Broken Greedy Mesher

cpp-voxel-engine/.vscode/settings.json

@@ -0,0 +1,9 @@
+{
+    "files.associations": {
+        "*.pyx": "python",
+        "*.js": "javascript",
+        "*.c": "c",
+        "*.scene": "yaml",
+        "vector": "cpp"
+    }
+}

cpp-voxel-engine/GreedyMesher.cpp

@@ -1,27 +1,117 @@
 #include "GreedyMesher.h"
+#include <algorithm>
 
-std::vector<Quad> GreedyMesher::mesh(const std::vector<std::vector<std::vector<int>>>& voxelData) {
+// Helper to index into voxels with bounds checking
+inline int voxelAt(const std::vector<std::vector<std::vector<int>>>& v, int x, int y, int z) {
+    if (x<0||y<0||z<0) return 0;
+    if (x>= (int)v.size() || y>= (int)v[0].size() || z>= (int)v[0][0].size()) return 0;
+    return v[x][y][z];
+}
+
+std::vector<Quad> GreedyMesher::mesh(const std::vector<std::vector<std::vector<int>>>& voxels) {
     std::vector<Quad> quads;
+    int sizeX = voxels.size();
+    int sizeY = voxels[0].size();
+    int sizeZ = voxels[0][0].size();
     
-    int sizeX = voxelData.size();
-    if (sizeX == 0) return quads;
-    int sizeY = voxelData[0].size();
-    int sizeZ = voxelData[0][0].size();
-
-    // For simplicity, we create one quad per non-empty voxel.
-    // A complete greedy mesher would merge adjacent quads.
-    for (int x = 0; x < sizeX; ++x) {
-        for (int y = 0; y < sizeY; ++y) {
-            for (int z = 0; z < sizeZ; ++z) {
-                if (voxelData[x][y][z] != 0) {
-                    Quad q;
-                    q.x = (float)x;
-                    q.y = (float)y;
-                    q.z = (float)z;
-                    q.width = 1.0f;
-                    q.height = 1.0f;
-                    q.textureID = voxelData[x][y][z];
-                    quads.push_back(q);
+    // directions: {dx,dy,dz}, and their “du” and “dv” axes
+    static const int dirs[6][3] = {
+        {-1,0,0},{1,0,0},{0,-1,0},{0,1,0},{0,0,-1},{0,0,1}
+    };
+    static const int axisU[6] = {2,2,0,0,0,0}; // u-axis index per face
+    static const int axisV[6] = {1,1,1,1,2,2}; // v-axis index per face
+    
+    // For each face direction
+    for (int d = 0; d < 6; d++) {
+        int dx = dirs[d][0], dy = dirs[d][1], dz = dirs[d][2];
+        int u = axisU[d], v = axisV[d];
+        
+        // dims: dimensions along u,v, and w (the face-normal axis)
+        int dimU = (u==0?sizeX:(u==1?sizeY:sizeZ));
+        int dimV = (v==0?sizeX:(v==1?sizeY:sizeZ));
+        int dimW = (dx!=0?sizeX:(dy!=0?sizeY:sizeZ));
+        
+        // Allocate mask[dimU][dimV]
+        std::vector<int> mask(dimU * dimV, 0);
+        
+        // Sweep along the w axis
+        for (int w = 0; w <= dimW; w++) {
+            // build mask
+            for (int i = 0; i < dimU; i++) {
+                for (int j = 0; j < dimV; j++) {
+                    int x,y,z;
+                    // map (i,j,w) to (x,y,z)
+                    int coord[3];
+                    coord[u] = i;
+                    coord[v] = j;
+                    coord[ (dx!=0?0:(dy!=0?1:2)) ] = w;
+                    x = coord[0]; y = coord[1]; z = coord[2];
+                    int a = voxelAt(voxels, x, y, z);
+                    coord[ (dx!=0?0:(dy!=0?1:2)) ] = w-1;
+                    int b = voxelAt(voxels, coord[0], coord[1], coord[2]);
+                    // if face between a and b should be drawn
+                    if ((a!=0) != (b!=0)) {
+                        // a is solid, b is empty → draw face on b side
+                        mask[i + j*dimU] = (a!=0 ? a : -b);
+                    } else {
+                        mask[i + j*dimU] = 0;
+                    }
+                }
+            }
+            // Greedy merge mask
+            for (int j = 0; j < dimV; j++) {
+                for (int i = 0; i < dimU; ) {
+                    int c = mask[i + j*dimU];
+                    if (c != 0) {
+                        // determine width
+                        int wdt = 1;
+                        while (i+wdt < dimU && mask[i+wdt + j*dimU] == c) wdt++;
+                        // determine height
+                        int hgt = 1;
+                        bool done = false;
+                        while (j+hgt < dimV && !done) {
+                            for (int k = 0; k < wdt; k++) {
+                                if (mask[i+k + (j+hgt)*dimU] != c) {
+                                    done = true;
+                                    break;
+                                }
+                            }
+                            if (!done) hgt++;
+                        }
+                        // emit quad
+                        Quad q;
+                        // base position
+                        float pos[3] = {0,0,0};
+                        pos[0] = pos[1] = pos[2] = 0;
+                        // set w axis coordinate
+                        pos[(dx!=0?0:(dy!=0?1:2))] = w;
+                        // but if this is a “back” face (a was empty, b solid), shift pos back
+                        if (c < 0) pos[(dx!=0?0:(dy!=0?1:2))] = w-1;
+                        // then set u,v
+                        pos[u] = i;
+                        pos[v] = j;
+                        q.x = pos[0];
+                        q.y = pos[1];
+                        q.z = pos[2];
+                        // set du and dv vectors
+                        q.du[0] = q.du[1] = q.du[2] = 0;
+                        q.dv[0] = q.dv[1] = q.dv[2] = 0;
+                        q.du[u] = wdt;
+                        q.dv[v] = hgt;
+                        // normal
+                        q.normal = d;
+                        // textureID
+                        q.textureID = abs(c);
+                        quads.push_back(q);
+                        // zero out mask
+                        for (int jj = 0; jj < hgt; jj++)
+                            for (int ii = 0; ii < wdt; ii++)
+                                mask[i+ii + (j+jj)*dimU] = 0;
+                        // advance
+                        i += wdt;
+                    } else {
+                        i++;
+                    }
                 }
             }
         }

