Mapgen: Add flat mapgen in hidden form
authorparamat <mat.gregory@virginmedia.com>
Fri, 30 Oct 2015 02:45:38 +0000 (02:45 +0000)
committerparamat <mat.gregory@virginmedia.com>
Wed, 11 Nov 2015 09:37:54 +0000 (09:37 +0000)
build/android/jni/Android.mk
builtin/settingtypes.txt
minetest.conf.example
src/CMakeLists.txt
src/emerge.cpp
src/mapgen_flat.cpp [new file with mode: 0644]
src/mapgen_flat.h [new file with mode: 0644]

index 324e1666b2581cf076a3f56436021c1cd87febce..b8fd9db78e3b71c92f64068b4752fbe1e0fbfff3 100644 (file)
@@ -173,6 +173,7 @@ LOCAL_SRC_FILES :=                                \
                jni/src/mapblock.cpp                      \
                jni/src/mapblock_mesh.cpp                 \
                jni/src/mapgen.cpp                        \
+               jni/src/mapgen_flat.cpp                   \
                jni/src/mapgen_fractal.cpp                \
                jni/src/mapgen_singlenode.cpp             \
                jni/src/mapgen_v5.cpp                     \
index 3c44ea664ffd79a8aa38910e89cebf5b8e80034d..8ac6ab6da895e89705d626094ec8e99c1ead838b 100644 (file)
@@ -812,7 +812,7 @@ liquid_update (Liquid update tick) float 1.0
 
 #    Name of map generator to be used when creating a new world.
 #    Creating a world in the main menu will override this.
-mg_name (Mapgen name) enum v6 v5,v6,v7,fractal,singlenode
+mg_name (Mapgen name) enum v6 v5,v6,v7,flat,fractal,singlenode
 
 #    Water surface level of the world.
 water_level (Water level) int 1
@@ -928,6 +928,45 @@ mgv7_np_ridge (Mapgen v7 ridge noise parameters) noise_params 0, 1, (100, 100, 1
 mgv7_np_cave1 (Mapgen v7 cave1 noise parameters) noise_params 0, 12, (100, 100, 100), 52534, 4, 0.5, 2.0
 mgv7_np_cave2 (Mapgen v7 cave2 noise parameters) noise_params 0, 12, (100, 100, 100), 10325, 4, 0.5, 2.0
 
+[***Mapgen flat]
+
+#    Map generation attributes specific to Mapgen flat.
+#    Occasional lakes and hills added to the flat world.
+#    Flags that are not specified in the flag string are not modified from the default.
+#    Flags starting with "no" are used to explicitly disable them.
+mgflat_spflags (Mapgen flat flags) flags nolakes,nohills lakes,hills,nolakes,nohills
+
+#    Y of flat ground.
+mgflat_ground_level (Mapgen flat ground level) int 8
+
+#    Y of upper limit of large pseudorandom caves.
+mgflat_large_cave_depth (Mapgen flat large cave depth) int -33
+
+#    Terrain noise threshold for lakes.
+#    Controls proportion of world area covered by lakes.
+#    Adjust towards 0.0 for a larger proportion.
+mgflat_lake_threshold (Mapgen flat lake threshold) float -0.45
+
+#    Controls steepness/depth of lake depressions.
+mgflat_lake_steepness (Mapgen flat lake steepness) float 48.0
+
+#    Terrain noise threshold for hills.
+#    Controls proportion of world area covered by hills.
+#    Adjust towards 0.0 for a larger proportion.
+mgflat_hill_threshold (Mapgen flat hill threshold) float 0.45
+
+#    Controls steepness/height of hills.
+mgflat_hill_steepness (Mapgen flat hill steepness) float 64.0
+
+#    Determines terrain shape.
+#    The 3 numbers in brackets control the scale of the
+#    terrain, the 3 numbers should be identical.
+mgflat_np_terrain (Mapgen flat terrain noise parameters) noise_params 0, 1, (600, 600, 600), 7244, 5, 0.6, 2.0
+
+mgflat_np_filler_depth (Mapgen flat filler depth noise parameters) noise_params 0, 1.2, (150, 150, 150), 261, 3, 0.7, 2.0
+mgflat_np_cave1 (Mapgen flat cave1 noise parameters) noise_params 0, 12, (128, 128, 128), 52534, 4, 0.5, 2.0
+mgflat_np_cave2 (Mapgen flat cave2 noise parameters) noise_params 0, 12, (128, 128, 128), 10325, 4, 0.5, 2.0
+
 [***Mapgen fractal]
 
 #    Map generation attributes specific to Mapgen fractal.
index f590aefaf1404fd0a8481a40ff3ba93671a63537..10b090bebeefbb3dcd127d4e49072080b6c60fca 100644 (file)
 
 #    Name of map generator to be used when creating a new world.
 #    Creating a world in the main menu will override this.
-#    type: enum values: v5, v6, v7, fractal, singlenode
+#    type: enum values: v5, v6, v7, flat, fractal, singlenode
 # mg_name = v6
 
 #    Water surface level of the world.
 #    type: noise_params
 # mgv7_np_cave2 = 0, 12, (100, 100, 100), 10325, 4, 0.5, 2.0
 
+#### Mapgen flat
+
+#    Map generation attributes specific to Mapgen flat.
