Replace bespoke Generator maps with tensors and matrices

4 files changed, 92 insertions, 61 deletions

diff --git a/src/Math/Matrix.hpp b/src/Math/Matrix.hpp
index 276dc4a..69241d3 100644
--- a/src/Math/Matrix.hpp
+++ b/src/Math/Matrix.hpp
@@ -2,23 +2,21 @@
 
 #include <sstream>
 #include <cstddef>
-#include <iostream>
 #include "Rotation.hpp"
 #include "Trig.hpp"
 
 template <size_t R, size_t C, typename T = float>
 struct Matrix {
-public:
-    Matrix<R, C, T>() : elements{} {};
+    Matrix() : elements{} {};
 
-    Matrix<R, C, T>(T scalar) {
+    explicit Matrix(T scalar) {
         std::fill(elements, elements + R * C, scalar);
     };
 
-    template<typename ...Args, typename std::enable_if<sizeof...(Args) == R * C, int>::type = 0>
-    Matrix<R, C, T>(Args... args): elements{ args... } {};
+    template<typename ...Args, typename std::enable_if_t<sizeof...(Args) == R * C, int> = 0>
+    Matrix(Args... args): elements{ args... } {};
 
-    Matrix<R, C, T>(T values[R * C]) {
+    explicit Matrix(T values[R * C]) {
         std::copy(values, values + R * C, elements);
     };
 
@@ -81,8 +79,8 @@ public:
         return result;
     }
 
-    Matrix<R, C, T> transpose() {
-        Matrix<R, C, T> result{};
+    Matrix transpose() {
+        Matrix result{};
         for (int y = 0; y < R; y++) {
             for (int x = 0; x < C; x++) {
                 result(x, y) = this->operator()(y, x);
@@ -91,16 +89,16 @@ public:
         return result;
     }
 
-    Matrix<R, C, T> operator+(Matrix<R, C, T> other) {
-        Matrix<R, C, T> result{};
+    Matrix operator+(Matrix other) {
+        Matrix result{};
         for (int i = 0; i < R * C; i++) {
             result.elements[i] = elements[i] + other.elements[i];
         }
         return result;
     }
 
-    Matrix<R, C, T> operator*(float scalar) {
-        Matrix<R, C, T> result{};
+    Matrix operator*(float scalar) {
+        Matrix result{};
         for (int i = 0; i < R * C; i++) {
             result.elements[i] = elements[i] * scalar;
         }
diff --git a/src/Math/Tensor.hpp b/src/Math/Tensor.hpp
new file mode 100644
index 0000000..e373c1f
--- /dev/null
+++ b/src/Math/Tensor.hpp
@@ -0,0 +1,43 @@
+#pragma once
+
+template<size_t O, typename T, size_t ...S>
+struct Tensor {
+    static constexpr size_t element_size = (S*...);
+
+    template<typename ...Args>
+    using EnableArgs = std::enable_if_t<sizeof...(Args) == O, bool>;
+    template<typename ...Args>
+    using EnableArgsPerElement = std::enable_if_t<sizeof...(Args) == element_size, bool>;
+    using Enable = std::enable_if_t<sizeof...(S) == O, bool>;
+
+    template<Enable = true>
+    Tensor() : elements{} {}
+
+    template<Enable = true>
+    explicit Tensor(T scalar) {
+        std::fill(elements, elements + element_size, scalar);
+    }
+
+    template<Enable = true, typename ...Args, EnableArgsPerElement<Args...> = true>
+    Tensor(Args... args) : elements{ args... } {}
+
+    template<typename ...Args, EnableArgs<Args...> = true>
+    auto& operator()(Args... args) {
+        return elements[pos(args...)];
+    }
+
+    template<typename ...Args, EnableArgs<Args...> = true>
+    static constexpr size_t pos(Args... args) {
+        size_t positions[O] = {static_cast<size_t>(args)...};
+        size_t dimensions[O] = {S...};
+
+        size_t p = 0;
+        for (int i = 0; i < O; i++) {
+            p *= dimensions[i];
+            p += positions[i];
+        }
+        return p;
+    }
+
+    T elements[element_size];
+};
diff --git a/src/World/Generator.cpp b/src/World/Generator.cpp
index f528278..ada2b7b 100644
--- a/src/World/Generator.cpp
+++ b/src/World/Generator.cpp
@@ -16,62 +16,63 @@ Chunk Generator::generate(int64_t chunk_x, int64_t chunk_y) {
 
     decorate_soil(chunk, biome_map, terrain_map);
 
