mirror of https://github.com/minetest/minetest.git
Mapgen Carpathian: Add optional rivers (#7977)
Rivers are disabled by default and will not be added to existing worlds. Rewrite getSpawnLevelAtPoint() to be simpler and more consistent with generateTerrain().
This commit is contained in:
Paramat
GitHub
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95a37efc31
commit
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@ -1578,11 +1578,20 @@ mgv7_np_dungeons (Dungeon noise) noise_params_3d 0.9, 0.5, (500, 500, 500), 0, 2
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[*Mapgen Carpathian]
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# Map generation attributes specific to Mapgen Carpathian.
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mgcarpathian_spflags (Mapgen Carpathian specific flags) flags caverns caverns,nocaverns
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mgcarpathian_spflags (Mapgen Carpathian specific flags) flags caverns,norivers caverns,nocaverns,rivers,norivers
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# Defines the base ground level.
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mgcarpathian_base_level (Base ground level) float 12.0
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# Defines the width of the river channel.
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mgcarpathian_river_width (River channel width) float 0.05
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# Defines the depth of the river channel.
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mgcarpathian_river_depth (River channel depth) float 24.0
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# Defines the width of the river valley.
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mgcarpathian_valley_width (River valley width) float 0.25
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# Controls width of tunnels, a smaller value creates wider tunnels.
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mgcarpathian_cave_width (Cave width) float 0.09
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@ -1642,6 +1651,9 @@ mgcarpathian_np_ridge_mnt (Ridged mountain size noise) noise_params_2d 0, 12, (7
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# 2D noise that controls the shape/size of step mountains.
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mgcarpathian_np_step_mnt (Step mountain size noise) noise_params_2d 0, 8, (509, 509, 509), 2590, 6, 0.6, 2.0, eased
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# 2D noise that locates the river valleys and channels.
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mgcarpathian_np_rivers (River noise) noise_params_2d 0, 1, (1000, 1000, 1000), 85039, 5, 0.6, 2.0, eased
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# 3D noise for mountain overhangs, cliffs, etc. Usually small variations.
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mgcarpathian_np_mnt_var (Mountain variation noise) noise_params_3d 0, 1, (499, 499, 499), 2490, 5, 0.55, 2.0
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@ -1,8 +1,7 @@
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/*
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Minetest
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Copyright (C) 2017-2018 vlapsley, Vaughan Lapsley <vlapsley@gmail.com>
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Copyright (C) 2010-2018 paramat
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Copyright (C) 2010-2018 kwolekr, Ryan Kwolek <kwolekr@minetest.net>
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Copyright (C) 2017-2019 vlapsley, Vaughan Lapsley <vlapsley@gmail.com>
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Copyright (C) 2017-2019 paramat
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU Lesser General Public License as published by
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@ -43,6 +42,7 @@ with this program; if not, write to the Free Software Foundation, Inc.,
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FlagDesc flagdesc_mapgen_carpathian[] = {
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{"caverns", MGCARPATHIAN_CAVERNS},
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{"rivers", MGCARPATHIAN_RIVERS},
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{NULL, 0}
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};
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@ -54,6 +54,9 @@ MapgenCarpathian::MapgenCarpathian(MapgenCarpathianParams *params, EmergeManager
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: MapgenBasic(MAPGEN_CARPATHIAN, params, emerge)
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{
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base_level = params->base_level;
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river_width = params->river_width;
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river_depth = params->river_depth;
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valley_width = params->valley_width;
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spflags = params->spflags;
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cave_width = params->cave_width;
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@ -79,6 +82,8 @@ MapgenCarpathian::MapgenCarpathian(MapgenCarpathianParams *params, EmergeManager
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noise_hills = new Noise(¶ms->np_hills, seed, csize.X, csize.Z);
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noise_ridge_mnt = new Noise(¶ms->np_ridge_mnt, seed, csize.X, csize.Z);
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noise_step_mnt = new Noise(¶ms->np_step_mnt, seed, csize.X, csize.Z);
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if (spflags & MGCARPATHIAN_RIVERS)
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noise_rivers = new Noise(¶ms->np_rivers, seed, csize.X, csize.Z);
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//// 3D terrain noise