+#    Occasional lakes and hills added to the flat world.
+#    Flags that are not specified in the flag string are not modified from the default.
+#    Flags starting with "no" are used to explicitly disable them.
+#    type: flags possible values: lakes, hills, nolakes, nohills
+# mgflat_spflags = nolakes,nohills
+
+#    Y of flat ground.
+#    type: int
+# mgflat_ground_level = 8
+
+#    Y of upper limit of large pseudorandom caves.
+#    type: int
+# mgflat_large_cave_depth = -33
+
+#    Terrain noise threshold for lakes.
+#    Controls proportion of world area covered by lakes.
+#    Adjust towards 0.0 for a larger proportion.
+#    type: float
+# mgflat_lake_threshold = -0.45
+
+#    Controls steepness/depth of lake depressions.
+#    type: float
+# mgflat_lake_steepness = 48.0
+
+#    Terrain noise threshold for hills.
+#    Controls proportion of world area covered by hills.
+#    Adjust towards 0.0 for a larger proportion.
+#    type: float
+# mgflat_hill_threshold = 0.45
+
+#    Controls steepness/height of hills.
+#    type: float
+# mgflat_hill_steepness = 64.0
+
+#    Determines terrain shape.
+#    The 3 numbers in brackets control the scale of the
+#    terrain, the 3 numbers should be identical.
+#    type: noise_params
+# mgflat_np_terrain = 0, 1, (600, 600, 600), 7244, 5, 0.6, 2.0
+
+#    type: noise_params
+# mgflat_np_filler_depth = 0, 1.2, (150, 150, 150), 261, 3, 0.7, 2.0
+
+#    type: noise_params
+# mgflat_np_cave1 = 0, 12, (128, 128, 128), 52534, 4, 0.5, 2.0
+
+#    type: noise_params
+# mgflat_np_cave2 = 0, 12, (128, 128, 128), 10325, 4, 0.5, 2.0
+
 #### Mapgen fractal
 
 #    Map generation attributes specific to Mapgen fractal.
index 55f5d4ad850777a2b1e122a7e04a2132171eed0a..dfbd2f5d8c84ab717651969bbd6c7300e778159e 100644 (file)
@@ -367,6 +367,7 @@ set(common_SRCS
        map.cpp
        mapblock.cpp
        mapgen.cpp
+       mapgen_flat.cpp
        mapgen_fractal.cpp
        mapgen_singlenode.cpp
        mapgen_v5.cpp
index 392a9d81e7cd6835095ef8b4d68086d3b2db1efc..a60f67ac52166d3bc5e35b929a02c3f48594a431 100644 (file)
@@ -34,6 +34,7 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #include "log.h"
 #include "map.h"
 #include "mapblock.h"
+#include "mapgen_flat.h"
 #include "mapgen_fractal.h"
 #include "mapgen_v5.h"
 #include "mapgen_v6.h"
@@ -105,6 +106,7 @@ MapgenDesc g_reg_mapgens[] = {
        {"v5",         new MapgenFactoryV5,         true},
        {"v6",         new MapgenFactoryV6,         true},
        {"v7",         new MapgenFactoryV7,         true},
+       {"flat",       new MapgenFactoryFlat,       false},
        {"fractal",    new MapgenFactoryFractal,    false},
        {"singlenode", new MapgenFactorySinglenode, false},
 };
diff --git a/src/mapgen_flat.cpp b/src/mapgen_flat.cpp
new file mode 100644 (file)
index 0000000..7a8fe18
--- /dev/null
@@ -0,0 +1,581 @@
+/*
+Minetest
+Copyright (C) 2010-2015 kwolekr, Ryan Kwolek <kwolekr@minetest.net>
+Copyright (C) 2010-2015 paramat, Matt Gregory
+
+This program is free software; you can redistribute it and/or modify
+it under the terms of the GNU Lesser General Public License as published by
+the Free Software Foundation; either version 2.1 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 Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public License along
+with this program; if not, write to the Free Software Foundation, Inc.,
+51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+*/
+
+
+#include "mapgen.h"
+#include "voxel.h"
+#include "noise.h"
+#include "mapblock.h"
+#include "mapnode.h"
+#include "map.h"
+#include "content_sao.h"
+#include "nodedef.h"
+#include "voxelalgorithms.h"
+//#include "profiler.h" // For TimeTaker
+#include "settings.h" // For g_settings
+#include "emerge.h"
+#include "dungeongen.h"
+#include "cavegen.h"
+#include "treegen.h"
+#include "mg_biome.h"
+#include "mg_ore.h"
+#include "mg_decoration.h"
+#include "mapgen_flat.h"
+
+
+FlagDesc flagdesc_mapgen_flat[] = {
+       {"lakes", MGFLAT_LAKES},
+       {"hills", MGFLAT_HILLS},
