stuff

lib/src/rgb.rs

@@ -0,0 +1,58 @@
+use bytemuck::{cast_slice, Pod, Zeroable};
+use core::{
+    fmt::{self, Debug},
+    ops::Div,
+};
+
+/// An Rgb value that can be safely transmuted to u32 for use with Ws2812.
+#[repr(transparent)]
+#[derive(Clone, Copy, PartialEq, Eq, Pod, Zeroable)]
+pub struct Rgb(u32);
+
+impl Rgb {
+    #[inline(always)]
+    pub const fn new(r: u8, g: u8, b: u8) -> Self {
+        Self(u32::from_be_bytes([g, r, b, 0]))
+    }
+
+    /// Get the red, green, and blue components of this Rgb.
+    #[inline(always)]
+    pub const fn components(&self) -> [u8; 3] {
+        let [g, r, b, _] = self.0.to_be_bytes();
+        [r, g, b]
+    }
+
+    #[inline(always)]
+    pub fn slice_as_u32s(rgbs: &[Rgb]) -> &[u32] {
+        cast_slice(rgbs)
+    }
+}
+
+impl Debug for Rgb {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        let [r, g, b] = self.components();
+        f.debug_tuple("Rgb").field(&r).field(&g).field(&b).finish()
+    }
+}
+
+impl Div<u8> for Rgb {
+    type Output = Rgb;
+
+    fn div(self, d: u8) -> Self::Output {
+        let [r, g, b] = self.components();
+        Rgb::new(r / d, g / d, b / d)
+    }
+}
+
+#[cfg(all(target_arch = "x86_64", test))]
+mod tests {
+    use super::*;
+    use bytemuck::cast;
+
+    #[test]
+    fn test_rgb_as_u32() {
+        let rgb = Rgb::new(0x11, 0x22, 0xCC);
+        let rgb_u32: u32 = cast(rgb);
+        assert_eq!(rgb_u32, 0x2211CC00);
+    }
+}