perf: optimize multi-chunk rendering logic

src/gameplay/chunk.cpp

@@ -0,0 +1,83 @@
+#include <Cubed/gameplay/chunk.hpp>
+#include <Cubed/gameplay/world.hpp>
+Chunk::Chunk(World& world, ChunkPos chunk_pos) : 
+    m_world(world),
+    m_chunk_pos(chunk_pos)     
+{
+
+}
+
+Chunk::~Chunk() {
+
+}
+
+const std::vector<uint8_t>& Chunk::get_chunk_blocks() const{
+    return m_blocks;
+}
+
+
+int Chunk::get_index(int x, int y, int z) {
+    return x * CHUCK_SIZE * CHUCK_SIZE + y * CHUCK_SIZE + z;
+}
+
+void Chunk::gen_vertex_data() {
+    for (int x = 0; x < CHUCK_SIZE; x++) {
+        for (int z = 0; z < CHUCK_SIZE; z++) {
+            for (int y = 0; y < CHUCK_SIZE; y++) {
+                int world_x = x + m_chunk_pos.x * CHUCK_SIZE;
+                int world_z = z + m_chunk_pos.z * CHUCK_SIZE;
+                int world_y = y;
+                const auto& block_render_data = m_world.get_block_render_data(world_x, world_y, world_z);
+                // air
+                if (block_render_data.block_id == 0) {
+                    continue;
+                }
+                for (int face = 0; face < 6; face++) {
+                    if (!block_render_data.draw_face[face]) {
+                        continue;
+                    }
+                    for (int i = 0; i < 6; i++) {
+                        Vertex vex = {
+                            VERTICES_POS[face][i][0] + (float)world_x * 1.0f,
+                            VERTICES_POS[face][i][1] + (float)world_y * 1.0f,
+                            VERTICES_POS[face][i][2] + (float)world_z * 1.0f,
+                            TEX_COORDS[face][i][0],
+                            TEX_COORDS[face][i][1],
+                            static_cast<float>(block_render_data.block_id * 6 + face) 
+
+                        };
+                        m_vertexs_data.emplace_back(vex);
+                    }    
+                }
+            }
+            
+        }
+    }
+}
+
+GLuint Chunk::get_vbo() const{
+    return m_vbo;
+}
+
+const std::vector<Vertex>& Chunk::get_vertex_data() const{
+    return m_vertexs_data;
+}
+
+void Chunk::init_chunk() {
+    m_blocks.assign(CHUCK_SIZE * CHUCK_SIZE * CHUCK_SIZE, 0);
+    for (int x = 0; x < CHUCK_SIZE; x++) {
+        for (int y = 0; y < 2; y++) {
+            for (int z = 0; z < CHUCK_SIZE; z++) {
+                m_blocks[get_index(x, y, z)] = 1;
+            }
+        }
+    }
+    gen_vertex_data();
+    
+    glGenBuffers(1, &m_vbo);
+    glBindBuffer(GL_ARRAY_BUFFER, m_vbo);
+    glBufferData(GL_ARRAY_BUFFER, m_vertexs_data.size() * sizeof(Vertex), m_vertexs_data.data(), GL_STATIC_DRAW);
+    glBindBuffer(GL_ARRAY_BUFFER, 0);
+}
+
+