cpp-voxel-engine/GreedyMesher.h

@@ -3,21 +3,25 @@
 
 #include <vector>
 
-// Simple structure to hold a quad (a single face of a voxel block)
+// A single quad face in world space.
 struct Quad {
-    // Starting position of the quad in world space
+    // Position of the minimal corner of the quad
     float x, y, z;
-    // Dimensions of the quad (for this demo we assume unit quads)
-    float width, height;
-    // Texture ID (1 = grass, 2 = dirt, 3 = wood)
+    // Dimensions of the quad along its two axes
+    float du[3], dv[3];
+    // Offset of the second corner: (x+du[0]+dv[0], y+du[1]+dv[1], z+du[2]+dv[2])
+    // Normal direction (0..5) indicates which face this is:
+    // 0 = -X, 1 = +X, 2 = -Y, 3 = +Y, 4 = -Z, 5 = +Z
+    int normal;
+    // Texture ID for this face (block type)
     int textureID;
 };
 
-class GreedyMesher {
-public:
-    // Very basic greedy meshing algorithm:
-    // For demonstration, each non-zero voxel produces a quad.
-    static std::vector<Quad> mesh(const std::vector<std::vector<std::vector<int>>>& voxelData);
-};
+// GreedyMesher namespace
+namespace GreedyMesher {
+    // Given a 3D voxel grid [x][y][z] with integer block IDs (0 = empty),
+    // returns a list of merged Quad faces.
+    std::vector<Quad> mesh(const std::vector<std::vector<std::vector<int>>>& voxels);
+}
 
 #endif // GREEDYMESHER_H

cpp-voxel-engine/Makefile

@@ -1,7 +1,7 @@
 # Compiler settings
 CXX = g++
-CXXFLAGS = -std=c++11 -I. -Iimgui-docking -IC:/msys64/mingw64/include
-LDFLAGS = -LC:/msys64/mingw64/lib -lglfw3 -lopengl32 -lgdi32
+CXXFLAGS = -std=c++20 -I. -Iimgui-docking -IC:/msys64/mingw64/include -DGLEW_STATIC -g
+LDFLAGS = -LC:/msys64/mingw64/lib -lglfw3 -lopengl32 -lgdi32 -lglew32 -lglu32
 
