vendor

egui/crates/egui-wgpu/CHANGELOG.md

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+# Changelog for egui-wgpu
+All notable changes to the `egui-wgpu` integration will be noted in this file.
+
+
+## Unreleased
+* Add `read_screen_rgba` to the egui-wgpu `Painter`, to allow for capturing the current frame when using wgpu. Used in conjunction with `Frame::request_screenshot`. ([#2676](https://github.com/emilk/egui/pull/2676))
+* Improve performance of `update_buffers` ([#2820](https://github.com/emilk/egui/pull/2820))
+* Added support for multisampling (MSAA) ([#2878](https://github.com/emilk/egui/pull/2878))
+
+
+## 0.21.0 - 2023-02-08
+* Update to `wgpu` 0.15 ([#2629](https://github.com/emilk/egui/pull/2629))
+* Return `Err` instead of panic if we can't find a device ([#2428](https://github.com/emilk/egui/pull/2428)).
+* `winit::Painter::set_window` is now `async` ([#2434](https://github.com/emilk/egui/pull/2434)).
+* `egui-wgpu` now only depends on `epaint` instead of the entire `egui` ([#2438](https://github.com/emilk/egui/pull/2438)).
+* `winit::Painter` now supports transparent backbuffer ([#2684](https://github.com/emilk/egui/pull/2684)).
+
+
+## 0.20.0 - 2022-12-08 - web support
+* Renamed `RenderPass` to `Renderer`.
+* Renamed `RenderPass::execute` to `RenderPass::render`.
+* Renamed `RenderPass::execute_with_renderpass` to `Renderer::render` (replacing existing `Renderer::render`)
+* Reexported `Renderer`.
+* You can now use `egui-wgpu` on web, using WebGL ([#2107](https://github.com/emilk/egui/pull/2107)).
+* `Renderer` no longer handles pass creation and depth buffer creation ([#2136](https://github.com/emilk/egui/pull/2136))
+* `PrepareCallback` now passes `wgpu::CommandEncoder` ([#2136](https://github.com/emilk/egui/pull/2136))
+* `PrepareCallback` can now returns `wgpu::CommandBuffer` that are bundled into a single `wgpu::Queue::submit` call ([#2230](https://github.com/emilk/egui/pull/2230))
+* Only a single vertex & index buffer is now created and resized when necessary (previously, vertex/index buffers were allocated for every mesh) ([#2148](https://github.com/emilk/egui/pull/2148)).
+* `Renderer::update_texture` no longer creates a new `wgpu::Sampler` with every new texture ([#2198](https://github.com/emilk/egui/pull/2198))
+* `Painter`'s instance/device/adapter/surface creation is now configurable via `WgpuConfiguration` ([#2207](https://github.com/emilk/egui/pull/2207))
+* Fix panic on using a depth buffer ([#2316](https://github.com/emilk/egui/pull/2316))
+
+
+## 0.19.0 - 2022-08-20
+* Enables deferred render + surface state initialization for Android ([#1634](https://github.com/emilk/egui/pull/1634)).
+* Make `RenderPass` `Send` and `Sync` ([#1883](https://github.com/emilk/egui/pull/1883)).
+
+
+## 0.18.0 - 2022-05-15
+First published version since moving the code into the `egui` repository from <https://github.com/LU15W1R7H/eww>.

egui/crates/egui-wgpu/Cargo.toml

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+[package]
+name = "egui-wgpu"
+version = "0.21.0"
+description = "Bindings for using egui natively using the wgpu library"
+authors = [
+  "Nils Hasenbanck <nils@hasenbanck.de>",
+  "embotech <opensource@embotech.com>",
+  "Emil Ernerfeldt <emil.ernerfeldt@gmail.com>",
+]
+edition = "2021"
+rust-version = "1.65"
+homepage = "https://github.com/emilk/egui/tree/master/crates/egui-wgpu"
+license = "MIT OR Apache-2.0"
+readme = "README.md"
+repository = "https://github.com/emilk/egui/tree/master/crates/egui-wgpu"
+categories = ["gui", "game-development"]
+keywords = ["wgpu", "egui", "gui", "gamedev"]
+include = [
+  "../LICENSE-APACHE",
+  "../LICENSE-MIT",
+  "**/*.rs",
+  "**/*.wgsl",
+  "Cargo.toml",
+]
+
+[package.metadata.docs.rs]
+all-features = true
+
+
+[features]
+## Enable profiling with the [`puffin`](https://docs.rs/puffin) crate.
