Avoid crash caused by, and improve, 'findSpawnPos()' (#8728)
[oweals/minetest.git] / src / mapgen / mapgen_fractal.cpp
index 10397f7b824f1da5b4cbe33541cc5e2c68a016f0..091dbacfa28e9044e35d3a7a851d53a5833af657 100644 (file)
@@ -1,7 +1,7 @@
 /*
 Minetest
-Copyright (C) 2015-2018 paramat
-Copyright (C) 2015-2018 kwolekr, Ryan Kwolek <kwolekr@minetest.net>
+Copyright (C) 2015-2019 paramat
+Copyright (C) 2015-2016 kwolekr, Ryan Kwolek
 
 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
@@ -41,14 +41,15 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 
 
 FlagDesc flagdesc_mapgen_fractal[] = {
-       {NULL,    0}
+       {"terrain", MGFRACTAL_TERRAIN},
+       {NULL,      0}
 };
 
 ///////////////////////////////////////////////////////////////////////////////////////
 
 
-MapgenFractal::MapgenFractal(int mapgenid, MapgenFractalParams *params, EmergeManager *emerge)
-       : MapgenBasic(mapgenid, params, emerge)
+MapgenFractal::MapgenFractal(MapgenFractalParams *params, EmergeManager *emerge)
+       : MapgenBasic(MAPGEN_FRACTAL, params, emerge)
 {
        spflags          = params->spflags;
        cave_width       = params->cave_width;
@@ -66,12 +67,17 @@ MapgenFractal::MapgenFractal(int mapgenid, MapgenFractalParams *params, EmergeMa
        julia_z          = params->julia_z;
        julia_w          = params->julia_w;
 
-       //// 2D terrain noise
-       noise_seabed       = new Noise(&params->np_seabed, seed, csize.X, csize.Z);
+       //// 2D noise
+       if (spflags & MGFRACTAL_TERRAIN)
+               noise_seabed = new Noise(&params->np_seabed, seed, csize.X, csize.Z);
+
        noise_filler_depth = new Noise(&params->np_filler_depth, seed, csize.X, csize.Z);
 
-       MapgenBasic::np_cave1 = params->np_cave1;
-       MapgenBasic::np_cave2 = params->np_cave2;
+       //// 3D noise
+       MapgenBasic::np_dungeons = params->np_dungeons;
+       // Overgeneration to node_min.Y - 1
+       MapgenBasic::np_cave1    = params->np_cave1;
+       MapgenBasic::np_cave2    = params->np_cave2;
 
        formula = fractal / 2 + fractal % 2;
        julia   = fractal % 2 == 0;
@@ -80,7 +86,9 @@ MapgenFractal::MapgenFractal(int mapgenid, MapgenFractalParams *params, EmergeMa
 
 MapgenFractal::~MapgenFractal()
 {
-       delete noise_seabed;
+       if (noise_seabed)
+               delete noise_seabed;
+
        delete noise_filler_depth;
 }
 
@@ -89,7 +97,8 @@ MapgenFractalParams::MapgenFractalParams():
        np_seabed       (-14, 9,   v3f(600, 600, 600), 41900, 5, 0.6, 2.0),
        np_filler_depth (0,   1.2, v3f(150, 150, 150), 261,   3, 0.7, 2.0),
        np_cave1        (0,   12,  v3f(61,  61,  61),  52534, 3, 0.5, 2.0),
-       np_cave2        (0,   12,  v3f(67,  67,  67),  10325, 3, 0.5, 2.0)
+       np_cave2        (0,   12,  v3f(67,  67,  67),  10325, 3, 0.5, 2.0),
+       np_dungeons     (0.9, 0.5, v3f(500, 500, 500), 0,     2, 0.8, 2.0)
 {
 }
 
@@ -116,6 +125,7 @@ void MapgenFractalParams::readParams(const Settings *settings)
        settings->getNoiseParams("mgfractal_np_filler_depth", np_filler_depth);
        settings->getNoiseParams("mgfractal_np_cave1",        np_cave1);
        settings->getNoiseParams("mgfractal_np_cave2",        np_cave2);
+       settings->getNoiseParams("mgfractal_np_dungeons",     np_dungeons);
 }
 
 
@@ -141,6 +151,7 @@ void MapgenFractalParams::writeParams(Settings *settings) const
        settings->setNoiseParams("mgfractal_np_filler_depth", np_filler_depth);
        settings->setNoiseParams("mgfractal_np_cave1",        np_cave1);
        settings->setNoiseParams("mgfractal_np_cave2",        np_cave2);
+       settings->setNoiseParams("mgfractal_np_dungeons",     np_dungeons);
 }
 