 # List ImGui source files
 IMGUISRCS = imgui-docking/imgui.cpp \

cpp-voxel-engine/VoxelGame.cpp

@@ -1,16 +1,81 @@
+#define STB_IMAGE_IMPLEMENTATION
 #include "VoxelGame.h"
 #include <iostream>
 #include <GL/glew.h>
-
-// Include stb_image implementation (ensure stb_image.h is in your include path)
-#define STB_IMAGE_IMPLEMENTATION
+#include <GL/glu.h>
 #include "stb_image.h"
+#include <cmath>
+#include <unordered_set>
+#include "imgui.h"
+#include "GreedyMesher.h"
+
+namespace {
+    // --- Perlin Noise Helpers ---
+    float fade_(float t) {
+        return t * t * t * (t * (t * 6 - 15) + 10);
+    }
+    float lerp_(float a, float b, float t) {
+        return a + t * (b - a);
+    }
+    float grad_(int hash, float x, float y) {
+        int h = hash & 7;
+        float u = h < 4 ? x : y;
+        float v = h < 4 ? y : x;
+        return ((h & 1) ? -u : u) + ((h & 2) ? -v : v);
+    }
+    float perlin(float x, float y) {
+        static int p[512];
+        static bool init = false;
+        if (!init) {
+            int perm[256] = {
+                151,160,137,91,90,15,131,13,201,95,96,53,194,233,7,225,
+                140,36,103,30,69,142,8,99,37,240,21,10,23,190,6,148,
+                247,120,234,75,0,26,197,62,94,252,219,203,117,35,11,32,
+                57,177,33,88,237,149,56,87,174,20,125,136,171,168,68,175,
+                74,165,71,134,139,48,27,166,77,146,158,231,83,111,229,122,
+                60,211,133,230,220,105,92,41,55,46,245,40,244,102,143,54,
+                65,25,63,161,1,216,80,73,209,76,132,187,208,89,18,169,
+                200,196,135,130,116,188,159,86,164,100,109,198,173,186,3,64,
+                52,217,226,250,124,123,5,202,38,147,118,126,255,82,85,212,
+                207,206,59,227,47,16,58,17,182,189,28,42,223,183,170,213,
+                119,248,152,2,44,154,163,70,221,153,101,155,167,43,172,9,
+                129,22,39,253,19,98,108,110,79,113,224,232,178,185,112,104,
+                218,246,97,228,251,34,242,193,238,210,144,12,191,179,162,241,
+                81,51,145,235,249,14,239,107,49,192,214,31,181,199,106,157,
+                184,84,204,176,115,121,50,45,127,4,150,254,138,236,205,93,
+                222,114,67,29,24,72,243,141,128,195,78,66,215,61,156,180
+            };
+            for (int i = 0; i < 256; i++) {
+                p[i] = perm[i];
+                p[i + 256] = perm[i];
+            }
+            init = true;
+        }
+        int X = int(floor(x)) & 255;
+        int Y = int(floor(y)) & 255;
+        x -= floor(x);
+        y -= floor(y);
+        float u = fade_(x);
+        float v = fade_(y);
+        int A = p[X] + Y, B = p[X + 1] + Y;
+        return lerp_( v,
+            lerp_( u, grad_(p[A],   x,   y), grad_(p[A+1],   x-1,   y) ),
+            lerp_( u, grad_(p[B],   x, y-1), grad_(p[B+1], x-1, y-1) )
+        );
+    }
+}
+
+// Helper to safely query voxel (returns 0 if out of bounds)
+inline int voxelAt(const Chunk& c, int x, int y, int z) {
+    if (x<0||y<0||z<0||x>=16||y>=16||z>=16) return 0;
+    return c.voxels[x][y][z];
+}
+
 
 VoxelGame::VoxelGame()
-    : textureGrass(0), textureDirt(0), textureWood(0)
+    : textureGrass(0), textureDirt(0), textureWood(0),
+      totalChunksLoaded(0), totalChunksEverLoaded(0)
 {
-    // Initialize a 16x16x16 voxel grid with zeros
-    voxelData.resize(16, std::vector<std::vector<int>>(16, std::vector<int>(16, 0)));
 }
 
 VoxelGame::~VoxelGame() {
@@ -19,112 +84,125 @@ VoxelGame::~VoxelGame() {
     glDeleteTextures(1, &textureWood);
 }
 