+puffin = ["dep:puffin"]
+
+## Enable [`winit`](https://docs.rs/winit) integration.
+winit = ["dep:winit"]
+
+
+[dependencies]
+epaint = { version = "0.21.0", path = "../epaint", default-features = false, features = [
+  "bytemuck",
+] }
+
+bytemuck = "1.7"
+tracing = { version = "0.1", default-features = false, features = ["std"] }
+type-map = "0.5.0"
+wgpu = "0.15.0"
+
+#! ### Optional dependencies
+## Enable this when generating docs.
+document-features = { version = "0.2", optional = true }
+
+winit = { version = "0.28", optional = true }
+
+# Native:
+[target.'cfg(not(target_arch = "wasm32"))'.dependencies]
+puffin = { version = "0.14", optional = true }

egui/crates/egui-wgpu/README.md

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+# egui-wgpu
+
+[![Latest version](https://img.shields.io/crates/v/egui-wgpu.svg)](https://crates.io/crates/egui-wgpu)
+[![Documentation](https://docs.rs/egui-wgpu/badge.svg)](https://docs.rs/egui-wgpu)
+![MIT](https://img.shields.io/badge/license-MIT-blue.svg)
+![Apache](https://img.shields.io/badge/license-Apache-blue.svg)
+
+This crates provides bindings between [`egui`](https://github.com/emilk/egui) and [wgpu](https://crates.io/crates/wgpu).
+
+This was originally hosted at https://github.com/hasenbanck/egui_wgpu_backend

egui/crates/egui-wgpu/src/egui.wgsl

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+// Vertex shader bindings
+
+struct VertexOutput {
+    @location(0) tex_coord: vec2<f32>,
+    @location(1) color: vec4<f32>, // gamma 0-1
+    @builtin(position) position: vec4<f32>,
+};
+
+struct Locals {
+    screen_size: vec2<f32>,
+    // Uniform buffers need to be at least 16 bytes in WebGL.
+    // See https://github.com/gfx-rs/wgpu/issues/2072
+    _padding: vec2<u32>,
+};
+@group(0) @binding(0) var<uniform> r_locals: Locals;
+
+// 0-1 linear  from  0-1 sRGB gamma
+fn linear_from_gamma_rgb(srgb: vec3<f32>) -> vec3<f32> {
+    let cutoff = srgb < vec3<f32>(0.04045);
+    let lower = srgb / vec3<f32>(12.92);
+    let higher = pow((srgb + vec3<f32>(0.055)) / vec3<f32>(1.055), vec3<f32>(2.4));
+    return select(higher, lower, cutoff);
+}
+
+// 0-1 sRGB gamma  from  0-1 linear
+fn gamma_from_linear_rgb(rgb: vec3<f32>) -> vec3<f32> {
+    let cutoff = rgb < vec3<f32>(0.0031308);
+    let lower = rgb * vec3<f32>(12.92);
+    let higher = vec3<f32>(1.055) * pow(rgb, vec3<f32>(1.0 / 2.4)) - vec3<f32>(0.055);
+    return select(higher, lower, cutoff);
+}
+
+// 0-1 sRGBA gamma  from  0-1 linear
+fn gamma_from_linear_rgba(linear_rgba: vec4<f32>) -> vec4<f32> {
+    return vec4<f32>(gamma_from_linear_rgb(linear_rgba.rgb), linear_rgba.a);
+}
+
+// [u8; 4] SRGB as u32 -> [r, g, b, a] in 0.-1
+fn unpack_color(color: u32) -> vec4<f32> {
+    return vec4<f32>(
+        f32(color & 255u),
+        f32((color >> 8u) & 255u),
+        f32((color >> 16u) & 255u),
+        f32((color >> 24u) & 255u),
+    ) / 255.0;
+}
+
+fn position_from_screen(screen_pos: vec2<f32>) -> vec4<f32> {
+    return vec4<f32>(
+        2.0 * screen_pos.x / r_locals.screen_size.x - 1.0,
+        1.0 - 2.0 * screen_pos.y / r_locals.screen_size.y,
+        0.0,
+        1.0,
+    );
+}
+
+@vertex
+fn vs_main(
+    @location(0) a_pos: vec2<f32>,
+    @location(1) a_tex_coord: vec2<f32>,
+    @location(2) a_color: u32,
+) -> VertexOutput {
+    var out: VertexOutput;
+    out.tex_coord = a_tex_coord;
+    out.color = unpack_color(a_color);
+    out.position = position_from_screen(a_pos);
+    return out;
+}
+
+// Fragment shader bindings
+
+@group(1) @binding(0) var r_tex_color: texture_2d<f32>;
+@group(1) @binding(1) var r_tex_sampler: sampler;
+
+@fragment
+fn fs_main_linear_framebuffer(in: VertexOutput) -> @location(0) vec4<f32> {
+    // We always have an sRGB aware texture at the moment.
