Files
dashboard/src/trekstor/rgba.rs
2026-08-07 14:27:58 +02:00

126 lines
3.1 KiB
Rust

use embedded_graphics_core::pixelcolor::*;
use linfb::shape::Color;
use slint::platform::software_renderer::TargetPixel;
/// Simple RGBA color wrapper.
#[derive(Clone, Copy, Debug, PartialEq, Eq)]
pub struct Rgba<C: RgbColor>(C, u8);
#[allow(unused)]
#[inline(always)]
fn mul_blend_u8(delta: u32, a: u32) -> u32 {
// Exact (delta * a) / 255 using the div255 trick (no slow integer division).
// Valid for 0..=65535 inputs; see Hacker's Delight 10-16.
let t = delta * a + 128;
(t + (t >> 8)) >> 8
}
#[allow(unused)]
impl<C: RgbColor> Rgba<C> {
/// Create a new RGBA color.
pub const fn new(color: C, alpha: u8) -> Self {
Self(color, alpha)
}
/// Get the color component.
pub const fn rgb(&self) -> C {
self.0
}
pub fn r(&self) -> u8 {
self.0.r()
}
pub fn g(&self) -> u8 {
self.0.g()
}
pub fn b(&self) -> u8 {
self.0.b()
}
/// Get the alpha component (0..=255).
pub const fn a(&self) -> u8 {
self.1
}
}
impl<C: RgbColor> PixelColor for Rgba<C> {
type Raw = C::Raw;
}
#[allow(unused)]
pub trait Blend<T> {
fn blend(&self, bg: T) -> T;
}
impl Blend<Rgb888> for Rgba<Rgb888> {
#[inline(always)]
fn blend(&self, bg: Rgb888) -> Rgb888 {
let a = self.a() as u32;
if a == 0 {
return bg;
}
if a == 255 {
return self.rgb();
}
let fr = self.rgb().r() as u32;
let fg = self.rgb().g() as u32;
let fb = self.rgb().b() as u32;
let br = bg.r() as u32;
let bgc = bg.g() as u32;
let bb = bg.b() as u32;
let r = (br + mul_blend_u8(fr.wrapping_sub(br), a)) as u8;
let g = (bgc + mul_blend_u8(fg.wrapping_sub(bgc), a)) as u8;
let b = (bb + mul_blend_u8(fb.wrapping_sub(bb), a)) as u8;
Rgb888::new(r, g, b)
}
}
impl TargetPixel for Rgba<Rgb888> {
fn blend(&mut self, color: slint::platform::software_renderer::PremultipliedRgbaColor) {
let a = self.a() as u32;
// if a == 0 {
// return bg;
// }
// if a == 255 {
// return self.rgb();
// }
let fr = self.rgb().r() as u32;
let fg = self.rgb().g() as u32;
let fb = self.rgb().b() as u32;
let br = color.red as u32;
let bgc = color.green as u32;
let bb = color.blue as u32;
let r = (br + mul_blend_u8(fr.wrapping_sub(br), a)) as u8;
let g = (bgc + mul_blend_u8(fg.wrapping_sub(bgc), a)) as u8;
let b = (bb + mul_blend_u8(fb.wrapping_sub(bb), a)) as u8;
self.0 = Rgb888::new(r, g, b);
self.1 = a as u8;
}
fn from_rgb(red: u8, green: u8, blue: u8) -> Self {
Self(Rgb888::new(red, green, blue), 255)
}
}
impl From<(u8, u8, u8, u8)> for Rgba<Rgb888> {
fn from(value: (u8, u8, u8, u8)) -> Self {
Self(Rgb888::new(value.0, value.1, value.2), value.3)
}
}
impl From<Color> for Rgba<Rgb888> {
fn from(value: Color) -> Self {
Self(Rgb888::new(value.red, value.green, value.blue), value.alpha)
}
}