+
 bool VoxelGame::init() {
-    if (!loadTextures())
-        return false;
-    generateVoxelData();
-    generateMesh();
+    if (!loadTextures()) return false;
+    // Initial camera position
+    float cam[3] = {32,32,80};
+    updateChunks(cam);
+    // Build mesh for each chunk
+    for (auto &p : chunks) {
+        p.second.mesh = GreedyMesher::mesh(p.second.voxels);
+    }
+    glEnable(GL_DEPTH_TEST);
+    glEnable(GL_TEXTURE_2D);
     return true;
 }
 
 bool VoxelGame::loadTextures() {
-    int width, height, nrChannels;
-    unsigned char *data;
-
-    // Load grass texture
-    data = stbi_load("grass.jpg", &width, &height, &nrChannels, 0);
-    if (data) {
-        glGenTextures(1, &textureGrass);
-        glBindTexture(GL_TEXTURE_2D, textureGrass);
-        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
-        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
-        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR);
-        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
-        glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0,
-                     nrChannels == 4 ? GL_RGBA : GL_RGB, GL_UNSIGNED_BYTE, data);
-        glGenerateMipmap(GL_TEXTURE_2D);
-        stbi_image_free(data);
-    } else {
-        std::cerr << "Failed to load grass texture\n";
-        return false;
-    }
-
-    // Load dirt texture
-    data = stbi_load("dirt.jpg", &width, &height, &nrChannels, 0);
-    if (data) {
-        glGenTextures(1, &textureDirt);
-        glBindTexture(GL_TEXTURE_2D, textureDirt);
-        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
-        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
-        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR);
-        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
-        glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0,
-                     nrChannels == 4 ? GL_RGBA : GL_RGB, GL_UNSIGNED_BYTE, data);
-        glGenerateMipmap(GL_TEXTURE_2D);
-        stbi_image_free(data);
-    } else {
-        std::cerr << "Failed to load dirt texture\n";
-        return false;
-    }
-
-    // Load wood texture
-    data = stbi_load("wood.png", &width, &height, &nrChannels, 0);
-    if (data) {
-        glGenTextures(1, &textureWood);
-        glBindTexture(GL_TEXTURE_2D, textureWood);
-        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
-        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
-        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR);
-        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
-        glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0,
-                     nrChannels == 4 ? GL_RGBA : GL_RGB, GL_UNSIGNED_BYTE, data);
-        glGenerateMipmap(GL_TEXTURE_2D);
-        stbi_image_free(data);
-    } else {
-        std::cerr << "Failed to load wood texture\n";
-        return false;
-    }
+    int w,h,n;
+    unsigned char* data;
+    data = stbi_load("grass.jpg",&w,&h,&n,4);
+    if (!data) { std::cerr<<"grass.jpg load fail\n"; return false; }
+    glGenTextures(1,&textureGrass); glBindTexture(GL_TEXTURE_2D,textureGrass);
+    glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_WRAP_S,GL_REPEAT);
+    glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_WRAP_T,GL_REPEAT);
+    glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_LINEAR_MIPMAP_LINEAR);
+    glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_LINEAR);
+    glTexImage2D(GL_TEXTURE_2D,0,GL_RGBA,w,h,0,GL_RGBA,GL_UNSIGNED_BYTE,data);
+    glGenerateMipmap(GL_TEXTURE_2D);
+    stbi_image_free(data);
+    data = stbi_load("dirt.jpg",&w,&h,&n,4);
+    if (!data) { std::cerr<<"dirt.jpg load fail\n"; return false; }
+    glGenTextures(1,&textureDirt); glBindTexture(GL_TEXTURE_2D,textureDirt);
+    glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_WRAP_S,GL_REPEAT);
+    glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_WRAP_T,GL_REPEAT);
+    glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_LINEAR_MIPMAP_LINEAR);
+    glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_LINEAR);
+    glTexImage2D(GL_TEXTURE_2D,0,GL_RGBA,w,h,0,GL_RGBA,GL_UNSIGNED_BYTE,data);
+    glGenerateMipmap(GL_TEXTURE_2D);
+    stbi_image_free(data);
+    data = stbi_load("wood.png",&w,&h,&n,4);
+    if (!data) { std::cerr<<"wood.png load fail\n"; return false; }
+    glGenTextures(1,&textureWood); glBindTexture(GL_TEXTURE_2D,textureWood);
+    glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_WRAP_S,GL_REPEAT);
+    glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_WRAP_T,GL_REPEAT);
+    glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_LINEAR_MIPMAP_LINEAR);
+    glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_LINEAR);
+    glTexImage2D(GL_TEXTURE_2D,0,GL_RGBA,w,h,0,GL_RGBA,GL_UNSIGNED_BYTE,data);
+    glGenerateMipmap(GL_TEXTURE_2D);
+    stbi_image_free(data);
     return true;
 }
 