+    let tex_linear = textureSample(r_tex_color, r_tex_sampler, in.tex_coord);
+    let tex_gamma = gamma_from_linear_rgba(tex_linear);
+    let out_color_gamma = in.color * tex_gamma;
+    return vec4<f32>(linear_from_gamma_rgb(out_color_gamma.rgb), out_color_gamma.a);
+}
+
+@fragment
+fn fs_main_gamma_framebuffer(in: VertexOutput) -> @location(0) vec4<f32> {
+    // We always have an sRGB aware texture at the moment.
+    let tex_linear = textureSample(r_tex_color, r_tex_sampler, in.tex_coord);
+    let tex_gamma = gamma_from_linear_rgba(tex_linear);
+    let out_color_gamma = in.color * tex_gamma;
+    return out_color_gamma;
+}

egui/crates/egui-wgpu/src/lib.rs

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+//! This crates provides bindings between [`egui`](https://github.com/emilk/egui) and [wgpu](https://crates.io/crates/wgpu).
+//!
+//! ## Feature flags
+#![cfg_attr(feature = "document-features", doc = document_features::document_features!())]
+//!
+
+#![allow(unsafe_code)]
+
+pub use wgpu;
+
+/// Low-level painting of [`egui`](https://github.com/emilk/egui) on [`wgpu`].
+pub mod renderer;
+pub use renderer::CallbackFn;
+pub use renderer::Renderer;
+
+/// Module for painting [`egui`](https://github.com/emilk/egui) with [`wgpu`] on [`winit`].
+#[cfg(feature = "winit")]
+pub mod winit;
+
+use std::sync::Arc;
+
+use epaint::mutex::RwLock;
+
+/// Access to the render state for egui.
+#[derive(Clone)]
+pub struct RenderState {
+    pub device: Arc<wgpu::Device>,
+    pub queue: Arc<wgpu::Queue>,
+    pub target_format: wgpu::TextureFormat,
+    pub renderer: Arc<RwLock<Renderer>>,
+}
+
+/// Specifies which action should be taken as consequence of a [`wgpu::SurfaceError`]
+pub enum SurfaceErrorAction {
+    /// Do nothing and skip the current frame.
+    SkipFrame,
+
+    /// Instructs egui to recreate the surface, then skip the current frame.
+    RecreateSurface,
+}
+
+/// Configuration for using wgpu with eframe or the egui-wgpu winit feature.
+#[derive(Clone)]
+pub struct WgpuConfiguration {
+    /// Configuration passed on device request.
+    pub device_descriptor: wgpu::DeviceDescriptor<'static>,
+
+    /// Backends that should be supported (wgpu will pick one of these)
+    pub backends: wgpu::Backends,
+
+    /// Present mode used for the primary surface.
+    pub present_mode: wgpu::PresentMode,
+
+    /// Power preference for the adapter.
+    pub power_preference: wgpu::PowerPreference,
+
+    /// Callback for surface errors.
+    pub on_surface_error: Arc<dyn Fn(wgpu::SurfaceError) -> SurfaceErrorAction>,
+
+    pub depth_format: Option<wgpu::TextureFormat>,
+}
+
+impl Default for WgpuConfiguration {
+    fn default() -> Self {
+        Self {
+            device_descriptor: wgpu::DeviceDescriptor {
+                label: Some("egui wgpu device"),
+                features: wgpu::Features::default(),
+                limits: wgpu::Limits::default(),
+            },
+            backends: wgpu::Backends::PRIMARY | wgpu::Backends::GL,
+            present_mode: wgpu::PresentMode::AutoVsync,
+            power_preference: wgpu::PowerPreference::HighPerformance,
+            depth_format: None,
+
+            on_surface_error: Arc::new(|err| {
+                if err == wgpu::SurfaceError::Outdated {
+                    // This error occurs when the app is minimized on Windows.