+       {NULL,    0}
+};
+
+///////////////////////////////////////////////////////////////////////////////////////
+
+
+MapgenFlat::MapgenFlat(int mapgenid, MapgenParams *params, EmergeManager *emerge)
+       : Mapgen(mapgenid, params, emerge)
+{
+       this->m_emerge = emerge;
+       this->bmgr     = emerge->biomemgr;
+
+       //// amount of elements to skip for the next index
+       //// for noise/height/biome maps (not vmanip)
+       this->ystride = csize.X;
+       this->zstride = csize.X * (csize.Y + 2);
+
+       this->biomemap        = new u8[csize.X * csize.Z];
+       this->heightmap       = new s16[csize.X * csize.Z];
+       this->heatmap         = NULL;
+       this->humidmap        = NULL;
+
+       MapgenFlatParams *sp = (MapgenFlatParams *)params->sparams;
+       this->spflags = sp->spflags;
+
+       this->ground_level = sp->ground_level;
+       this->large_cave_depth = sp->large_cave_depth;
+       this->lake_threshold = sp->lake_threshold;
+       this->lake_steepness = sp->lake_steepness;
+       this->hill_threshold = sp->hill_threshold;
+       this->hill_steepness = sp->hill_steepness;
+
+       //// 2D noise
+       noise_terrain      = new Noise(&sp->np_terrain,      seed, csize.X, csize.Z);
+       noise_filler_depth = new Noise(&sp->np_filler_depth, seed, csize.X, csize.Z);
+
+       //// 3D noise
+       noise_cave1 = new Noise(&sp->np_cave1, seed, csize.X, csize.Y + 2, csize.Z);
+       noise_cave2 = new Noise(&sp->np_cave2, seed, csize.X, csize.Y + 2, csize.Z);
+
+       //// Biome noise
+       noise_heat           = new Noise(&params->np_biome_heat,           seed, csize.X, csize.Z);
+       noise_humidity       = new Noise(&params->np_biome_humidity,       seed, csize.X, csize.Z);
+       noise_heat_blend     = new Noise(&params->np_biome_heat_blend,     seed, csize.X, csize.Z);
+       noise_humidity_blend = new Noise(&params->np_biome_humidity_blend, seed, csize.X, csize.Z);
+
+       //// Resolve nodes to be used
+       INodeDefManager *ndef = emerge->ndef;
+
+       c_stone                = ndef->getId("mapgen_stone");
+       c_water_source         = ndef->getId("mapgen_water_source");
+       c_lava_source          = ndef->getId("mapgen_lava_source");
+       c_desert_stone         = ndef->getId("mapgen_desert_stone");
+       c_ice                  = ndef->getId("mapgen_ice");
+       c_sandstone            = ndef->getId("mapgen_sandstone");
+
+       c_cobble               = ndef->getId("mapgen_cobble");
+       c_stair_cobble         = ndef->getId("mapgen_stair_cobble");
+       c_mossycobble          = ndef->getId("mapgen_mossycobble");
+       c_sandstonebrick       = ndef->getId("mapgen_sandstonebrick");
+       c_stair_sandstonebrick = ndef->getId("mapgen_stair_sandstonebrick");
+
+       if (c_ice == CONTENT_IGNORE)
+               c_ice = CONTENT_AIR;
+       if (c_mossycobble == CONTENT_IGNORE)
+               c_mossycobble = c_cobble;
+       if (c_stair_cobble == CONTENT_IGNORE)
+               c_stair_cobble = c_cobble;
+       if (c_sandstonebrick == CONTENT_IGNORE)
+               c_sandstonebrick = c_sandstone;
+       if (c_stair_sandstonebrick == CONTENT_IGNORE)
+               c_stair_sandstonebrick = c_sandstone;
+}
+
+
+MapgenFlat::~MapgenFlat()
+{
+       delete noise_terrain;
+       delete noise_filler_depth;
+       delete noise_cave1;
+       delete noise_cave2;
+
+       delete noise_heat;
+       delete noise_humidity;
+       delete noise_heat_blend;
+       delete noise_humidity_blend;
+
+       delete[] heightmap;
+       delete[] biomemap;
+}
+
+
+MapgenFlatParams::MapgenFlatParams()
+{
+       spflags = 0;
+
+       ground_level = 8;
+       large_cave_depth = -33;
+       lake_threshold = -0.45;
+       lake_steepness = 48.0;
+       hill_threshold = 0.45;
+       hill_steepness = 64.0;
+
+       np_terrain      = NoiseParams(0, 1,   v3f(600, 600, 600), 7244,  5, 0.6, 2.0);
+       np_filler_depth = NoiseParams(0, 1.2, v3f(150, 150, 150), 261,   3, 0.7, 2.0);
