update readme and remove a debug

README.md

@@ -47,3 +47,9 @@ It took me a couple of days to fix the ray casting. I forgot that my mesh is off
 Woah! The camera doesn't just phase through placed blocks anymore! The camera can also fall into the void for eternity! So cool!
 
 ![The camera, sitting atop a built platform, overlooking another "Hi" built from stone](.attachments/physics.png)
+
+## 0.8.0 : Data Structure Redo - 11/19/25
+
+Final part of the blog post tutorial. Changing the data structure of the Chunk's to store voxels in a 1d array instead of a HashMap.
+
+![Hi written on a dirt plane in stone.](.attachments/data-structure-redo.png)

src/Chunk.h

@@ -59,25 +59,33 @@ class Chunk {
     // 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 {
-        return std::all_of(data.begin(), data.end(), [](VoxelKind k){
+        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 + 1> data;
+    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);