+                    // Silently return here to prevent spamming the console with:
+                    // "The underlying surface has changed, and therefore the swap chain must be updated"
+                } else {
+                    tracing::warn!("Dropped frame with error: {err}");
+                }
+                SurfaceErrorAction::SkipFrame
+            }),
+        }
+    }
+}
+
+/// Find the framebuffer format that egui prefers
+pub fn preferred_framebuffer_format(formats: &[wgpu::TextureFormat]) -> wgpu::TextureFormat {
+    for &format in formats {
+        if matches!(
+            format,
+            wgpu::TextureFormat::Rgba8Unorm | wgpu::TextureFormat::Bgra8Unorm
+        ) {
+            return format;
+        }
+    }
+    formats[0] // take the first
+}
+// maybe use this-error?
+#[derive(Debug)]
+pub enum WgpuError {
+    DeviceError(wgpu::RequestDeviceError),
+    SurfaceError(wgpu::CreateSurfaceError),
+}
+
+impl std::fmt::Display for WgpuError {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Debug::fmt(self, f)
+    }
+}
+
+impl std::error::Error for WgpuError {
+    fn source(&self) -> Option<&(dyn std::error::Error + 'static)> {
+        match self {
+            WgpuError::DeviceError(e) => e.source(),
+            WgpuError::SurfaceError(e) => e.source(),
+        }
+    }
+}
+
+impl From<wgpu::RequestDeviceError> for WgpuError {
+    fn from(e: wgpu::RequestDeviceError) -> Self {
+        Self::DeviceError(e)
+    }
+}
+
+impl From<wgpu::CreateSurfaceError> for WgpuError {
+    fn from(e: wgpu::CreateSurfaceError) -> Self {
+        Self::SurfaceError(e)
+    }
+}
+// ---------------------------------------------------------------------------
+
+/// Profiling macro for feature "puffin"
+macro_rules! profile_function {
+    ($($arg: tt)*) => {
+        #[cfg(feature = "puffin")]
+        #[cfg(not(target_arch = "wasm32"))]
+        puffin::profile_function!($($arg)*);
+    };
+}
+pub(crate) use profile_function;
+
+/// Profiling macro for feature "puffin"
+macro_rules! profile_scope {
+    ($($arg: tt)*) => {
+        #[cfg(feature = "puffin")]
+        #[cfg(not(target_arch = "wasm32"))]
+        puffin::profile_scope!($($arg)*);
+    };
+}
+pub(crate) use profile_scope;

egui/crates/egui-wgpu/src/renderer.rs

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+#![allow(unsafe_code)]
+
+use std::num::NonZeroU64;
+use std::ops::Range;
+use std::{borrow::Cow, collections::HashMap, num::NonZeroU32};
+
+use type_map::concurrent::TypeMap;
+use wgpu;
+use wgpu::util::DeviceExt as _;
+
+use epaint::{emath::NumExt, PaintCallbackInfo, Primitive, Vertex};
+
+/// A callback function that can be used to compose an [`epaint::PaintCallback`] for custom WGPU
+/// rendering.
+///
+/// The callback is composed of two functions: `prepare` and `paint`:
+/// - `prepare` is called every frame before `paint`, and can use the passed-in
+///   [`wgpu::Device`] and [`wgpu::Buffer`] to allocate or modify GPU resources such as buffers.
+/// - `paint` is called after `prepare` and is given access to the [`wgpu::RenderPass`] so
+///   that it can issue draw commands into the same [`wgpu::RenderPass`] that is used for
+///   all other egui elements.
+///
+/// The final argument of both the `prepare` and `paint` callbacks is a the
+/// [`paint_callback_resources`][crate::renderer::Renderer::paint_callback_resources].
+/// `paint_callback_resources` has the same lifetime as the Egui render pass, so it can be used to
+/// store buffers, pipelines, and other information that needs to be accessed during the render
+/// pass.
