get palette colours by index

src/palette.rs

@@ -13,7 +13,24 @@ pub struct Palette {
 }
 
 impl Palette {
-    /// todo result
+    /// if trying to get an out-of-bounds index, colours will wrap around
+    /// so if palette has 8 colours (0-7) and index is 8, will return 0
+    pub fn get_colour(&self, index: &u8) -> Option<&Colour> {
+        self.colours.get((index % self.colours.len() as u8) as usize)
+    }
+
+    /// colour 0 is transparent
+    pub fn get_colour_rgba8(&self, index: &u8) -> Vec<u8> {
+        match index {
+            0 => vec![0,0,0,0],
+            _ => {
+                let colour = self.get_colour(index).unwrap();
+                vec![colour.red, colour.green, colour.blue, 255]
+            }
+        }
+    }
+
+    /// todo Result<Palette>
     pub fn from_file(path: PathBuf) -> Self {
         match path.extension().unwrap().to_str().unwrap() {
             "gpl"  => Self::from_gpl(path),