diff --git a/crates/ecolor/src/color32.rs b/crates/ecolor/src/color32.rs
index 939626425178..09e68116f09b 100644
--- a/crates/ecolor/src/color32.rs
+++ b/crates/ecolor/src/color32.rs
@@ -198,4 +198,19 @@ impl Color32 {
// we need a somewhat expensive conversion to linear space and back.
Rgba::from(self).multiply(factor).into()
}
+
+ /// Converts to floating point values in the range 0-1 without any gamma space conversion.
+ ///
+ /// Use this with great care! In almost all cases, you want to convert to [`crate::Rgba`] instead
+ /// in order to obtain linear space color values.
+ #[inline]
+ pub fn to_normalized_gamma_f32(self) -> [f32; 4] {
+ let Self([r, g, b, a]) = self;
+ [
+ r as f32 / 255.0,
+ g as f32 / 255.0,
+ b as f32 / 255.0,
+ a as f32 / 255.0,
+ ]
+ }
}
diff --git a/crates/eframe/CHANGELOG.md b/crates/eframe/CHANGELOG.md
index 0f67c3db33e6..9dfbb6fc728b 100644
--- a/crates/eframe/CHANGELOG.md
+++ b/crates/eframe/CHANGELOG.md
@@ -5,6 +5,7 @@ NOTE: [`egui-winit`](../egui-winit/CHANGELOG.md), [`egui_glium`](../egui_glium/C
## Unreleased
+* ⚠️ BREAKING: `App::clear_color` now expects you to return a raw float array ([#2666](https://github.com/emilk/egui/pull/2666)):
#### Desktop/Native:
* `eframe::run_native` now returns a `Result` ([#2433](https://github.com/emilk/egui/pull/2433)).
diff --git a/crates/eframe/src/epi.rs b/crates/eframe/src/epi.rs
index 5f2f903ab881..084845a0d00f 100644
--- a/crates/eframe/src/epi.rs
+++ b/crates/eframe/src/epi.rs
@@ -149,13 +149,21 @@ pub trait App {
egui::Vec2::INFINITY
}
- /// Background color for the app, e.g. what is sent to `gl.clearColor`.
+ /// Background color values for the app, e.g. what is sent to `gl.clearColor`.
+ ///
/// This is the background of your windows if you don't set a central panel.
- fn clear_color(&self, _visuals: &egui::Visuals) -> egui::Rgba {
+ ///
+ /// ATTENTION:
+ /// Since these float values go to the render as-is, any color space conversion as done
+ /// e.g. by converting from [`egui::Color32`] to [`egui::Rgba`] may cause incorrect results.
+ /// egui recommends that rendering backends use a normal "gamma-space" (non-sRGB-aware) blending,
+ /// which means the values you return here should also be in `sRGB` gamma-space in the 0-1 range.
+ /// You can use [`egui::Color32::to_normalized_gamma_f32`] for this.
+ fn clear_color(&self, _visuals: &egui::Visuals) -> [f32; 4] {
// NOTE: a bright gray makes the shadows of the windows look weird.
// We use a bit of transparency so that if the user switches on the
// `transparent()` option they get immediate results.
- egui::Color32::from_rgba_unmultiplied(12, 12, 12, 180).into()
+ egui::Color32::from_rgba_unmultiplied(12, 12, 12, 180).to_normalized_gamma_f32()
// _visuals.window_fill() would also be a natural choice
}
diff --git a/crates/eframe/src/web/web_painter.rs b/crates/eframe/src/web/web_painter.rs
index 4ced22f46de3..9c7631b90eb9 100644
--- a/crates/eframe/src/web/web_painter.rs
+++ b/crates/eframe/src/web/web_painter.rs
@@ -1,4 +1,3 @@
-use egui::Rgba;
use wasm_bindgen::JsValue;
/// Renderer for a browser canvas.