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// 1 up 1 down overgeneration
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@ -105,6 +110,9 @@ MapgenCarpathian::~MapgenCarpathian()
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delete noise_hills;
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delete noise_ridge_mnt;
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delete noise_step_mnt;
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if (spflags & MGCARPATHIAN_RIVERS)
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delete noise_rivers;
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delete noise_mnt_var;
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}
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@ -121,6 +129,7 @@ MapgenCarpathianParams::MapgenCarpathianParams():
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np_hills (0, 3, v3f(257, 257, 257), 6604, 6, 0.5, 2.0),
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np_ridge_mnt (0, 12, v3f(743, 743, 743), 5520, 6, 0.7, 2.0),
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np_step_mnt (0, 8, v3f(509, 509, 509), 2590, 6, 0.6, 2.0),
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np_rivers (0, 1, v3f(1000, 1000, 1000), 85039, 5, 0.6, 2.0),
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np_mnt_var (0, 1, v3f(499, 499, 499), 2490, 5, 0.55, 2.0),
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np_cave1 (0, 12, v3f(61, 61, 61), 52534, 3, 0.5, 2.0),
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np_cave2 (0, 12, v3f(67, 67, 67), 10325, 3, 0.5, 2.0),
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@ -133,7 +142,12 @@ MapgenCarpathianParams::MapgenCarpathianParams():
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void MapgenCarpathianParams::readParams(const Settings *settings)
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{
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settings->getFlagStrNoEx("mgcarpathian_spflags", spflags, flagdesc_mapgen_carpathian);
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settings->getFloatNoEx("mgcarpathian_base_level", base_level);
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settings->getFloatNoEx("mgcarpathian_base_level", base_level);
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settings->getFloatNoEx("mgcarpathian_river_width", river_width);
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settings->getFloatNoEx("mgcarpathian_river_depth", river_depth);
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settings->getFloatNoEx("mgcarpathian_valley_width", valley_width);
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settings->getFloatNoEx("mgcarpathian_cave_width", cave_width);
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settings->getS16NoEx("mgcarpathian_large_cave_depth", large_cave_depth);
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settings->getS16NoEx("mgcarpathian_lava_depth", lava_depth);
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@ -154,6 +168,7 @@ void MapgenCarpathianParams::readParams(const Settings *settings)
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settings->getNoiseParams("mgcarpathian_np_hills", np_hills);
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settings->getNoiseParams("mgcarpathian_np_ridge_mnt", np_ridge_mnt);
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settings->getNoiseParams("mgcarpathian_np_step_mnt", np_step_mnt);
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settings->getNoiseParams("mgcarpathian_np_rivers", np_rivers);
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settings->getNoiseParams("mgcarpathian_np_mnt_var", np_mnt_var);
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settings->getNoiseParams("mgcarpathian_np_cave1", np_cave1);
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settings->getNoiseParams("mgcarpathian_np_cave2", np_cave2);
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@ -165,7 +180,12 @@ void MapgenCarpathianParams::readParams(const Settings *settings)
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void MapgenCarpathianParams::writeParams(Settings *settings) const
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{
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settings->setFlagStr("mgcarpathian_spflags", spflags, flagdesc_mapgen_carpathian, U32_MAX);
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settings->setFloat("mgcarpathian_base_level", base_level);
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settings->setFloat("mgcarpathian_base_level", base_level);
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settings->setFloat("mgcarpathian_river_width", river_width);
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settings->setFloat("mgcarpathian_river_depth", river_depth);
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settings->setFloat("mgcarpathian_valley_width", valley_width);
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settings->setFloat("mgcarpathian_cave_width", cave_width);
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settings->setS16("mgcarpathian_large_cave_depth", large_cave_depth);
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settings->setS16("mgcarpathian_lava_depth", lava_depth);
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@ -186,6 +206,7 @@ void MapgenCarpathianParams::writeParams(Settings *settings) const
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settings->setNoiseParams("mgcarpathian_np_hills", np_hills);
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settings->setNoiseParams("mgcarpathian_np_ridge_mnt", np_ridge_mnt);
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settings->setNoiseParams("mgcarpathian_np_step_mnt", np_step_mnt);
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settings->setNoiseParams("mgcarpathian_np_rivers", np_rivers);
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settings->setNoiseParams("mgcarpathian_np_mnt_var", np_mnt_var);
