voxel-engine/src/Chunk.h

96 lines
2.4 KiB
C++

#ifndef CHUNK_H
#define CHUNK_H
#include <cstdint>
#include <unordered_map>
#include <memory>
#include <array>
#include <algorithm>
#include <iostream>
#include <glm/glm.hpp>
#include "Mesh.h"
enum class VoxelKind : uint8_t {
Air,
Dirt,
Stone
};
const int CHUNK_SIZE = 32;
// Hash function for glm::ivec3 to use with unordered_set
// Still used in World.h
namespace std {
template <>
struct hash<glm::ivec3> {
size_t operator()(const glm::ivec3& v) const {
// Combine hash values of x, y, z components
size_t h1 = hash<int>()(v.x);
size_t h2 = hash<int>()(v.y);
size_t h3 = hash<int>()(v.z);
// Use a simple hash combination algorithm
return h1 ^ (h2 << 1) ^ (h3 << 2);
}
};
}
class Chunk {
public:
Chunk();
Mesh* getMesh(); // Returns pointer, can be null if not generated yet
void generateMesh();
void regenerateMesh();
// Accessors
inline VoxelKind get(int x, int y, int z) const {
return data[index(x, y, z)];
}
inline VoxelKind get(glm::ivec3 pos) const {
// std::cout << "Getting Pos (" << pos.x << ", " << pos.y << ", " << pos.z << ")" << std::endl;
return data[index(pos.x, pos.y, pos.z)];
}
// Mutators
inline void set(int x, int y, int z, VoxelKind v) {
data[index(x, y, z)] = v;
empty_checked = false; // Invalidate cache
}
inline void set(glm::ivec3 pos, VoxelKind v) {
// std::cout << "Setting Pos (" << pos.x << ", " << pos.y << ", " << pos.z << ")" << std::endl;
data[index(pos.x, pos.y, pos.z)] = v;
empty_checked = false; // Invalidate cache
}
// Other
inline bool isEmpty() const {
if (!empty_checked) {
is_empty = std::all_of(data.begin(), data.end(), [](VoxelKind k){
return k == VoxelKind::Air;
});
empty_checked = true;
}
return is_empty;
}
private:
static constexpr int SIZE = CHUNK_SIZE;
static constexpr int TOTAL = SIZE * SIZE * SIZE;
std::array<VoxelKind, TOTAL> data;
std::unique_ptr<Mesh> mesh; // Nullable mesh
mutable bool is_empty = true; // Cache empty state
mutable bool empty_checked = false; // Track if we've checked
static inline constexpr int index(int x, int y, int z) noexcept {
return x + (y * SIZE) + (z * SIZE * SIZE);
}
};
#endif // CHUNK_H