+///
+/// # Example
+///
+/// See the [`custom3d_wgpu`](https://github.com/emilk/egui/blob/master/crates/egui_demo_app/src/apps/custom3d_wgpu.rs) demo source for a detailed usage example.
+pub struct CallbackFn {
+    prepare: Box<PrepareCallback>,
+    paint: Box<PaintCallback>,
+}
+
+type PrepareCallback = dyn Fn(
+        &wgpu::Device,
+        &wgpu::Queue,
+        &mut wgpu::CommandEncoder,
+        &mut TypeMap,
+    ) -> Vec<wgpu::CommandBuffer>
+    + Sync
+    + Send;
+
+type PaintCallback =
+    dyn for<'a, 'b> Fn(PaintCallbackInfo, &'a mut wgpu::RenderPass<'b>, &'b TypeMap) + Sync + Send;
+
+impl Default for CallbackFn {
+    fn default() -> Self {
+        CallbackFn {
+            prepare: Box::new(|_, _, _, _| Vec::new()),
+            paint: Box::new(|_, _, _| ()),
+        }
+    }
+}
+
+impl CallbackFn {
+    pub fn new() -> Self {
+        Self::default()
+    }
+
+    /// Set the prepare callback.
+    ///
+    /// The passed-in `CommandEncoder` is egui's and can be used directly to register
+    /// wgpu commands for simple use cases.
+    /// This allows reusing the same [`wgpu::CommandEncoder`] for all callbacks and egui
+    /// rendering itself.
+    ///
+    /// For more complicated use cases, one can also return a list of arbitrary
+    /// `CommandBuffer`s and have complete control over how they get created and fed.
+    /// In particular, this gives an opportunity to parallelize command registration and
+    /// prevents a faulty callback from poisoning the main wgpu pipeline.
+    ///
+    /// When using eframe, the main egui command buffer, as well as all user-defined
+    /// command buffers returned by this function, are guaranteed to all be submitted
+    /// at once in a single call.
+    pub fn prepare<F>(mut self, prepare: F) -> Self
+    where
+        F: Fn(
+                &wgpu::Device,
+                &wgpu::Queue,
+                &mut wgpu::CommandEncoder,
+                &mut TypeMap,
+            ) -> Vec<wgpu::CommandBuffer>
+            + Sync
+            + Send
+            + 'static,
+    {
+        self.prepare = Box::new(prepare) as _;
+        self
+    }
+
+    /// Set the paint callback
+    pub fn paint<F>(mut self, paint: F) -> Self
+    where
+        F: for<'a, 'b> Fn(PaintCallbackInfo, &'a mut wgpu::RenderPass<'b>, &'b TypeMap)
+            + Sync
+            + Send
+            + 'static,
+    {
+        self.paint = Box::new(paint) as _;
+        self
+    }
+}
+
+/// Information about the screen used for rendering.
+pub struct ScreenDescriptor {
+    /// Size of the window in physical pixels.
+    pub size_in_pixels: [u32; 2],
+
+    /// HiDPI scale factor (pixels per point).
+    pub pixels_per_point: f32,
+}
+
+impl ScreenDescriptor {
+    /// size in "logical" points
+    fn screen_size_in_points(&self) -> [f32; 2] {
+        [
+            self.size_in_pixels[0] as f32 / self.pixels_per_point,
+            self.size_in_pixels[1] as f32 / self.pixels_per_point,
+        ]
+    }
+}
+
+/// Uniform buffer used when rendering.
+#[derive(Clone, Copy, Debug, bytemuck::Pod, bytemuck::Zeroable)]
+#[repr(C)]
+struct UniformBuffer {
+    screen_size_in_points: [f32; 2],
+    // Uniform buffers need to be at least 16 bytes in WebGL.
+    // See https://github.com/gfx-rs/wgpu/issues/2072
+    _padding: [u32; 2],
+}
+
+impl PartialEq for UniformBuffer {
+    fn eq(&self, other: &Self) -> bool {
+        self.screen_size_in_points == other.screen_size_in_points
+    }
+}
+
+struct SlicedBuffer {
+    buffer: wgpu::Buffer,
+    slices: Vec<Range<usize>>,
+    capacity: wgpu::BufferAddress,
+}
+
+/// Renderer for a egui based GUI.