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settings->setNoiseParams("mgcarpathian_np_cave1", np_cave1);
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settings->setNoiseParams("mgcarpathian_np_cave2", np_cave2);
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@ -310,64 +331,95 @@ void MapgenCarpathian::makeChunk(BlockMakeData *data)
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int MapgenCarpathian::getSpawnLevelAtPoint(v2s16 p)
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{
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s16 level_at_point = terrainLevelAtPoint(p.X, p.Y);
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if (level_at_point <= water_level || level_at_point > water_level + 32)
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return MAX_MAP_GENERATION_LIMIT; // Unsuitable spawn point
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// If rivers are enabled, first check if in a river channel
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if (spflags & MGCARPATHIAN_RIVERS) {
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float river = std::fabs(NoisePerlin2D(&noise_rivers->np, p.X, p.Y, seed)) -
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river_width;
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if (river < 0.0f)
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return MAX_MAP_GENERATION_LIMIT; // Unsuitable spawn point
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}
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return level_at_point;
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}
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float height1 = NoisePerlin2D(&noise_height1->np, p.X, p.Y, seed);
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float height2 = NoisePerlin2D(&noise_height2->np, p.X, p.Y, seed);
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float height3 = NoisePerlin2D(&noise_height3->np, p.X, p.Y, seed);
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float height4 = NoisePerlin2D(&noise_height4->np, p.X, p.Y, seed);
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float hterabs = std::fabs(NoisePerlin2D(&noise_hills_terrain->np, p.X, p.Y, seed));
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float n_hills = NoisePerlin2D(&noise_hills->np, p.X, p.Y, seed);
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float hill_mnt = hterabs * hterabs * hterabs * n_hills * n_hills;
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float MapgenCarpathian::terrainLevelAtPoint(s16 x, s16 z)
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{
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float height1 = NoisePerlin2D(&noise_height1->np, x, z, seed);
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float height2 = NoisePerlin2D(&noise_height2->np, x, z, seed);
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float height3 = NoisePerlin2D(&noise_height3->np, x, z, seed);
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float height4 = NoisePerlin2D(&noise_height4->np, x, z, seed);
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float hter = NoisePerlin2D(&noise_hills_terrain->np, x, z, seed);
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float rter = NoisePerlin2D(&noise_ridge_terrain->np, x, z, seed);
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float ster = NoisePerlin2D(&noise_step_terrain->np, x, z, seed);
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float n_hills = NoisePerlin2D(&noise_hills->np, x, z, seed);
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float n_ridge_mnt = NoisePerlin2D(&noise_ridge_mnt->np, x, z, seed);
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float n_step_mnt = NoisePerlin2D(&noise_step_mnt->np, x, z, seed);
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float rterabs = std::fabs(NoisePerlin2D(&noise_ridge_terrain->np, p.X, p.Y, seed));
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float n_ridge_mnt = NoisePerlin2D(&noise_ridge_mnt->np, p.X, p.Y, seed);
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float ridge_mnt = rterabs * rterabs * rterabs * (1.0f - std::fabs(n_ridge_mnt));
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int height = -MAX_MAP_GENERATION_LIMIT;
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float sterabs = std::fabs(NoisePerlin2D(&noise_step_terrain->np, p.X, p.Y, seed));
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float n_step_mnt = NoisePerlin2D(&noise_step_mnt->np, p.X, p.Y, seed);
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float step_mnt = sterabs * sterabs * sterabs * getSteps(n_step_mnt);
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for (s16 y = 1; y <= 30; y++) {
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float mnt_var = NoisePerlin3D(&noise_mnt_var->np, x, y, z, seed);
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float valley = 1.0f;
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float river = 0.0f;
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// Gradient & shallow seabed
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s32 grad = (y < water_level) ? grad_wl + (water_level - y) * 3 : 1 - y;
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if ((spflags & MGCARPATHIAN_RIVERS) && node_max.Y >= water_level - 16) {
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river = std::fabs(NoisePerlin2D(&noise_rivers->np, p.X, p.Y, seed)) - river_width;
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if (river <= valley_width) {
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// Within river valley
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if (river < 0.0f) {
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// River channel
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valley = river;
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} else {
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// Valley slopes.
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// 0 at river edge, 1 at valley edge.