-void VoxelGame::generateVoxelData() {
-    // For demo purposes:
-    // - Fill the bottom layer with grass (value 1)
-    // - Fill the next layer with dirt (value 2)
-    // - Add a couple of wood blocks (value 3)
-    for (int x = 0; x < 16; ++x) {
-        for (int z = 0; z < 16; ++z) {
-            voxelData[x][0][z] = 1; // grass layer
-            voxelData[x][1][z] = 2; // dirt layer
+Chunk VoxelGame::generateChunk(int cx,int cz) {
+    Chunk c; c.x=cx; c.z=cz;
+    c.voxels.assign(16, std::vector<std::vector<int>>(16, std::vector<int>(16,0)));
+    float scale=0.1f;
+    for(int x=0;x<16;x++)for(int z=0;z<16;z++){
+        float wx = cx*16 + x, wz = cz*16 + z;
+        float n = perlin(wx*scale, wz*scale);
+        int h = int(((n+1)*0.5f)*16);
+        h = std::clamp(h,0,16);
+        for(int y=0;y<h;y++){
+            c.voxels[x][y][z] = (y==h-1?1:2);
         }
     }
-    // Add some wood blocks as an example
-    voxelData[5][2][5] = 3;
-    voxelData[6][2][5] = 3;
+    return c;
 }
 
-void VoxelGame::generateMesh() {
-    // Use the GreedyMesher to create mesh quads from voxel data.
-    meshQuads = GreedyMesher::mesh(voxelData);
+void VoxelGame::updateChunks(const float cam[3]) {
+    int cx = int(floor(cam[0]/16)), cz=int(floor(cam[2]/16));
+    int r=2;
+    std::unordered_set<ChunkKey,ChunkKeyHash> keep;
+    for(int dx=-r;dx<=r;dx++)for(int dz=-r;dz<=r;dz++){
+        ChunkKey key{cx+dx,cz+dz};
+        keep.insert(key);
+        if(chunks.find(key)==chunks.end()){
+            Chunk nc = generateChunk(key.x,key.z);
+            nc.mesh = GreedyMesher::mesh(nc.voxels);
+            chunks[key]=std::move(nc);
+            totalChunksEverLoaded++;
+        }
+    }
+    for(auto it=chunks.begin();it!=chunks.end();){
+        if(!keep.count(it->first)) it=chunks.erase(it);
+        else ++it;
+    }
+    totalChunksLoaded = chunks.size();
 }
 
-void VoxelGame::update(float deltaTime) {
-    // Update game logic (animations, input, physics, etc.)
-    // (This is left minimal for demo purposes)
+void VoxelGame::update(float dt,const float cam[3]){
+    updateChunks(cam);
 }
 
-void VoxelGame::render() {
-    // Here you would typically bind a shader, set uniforms, bind textures,
-    // and render the mesh (e.g. drawing quads as two triangles each).
-    // For this demo, we simply output the number of quads.
-    std::cout << "Rendering " << meshQuads.size() << " quads." << std::endl;
-    // You can extend this function to perform real OpenGL drawing.
+void VoxelGame::render(){
+    for(auto &p:chunks){
+        float ox = p.first.x*16, oz = p.first.z*16;
+        for(auto &q:p.second.mesh){
+            // shift by chunk offset
+            float v0[3]={q.x+ox,q.y,q.z+oz},
+                  v1[3]={q.x+q.du[0]+ox,q.y+q.du[1],q.z+q.du[2]+oz},
+                  v2[3]={q.x+q.du[0]+q.dv[0]+ox,q.y+q.du[1]+q.dv[1],q.z+q.du[2]+q.dv[2]+oz},
+                  v3[3]={q.x+q.dv[0]+ox,q.y+q.dv[1],q.z+q.dv[2]+oz};
+            unsigned int tex = (q.textureID==1?textureGrass:(q.textureID==2?textureDirt:textureWood));
+            glBindTexture(GL_TEXTURE_2D,tex);
+            glBegin(GL_QUADS);
+              glTexCoord2f(0,0); glVertex3fv(v0);
+              glTexCoord2f(1,0); glVertex3fv(v1);
+              glTexCoord2f(1,1); glVertex3fv(v2);
+              glTexCoord2f(0,1); glVertex3fv(v3);
+            glEnd();
+        }
+    }
 }
 