@@ -19,7 +18,7 @@ pub(crate) trait WebPainter {
/// Update all internal textures and paint gui.
fn paint_and_update_textures(
&mut self,
- clear_color: Rgba,
+ clear_color: [f32; 4],
clipped_primitives: &[egui::ClippedPrimitive],
pixels_per_point: f32,
textures_delta: &egui::TexturesDelta,
diff --git a/crates/eframe/src/web/web_painter_glow.rs b/crates/eframe/src/web/web_painter_glow.rs
index 36f42692637b..0fe7e12743db 100644
--- a/crates/eframe/src/web/web_painter_glow.rs
+++ b/crates/eframe/src/web/web_painter_glow.rs
@@ -2,7 +2,6 @@ use wasm_bindgen::JsCast;
use wasm_bindgen::JsValue;
use web_sys::HtmlCanvasElement;
-use egui::Rgba;
use egui_glow::glow;
use crate::{WebGlContextOption, WebOptions};
@@ -49,7 +48,7 @@ impl WebPainter for WebPainterGlow {
fn paint_and_update_textures(
&mut self,
- clear_color: Rgba,
+ clear_color: [f32; 4],
clipped_primitives: &[egui::ClippedPrimitive],
pixels_per_point: f32,
textures_delta: &egui::TexturesDelta,
diff --git a/crates/eframe/src/web/web_painter_wgpu.rs b/crates/eframe/src/web/web_painter_wgpu.rs
index d6445f0ef86c..ab55373f33e5 100644
--- a/crates/eframe/src/web/web_painter_wgpu.rs
+++ b/crates/eframe/src/web/web_painter_wgpu.rs
@@ -3,7 +3,7 @@ use std::sync::Arc;
use wasm_bindgen::JsValue;
use web_sys::HtmlCanvasElement;
-use egui::{mutex::RwLock, Rgba};
+use egui::mutex::RwLock;
use egui_wgpu::{renderer::ScreenDescriptor, RenderState, SurfaceErrorAction};
use crate::WebOptions;
@@ -135,7 +135,7 @@ impl WebPainter for WebPainterWgpu {
fn paint_and_update_textures(
&mut self,
- clear_color: Rgba,
+ clear_color: [f32; 4],
clipped_primitives: &[egui::ClippedPrimitive],
pixels_per_point: f32,
textures_delta: &egui::TexturesDelta,
@@ -228,10 +228,10 @@ impl WebPainter for WebPainterWgpu {
resolve_target: None,
ops: wgpu::Operations {
load: wgpu::LoadOp::Clear(wgpu::Color {
- r: clear_color.r() as f64,
- g: clear_color.g() as f64,
- b: clear_color.b() as f64,
- a: clear_color.a() as f64,
+ r: clear_color[0] as f64,
+ g: clear_color[1] as f64,
+ b: clear_color[2] as f64,
+ a: clear_color[3] as f64,
}),
store: true,
},
diff --git a/crates/egui-wgpu/src/winit.rs b/crates/egui-wgpu/src/winit.rs
index 5159304047ce..d10f119457fe 100644
--- a/crates/egui-wgpu/src/winit.rs
+++ b/crates/egui-wgpu/src/winit.rs
@@ -255,7 +255,7 @@ impl Painter {
pub fn paint_and_update_textures(
&mut self,
pixels_per_point: f32,
- clear_color: epaint::Rgba,
+ clear_color: [f32; 4],
clipped_primitives: &[epaint::ClippedPrimitive],
textures_delta: &epaint::textures::TexturesDelta,
) {
@@ -335,10 +335,10 @@ impl Painter {
resolve_target: None,
ops: wgpu::Operations {
load: wgpu::LoadOp::Clear(wgpu::Color {
- r: clear_color.r() as f64,
- g: clear_color.g() as f64,
- b: clear_color.b() as f64,
- a: clear_color.a() as f64,
+ r: clear_color[0] as f64,
+ g: clear_color[1] as f64,
