voxel example

src/3d/VoxelGrid.h

@@ -0,0 +1,121 @@
+// VoxelGrid.h - Dense 3D voxel array with material palette
+// Part of McRogueFace 3D Extension - Milestones 9-10
+#pragma once
+
+#include "../Common.h"
+#include "Math3D.h"
+#include "MeshLayer.h"  // For MeshVertex (needed for std::vector<MeshVertex>)
+#include <vector>
+#include <string>
+#include <stdexcept>
+
+namespace mcrf {
+
+// =============================================================================
+// VoxelMaterial - Properties for a voxel material type
+// =============================================================================
+
+struct VoxelMaterial {
+    std::string name;
+    sf::Color color;           // Fallback solid color
+    int spriteIndex = -1;      // Texture atlas index (-1 = use color)
+    bool transparent = false;  // For FOV projection and face culling
+    float pathCost = 1.0f;     // Navigation cost multiplier (0 = impassable)
+
+    VoxelMaterial() : name("unnamed"), color(sf::Color::White) {}
+    VoxelMaterial(const std::string& n, sf::Color c, int sprite = -1,
+                  bool transp = false, float cost = 1.0f)
+        : name(n), color(c), spriteIndex(sprite), transparent(transp), pathCost(cost) {}
+};
+
+// =============================================================================
+// VoxelGrid - Dense 3D array of material IDs
+// =============================================================================
+
+class VoxelGrid {
+private:
+    int width_, height_, depth_;
+    float cellSize_;
+    std::vector<uint8_t> data_;          // Material ID per cell (0 = air)
+    std::vector<VoxelMaterial> materials_;
+
+    // Transform
+    vec3 offset_;
+    float rotation_ = 0.0f;  // Y-axis only, degrees
+
+    // Mesh caching (Milestone 10)
+    mutable bool meshDirty_ = true;
+    mutable std::vector<MeshVertex> cachedVertices_;
+
+    // Index calculation (row-major: X varies fastest, then Y, then Z)
+    inline size_t index(int x, int y, int z) const {
+        return static_cast<size_t>(z) * (width_ * height_) +
+               static_cast<size_t>(y) * width_ +
+               static_cast<size_t>(x);
+    }
+
+public:
+    // Constructor
+    VoxelGrid(int w, int h, int d, float cellSize = 1.0f);
+
+    // Dimensions (read-only)
+    int width() const { return width_; }
+    int height() const { return height_; }
+    int depth() const { return depth_; }
+    float cellSize() const { return cellSize_; }
+    size_t totalVoxels() const { return static_cast<size_t>(width_) * height_ * depth_; }
+
+    // Per-voxel access
+    uint8_t get(int x, int y, int z) const;
+    void set(int x, int y, int z, uint8_t material);
+    bool isValid(int x, int y, int z) const;
+
+    // Material palette
+    // Returns 1-indexed material ID (0 = air, always implicit)
+    uint8_t addMaterial(const VoxelMaterial& mat);
+    uint8_t addMaterial(const std::string& name, sf::Color color,
+                        int spriteIndex = -1, bool transparent = false,
+                        float pathCost = 1.0f);
+    const VoxelMaterial& getMaterial(uint8_t id) const;
+    size_t materialCount() const { return materials_.size(); }
+
+    // Bulk operations
+    void fill(uint8_t material);
+    void clear() { fill(0); }
+    void fillBox(int x0, int y0, int z0, int x1, int y1, int z1, uint8_t material);
+
+    // Transform
+    void setOffset(const vec3& offset) { offset_ = offset; }
+    void setOffset(float x, float y, float z) { offset_ = vec3(x, y, z); }
+    vec3 getOffset() const { return offset_; }
+    void setRotation(float degrees) { rotation_ = degrees; }
+    float getRotation() const { return rotation_; }
+    mat4 getModelMatrix() const;
+
+    // Statistics
+    size_t countNonAir() const;
+    size_t countMaterial(uint8_t material) const;
+
+    // Mesh caching (Milestone 10)
+    /// Mark mesh as needing rebuild (called automatically by set/fill operations)
+    void markDirty() { meshDirty_ = true; }
+
+    /// Check if mesh needs rebuild
+    bool isMeshDirty() const { return meshDirty_; }
+
+    /// Get vertices for rendering (rebuilds mesh if dirty)
+    const std::vector<MeshVertex>& getVertices() const;
+
+    /// Force immediate mesh rebuild
+    void rebuildMesh() const;
+
+    /// Get vertex count after mesh generation
+    size_t vertexCount() const { return cachedVertices_.size(); }
+
+    // Memory info (for debugging)
+    size_t memoryUsageBytes() const {
+        return data_.size() + materials_.size() * sizeof(VoxelMaterial);
+    }
+};
+
+} // namespace mcrf