+       np_cave1        = NoiseParams(0, 12,  v3f(128, 128, 128), 52534, 4, 0.5, 2.0);
+       np_cave2        = NoiseParams(0, 12,  v3f(128, 128, 128), 10325, 4, 0.5, 2.0);
+}
+
+
+void MapgenFlatParams::readParams(const Settings *settings)
+{
+       settings->getFlagStrNoEx("mgflat_spflags", spflags, flagdesc_mapgen_flat);
+
+       settings->getS16NoEx("mgflat_ground_level",     ground_level);
+       settings->getS16NoEx("mgflat_large_cave_depth", large_cave_depth);
+       settings->getFloatNoEx("mgflat_lake_threshold", lake_threshold);
+       settings->getFloatNoEx("mgflat_lake_steepness", lake_steepness);
+       settings->getFloatNoEx("mgflat_hill_threshold", hill_threshold);
+       settings->getFloatNoEx("mgflat_hill_steepness", hill_steepness);
+
+       settings->getNoiseParams("mgflat_np_terrain",      np_terrain);
+       settings->getNoiseParams("mgflat_np_filler_depth", np_filler_depth);
+       settings->getNoiseParams("mgflat_np_cave1",        np_cave1);
+       settings->getNoiseParams("mgflat_np_cave2",        np_cave2);
+}
+
+
+void MapgenFlatParams::writeParams(Settings *settings) const
+{
+       settings->setFlagStr("mgflat_spflags", spflags, flagdesc_mapgen_flat, U32_MAX);
+
+       settings->setS16("mgflat_ground_level",     ground_level);
+       settings->setS16("mgflat_large_cave_depth", large_cave_depth);
+       settings->setFloat("mgflat_lake_threshold", lake_threshold);
+       settings->setFloat("mgflat_lake_steepness", lake_steepness);
+       settings->setFloat("mgflat_hill_threshold", hill_threshold);
+       settings->setFloat("mgflat_hill_steepness", hill_steepness);
+
+       settings->setNoiseParams("mgflat_np_terrain",      np_terrain);
+       settings->setNoiseParams("mgflat_np_filler_depth", np_filler_depth);
+       settings->setNoiseParams("mgflat_np_cave1",        np_cave1);
+       settings->setNoiseParams("mgflat_np_cave2",        np_cave2);
+}
+
+
+/////////////////////////////////////////////////////////////////
+
+
+int MapgenFlat::getGroundLevelAtPoint(v2s16 p)
+{
+       float n_terrain = NoisePerlin2D(&noise_terrain->np, p.X, p.Y, seed);
+       if ((spflags & MGFLAT_LAKES) && n_terrain < lake_threshold) {
+               s16 depress = (lake_threshold - n_terrain) * lake_steepness;
+               return ground_level - depress;
+       } else if ((spflags & MGFLAT_HILLS) && n_terrain > hill_threshold) {
+               s16 rise = (n_terrain - hill_threshold) * hill_steepness;
+               return ground_level + rise;
+       } else {
+               return ground_level;
+       }
+}
+
+
+void MapgenFlat::makeChunk(BlockMakeData *data)
+{
+       // Pre-conditions
+       assert(data->vmanip);
+       assert(data->nodedef);
+       assert(data->blockpos_requested.X >= data->blockpos_min.X &&
+               data->blockpos_requested.Y >= data->blockpos_min.Y &&
+               data->blockpos_requested.Z >= data->blockpos_min.Z);
+       assert(data->blockpos_requested.X <= data->blockpos_max.X &&
+               data->blockpos_requested.Y <= data->blockpos_max.Y &&
+               data->blockpos_requested.Z <= data->blockpos_max.Z);
+
+       this->generating = true;
+       this->vm   = data->vmanip;
+       this->ndef = data->nodedef;
+       //TimeTaker t("makeChunk");
+
+       v3s16 blockpos_min = data->blockpos_min;
+       v3s16 blockpos_max = data->blockpos_max;
+       node_min = blockpos_min * MAP_BLOCKSIZE;
+       node_max = (blockpos_max + v3s16(1, 1, 1)) * MAP_BLOCKSIZE - v3s16(1, 1, 1);
+       full_node_min = (blockpos_min - 1) * MAP_BLOCKSIZE;
+       full_node_max = (blockpos_max + 2) * MAP_BLOCKSIZE - v3s16(1, 1, 1);
+
+       blockseed = getBlockSeed2(full_node_min, seed);
+
+       // Make some noise
+       calculateNoise();
+
+       // Generate base terrain, mountains, and ridges with initial heightmaps
+       s16 stone_surface_max_y = generateTerrain();
+
+       // Create heightmap
+       updateHeightmap(node_min, node_max);
+
+       // Create biomemap at heightmap surface