-void VoxelGame::debugUI() {
-    
+void VoxelGame::debugUI(){
     ImGui::Begin("Debug");
-    ImGui::Text("Voxel Game Debug Window");
-    ImGui::Text("Mesh quads count: %d", (int)meshQuads.size());
+    ImGui::Text("Chunks Loaded: %d", totalChunksLoaded);
+    ImGui::Text("Chunks Ever Loaded: %d", totalChunksEverLoaded);
+    static bool wf=false;
+    if(ImGui::Checkbox("Wireframe",&wf))
+        glPolygonMode(GL_FRONT_AND_BACK, wf?GL_LINE:GL_FILL);
     ImGui::End();
 }

cpp-voxel-engine/VoxelGame.h

@@ -2,40 +2,57 @@
 #define VOXELGAME_H
 
 #include <vector>
+
+#include <algorithm>
+#include <unordered_map>
 #include "GreedyMesher.h"
 
+// Structure representing a chunk (16×16×16 voxels)
+struct Chunk {
+    int x, z; // Chunk grid coordinates
+    // 3D voxel data: dimensions [16][16][16]
+    std::vector<std::vector<std::vector<int>>> voxels;
+    // **Merged mesh faces** produced by the greedy mesher
+    std::vector<Quad> mesh;
+};
 
-#include "imgui.h"
-#include "imgui_impl_glfw.h"
-#include "imgui_impl_opengl3.h"
+// A key for identifying a chunk by its grid coordinates.
+struct ChunkKey {
+    int x, z;
+    bool operator==(const ChunkKey &other) const {
+        return x == other.x && z == other.z;
+    }
+};
+
+struct ChunkKeyHash {
+    std::size_t operator()(const ChunkKey &key) const {
+        return std::hash<int>()(key.x) ^ (std::hash<int>()(key.z) << 1);
+    }
+};
 
 class VoxelGame {
 public:
     VoxelGame();
     ~VoxelGame();
-
-    // Initialize textures, voxel data, and mesher
+    
     bool init();
-
-    // Game loop functions
-    void update(float deltaTime);
+    void update(float deltaTime, const float cameraPos[3]);
     void render();
     void debugUI();
-
+    
 private:
-    // 3D voxel data (0 = empty, 1 = grass, 2 = dirt, 3 = wood)
-    std::vector<std::vector<std::vector<int>>> voxelData;
-    // Mesh quads produced by the greedy mesher
-    std::vector<Quad> meshQuads;
-
-    // OpenGL texture IDs for each block type
+    bool loadTextures();
+    Chunk generateChunk(int cx, int cz);
+    void updateChunks(const float cameraPos[3]);
+    void drawCube(float x, float y, float z, int voxelType);
+    
+    std::unordered_map<ChunkKey, Chunk, ChunkKeyHash> chunks;
+    int totalChunksLoaded;
+    int totalChunksEverLoaded;
+    
     unsigned int textureGrass;
     unsigned int textureDirt;
     unsigned int textureWood;
-
-    bool loadTextures();
-    void generateVoxelData();
-    void generateMesh();
 };
 
 #endif // VOXELGAME_H

cpp-voxel-engine/imgui.ini

@@ -0,0 +1,10 @@
+[Window][Debug##Default]
+Pos=60,60
+Size=400,400
+Collapsed=0
+
+[Window][Debug]
+Pos=492,48
+Size=214,119
+Collapsed=0
+