-    chunk.set_details({{landmass_map.map}, {hill_map.map}, {biome_map.map}});
+    chunk.set_details({{landmass_map}, {hill_map}, {biome_map}});
 
     return chunk;
 }
 
-Generator::ChunkMap2D<float> Generator::generate_landmass_map(int64_t chunk_x, int64_t chunk_y) {
-    ChunkMap2D<float> landmass_map{};
+Generator::Map2D<float> Generator::generate_landmass_map(int64_t chunk_x, int64_t chunk_y) {
+    Matrix<Chunk::Width, Chunk::Width> landmass_map{};
 
     for (uint x = 0; x < Chunk::Width; x++) {
         for (uint y = 0; y < Chunk::Width; y++) {
-            landmass_map.set(x, y, get_landmass(chunk_position_to_world_vector(chunk_x, chunk_y, x, y)));
+            auto world_pos = chunk_position_to_world_vector(chunk_x, chunk_y, x, y);
+            landmass_map(x, y) = get_landmass(world_pos);
         }
     }
 
     return landmass_map;
 }
 
-Generator::ChunkMap2D<float> Generator::generate_hill_map(int64_t chunk_x, int64_t chunk_y) {
-    ChunkMap2D<float> hill_map{};
+Generator::Map2D<float> Generator::generate_hill_map(int64_t chunk_x, int64_t chunk_y) {
+    Map2D<float> hill_map{};
 
     for (uint x = 0; x < Chunk::Width; x++) {
         for (uint y = 0; y < Chunk::Width; y++) {
-            hill_map.set(x, y, get_hill(chunk_position_to_world_vector(chunk_x, chunk_y, x, y)));
+            hill_map(x, y) = get_hill(chunk_position_to_world_vector(chunk_x, chunk_y, x, y));
         }
     }
 
     return hill_map;
 }
 
-Generator::ChunkMap2D<float> Generator::generate_height_map(ChunkMap2D<float>& landmass_map, ChunkMap2D<float>& hill_map, int64_t chunk_x, int64_t chunk_y) {
-    ChunkMap2D<float> height_map{};
+Generator::Map2D<float> Generator::generate_height_map(Map2D<float>& landmass_map, Map2D<float>& hill_map, int64_t chunk_x, int64_t chunk_y) {
+    Map2D<float> height_map{};
 
     for (uint x = 0; x < Chunk::Width; x++) {
         for (uint y = 0; y < Chunk::Width; y++) {
-            auto landmass_effect = landmass_map.get(x, y);
-            auto hill_effect = hill_map.get(x, y);
+            auto landmass_effect = landmass_map(x, y);
+            auto hill_effect = hill_map(x, y);
 
             auto hill = hill_effect * landmass_effect * 1.4 - 0.4;
             auto landmass = landmass_effect * 0.6 + 0.4;
 
             auto height = (hill + landmass) / 2.0f;
 
-            height_map.set(x, y, height);
+            height_map(x, y) = height;
         }
     }
 
     return height_map;
 }
 
-Generator::ChunkMap2D<BiomeType> Generator::generate_biome_map(ChunkMap2D<float>& landmass_map, ChunkMap2D<float>& hill_map, ChunkMap2D<float>& height_map, int64_t chunk_x, int64_t chunk_y) {
-    ChunkMap2D<BiomeType> biome_map{};
+Generator::Map2D<BiomeType> Generator::generate_biome_map(Map2D<float>& landmass_map, Map2D<float>& hill_map, Map2D<float>& height_map, int64_t chunk_x, int64_t chunk_y) {
+    Map2D<BiomeType> biome_map{};
 
     for (uint x = 0; x < Chunk::Width; x++) {
         for (uint y = 0; y < Chunk::Width; y++) {
-            float landmass = landmass_map.get(x, y);
-            float hill = hill_map.get(x, y);
+            float landmass = landmass_map(x, y);
+            float hill = hill_map(x, y);
 
             auto world_pos = chunk_position_to_world_vector(chunk_x, chunk_y, x, y);
             float temperature = get_temperature(world_pos);
@@ -98,27 +99,27 @@ Generator::ChunkMap2D<BiomeType> Generator::generate_biome_map(ChunkMap2D<float>
             else { humidity_zone = HumidityZone::Dry; }
 
             auto biome = lookup_biome(hill_slice, landmass_slice, temparature_zone, humidity_zone);
-            biome_map.set(x, y, biome);
+            biome_map(x, y) = biome;
         }
     }
 
     return biome_map;
 }
 
-Generator::ChunkMap3D<bool> Generator::generate_terrain(ChunkMap2D<float>& height_map, int64_t chunk_x, int64_t chunk_y) {
+Generator::Map3D<bool> Generator::generate_terrain(Map2D<float>& height_map, int64_t chunk_x, int64_t chunk_y) {
     float jaggedness = 0.10f;
 