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float riversc = river / valley_width;
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// Smoothstep
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valley = riversc * riversc * (3.0f - 2.0f * riversc);
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}
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}
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}
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// Hill/Mountain height (hilliness)
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bool solid_below = false;
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u8 cons_non_solid = 0; // consecutive non-solid nodes
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for (s16 y = water_level; y <= water_level + 32; y++) {
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float mnt_var = NoisePerlin3D(&noise_mnt_var->np, p.X, y, p.Y, seed);
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float hill1 = getLerp(height1, height2, mnt_var);
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float hill2 = getLerp(height3, height4, mnt_var);
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float hill3 = getLerp(height3, height2, mnt_var);
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float hill4 = getLerp(height1, height4, mnt_var);
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float hilliness =
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std::fmax(std::fmin(hill1, hill2), std::fmin(hill3, hill4));
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// Rolling hills
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float hill_mnt = hilliness * std::pow(n_hills, 2.f);
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float hills = std::pow(std::fabs(hter), 3.f) * hill_mnt;
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float hilliness = std::fmax(std::fmin(hill1, hill2), std::fmin(hill3, hill4));
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float hills = hill_mnt * hilliness;
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float ridged_mountains = ridge_mnt * hilliness;
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float step_mountains = step_mnt * hilliness;
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// Ridged mountains
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float ridge_mnt = hilliness * (1.f - std::fabs(n_ridge_mnt));
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float ridged_mountains = std::pow(std::fabs(rter), 3.f) * ridge_mnt;
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s32 grad = 1 - y;
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// Step (terraced) mountains
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float step_mnt = hilliness * getSteps(n_step_mnt);
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float step_mountains = std::pow(std::fabs(ster), 3.f) * step_mnt;
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// Final terrain level
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float mountains = hills + ridged_mountains + step_mountains;
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float surface_level = base_level + mountains + grad;
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if (y > surface_level && height < 0)
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height = y;
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if ((spflags & MGCARPATHIAN_RIVERS) && river <= valley_width) {
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if (valley < 0.0f) {
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// River channel
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surface_level = std::fmin(surface_level,
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water_level - std::sqrt(-valley) * river_depth);
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} else if (surface_level > water_level) {
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// Valley slopes
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surface_level = water_level + (surface_level - water_level) * valley;
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}
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}
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if (y < surface_level) { //TODO '<=' fix from generateTerrain()
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// solid node
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solid_below = true;
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cons_non_solid = 0;
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} else {
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// non-solid node
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cons_non_solid++;
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if (cons_non_solid == 3 && solid_below)
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return y - 1;
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}
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}
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return height;
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return MAX_MAP_GENERATION_LIMIT; // No suitable spawn point found
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}
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@ -393,6 +445,9 @@ int MapgenCarpathian::generateTerrain()
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noise_step_mnt->perlinMap2D(node_min.X, node_min.Z);
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noise_mnt_var->perlinMap3D(node_min.X, node_min.Y - 1, node_min.Z);
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if (spflags & MGCARPATHIAN_RIVERS)
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noise_rivers->perlinMap2D(node_min.X, node_min.Z);
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//// Place nodes
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const v3s16 &em = vm->m_area.getExtent();
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s16 stone_surface_max_y = -MAX_MAP_GENERATION_LIMIT;
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@ -415,13 +470,34 @@ int MapgenCarpathian::generateTerrain()
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float rterabs = std::fabs(noise_ridge_terrain->result[index2d]);
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float n_ridge_mnt = noise_ridge_mnt->result[index2d];
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float ridge_mnt = rterabs * rterabs * rterabs *
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(1.f - std::fabs(n_ridge_mnt));
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(1.0f - std::fabs(n_ridge_mnt));
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// Step (terraced) mountains
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float sterabs = std::fabs(noise_step_terrain->result[index2d]);
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float n_step_mnt = noise_step_mnt->result[index2d];
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float step_mnt = sterabs * sterabs * sterabs * getSteps(n_step_mnt);
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// Rivers
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float valley = 1.0f;
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float river = 0.0f;
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if ((spflags & MGCARPATHIAN_RIVERS) && node_max.Y >= water_level - 16) {
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river = std::fabs(noise_rivers->result[index2d]) - river_width;
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if (river <= valley_width) {
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// Within river valley
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if (river < 0.0f) {
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// River channel
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valley = river;
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} else {
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// Valley slopes.
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// 0 at river edge, 1 at valley edge.