cpp-voxel-engine/main.cpp

@@ -1,24 +1,67 @@
 #include <iostream>
+#include <cmath>
 #include <GL/glew.h>
 #include <GLFW/glfw3.h>
-#include "VoxelGame.h"
-
-// ImGui headers (make sure these files are available in your include path)
+#include <GL/glu.h>
 #include "imgui.h"
+#include "imgui_internal.h"  // For Im_PI
 #include "imgui_impl_glfw.h"
 #include "imgui_impl_opengl3.h"
+#include "VoxelGame.h"
+
+// Global camera variables.
+float yaw = -90.0f;
+float pitch = 0.0f;
+float lastX = 400.0f, lastY = 300.0f;
+bool firstMouse = true;
+float cameraPos[3] = {32.0f, 32.0f, 80.0f};
+float cameraFront[3] = {0.0f, 0.0f, -1.0f};
+float cameraUp[3] = {0.0f, 1.0f, 0.0f};
+
+void mouse_callback(GLFWwindow* window, double xpos, double ypos) {
+    if (glfwGetInputMode(window, GLFW_CURSOR) == GLFW_CURSOR_NORMAL)
+        return;
+    if (firstMouse) {
+        lastX = static_cast<float>(xpos);
+        lastY = static_cast<float>(ypos);
+        firstMouse = false;
+    }
+    float xoffset = static_cast<float>(xpos) - lastX;
+    float yoffset = lastY - static_cast<float>(ypos);
+    lastX = static_cast<float>(xpos);
+    lastY = static_cast<float>(ypos);
+    
+    float sensitivity = 0.1f;
+    xoffset *= sensitivity;
+    yoffset *= sensitivity;
+    
+    yaw += xoffset;
+    pitch += yoffset;
+    if (pitch > 89.0f) pitch = 89.0f;
+    if (pitch < -89.0f) pitch = -89.0f;
+    
+    float radYaw = yaw * static_cast<float>(IM_PI) / 180.0f;
+    float radPitch = pitch * static_cast<float>(IM_PI) / 180.0f;
+    
+    cameraFront[0] = cos(radYaw) * cos(radPitch);
+    cameraFront[1] = sin(radPitch);
+    cameraFront[2] = sin(radYaw) * cos(radPitch);
+    float len = std::sqrt(cameraFront[0]*cameraFront[0] +
+                          cameraFront[1]*cameraFront[1] +
+                          cameraFront[2]*cameraFront[2]);
+    cameraFront[0] /= len;
+    cameraFront[1] /= len;
+    cameraFront[2] /= len;
+}
 
-// Initialize GLFW and create a window
 GLFWwindow* initWindow(int width, int height, const char* title) {
     if (!glfwInit()) {
         std::cerr << "Failed to initialize GLFW\n";
         return nullptr;
     }
-    // Request OpenGL 3.3 Core Profile
     glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
     glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
-    glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);
-
+    glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_COMPAT_PROFILE);
     GLFWwindow* window = glfwCreateWindow(width, height, title, nullptr, nullptr);
     if (!window) {
         std::cerr << "Failed to create GLFW window\n";
@@ -26,8 +69,14 @@ GLFWwindow* initWindow(int width, int height, const char* title) {
         return nullptr;
     }
     glfwMakeContextCurrent(window);
-
+    glfwSetCursorPosCallback(window, mouse_callback);
+    glfwSetInputMode(window, GLFW_CURSOR, GLFW_CURSOR_DISABLED);
     
+    glewExperimental = GL_TRUE;
+    if (glewInit() != GLEW_OK) {
+        std::cerr << "GLEW Error\n";
+        return nullptr;
+    }
     return window;
 }
 