 
@@ -149,21 +160,25 @@ void MapgenFractalParams::writeParams(Settings *settings) const
 
 int MapgenFractal::getSpawnLevelAtPoint(v2s16 p)
 {
-       bool solid_below = false;  // Dry solid node is present below to spawn on
-       u8 air_count = 0;  // Consecutive air nodes above the dry solid node
-       s16 seabed_level = NoisePerlin2D(&noise_seabed->np, p.X, p.Y, seed);
-       // Seabed can rise above water_level or might be raised to create dry land
-       s16 search_start = MYMAX(seabed_level, water_level + 1);
-       if (seabed_level > water_level)
-               solid_below = true;
-
-       for (s16 y = search_start; y <= search_start + 128; y++) {
-               if (getFractalAtPoint(p.X, y, p.Y)) {  // Fractal node
+       bool solid_below = false; // Fractal node is present below to spawn on
+       u8 air_count = 0; // Consecutive air nodes above a fractal node
+       s16 search_start = 0; // No terrain search start
+
+       // If terrain present, don't start search below terrain or water level
+       if (noise_seabed) {
+               s16 seabed_level = NoisePerlin2D(&noise_seabed->np, p.X, p.Y, seed);
+               search_start = MYMAX(search_start, MYMAX(seabed_level, water_level));
+       }
+
+       for (s16 y = search_start; y <= search_start + 4096; y++) {
+               if (getFractalAtPoint(p.X, y, p.Y)) {
+                       // Fractal node
                        solid_below = true;
                        air_count = 0;
-               } else if (solid_below) {  // Air above solid node
+               } else if (solid_below) {
+                       // Air above fractal node
                        air_count++;
-                       // 3 to account for snowblock dust
+                       // 3 and -2 to account for biome dust nodes
                        if (air_count == 3)
                                return y - 2;
                }
@@ -185,10 +200,11 @@ void MapgenFractal::makeChunk(BlockMakeData *data)
                data->blockpos_requested.Y <= data->blockpos_max.Y &&
                data->blockpos_requested.Z <= data->blockpos_max.Z);
 
+       //TimeTaker t("makeChunk");
+
        this->generating = true;
-       this->vm   = data->vmanip;
+       this->vm = data->vmanip;
        this->ndef = data->nodedef;
-       //TimeTaker t("makeChunk");
 
        v3s16 blockpos_min = data->blockpos_min;
        v3s16 blockpos_max = data->blockpos_max;
@@ -199,19 +215,28 @@ void MapgenFractal::makeChunk(BlockMakeData *data)
 
        blockseed = getBlockSeed2(full_node_min, seed);
 
-       // Generate base terrain, mountains, and ridges with initial heightmaps
+       // Generate fractal and optional terrain
        s16 stone_surface_max_y = generateTerrain();
 
        // Create heightmap
        updateHeightmap(node_min, node_max);
 
        // Init biome generator, place biome-specific nodes, and build biomemap
-       biomegen->calcBiomeNoise(node_min);
-       generateBiomes();
+       if (flags & MG_BIOMES) {
+               biomegen->calcBiomeNoise(node_min);
+               generateBiomes();
+       }
+
+       // Generate tunnels and randomwalk caves
+       if (flags & MG_CAVES) {
+               generateCavesNoiseIntersection(stone_surface_max_y);
+               generateCavesRandomWalk(stone_surface_max_y, large_cave_depth);
+       }
 
-       if (flags & MG_CAVES)
-               generateCaves(stone_surface_max_y, large_cave_depth);
+       // Generate the registered ores
+       m_emerge->oremgr->placeAllOres(this, blockseed, node_min, node_max);
 
+       // Generate dungeons
        if ((flags & MG_DUNGEONS) && full_node_min.Y >= dungeon_ymin &&
                        full_node_max.Y <= dungeon_ymax)
                generateDungeons(stone_surface_max_y);
@@ -220,24 +245,22 @@ void MapgenFractal::makeChunk(BlockMakeData *data)
        if (flags & MG_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());
+       if (flags & MG_BIOMES)
+               dustTopNodes();
 
-       updateLiquid(&data->transforming_liquid, full_node_min, full_node_max);
+       // Update liquids
+       if (spflags & MGFRACTAL_TERRAIN)
+               updateLiquid(&data->transforming_liquid, full_node_min, full_node_max);
 
+       // Calculate lighting
        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;
+
+       //printf("makeChunk: %lums\n", t.stop());
 }
 
 
@@ -380,24 +403,29 @@ s16 MapgenFractal::generateTerrain()
        s16 stone_surface_max_y = -MAX_MAP_GENERATION_LIMIT;
        u32 index2d = 0;
 
-       noise_seabed->perlinMap2D(node_min.X, node_min.Z);
+       if (noise_seabed)
+               noise_seabed->perlinMap2D(node_min.X, node_min.Z);
 
        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++, index2d++) {
-                               if (vm->m_data[vi].getContent() == CONTENT_IGNORE) {
-                                       s16 seabed_height = noise_seabed->result[index2d];
-
-                                       if (y <= seabed_height || getFractalAtPoint(x, y, z)) {
-                                               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;
-                                       }
+                               if (vm->m_data[vi].getContent() != CONTENT_IGNORE)
+                                       continue;
+
+                               s16 seabed_height = -MAX_MAP_GENERATION_LIMIT;
+                               if (noise_seabed)
+                                       seabed_height = noise_seabed->result[index2d];
+
+                               if (((spflags & MGFRACTAL_TERRAIN) && y <= seabed_height) ||
+                                               getFractalAtPoint(x, y, z)) {
+                                       vm->m_data[vi] = n_stone;
+                                       if (y > stone_surface_max_y)
+                                               stone_surface_max_y = y;
+                               } else if ((spflags & MGFRACTAL_TERRAIN) && y <= water_level) {
+                                       vm->m_data[vi] = n_water;
+                               } else {
+                                       vm->m_data[vi] = n_air;
                                }
                        }
                        index2d -= ystride;