From 549cfd9db80c858bdc8d23a237ea57ccf5f68400 Mon Sep 17 00:00:00 2001 From: Paramat Date: Thu, 4 Jan 2018 23:10:55 +0000 Subject: [PATCH] Biomes: Add vertical biome blend (#6853) Add 'vertical blend' parameter to biome registration that defines how many nodes above the biome's 'y max' limit the blend will extend. --- doc/lua_api.txt | 18 ++++++++-------- src/mapgen/mg_biome.cpp | 37 ++++++++++++++++++++++++--------- src/mapgen/mg_biome.h | 1 + src/script/lua_api/l_mapgen.cpp | 1 + 4 files changed, 38 insertions(+), 19 deletions(-) diff --git a/doc/lua_api.txt b/doc/lua_api.txt index 54a5e7b57..432f33ae1 100644 --- a/doc/lua_api.txt +++ b/doc/lua_api.txt @@ -4989,18 +4989,18 @@ Definition tables y_min = 1, y_max = 31000, -- ^ Lower and upper limits for biome. + vertical_blend = 8, + -- ^ Vertical distance in nodes above 'y_max' over which the biome will + -- ^ blend with the biome above. + -- ^ Set to 0 for no vertical blend. Defaults to 0. heat_point = 0, humidity_point = 50, - -- ^ Characteristic average temperature and humidity for the biome. - -- ^ These values create 'biome points' on a voronoi diagram that has heat - -- ^ and humidity as axes. The resulting voronoi cells determine which - -- ^ heat/humidity points belong to which biome, and therefore determine - -- ^ the area and location of each biome in the world. - -- ^ The biome points need to be carefully and evenly spaced on the voronoi - -- ^ diagram to result in roughly equal size biomes. + -- ^ Characteristic temperature and humidity for the biome. + -- ^ These values create 'biome points' on a voronoi diagram with heat and + -- ^ humidity as axes. The resulting voronoi cells determine the + -- ^ distribution of the biomes. -- ^ Heat and humidity have average values of 50, vary mostly between - -- ^ 0 and 100 but also often exceed these values. - -- ^ Heat is not in degrees Celsius, both values are abstract. + -- ^ 0 and 100 but can exceed these values. } ### Decoration definition (`register_decoration`) diff --git a/src/mapgen/mg_biome.cpp b/src/mapgen/mg_biome.cpp index 8dbb78e59..c3493a3d9 100644 --- a/src/mapgen/mg_biome.cpp +++ b/src/mapgen/mg_biome.cpp @@ -50,6 +50,7 @@ BiomeManager::BiomeManager(Server *server) : b->y_max = MAX_MAP_GENERATION_LIMIT; b->heat_point = 0.0; b->humidity_point = 0.0; + b->vertical_blend = 0; b->m_nodenames.emplace_back("mapgen_stone"); b->m_nodenames.emplace_back("mapgen_stone"); @@ -201,25 +202,41 @@ Biome *BiomeGenOriginal::getBiomeAtIndex(size_t index, s16 y) const Biome *BiomeGenOriginal::calcBiomeFromNoise(float heat, float humidity, s16 y) const { - Biome *b, *biome_closest = NULL; + Biome *biome_closest = nullptr; + Biome *biome_closest_blend = nullptr; float dist_min = FLT_MAX; + float dist_min_blend = FLT_MAX; for (size_t i = 1; i < m_bmgr->getNumObjects(); i++) { - b = (Biome *)m_bmgr->getRaw(i); - if (!b || y > b->y_max || y < b->y_min) + Biome *b = (Biome *)m_bmgr->getRaw(i); + if (!b || y > b->y_max + b->vertical_blend || y < b->y_min) continue; - float d_heat = heat - b->heat_point; + float d_heat = heat - b->heat_point; float d_humidity = humidity - b->humidity_point; - float dist = (d_heat * d_heat) + - (d_humidity * d_humidity); - if (dist < dist_min) { - dist_min = dist; - biome_closest = b; + float dist = (d_heat * d_heat) + (d_humidity * d_humidity); + + if (y <= b->y_max) { // Within y limits of biome b + if (dist < dist_min) { + dist_min = dist; + biome_closest = b; + } + } else if (dist < dist_min_blend) { // Blend area above biome b + dist_min_blend = dist; + biome_closest_blend = b; } } - return biome_closest ? biome_closest : (Biome *)m_bmgr->getRaw(BIOME_NONE); + // Carefully tune pseudorandom seed variation to avoid single node dither + // and create larger scale blending patterns. + mysrand(y + (heat - humidity) * 2); + + if (biome_closest_blend && + myrand_range(0, biome_closest_blend->vertical_blend) >= + y - biome_closest_blend->y_max) + return biome_closest_blend; + + return (biome_closest) ? biome_closest : (Biome *)m_bmgr->getRaw(BIOME_NONE); } diff --git a/src/mapgen/mg_biome.h b/src/mapgen/mg_biome.h index f45238f28..0f3fd76a9 100644 --- a/src/mapgen/mg_biome.h +++ b/src/mapgen/mg_biome.h @@ -67,6 +67,7 @@ public: s16 y_max; float heat_point; float humidity_point; + s16 vertical_blend; virtual void resolveNodeNames(); }; diff --git a/src/script/lua_api/l_mapgen.cpp b/src/script/lua_api/l_mapgen.cpp index e39370323..b526111d4 100644 --- a/src/script/lua_api/l_mapgen.cpp +++ b/src/script/lua_api/l_mapgen.cpp @@ -392,6 +392,7 @@ Biome *read_biome_def(lua_State *L, int index, INodeDefManager *ndef) b->y_max = getintfield_default(L, index, "y_max", 31000); b->heat_point = getfloatfield_default(L, index, "heat_point", 0.f); b->humidity_point = getfloatfield_default(L, index, "humidity_point", 0.f); + b->vertical_blend = getintfield_default(L, index, "vertical_blend", 0); b->flags = 0; //reserved std::vector &nn = b->m_nodenames;