use core::fmt;
#[derive(Copy, Clone)]
#[repr(transparent)]
pub struct Color {
pub data: u32,
}
impl Color {
pub const fn rgb(r: u8, g: u8, b: u8) -> Self {
Color {
#[cfg(not(target_arch = "wasm32"))]
data: 0xFF000000 | ((r as u32) << 16) | ((g as u32) << 8) | (b as u32),
#[cfg(target_arch = "wasm32")]
data: 0xFF000000 | ((b as u32) << 16) | ((g as u32) << 8) | (r as u32),
}
}
pub const fn rgba(r: u8, g: u8, b: u8, a: u8) -> Self {
Color {
#[cfg(not(target_arch = "wasm32"))]
data: ((a as u32) << 24) | ((r as u32) << 16) | ((g as u32) << 8) | (b as u32),
#[cfg(target_arch = "wasm32")]
data: ((a as u32) << 24) | ((b as u32) << 16) | ((g as u32) << 8) | (r as u32),
}
}
#[cfg(not(target_arch = "wasm32"))]
pub fn r(&self) -> u8 {
((self.data & 0x00FF0000) >> 16) as u8
}
#[cfg(target_arch = "wasm32")]
pub fn r(&self) -> u8 {
(self.data & 0x000000FF) as u8
}
pub fn g(&self) -> u8 {
((self.data & 0x0000FF00) >> 8) as u8
}
#[cfg(not(target_arch = "wasm32"))]
pub fn b(&self) -> u8 {
(self.data & 0x000000FF) as u8
}
#[cfg(target_arch = "wasm32")]
pub fn b(&self) -> u8 {
((self.data & 0x00FF0000) >> 16) as u8
}
pub fn a(&self) -> u8 {
((self.data & 0xFF000000) >> 24) as u8
}
pub fn interpolate(start_color: Color, end_color: Color, scale: f64) -> Color {
let r = Color::interp(start_color.r(), end_color.r(), scale);
let g = Color::interp(start_color.g(), end_color.g(), scale);
let b = Color::interp(start_color.b(), end_color.b(), scale);
let a = Color::interp(start_color.a(), end_color.a(), scale);
Color::rgba(r, g, b, a)
}
fn interp(start_color: u8, end_color: u8, scale: f64) -> u8 {
((end_color as f64 - start_color as f64) * scale + start_color as f64) as u8
}
}
impl PartialEq for Color {
fn eq(&self, other: &Color) -> bool {
self.r() == other.r() && self.g() == other.g() && self.b() == other.b()
}
}
impl fmt::Debug for Color {
fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
write!(f, "{:#010X}", { self.data })
}
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn partial_eq() {
assert_eq!(Color::rgb(1, 2, 3), Color::rgba(1, 2, 3, 200));
assert_ne!(Color::rgb(1, 2, 3), Color::rgba(11, 2, 3, 200));
assert_eq!(Color::rgba(1, 2, 3, 200), Color::rgba(1, 2, 3, 200));
}
#[test]
fn alignment() {
assert_eq!(4, core::mem::size_of::<Color>());
assert_eq!(8, core::mem::size_of::<[Color; 2]>());
assert_eq!(12, core::mem::size_of::<[Color; 3]>());
assert_eq!(16, core::mem::size_of::<[Color; 4]>());
assert_eq!(20, core::mem::size_of::<[Color; 5]>());
}
}