+pub struct Renderer {
+    pipeline: wgpu::RenderPipeline,
+
+    index_buffer: SlicedBuffer,
+    vertex_buffer: SlicedBuffer,
+
+    uniform_buffer: wgpu::Buffer,
+    previous_uniform_buffer_content: UniformBuffer,
+    uniform_bind_group: wgpu::BindGroup,
+    texture_bind_group_layout: wgpu::BindGroupLayout,
+
+    /// Map of egui texture IDs to textures and their associated bindgroups (texture view +
+    /// sampler). The texture may be None if the TextureId is just a handle to a user-provided
+    /// sampler.
+    textures: HashMap<epaint::TextureId, (Option<wgpu::Texture>, wgpu::BindGroup)>,
+    next_user_texture_id: u64,
+    samplers: HashMap<epaint::textures::TextureOptions, wgpu::Sampler>,
+
+    /// Storage for use by [`epaint::PaintCallback`]'s that need to store resources such as render
+    /// pipelines that must have the lifetime of the renderpass.
+    pub paint_callback_resources: TypeMap,
+}
+
+impl Renderer {
+    /// Creates a renderer for a egui UI.
+    ///
+    /// `output_color_format` should preferably be [`wgpu::TextureFormat::Rgba8Unorm`] or
+    /// [`wgpu::TextureFormat::Bgra8Unorm`], i.e. in gamma-space.
+    pub fn new(
+        device: &wgpu::Device,
+        output_color_format: wgpu::TextureFormat,
+        output_depth_format: Option<wgpu::TextureFormat>,
+        msaa_samples: u32,
+    ) -> Self {
+        crate::profile_function!();
+
+        let shader = wgpu::ShaderModuleDescriptor {
+            label: Some("egui"),
+            source: wgpu::ShaderSource::Wgsl(Cow::Borrowed(include_str!("egui.wgsl"))),
+        };
+        let module = device.create_shader_module(shader);
+
+        let uniform_buffer = device.create_buffer_init(&wgpu::util::BufferInitDescriptor {
+            label: Some("egui_uniform_buffer"),
+            contents: bytemuck::cast_slice(&[UniformBuffer {
+                screen_size_in_points: [0.0, 0.0],
+                _padding: Default::default(),
+            }]),
+            usage: wgpu::BufferUsages::UNIFORM | wgpu::BufferUsages::COPY_DST,
+        });
+
+        let uniform_bind_group_layout =
+            device.create_bind_group_layout(&wgpu::BindGroupLayoutDescriptor {
+                label: Some("egui_uniform_bind_group_layout"),
+                entries: &[wgpu::BindGroupLayoutEntry {
+                    binding: 0,
+                    visibility: wgpu::ShaderStages::VERTEX,
+                    ty: wgpu::BindingType::Buffer {
+                        has_dynamic_offset: false,
+                        min_binding_size: NonZeroU64::new(std::mem::size_of::<UniformBuffer>() as _),
+                        ty: wgpu::BufferBindingType::Uniform,
+                    },
+                    count: None,
+                }],
+            });
+
+        let uniform_bind_group = device.create_bind_group(&wgpu::BindGroupDescriptor {
+            label: Some("egui_uniform_bind_group"),
+            layout: &uniform_bind_group_layout,
+            entries: &[wgpu::BindGroupEntry {
+                binding: 0,
+                resource: wgpu::BindingResource::Buffer(wgpu::BufferBinding {
+                    buffer: &uniform_buffer,
+                    offset: 0,
+                    size: None,
+                }),
+            }],
+        });
+
+        let texture_bind_group_layout =
+            device.create_bind_group_layout(&wgpu::BindGroupLayoutDescriptor {
+                label: Some("egui_texture_bind_group_layout"),
+                entries: &[
+                    wgpu::BindGroupLayoutEntry {
+                        binding: 0,
+                        visibility: wgpu::ShaderStages::FRAGMENT,
+                        ty: wgpu::BindingType::Texture {
+                            multisampled: false,
+                            sample_type: wgpu::TextureSampleType::Float { filterable: true },
+                            view_dimension: wgpu::TextureViewDimension::D2,
+                        },
+                        count: None,
+                    },
+                    wgpu::BindGroupLayoutEntry {
+                        binding: 1,
+                        visibility: wgpu::ShaderStages::FRAGMENT,
+                        ty: wgpu::BindingType::Sampler(wgpu::SamplerBindingType::Filtering),
+                        count: None,
