neveko/nevmes-gui/crates/egui_glium/examples/native_texture.rs
2023-04-30 11:55:41 -04:00

139 lines
5.1 KiB
Rust

#![cfg_attr(not(debug_assertions), windows_subsystem = "windows")] // hide console window on Windows in release
use glium::glutin;
fn main() {
let event_loop = glutin::event_loop::EventLoopBuilder::with_user_event().build();
let display = create_display(&event_loop);
let mut egui_glium = egui_glium::EguiGlium::new(&display, &event_loop);
let png_data = include_bytes!("../../../examples/retained_image/src/rust-logo-256x256.png");
let image = load_glium_image(png_data);
let image_size = egui::vec2(image.width as f32, image.height as f32);
// Load to gpu memory
let glium_texture = glium::texture::SrgbTexture2d::new(&display, image).unwrap();
// Allow us to share the texture with egui:
let glium_texture = std::rc::Rc::new(glium_texture);
// Allocate egui's texture id for GL texture
let texture_id = egui_glium
.painter
.register_native_texture(glium_texture, Default::default());
// Setup button image size for reasonable image size for button container.
let button_image_size = egui::vec2(32_f32, 32_f32);
event_loop.run(move |event, _, control_flow| {
let mut redraw = || {
let mut quit = false;
let repaint_after = egui_glium.run(&display, |egui_ctx| {
egui::SidePanel::left("my_side_panel").show(egui_ctx, |ui| {
if ui
.add(egui::Button::image_and_text(
texture_id,
button_image_size,
"Quit",
))
.clicked()
{
quit = true;
}
});
egui::Window::new("NativeTextureDisplay").show(egui_ctx, |ui| {
ui.image(texture_id, image_size);
});
});
*control_flow = if quit {
glutin::event_loop::ControlFlow::Exit
} else if repaint_after.is_zero() {
display.gl_window().window().request_redraw();
glutin::event_loop::ControlFlow::Poll
} else if let Some(repaint_after_instant) =
std::time::Instant::now().checked_add(repaint_after)
{
glutin::event_loop::ControlFlow::WaitUntil(repaint_after_instant)
} else {
glutin::event_loop::ControlFlow::Wait
};
{
use glium::Surface as _;
let mut target = display.draw();
let color = egui::Rgba::from_rgb(0.1, 0.3, 0.2);
target.clear_color(color[0], color[1], color[2], color[3]);
// draw things behind egui here
egui_glium.paint(&display, &mut target);
// draw things on top of egui here
target.finish().unwrap();
}
};
match event {
// Platform-dependent event handlers to workaround a winit bug
// See: https://github.com/rust-windowing/winit/issues/987
// See: https://github.com/rust-windowing/winit/issues/1619
glutin::event::Event::RedrawEventsCleared if cfg!(windows) => redraw(),
glutin::event::Event::RedrawRequested(_) if !cfg!(windows) => redraw(),
glutin::event::Event::WindowEvent { event, .. } => {
use glutin::event::WindowEvent;
if matches!(event, WindowEvent::CloseRequested | WindowEvent::Destroyed) {
*control_flow = glutin::event_loop::ControlFlow::Exit;
}
let event_response = egui_glium.on_event(&event);
if event_response.repaint {
display.gl_window().window().request_redraw();
}
}
glutin::event::Event::NewEvents(glutin::event::StartCause::ResumeTimeReached {
..
}) => {
display.gl_window().window().request_redraw();
}
_ => (),
}
});
}
fn create_display(event_loop: &glutin::event_loop::EventLoop<()>) -> glium::Display {
let window_builder = glutin::window::WindowBuilder::new()
.with_resizable(true)
.with_inner_size(glutin::dpi::LogicalSize {
width: 800.0,
height: 600.0,
})
.with_title("egui_glium example");
let context_builder = glutin::ContextBuilder::new()
.with_depth_buffer(0)
.with_stencil_buffer(0)
.with_vsync(true);
glium::Display::new(window_builder, context_builder, event_loop).unwrap()
}
fn load_glium_image(png_data: &[u8]) -> glium::texture::RawImage2d<'_, u8> {
// Load image using the image crate:
let image = image::load_from_memory(png_data).unwrap().to_rgba8();
let image_dimensions = image.dimensions();
// Premultiply alpha:
let pixels: Vec<_> = image
.into_vec()
.chunks_exact(4)
.map(|p| egui::Color32::from_rgba_unmultiplied(p[0], p[1], p[2], p[3]))
.flat_map(|color| color.to_array())
.collect();
// Convert to glium image:
glium::texture::RawImage2d::from_raw_rgba(pixels, image_dimensions)
}