropy by doing this, but it is necessary to
@@ -1005,6 +1007,7 @@ void MapgenParams::readParams(const Settings *settings)
 		this->mgtype = Mapgen::getMapgenType(mg_name);
 
 	settings->getS16NoEx("water_level", water_level);
+	settings->getS16NoEx("mapgen_limit", mapgen_limit);
 	settings->getS16NoEx("chunksize", chunksize);
 	settings->getFlagStrNoEx("mg_flags", flags, flagdesc_mapgen);
 
@@ -1022,6 +1025,7 @@ void MapgenParams::writeParams(Settings *settings) const
 	settings->set("mg_name", Mapgen::getMapgenName(mgtype));
 	settings->setU64("seed", seed);
 	settings->setS16("water_level", water_level);
+	settings->setS16("mapgen_limit", mapgen_limit);
 	settings->setS16("chunksize", chunksize);
 	settings->setFlagStr("mg_flags", flags, flagdesc_mapgen, U32_MAX);
 

src/mapgen.h

@@ -124,6 +124,7 @@ struct MapgenParams {
 	s16 chunksize;
 	u64 seed;
 	s16 water_level;
+	s16 mapgen_limit;
 	u32 flags;
 
 	BiomeParams *bparams;
@@ -133,6 +134,7 @@ struct MapgenParams {
 		chunksize(5),
 		seed(0),
 		water_level(1),
+		mapgen_limit(MAX_MAP_GENERATION_LIMIT),
 		flags(MG_CAVES | MG_LIGHT | MG_DECORATIONS),
 		bparams(NULL)
 	{
@@ -158,6 +160,7 @@ class Mapgen {
 public:
 	s32 seed;
 	int water_level;
+	int mapgen_limit;
 	u32 flags;
 	bool generating;
 	int id;

src/mapgen_valleys.cpp

@@ -70,9 +70,6 @@ MapgenValleys::MapgenValleys(int mapgenid, MapgenValleysParams *params, EmergeMa
 	// NOTE: MapgenValleys has a hard dependency on BiomeGenOriginal
 	this->m_bgen = (BiomeGenOriginal *)biomegen;
 
-	this->map_gen_limit = MYMIN(MAX_MAP_GENERATION_LIMIT,
-			g_settings->getU16("map_generation_limit"));
-
 	BiomeParamsOriginal *bp = (BiomeParamsOriginal *)params->bparams;
 
 	this->spflags            = params->spflags;
@@ -621,7 +618,7 @@ void MapgenValleys::generateCaves(s16 max_stone_y, s16 large_cave_depth)
 	const float massive_cave_threshold = 0.6f;
 	// mct: 1 = small rare caves, 0.5 1/3rd ground volume, 0 = 1/2 ground volume.
 
-	float yblmin = -map_gen_limit + massive_cave_blend * 1.5f;
+	float yblmin = -mapgen_limit + massive_cave_blend * 1.5f;
 	float yblmax = massive_cave_depth - massive_cave_blend * 1.5f;
 	bool made_a_big_one = false;
 
@@ -646,11 +643,11 @@ void MapgenValleys::generateCaves(s16 max_stone_y, s16 large_cave_depth)
 
 	// lava_depth varies between one and ten as you approach
 	//  the bottom of the world.
-	s16 lava_depth = ceil((lava_max_height - node_min.Y + 1) * 10.f / map_gen_limit);
+	s16 lava_depth = ceil((lava_max_height - node_min.Y + 1) * 10.f / mapgen_limit);
 	// This allows random lava spawns to be less common at the surface.
 	s16 lava_chance = MYCUBE(lava_features_lim) * lava_depth;
 	// water_depth varies between ten and one on the way down.
-	s16 water_depth = ceil((map_gen_limit - abs(node_min.Y) + 1) * 10.f / map_gen_limit);
+	s16 water_depth = ceil((mapgen_limit - abs(node_min.Y) + 1) * 10.f / mapgen_limit);
 	// This allows random water spawns to be more common at the surface.
 	s16 water_chance = MYCUBE(water_features_lim) * water_depth;
 

src/mapgen_valleys.h

@@ -101,8 +101,6 @@ public:
 private:
 	BiomeGenOriginal *m_bgen;
 
-	float map_gen_limit;
-
 	bool humid_rivers;
 	bool use_altitude_chill;
 	float humidity_adjust;