+                    },
+                ],
+            });
+
+        let pipeline_layout = device.create_pipeline_layout(&wgpu::PipelineLayoutDescriptor {
+            label: Some("egui_pipeline_layout"),
+            bind_group_layouts: &[&uniform_bind_group_layout, &texture_bind_group_layout],
+            push_constant_ranges: &[],
+        });
+
+        let depth_stencil = output_depth_format.map(|format| wgpu::DepthStencilState {
+            format,
+            depth_write_enabled: false,
+            depth_compare: wgpu::CompareFunction::Always,
+            stencil: wgpu::StencilState::default(),
+            bias: wgpu::DepthBiasState::default(),
+        });
+
+        let pipeline = device.create_render_pipeline(&wgpu::RenderPipelineDescriptor {
+            label: Some("egui_pipeline"),
+            layout: Some(&pipeline_layout),
+            vertex: wgpu::VertexState {
+                entry_point: "vs_main",
+                module: &module,
+                buffers: &[wgpu::VertexBufferLayout {
+                    array_stride: 5 * 4,
+                    step_mode: wgpu::VertexStepMode::Vertex,
+                    // 0: vec2 position
+                    // 1: vec2 texture coordinates
+                    // 2: uint color
+                    attributes: &wgpu::vertex_attr_array![0 => Float32x2, 1 => Float32x2, 2 => Uint32],
+                }],
+            },
+            primitive: wgpu::PrimitiveState {
+                topology: wgpu::PrimitiveTopology::TriangleList,
+                unclipped_depth: false,
+                conservative: false,
+                cull_mode: None,
+                front_face: wgpu::FrontFace::default(),
+                polygon_mode: wgpu::PolygonMode::default(),
+                strip_index_format: None,
+            },
+            depth_stencil,
+            multisample: wgpu::MultisampleState {
+                alpha_to_coverage_enabled: false,
+                count: msaa_samples,
+                mask: !0,
+            },
+
+            fragment: Some(wgpu::FragmentState {
+                module: &module,
+                entry_point: if output_color_format.describe().srgb {
+                    tracing::warn!("Detected a linear (sRGBA aware) framebuffer {:?}. egui prefers Rgba8Unorm or Bgra8Unorm", output_color_format);
+                    "fs_main_linear_framebuffer"
+                } else {
+                    "fs_main_gamma_framebuffer" // this is what we prefer
+                },
+                targets: &[Some(wgpu::ColorTargetState {
+                    format: output_color_format,
+                    blend: Some(wgpu::BlendState {
+                        color: wgpu::BlendComponent {
+                            src_factor: wgpu::BlendFactor::One,
+                            dst_factor: wgpu::BlendFactor::OneMinusSrcAlpha,
+                            operation: wgpu::BlendOperation::Add,
+                        },
+                        alpha: wgpu::BlendComponent {
+                            src_factor: wgpu::BlendFactor::OneMinusDstAlpha,
+                            dst_factor: wgpu::BlendFactor::One,
+                            operation: wgpu::BlendOperation::Add,
+                        },
+                    }),
+                    write_mask: wgpu::ColorWrites::ALL,
+                })],
+            }),
+            multiview: None,
+        });
+
+        const VERTEX_BUFFER_START_CAPACITY: wgpu::BufferAddress =
+            (std::mem::size_of::<Vertex>() * 1024) as _;
+        const INDEX_BUFFER_START_CAPACITY: wgpu::BufferAddress =
+            (std::mem::size_of::<u32>() * 1024 * 3) as _;
+
+        Self {
+            pipeline,
+            vertex_buffer: SlicedBuffer {
+                buffer: create_vertex_buffer(device, VERTEX_BUFFER_START_CAPACITY),
+                slices: Vec::with_capacity(64),
+                capacity: VERTEX_BUFFER_START_CAPACITY,
+            },
+            index_buffer: SlicedBuffer {
+                buffer: create_index_buffer(device, INDEX_BUFFER_START_CAPACITY),
+                slices: Vec::with_capacity(64),
+                capacity: INDEX_BUFFER_START_CAPACITY,
+            },
+            uniform_buffer,
+            // Buffers on wgpu are zero initialized, so this is indeed its current state!