-    ChunkMap3D<bool> terrain_map{};
+    Map3D<bool> terrain_map{};
     for (uint x = 0; x < Chunk::Width; x++) {
         for (uint z = 0; z < Chunk::Width; z++) {
-            auto height = height_map.get(x, z);
+            auto height = height_map(x, z);
 
             for (uint y = 0; y < Chunk::Height; y++) {
                 float density = get_density({Chunk::Width * chunk_x + (float)x, (float)y, Chunk::Width * chunk_y + (float)z});
                 float threshold = Math::sigmoid(((float)y / (Chunk::Height * height * 2) - 0.5f) / jaggedness);
 
                 if (density > threshold) {
-                    terrain_map.set(x, y, z, true);
+                    terrain_map(x, y, z) = true;
                 }
             }
         }
@@ -127,13 +128,13 @@ Generator::ChunkMap3D<bool> Generator::generate_terrain(ChunkMap2D<float>& heigh
     return terrain_map;
 }
 
-void Generator::decorate_soil(Chunk& chunk, ChunkMap2D<BiomeType>& biome_map, ChunkMap3D<bool>& terrain_map) {
+void Generator::decorate_soil(Chunk& chunk, Map2D<BiomeType>& biome_map, Map3D<bool>& terrain_map) {
     constexpr uint dirt_depth = 4;
     constexpr uint water_height = 39;
 
     for (uint x = 0; x < Chunk::Width; x++) {
         for (uint z = 0; z < Chunk::Width; z++) {
-            auto biome = biome_map.get(x, z);
+            auto biome = biome_map(x, z);
 
             BlockType top_block{};
             BlockType soil_block{};
@@ -159,7 +160,7 @@ void Generator::decorate_soil(Chunk& chunk, ChunkMap2D<BiomeType>& biome_map, Ch
 
             auto column_depth = 0;
             for (uint y = Chunk::Height - 1; y > 0; y--) {
-                auto block = terrain_map.get(x, y, z);
+                auto block = terrain_map(x, y, z);
                 if (block) {
                     if (column_depth == 0 && y >= water_height - 1) {
                         chunk.set(x, y, z, {top_block});
diff --git a/src/World/Generator.hpp b/src/World/Generator.hpp
index 523136a..a90d1bc 100644
--- a/src/World/Generator.hpp
+++ b/src/World/Generator.hpp
@@ -4,6 +4,7 @@
 #include "Chunk.hpp"
 #include "BiomeType.hpp"
 #include "../Math/Perlin.hpp"
+#include "../Math/Tensor.hpp"
 
 namespace MC::World {
 
@@ -12,30 +13,18 @@ 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);
+    template <typename V> using Map2D = Matrix<Chunk::Width, Chunk::Width, V>;
+    template <typename V> using Map3D = Tensor<3, V, Chunk::Width, Chunk::Height, Chunk::Width>;
+
+    Map2D<float> generate_landmass_map(int64_t chunk_x, int64_t chunk_y);
+    Map2D<float> generate_hill_map(int64_t chunk_x, int64_t chunk_y);
+    Map2D<float> generate_height_map(Map2D<float>& landmass_map, Map2D<float>& hill_map, int64_t chunk_x, int64_t chunk_y);
+
+    Map2D<BiomeType> generate_biome_map(Map2D<float>& landmass_map, Map2D<float>& hill_map, Map2D<float>& height_map, int64_t chunk_x, int64_t chunk_y);
+
+    Map3D<bool> generate_terrain(Map2D<float>& height_map, int64_t chunk_x, int64_t chunk_y);
+
+    void decorate_soil(Chunk& chunk, Map2D<BiomeType>& biome_map, Map3D<bool>& terrain_map);
 
     [[nodiscard]] float get_landmass(Vector<2> pos) const;
     [[nodiscard]] float get_hill(Vector<2> pos) const;