allocating array on heap

src/renderer/buffers/brick_buffer.rs

@@ -1,10 +1,39 @@
 
+use std::convert::TryInto;
+
 const BRICK_SIZE : usize = 32; // 32x32x32 brick size
 const BRICK_NUM : usize = 64; // 64 bricks in texture
 
+const BRICK_LEN : usize = BRICK_SIZE*BRICK_SIZE*BRICK_SIZE;
+const DATA_LEN : usize = BRICK_LEN * BRICK_NUM;
+
+struct BrickData {
+    data: Box<[u8]>
+}
+
+impl BrickData {
+
+    pub fn new() -> Self {
+        let data = vec![0_u8; DATA_LEN].into_boxed_slice();
+        Self { data }
+    }
+
+    pub fn set(&mut self, brick: usize, x: usize, y: usize, z: usize, value: u8)
+    {
+        let local_idx = x + BRICK_SIZE * (y + BRICK_SIZE * z);
+        let offset = brick * BRICK_LEN;
+        self.data[offset + local_idx] = value;
+    }
+
+    pub fn get_1024(&mut self, offset: usize) -> [u8; 1024]
+    {
+        self.data[offset..offset+1024].try_into().expect("wrong size")
+    }
+}
+
 
 pub struct BrickBuffer {
-    //bricks: [[u8; BRICK_SIZE*BRICK_SIZE*BRICK_SIZE];BRICK_NUM],
+    bricks: BrickData,
     texture: wgpu::Texture,
     size: wgpu::Extent3d,
     pub bind_layout: wgpu::BindGroupLayout,
@@ -68,17 +97,16 @@ impl BrickBuffer {
         );
 
         // Data
-        // let mut bricks = [[0; BRICK_SIZE*BRICK_SIZE*BRICK_SIZE]; BRICK_NUM];
+        let mut bricks = BrickData::new();
-        // for x in 0..32 {
+        for x in 0..32 {
-        //     for y in 0..16 {
+            for y in 0..16 {
-        //         for z in 0..32 {
+                for z in 0..32 {
-        //             let idx = x + BRICK_SIZE * (y + BRICK_SIZE * z);
+                    bricks.set(0, x, y, z, 1);
-        //             bricks[0][idx] = 1;
+                }
-        //         }
+            }
-        //     }
+        }
-        // }
 
         // Done
-        Self { texture, size, bind_layout, bind_group }
+        Self { bricks, texture, size, bind_layout, bind_group }
     }
 }