@@ -35,59 +84,110 @@ int main() {
     GLFWwindow* window = initWindow(800, 600, "Voxel Game");
     if (!window)
         return -1;
-
-    // Setup ImGui context
+    
     IMGUI_CHECKVERSION();
     ImGui::CreateContext();
-    ImGuiIO &io = ImGui::GetIO();
-    (void)io;
+    ImGuiIO &io = ImGui::GetIO(); (void)io;
     ImGui::StyleColorsDark();
     ImGui_ImplGlfw_InitForOpenGL(window, true);
     ImGui_ImplOpenGL3_Init("#version 330");
-
-    // Create game instance and initialize it
+    
     VoxelGame game;
     if (!game.init()) {
         std::cerr << "Failed to initialize game\n";
         return -1;
     }
-
-    // Main loop
+    
+    float deltaTime = 0.0f, lastFrame = 0.0f;
+    static bool cursorEnabled = false;
+    static bool f1Pressed = false;
+    
     while (!glfwWindowShouldClose(window)) {
+        float currentFrame = static_cast<float>(glfwGetTime());
+        deltaTime = currentFrame - lastFrame;
+        lastFrame = currentFrame;
         glfwPollEvents();
-
-        // Update game logic (assume fixed deltaTime for demo)
-        game.update(0.016f);
-
-        // Start new ImGui frame
+        
+        // Toggle cursor lock with F1 (if ImGui isn’t capturing the mouse).
+        if (glfwGetKey(window, GLFW_KEY_F1) == GLFW_PRESS && !ImGui::GetIO().WantCaptureMouse) {
+            if (!f1Pressed) {
+                cursorEnabled = !cursorEnabled;
+                glfwSetInputMode(window, GLFW_CURSOR, cursorEnabled ? GLFW_CURSOR_NORMAL : GLFW_CURSOR_DISABLED);
+                f1Pressed = true;
+                firstMouse = true;
+            }
+        } else if (glfwGetKey(window, GLFW_KEY_F1) == GLFW_RELEASE) {
+            f1Pressed = false;
+        }
+        
+        float cameraSpeed = 5.0f * deltaTime;
+        if (glfwGetKey(window, GLFW_KEY_W) == GLFW_PRESS) {
+            cameraPos[0] += cameraFront[0] * cameraSpeed;
+            cameraPos[1] += cameraFront[1] * cameraSpeed;
+            cameraPos[2] += cameraFront[2] * cameraSpeed;
+        }
+        if (glfwGetKey(window, GLFW_KEY_S) == GLFW_PRESS) {
+            cameraPos[0] -= cameraFront[0] * cameraSpeed;
+            cameraPos[1] -= cameraFront[1] * cameraSpeed;
+            cameraPos[2] -= cameraFront[2] * cameraSpeed;
+        }
+        if (glfwGetKey(window, GLFW_KEY_A) == GLFW_PRESS) {
+            float right[3] = {
+                cameraFront[1]*cameraUp[2] - cameraFront[2]*cameraUp[1],
+                cameraFront[2]*cameraUp[0] - cameraFront[0]*cameraUp[2],
+                cameraFront[0]*cameraUp[1] - cameraFront[1]*cameraUp[0]
+            };
+            float rLen = std::sqrt(right[0]*right[0] + right[1]*right[1] + right[2]*right[2]);
+            right[0] /= rLen; right[1] /= rLen; right[2] /= rLen;
+            cameraPos[0] -= right[0] * cameraSpeed;
+            cameraPos[1] -= right[1] * cameraSpeed;
+            cameraPos[2] -= right[2] * cameraSpeed;
+        }
+        if (glfwGetKey(window, GLFW_KEY_D) == GLFW_PRESS) {
+            float right[3] = {
+                cameraFront[1]*cameraUp[2] - cameraFront[2]*cameraUp[1],
+                cameraFront[2]*cameraUp[0] - cameraFront[0]*cameraUp[2],
+                cameraFront[0]*cameraUp[1] - cameraFront[1]*cameraUp[0]
+            };
+            float rLen = std::sqrt(right[0]*right[0] + right[1]*right[1] + right[2]*right[2]);
+            right[0] /= rLen; right[1] /= rLen; right[2] /= rLen;
+            cameraPos[0] += right[0] * cameraSpeed;
+            cameraPos[1] += right[1] * cameraSpeed;
+            cameraPos[2] += right[2] * cameraSpeed;
+        }
+        
         ImGui_ImplOpenGL3_NewFrame();
         ImGui_ImplGlfw_NewFrame();
         ImGui::NewFrame();
-
-        // Draw debug UI from game
-        game.debugUI();
-
-        ImGui::Render();
-
-        // Clear the screen
-        glClearColor(0.2f, 0.3f, 0.3f, 1.0f);
-        glClear(GL_COLOR_BUFFER_BIT);
-
-        // Render the voxel game (mesh drawing, etc.)
+        
+        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+        
+        glMatrixMode(GL_PROJECTION);
+        glLoadIdentity();
+        gluPerspective(45.0, 800.0/600.0, 0.1, 200.0);
+        
+        glMatrixMode(GL_MODELVIEW);
+        glLoadIdentity();
+        float centerX = cameraPos[0] + cameraFront[0];
+        float centerY = cameraPos[1] + cameraFront[1];
+        float centerZ = cameraPos[2] + cameraFront[2];
+        gluLookAt(cameraPos[0], cameraPos[1], cameraPos[2],
+                  centerX, centerY, centerZ,
+                  cameraUp[0], cameraUp[1], cameraUp[2]);
+        
+        game.update(deltaTime, cameraPos);
         game.render();
-
-        // Render ImGui on top
+        game.debugUI();
+        
+        ImGui::Render();
         ImGui_ImplOpenGL3_RenderDrawData(ImGui::GetDrawData());
-
         glfwSwapBuffers(window);
     }
-
-    // Cleanup ImGui and GLFW
+    
     ImGui_ImplOpenGL3_Shutdown();
     ImGui_ImplGlfw_Shutdown();
     ImGui::DestroyContext();
     glfwDestroyWindow(window);
     glfwTerminate();
-
     return 0;
 }