+       bmgr->calcBiomes(csize.X, csize.Z, noise_heat->result,
+               noise_humidity->result, heightmap, biomemap);
+
+       // Actually place the biome-specific nodes
+       MgStoneType stone_type = generateBiomes(noise_heat->result, noise_humidity->result);
+
+       if (flags & MG_CAVES)
+               generateCaves(stone_surface_max_y);
+
+       if ((flags & MG_DUNGEONS) && (stone_surface_max_y >= node_min.Y)) {
+               DungeonParams dp;
+
+               dp.np_rarity  = nparams_dungeon_rarity;
+               dp.np_density = nparams_dungeon_density;
+               dp.np_wetness = nparams_dungeon_wetness;
+               dp.c_water    = c_water_source;
+               if (stone_type == STONE) {
+                       dp.c_cobble = c_cobble;
+                       dp.c_moss   = c_mossycobble;
+                       dp.c_stair  = c_stair_cobble;
+
+                       dp.diagonal_dirs = false;
+                       dp.mossratio     = 3.0;
+                       dp.holesize      = v3s16(1, 2, 1);
+                       dp.roomsize      = v3s16(0, 0, 0);
+                       dp.notifytype    = GENNOTIFY_DUNGEON;
+               } else if (stone_type == DESERT_STONE) {
+                       dp.c_cobble = c_desert_stone;
+                       dp.c_moss   = c_desert_stone;
+                       dp.c_stair  = c_desert_stone;
+
+                       dp.diagonal_dirs = true;
+                       dp.mossratio     = 0.0;
+                       dp.holesize      = v3s16(2, 3, 2);
+                       dp.roomsize      = v3s16(2, 5, 2);
+                       dp.notifytype    = GENNOTIFY_TEMPLE;
+               } else if (stone_type == SANDSTONE) {
+                       dp.c_cobble = c_sandstonebrick;
+                       dp.c_moss   = c_sandstonebrick;
+                       dp.c_stair  = c_sandstonebrick;
+
+                       dp.diagonal_dirs = false;
+                       dp.mossratio     = 0.0;
+                       dp.holesize      = v3s16(2, 2, 2);
+                       dp.roomsize      = v3s16(2, 0, 2);
+                       dp.notifytype    = GENNOTIFY_DUNGEON;
+               }
+
+               DungeonGen dgen(this, &dp);
+               dgen.generate(blockseed, full_node_min, full_node_max);
+       }
+
+       // Generate the registered decorations
+       m_emerge->decomgr->placeAllDecos(this, blockseed, node_min, node_max);
+
+       // Generate the registered ores
+       m_emerge->oremgr->placeAllOres(this, blockseed, node_min, node_max);
+
+       // Sprinkle some dust on top after everything else was generated
+       dustTopNodes();
+
+       //printf("makeChunk: %dms\n", t.stop());
+
+       updateLiquid(&data->transforming_liquid, full_node_min, full_node_max);
+
+       if (flags & MG_LIGHT)
+               calcLighting(node_min - v3s16(0, 1, 0), node_max + v3s16(0, 1, 0),
+                       full_node_min, full_node_max);
+
+       //setLighting(node_min - v3s16(1, 0, 1) * MAP_BLOCKSIZE,
+       //                      node_max + v3s16(1, 0, 1) * MAP_BLOCKSIZE, 0xFF);
+
+       this->generating = false;
+}
+
+
+void MapgenFlat::calculateNoise()
+{
+       //TimeTaker t("calculateNoise", NULL, PRECISION_MICRO);
+       int x = node_min.X;
+       int y = node_min.Y - 1;
+       int z = node_min.Z;
+
+       if ((spflags & MGFLAT_LAKES) || (spflags & MGFLAT_HILLS))
+               noise_terrain->perlinMap2D(x, z);
+
+       noise_filler_depth->perlinMap2D(x, z);
+
+       if (flags & MG_CAVES) {
+               noise_cave1->perlinMap3D(x, y, z);
+               noise_cave2->perlinMap3D(x, y, z);
+       }
+
+       noise_heat->perlinMap2D(x, z);
+       noise_humidity->perlinMap2D(x, z);
+       noise_heat_blend->perlinMap2D(x, z);
+       noise_humidity_blend->perlinMap2D(x, z);
+
+       for (s32 i = 0; i < csize.X * csize.Z; i++) {
+               noise_heat->result[i] += noise_heat_blend->result[i];
+               noise_humidity->result[i] += noise_humidity_blend->result[i];
