Moved node buffer logic to Nodes struct

src/renderer/buffers/nodes.rs

@@ -0,0 +1,63 @@
+use byteorder::{LittleEndian, ByteOrder};
+
+pub const NODE_TEX_SIZE: usize = 128; // 32x32x32 nodes in texture
+pub const NODE_TEX_SIZE_SQ: usize = NODE_TEX_SIZE*NODE_TEX_SIZE;
+pub const NODE_TEX_SIZE_QB: usize = NODE_TEX_SIZE*NODE_TEX_SIZE*NODE_TEX_SIZE;
+
+
+pub struct Nodes {
+    node_buffer_a: Box<[u32]>,
+    node_buffer_b: Box<[u32]>,
+    active_buffer: u8,
+    modified: bool
+}
+
+impl Nodes {
+    pub fn new() -> Self {
+        Self {
+            node_buffer_a: vec![0_u32; NODE_TEX_SIZE_QB].into_boxed_slice(),
+            node_buffer_b: vec![0_u32; NODE_TEX_SIZE_QB].into_boxed_slice(),
+            active_buffer: 0,
+            modified: false
+        }
+    }
+
+    pub fn get_node(&self, index: usize) -> u32 {
+        if self.active_buffer == 0 { self.node_buffer_a[index] }
+        else { self.node_buffer_b[index] }
+    }
+
+    pub fn set_node(&mut self, index: usize, value: u32) {
+        if self.active_buffer == 0 { self.node_buffer_a[index] = value; }
+        else { self.node_buffer_b[index] = value; }
+        self.modified = true;
+    }
+
+    pub fn update(&mut self, queue: &wgpu::Queue, texture: &wgpu::Texture) {
+        if self.modified {
+            self.modified = false;
+            
+            // Select target node buffer
+            let node_buffer;
+            if self.active_buffer == 0 { node_buffer = &self.node_buffer_a; }
+            else { node_buffer = &self.node_buffer_b; }
+
+            // Write all nodes to gpu
+            for z in 0..NODE_TEX_SIZE {
+
+                // Convert u32 node buffer to u8
+                let node_origin = wgpu::Origin3d{ x:0, y: 0, z: z as u32 };
+                let node_size = wgpu::Extent3d { width: NODE_TEX_SIZE as u32, height: NODE_TEX_SIZE as u32, depth: 1 };
+                let mut node_bytes = [0_u8; NODE_TEX_SIZE_SQ*4];
+                let offset = NODE_TEX_SIZE_SQ*z;
+                LittleEndian::write_u32_into(&node_buffer[offset..offset+NODE_TEX_SIZE_SQ], &mut node_bytes);
+        
+                // Write nodes
+                queue.write_texture(
+                    wgpu::TextureCopyView { texture: texture, mip_level: 0, origin: node_origin }, &node_bytes,
+                    wgpu::TextureDataLayout { offset: 0, bytes_per_row: 4*node_size.width, rows_per_image: node_size.height }, node_size
+                );
+            }
+        }
+    }
+}