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float riversc = river / valley_width;
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// Smoothstep
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valley = riversc * riversc * (3.0f - 2.0f * riversc);
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}
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}
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}
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// Initialise 3D noise index and voxelmanip index to column base
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u32 index3d = (z - node_min.Z) * zstride_1u1d + (x - node_min.X);
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u32 vi = vm->m_area.index(x, node_min.Y - 1, z);
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@ -456,7 +532,20 @@ int MapgenCarpathian::generateTerrain()
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float mountains = hills + ridged_mountains + step_mountains;
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float surface_level = base_level + mountains + grad;
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if (y < surface_level) {
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// Rivers
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if ((spflags & MGCARPATHIAN_RIVERS) && node_max.Y >= water_level - 16 &&
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river <= valley_width) {
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if (valley < 0.0f) {
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// River channel
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surface_level = std::fmin(surface_level,
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water_level - std::sqrt(-valley) * river_depth);
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} else if (surface_level > water_level) {
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// Valley slopes
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surface_level = water_level + (surface_level - water_level) * valley;
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}
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}
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if (y < surface_level) { //TODO '<='
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vm->m_data[vi] = mn_stone; // Stone
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if (y > stone_surface_max_y)
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stone_surface_max_y = y;
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@ -1,8 +1,7 @@
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/*
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Minetest
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Copyright (C) 2017-2018 vlapsley, Vaughan Lapsley <vlapsley@gmail.com>
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Copyright (C) 2010-2018 paramat
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Copyright (C) 2010-2018 kwolekr, Ryan Kwolek <kwolekr@minetest.net>
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Copyright (C) 2017-2019 vlapsley, Vaughan Lapsley <vlapsley@gmail.com>
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Copyright (C) 2017-2019 paramat
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|
||||
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
|
||||
|
|
@ -23,8 +22,8 @@ with this program; if not, write to the Free Software Foundation, Inc.,
|
|||
|
||||
#include "mapgen.h"
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||||
|
||||
///////// Mapgen Carpathian flags
|
||||
#define MGCARPATHIAN_CAVERNS 0x01
|
||||
#define MGCARPATHIAN_RIVERS 0x02
|
||||
|
||||
class BiomeManager;
|
||||
|
||||
|
|
@ -34,6 +33,9 @@ extern FlagDesc flagdesc_mapgen_carpathian[];
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|||
struct MapgenCarpathianParams : public MapgenParams
|
||||
{
|
||||
float base_level = 12.0f;
|
||||
float river_width = 0.05f;
|
||||
float river_depth = 24.0f;
|
||||
float valley_width = 0.25f;
|
||||
|
||||
u32 spflags = MGCARPATHIAN_CAVERNS;
|
||||
float cave_width = 0.09f;
|
||||
|
|
@ -56,6 +58,7 @@ struct MapgenCarpathianParams : public MapgenParams
|
|||
NoiseParams np_hills;
|
||||
NoiseParams np_ridge_mnt;
|
||||
NoiseParams np_step_mnt;
|
||||
NoiseParams np_rivers;
|
||||
NoiseParams np_mnt_var;
|
||||
NoiseParams np_cave1;
|
||||
NoiseParams np_cave2;
|
||||
|
|
@ -77,15 +80,14 @@ public:
|
|||
|
||||
virtual MapgenType getType() const { return MAPGEN_CARPATHIAN; }
|
||||
|
||||
float getSteps(float noise);
|
||||
inline float getLerp(float noise1, float noise2, float mod);
|
||||
|
||||
virtual void makeChunk(BlockMakeData *data);
|
||||
int getSpawnLevelAtPoint(v2s16 p);
|
||||
|
||||
private:
|
||||
float base_level;
|
||||
s32 grad_wl;
|
||||
float river_width;
|
||||
float river_depth;
|
||||
float valley_width;
|
||||
|
||||
s16 large_cave_depth;
|
||||
s16 dungeon_ymin;
|
||||
|
|
@ -101,8 +103,12 @@ private:
|
|||
Noise *noise_hills;
|
||||
Noise *noise_ridge_mnt;
|
||||
Noise *noise_step_mnt;
|
||||
Noise *noise_rivers = nullptr;
|
||||
Noise *noise_mnt_var;
|
||||
|
||||
float terrainLevelAtPoint(s16 x, s16 z);
|
||||
s32 grad_wl;
|
||||
|
||||
float getSteps(float noise);
|
||||
inline float getLerp(float noise1, float noise2, float mod);
|
||||
int generateTerrain();
|
||||
};
|
||||
|
|
|
|||
Loading…
Reference in New Issue