+       }
+
+       heatmap = noise_heat->result;
+       humidmap = noise_humidity->result;
+       //printf("calculateNoise: %dus\n", t.stop());
+}
+
+
+s16 MapgenFlat::generateTerrain()
+{
+       MapNode n_air(CONTENT_AIR);
+       MapNode n_stone(c_stone);
+       MapNode n_water(c_water_source);
+
+       v3s16 em = vm->m_area.getExtent();
+       s16 stone_surface_max_y = -MAX_MAP_GENERATION_LIMIT;
+       u32 ni2d = 0;
+
+       for (s16 z = node_min.Z; z <= node_max.Z; z++)
+       for (s16 x = node_min.X; x <= node_max.X; x++, ni2d++) {
+               s16 stone_level = ground_level;
+               float n_terrain = 0.0f;
+
+               if ((spflags & MGFLAT_LAKES) || (spflags & MGFLAT_HILLS))
+                       n_terrain = noise_terrain->result[ni2d];
+
+               if ((spflags & MGFLAT_LAKES) && n_terrain < lake_threshold) {
+                       s16 depress = (lake_threshold - n_terrain) * lake_steepness;
+                       stone_level = ground_level - depress;
+               } else if ((spflags & MGFLAT_HILLS) && n_terrain > hill_threshold) {
+                       s16 rise = (n_terrain - hill_threshold) * hill_steepness;
+                       stone_level = ground_level + rise;
+               }
+
+               u32 vi = vm->m_area.index(x, node_min.Y - 1, z);
+               for (s16 y = node_min.Y - 1; y <= node_max.Y + 1; y++) {
+                       if (vm->m_data[vi].getContent() == CONTENT_IGNORE) {
+                               if (y <= stone_level) {
+                                       vm->m_data[vi] = n_stone;
+                                       if (y > stone_surface_max_y)
+                                               stone_surface_max_y = y;
+                               } else if (y <= water_level) {
+                                       vm->m_data[vi] = n_water;
+                               } else {
+                                       vm->m_data[vi] = n_air;
+                               }
+                       }
+                       vm->m_area.add_y(em, vi, 1);
+               }
+       }
+
+       return stone_surface_max_y;
+}
+
+
+MgStoneType MapgenFlat::generateBiomes(float *heat_map, float *humidity_map)
+{
+       v3s16 em = vm->m_area.getExtent();
+       u32 index = 0;
+       MgStoneType stone_type = STONE;
+
+       for (s16 z = node_min.Z; z <= node_max.Z; z++)
+       for (s16 x = node_min.X; x <= node_max.X; x++, index++) {
+               Biome *biome = NULL;
+               u16 depth_top = 0;
+               u16 base_filler = 0;
+               u16 depth_water_top = 0;
+               u32 vi = vm->m_area.index(x, node_max.Y, z);
+
+               // Check node at base of mapchunk above, either a node of a previously
+               // generated mapchunk or if not, a node of overgenerated base terrain.
+               content_t c_above = vm->m_data[vi + em.X].getContent();
+               bool air_above = c_above == CONTENT_AIR;
+               bool water_above = c_above == c_water_source;
+
+               // If there is air or water above enable top/filler placement, otherwise force
+               // nplaced to stone level by setting a number exceeding any possible filler depth.
+               u16 nplaced = (air_above || water_above) ? 0 : U16_MAX;
+
+
+               for (s16 y = node_max.Y; y >= node_min.Y; y--) {
+                       content_t c = vm->m_data[vi].getContent();
+
+                       // Biome is recalculated each time an upper surface is detected while
+                       // working down a column. The selected biome then remains in effect for
+                       // all nodes below until the next surface and biome recalculation.
+                       // Biome is recalculated:
+                       // 1. At the surface of stone below air or water.
+                       // 2. At the surface of water below air.
+                       // 3. When stone or water is detected but biome has not yet been calculated.
