Pretty terrain generation

1 files changed, 59 insertions, 0 deletions

diff --git a/src/World/Generator.hpp b/src/World/Generator.hpp
index afe43c6..523136a 100644
--- a/src/World/Generator.hpp
+++ b/src/World/Generator.hpp
@@ -3,6 +3,7 @@
 #include <cstdint>
 #include "Chunk.hpp"
 #include "BiomeType.hpp"
+#include "../Math/Perlin.hpp"
 
 namespace MC::World {
 
@@ -10,6 +11,64 @@ class Generator {
 public:
     Generator() = default;
     Chunk generate(int64_t chunk_x, int64_t chunk_y);
+private:
+    template <typename V>
+    struct ChunkMap2D {
+        V map[Chunk::Width * Chunk::Width];
+        void set(uint x, uint y, V v) { map[x * Chunk::Width + y] = v; }
+        V get(uint x, uint y) { return map[x * Chunk::Width + y]; }
+    };
+
+    template <typename V>
+    struct ChunkMap3D {
+        V map[Chunk::Width * Chunk::Width * Chunk::Height];
+        void set(uint x, uint y, uint z, V v) { map[pos(x, y, z)] = v; }
+        V get(uint x, uint y, uint z) { return map[pos(x, y, z)]; }
+        static uint pos(uint x, uint y, uint z) { return x + Chunk::Width * y + Chunk::Width * Chunk::Height * z; }
+    };
+
+    ChunkMap2D<float> generate_landmass_map(int64_t chunk_x, int64_t chunk_y);
+    ChunkMap2D<float> generate_hill_map(int64_t chunk_x, int64_t chunk_y);
+    ChunkMap2D<float> generate_height_map(ChunkMap2D<float>& landmass_map, ChunkMap2D<float>& hill_map, int64_t chunk_x, int64_t chunk_y);
+
+    ChunkMap2D<BiomeType> generate_biome_map(ChunkMap2D<float>& landmass_map, ChunkMap2D<float>& hill_map, ChunkMap2D<float>& height_map, int64_t chunk_x, int64_t chunk_y);
+
+    ChunkMap3D<bool> generate_terrain(ChunkMap2D<float>& height_map, int64_t chunk_x, int64_t chunk_y);
+
+    void decorate_soil(Chunk& chunk, ChunkMap2D<BiomeType>& biome_map, ChunkMap3D<bool>& terrain_map);
+
+    [[nodiscard]] float get_landmass(Vector<2> pos) const;
+    [[nodiscard]] float get_hill(Vector<2> pos) const;
+
+    [[nodiscard]] float get_humidity(Vector<2> pos) const;
+    [[nodiscard]] float get_temperature(Vector<2> pos) const;
+
+    [[nodiscard]] float get_density(Vector<3> pos) const;
+
+    static Vector<2> chunk_position_to_world_vector(int64_t chunk_x, int64_t chunk_y, uint x, uint y);
+
+    Math::Perlin::Noise<2> m_landmass_noise{.scale=800.0f, .octaves=4, .persistence=0.3f, .lacunarity=3.5f};
+    Math::Perlin::Noise<2> m_hill_noise{.scale=400.0f, .octaves=3, .persistence=0.5f, .lacunarity=2.0f};
+
+    Math::Perlin::Noise<2> m_temperature_noise{.scale=700.0f, .octaves=3, .persistence=0.5f, .lacunarity=2.0f};
+    Math::Perlin::Noise<2> m_humidity_noise{.scale=400.0f, .octaves=2, .persistence=0.5f, .lacunarity=2.0f};
+
+    Math::Perlin::Noise<3> m_density_noise{.scale=30.0f, .octaves=2, .persistence=0.7f, .lacunarity=2.0f};
+
+    enum class HillSlice { Mountain, Middle, Valley };
+    enum class LandmassSlice { Land, Beach, Ocean };
+    enum class TemperatureZone { Hot, Fair, Cold };
+    enum class HumidityZone { Wet, Lush, Temperate, Dry };
+    static constexpr uint HillSliceSize = (uint)HillSlice::Valley + 1;
+    static constexpr uint LandmassSliceSize = (uint)LandmassSlice::Ocean + 1;
+    static constexpr uint TemperatureZoneSize = (uint)TemperatureZone::Cold + 1;
+    static constexpr uint HumidityZoneSize = (uint)HumidityZone::Dry + 1;
+
+    static constexpr size_t biome_lookup_table_size = (size_t)HillSliceSize * (size_t)LandmassSliceSize * (size_t)TemperatureZoneSize * (size_t)HumidityZoneSize;
+    static std::array<BiomeType, biome_lookup_table_size> create_biome_lookup_table();
+    static size_t biome_lookup_table_index(HillSlice hill_slice, LandmassSlice landmass_slice, TemperatureZone temperature_zone, HumidityZone humidity_zone);
+    static BiomeType lookup_biome(HillSlice hill_slice, LandmassSlice landmass_slice, TemperatureZone temperature_zone, HumidityZone humidity_zone);
+    static inline std::array<BiomeType, biome_lookup_table_size> biome_lookup_table = create_biome_lookup_table();
 };
 
 }