Added voxel and voxel map definitions

src/main.rs

@@ -1,3 +1,5 @@
+mod voxel;
+
 use std::borrow::Cow;
 use winit::{
     event::{Event, WindowEvent},

src/voxel.rs

@@ -0,0 +1,40 @@
+#[derive(Clone, Copy)]
+struct Voxel {
+    r: u8,
+    g: u8,
+    b: u8
+}
+
+const AIR_VOXEL: Voxel = Voxel { r: 0, g: 0, b: 0 };
+
+struct VoxelMap {
+    data: Vec<Voxel>,
+    width: usize,
+    height: usize,
+    depth: usize
+}
+
+impl VoxelMap {
+    fn new(width: usize, height: usize, depth: usize) -> Self {
+        Self {
+            data: vec![AIR_VOXEL, width * height * depth],
+            width,
+            height,
+            depth
+        }
+    }
+
+    fn set(&mut self, x: usize, y: usize, z: usize, voxel: Voxel) {
+        if x < self.width && y < self.height && z < self.depth {
+            self.data[x + y * self.width + z * self.width * self.height] = voxel;
+        }
+    }
+
+    fn get(&self, x: usize, y: usize, z: usize) -> Voxel {
+        if x < self.width && y < self.height && z < self.depth {
+            self.data[x + y * self.width + z * self.width * self.height]
+        } else {
+            AIR_VOXEL
+        }
+    }
+}