+                       if ((c == c_stone && (air_above || water_above || !biome)) ||
+                                       (c == c_water_source && (air_above || !biome))) {
+                               biome = bmgr->getBiome(heat_map[index], humidity_map[index], y);
+                               depth_top = biome->depth_top;
+                               base_filler = MYMAX(depth_top + biome->depth_filler
+                                       + noise_filler_depth->result[index], 0);
+                               depth_water_top = biome->depth_water_top;
+
+                               // Detect stone type for dungeons during every biome calculation.
+                               // This is more efficient than detecting per-node and will not
+                               // miss any desert stone or sandstone biomes.
+                               if (biome->c_stone == c_desert_stone)
+                                       stone_type = DESERT_STONE;
+                               else if (biome->c_stone == c_sandstone)
+                                       stone_type = SANDSTONE;
+                       }
+
+                       if (c == c_stone) {
+                               content_t c_below = vm->m_data[vi - em.X].getContent();
+
+                               // If the node below isn't solid, make this node stone, so that
+                               // any top/filler nodes above are structurally supported.
+                               // This is done by aborting the cycle of top/filler placement
+                               // immediately by forcing nplaced to stone level.
+                               if (c_below == CONTENT_AIR || c_below == c_water_source)
+                                       nplaced = U16_MAX;
+
+                               if (nplaced < depth_top) {
+                                       vm->m_data[vi] = MapNode(biome->c_top);
+                                       nplaced++;
+                               } else if (nplaced < base_filler) {
+                                       vm->m_data[vi] = MapNode(biome->c_filler);
+                                       nplaced++;
+                               } else {
+                                       vm->m_data[vi] = MapNode(biome->c_stone);
+                               }
+
+                               air_above = false;
+                               water_above = false;
+                       } else if (c == c_water_source) {
+                               vm->m_data[vi] = MapNode((y > (s32)(water_level - depth_water_top)) ?
+                                               biome->c_water_top : biome->c_water);
+                               nplaced = 0;  // Enable top/filler placement for next surface
+                               air_above = false;
+                               water_above = true;
+                       } else if (c == CONTENT_AIR) {
+                               nplaced = 0;  // Enable top/filler placement for next surface
+                               air_above = true;
+                               water_above = false;
+                       } else {  // Possible various nodes overgenerated from neighbouring mapchunks
+                               nplaced = U16_MAX;  // Disable top/filler placement
+                               air_above = false;
+                               water_above = false;
+                       }
+
+                       vm->m_area.add_y(em, vi, -1);
+               }
+       }
+
+       return stone_type;
+}
+
+
+void MapgenFlat::dustTopNodes()
+{
+       if (node_max.Y < water_level)
+               return;
+
+       v3s16 em = vm->m_area.getExtent();
+       u32 index = 0;
+
+       for (s16 z = node_min.Z; z <= node_max.Z; z++)
+       for (s16 x = node_min.X; x <= node_max.X; x++, index++) {
+               Biome *biome = (Biome *)bmgr->getRaw(biomemap[index]);
+
+               if (biome->c_dust == CONTENT_IGNORE)
+                       continue;
+
+               u32 vi = vm->m_area.index(x, full_node_max.Y, z);
+               content_t c_full_max = vm->m_data[vi].getContent();
+               s16 y_start;
+
+               if (c_full_max == CONTENT_AIR) {
+                       y_start = full_node_max.Y - 1;
+               } else if (c_full_max == CONTENT_IGNORE) {
+                       vi = vm->m_area.index(x, node_max.Y + 1, z);
+                       content_t c_max = vm->m_data[vi].getContent();
+
+                       if (c_max == CONTENT_AIR)
+                               y_start = node_max.Y;
+                       else
+                               continue;
+               } else {
+                       continue;
+               }
+
+               vi = vm->m_area.index(x, y_start, z);
+               for (s16 y = y_start; y >= node_min.Y - 1; y--) {
+                       if (vm->m_data[vi].getContent() != CONTENT_AIR)
+                               break;
+
+                       vm->m_area.add_y(em, vi, -1);
+               }