+ b: clear_color[2] as f64,
+ a: clear_color[3] as f64,
}),
store: true,
},
diff --git a/crates/egui_demo_app/src/wrap_app.rs b/crates/egui_demo_app/src/wrap_app.rs
index 2bbf31ebde5e..3f2f5a0a2f50 100644
--- a/crates/egui_demo_app/src/wrap_app.rs
+++ b/crates/egui_demo_app/src/wrap_app.rs
@@ -175,8 +175,8 @@ impl eframe::App for WrapApp {
eframe::set_value(storage, eframe::APP_KEY, &self.state);
}
- fn clear_color(&self, visuals: &egui::Visuals) -> egui::Rgba {
- visuals.panel_fill.into()
+ fn clear_color(&self, visuals: &egui::Visuals) -> [f32; 4] {
+ visuals.panel_fill.to_normalized_gamma_f32()
}
fn update(&mut self, ctx: &egui::Context, frame: &mut eframe::Frame) {
diff --git a/crates/egui_glow/src/painter.rs b/crates/egui_glow/src/painter.rs
index 27f5571c86ea..574ff1e7726d 100644
--- a/crates/egui_glow/src/painter.rs
+++ b/crates/egui_glow/src/painter.rs
@@ -5,7 +5,7 @@ use std::{collections::HashMap, sync::Arc};
use egui::{
emath::Rect,
- epaint::{Color32, Mesh, PaintCallbackInfo, Primitive, Vertex},
+ epaint::{Mesh, PaintCallbackInfo, Primitive, Vertex},
};
use glow::HasContext as _;
use memoffset::offset_of;
@@ -665,7 +665,7 @@ impl Painter {
}
}
-pub fn clear(gl: &glow::Context, screen_size_in_pixels: [u32; 2], clear_color: egui::Rgba) {
+pub fn clear(gl: &glow::Context, screen_size_in_pixels: [u32; 2], clear_color: [f32; 4]) {
crate::profile_function!();
unsafe {
gl.disable(glow::SCISSOR_TEST);
@@ -676,24 +676,12 @@ pub fn clear(gl: &glow::Context, screen_size_in_pixels: [u32; 2], clear_color: e
screen_size_in_pixels[0] as i32,
screen_size_in_pixels[1] as i32,
);
-
- if true {
- // verified to be correct on eframe native (on Mac).
- gl.clear_color(
- clear_color[0],
- clear_color[1],
- clear_color[2],
- clear_color[3],
- );
- } else {
- let clear_color: Color32 = clear_color.into();
- gl.clear_color(
- clear_color[0] as f32 / 255.0,
- clear_color[1] as f32 / 255.0,
- clear_color[2] as f32 / 255.0,
- clear_color[3] as f32 / 255.0,
- );
- }
+ gl.clear_color(
+ clear_color[0],
+ clear_color[1],
+ clear_color[2],
+ clear_color[3],
+ );
gl.clear(glow::COLOR_BUFFER_BIT);
}
}
diff --git a/examples/custom_window_frame/src/main.rs b/examples/custom_window_frame/src/main.rs
index d6a35416bdd8..284451db7ea7 100644
--- a/examples/custom_window_frame/src/main.rs
+++ b/examples/custom_window_frame/src/main.rs
@@ -25,8 +25,8 @@ fn main() -> Result<(), eframe::Error> {
struct MyApp {}
impl eframe::App for MyApp {
- fn clear_color(&self, _visuals: &egui::Visuals) -> egui::Rgba {
- egui::Rgba::TRANSPARENT // Make sure we don't paint anything behind the rounded corners
+ fn clear_color(&self, _visuals: &egui::Visuals) -> [f32; 4] {
+ egui::Rgba::TRANSPARENT.to_array() // Make sure we don't paint anything behind the rounded corners
}
fn update(&mut self, ctx: &egui::Context, frame: &mut eframe::Frame) {