+
+               content_t c = vm->m_data[vi].getContent();
+               if (!ndef->get(c).buildable_to && c != CONTENT_IGNORE && c != biome->c_dust) {
+                       vm->m_area.add_y(em, vi, 1);
+                       vm->m_data[vi] = MapNode(biome->c_dust);
+               }
+       }
+}
+
+
+void MapgenFlat::generateCaves(s16 max_stone_y)
+{
+       if (max_stone_y >= node_min.Y) {
+               u32 index = 0;
+
+               for (s16 z = node_min.Z; z <= node_max.Z; z++)
+               for (s16 y = node_min.Y - 1; y <= node_max.Y + 1; y++) {
+                       u32 vi = vm->m_area.index(node_min.X, y, z);
+                       for (s16 x = node_min.X; x <= node_max.X; x++, vi++, index++) {
+                               float d1 = contour(noise_cave1->result[index]);
+                               float d2 = contour(noise_cave2->result[index]);
+                               if (d1 * d2 > 0.4f) {
+                                       content_t c = vm->m_data[vi].getContent();
+                                       if (!ndef->get(c).is_ground_content || c == CONTENT_AIR)
+                                               continue;
+
+                                       vm->m_data[vi] = MapNode(CONTENT_AIR);
+                               }
+                       }
+               }
+       }
+
+       if (node_max.Y > large_cave_depth)
+               return;
+
+       PseudoRandom ps(blockseed + 21343);
+       u32 bruises_count = (ps.range(1, 4) == 1) ? ps.range(1, 2) : 0;
+       for (u32 i = 0; i < bruises_count; i++) {
+               CaveV5 cave(this, &ps);
+               cave.makeCave(node_min, node_max, max_stone_y);
+       }
+}
diff --git a/src/mapgen_flat.h b/src/mapgen_flat.h
new file mode 100644 (file)
index 0000000..0e15df7
--- /dev/null
@@ -0,0 +1,125 @@
+/*
+Minetest
+Copyright (C) 2010-2015 kwolekr, Ryan Kwolek <kwolekr@minetest.net>
+Copyright (C) 2010-2015 paramat, Matt Gregory
+
+This program is free software; you can redistribute it and/or modify
+it under the terms of the GNU Lesser General Public License as published by
+the Free Software Foundation; either version 2.1 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 Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public License along
+with this program; if not, write to the Free Software Foundation, Inc.,
+51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+*/
+
+#ifndef MAPGEN_FLAT_HEADER
+#define MAPGEN_FLAT_HEADER
+
+#include "mapgen.h"
+
+/////// Mapgen Flat flags
+#define MGFLAT_LAKES 0x01
+#define MGFLAT_HILLS 0x02
+
+class BiomeManager;
+
+extern FlagDesc flagdesc_mapgen_flat[];
+
+
+struct MapgenFlatParams : public MapgenSpecificParams {
+       u32 spflags;
+
+       s16 ground_level;
+       s16 large_cave_depth;
+       float lake_threshold;
+       float lake_steepness;
+       float hill_threshold;
+       float hill_steepness;
+
+       NoiseParams np_terrain;
+       NoiseParams np_filler_depth;
+       NoiseParams np_cave1;
+       NoiseParams np_cave2;
+
+       MapgenFlatParams();
+       ~MapgenFlatParams() {}
+
+       void readParams(const Settings *settings);
+       void writeParams(Settings *settings) const;
+};
+
+class MapgenFlat : public Mapgen {
+public:
+       EmergeManager *m_emerge;
+       BiomeManager *bmgr;
+
+       int ystride;
+       int zstride;
+       u32 spflags;
+
+       v3s16 node_min;
+       v3s16 node_max;
+       v3s16 full_node_min;
+       v3s16 full_node_max;
+
+       s16 ground_level;
+       s16 large_cave_depth;
+       float lake_threshold;
+       float lake_steepness;
+       float hill_threshold;
+       float hill_steepness;
+
+       Noise *noise_terrain;
+       Noise *noise_filler_depth;
+       Noise *noise_cave1;
+       Noise *noise_cave2;
+
+       Noise *noise_heat;
+       Noise *noise_humidity;
+       Noise *noise_heat_blend;
+       Noise *noise_humidity_blend;
+
+       content_t c_stone;
+       content_t c_water_source;
+       content_t c_lava_source;
+       content_t c_desert_stone;
+       content_t c_ice;
+       content_t c_sandstone;
+
+       content_t c_cobble;
+       content_t c_stair_cobble;
+       content_t c_mossycobble;
+       content_t c_sandstonebrick;
+       content_t c_stair_sandstonebrick;
+
+       MapgenFlat(int mapgenid, MapgenParams *params, EmergeManager *emerge);
+       ~MapgenFlat();
+
+       virtual void makeChunk(BlockMakeData *data);
+       int getGroundLevelAtPoint(v2s16 p);
+       void calculateNoise();
+       s16 generateTerrain();
+       MgStoneType generateBiomes(float *heat_map, float *humidity_map);
+       void dustTopNodes();
+       void generateCaves(s16 max_stone_y);
+};
+
+struct MapgenFactoryFlat : public MapgenFactory {
+       Mapgen *createMapgen(int mgid, MapgenParams *params, EmergeManager *emerge)
+       {
+               return new MapgenFlat(mgid, params, emerge);
+       };
+
+       MapgenSpecificParams *createMapgenParams()
+       {
+               return new MapgenFlatParams();
+       };
+};
+
+#endif