+            previous_uniform_buffer_content: UniformBuffer {
+                screen_size_in_points: [0.0, 0.0],
+                _padding: [0, 0],
+            },
+            uniform_bind_group,
+            texture_bind_group_layout,
+            textures: HashMap::new(),
+            next_user_texture_id: 0,
+            samplers: HashMap::new(),
+            paint_callback_resources: TypeMap::default(),
+        }
+    }
+
+    /// Executes the egui renderer onto an existing wgpu renderpass.
+    pub fn render<'rp>(
+        &'rp self,
+        render_pass: &mut wgpu::RenderPass<'rp>,
+        paint_jobs: &[epaint::ClippedPrimitive],
+        screen_descriptor: &ScreenDescriptor,
+    ) {
+        crate::profile_function!();
+
+        let pixels_per_point = screen_descriptor.pixels_per_point;
+        let size_in_pixels = screen_descriptor.size_in_pixels;
+
+        // Whether or not we need to reset the render pass because a paint callback has just
+        // run.
+        let mut needs_reset = true;
+
+        let mut index_buffer_slices = self.index_buffer.slices.iter();
+        let mut vertex_buffer_slices = self.vertex_buffer.slices.iter();
+
+        for epaint::ClippedPrimitive {
+            clip_rect,
+            primitive,
+        } in paint_jobs
+        {
+            if needs_reset {
+                render_pass.set_viewport(
+                    0.0,
+                    0.0,
+                    size_in_pixels[0] as f32,
+                    size_in_pixels[1] as f32,
+                    0.0,
+                    1.0,
+                );
+                render_pass.set_pipeline(&self.pipeline);
+                render_pass.set_bind_group(0, &self.uniform_bind_group, &[]);
+                needs_reset = false;
+            }
+
+            {
+                let rect = ScissorRect::new(clip_rect, pixels_per_point, size_in_pixels);
+
+                if rect.width == 0 || rect.height == 0 {
+                    // Skip rendering zero-sized clip areas.
+                    if let Primitive::Mesh(_) = primitive {
+                        // If this is a mesh, we need to advance the index and vertex buffer iterators:
+                        index_buffer_slices.next().unwrap();
+                        vertex_buffer_slices.next().unwrap();
+                    }
+                    continue;
+                }
+
+                render_pass.set_scissor_rect(rect.x, rect.y, rect.width, rect.height);
+            }
+
+            match primitive {
+                Primitive::Mesh(mesh) => {
+                    let index_buffer_slice = index_buffer_slices.next().unwrap();
+                    let vertex_buffer_slice = vertex_buffer_slices.next().unwrap();
+
+                    if let Some((_texture, bind_group)) = self.textures.get(&mesh.texture_id) {
+                        render_pass.set_bind_group(1, bind_group, &[]);
+                        render_pass.set_index_buffer(
+                            self.index_buffer.buffer.slice(
+                                index_buffer_slice.start as u64..index_buffer_slice.end as u64,
+                            ),
+                            wgpu::IndexFormat::Uint32,
+                        );
+                        render_pass.set_vertex_buffer(
+                            0,
+                            self.vertex_buffer.buffer.slice(
+                                vertex_buffer_slice.start as u64..vertex_buffer_slice.end as u64,
+                            ),
+                        );
+                        render_pass.draw_indexed(0..mesh.indices.len() as u32, 0, 0..1);
+                    } else {
+                        tracing::warn!("Missing texture: {:?}", mesh.texture_id);
+                    }
+                }
+                Primitive::Callback(callback) => {
+                    let cbfn = if let Some(c) = callback.callback.downcast_ref::<CallbackFn>() {
+                        c
+                    } else {
+                        // We already warned in the `prepare` callback
+                        continue;
+                    };
+
+                    if callback.rect.is_positive() {
+                        crate::profile_scope!("callback");
+
+                        needs_reset = true;
+
+                        {
+                            // We're setting a default viewport for the render pass as a
+                            // courtesy for the user, so that they don't have to think about
+                            // it in the simple case where they just want to fill the whole
+                            // paint area.
+                            //
+                            // The user still has the possibility of setting their own custom
+                            // viewport during the paint callback, effectively overriding this
+                            // one.
+
+                            let min = (callback.rect.min.to_vec2() * pixels_per_point).round();
+                            let max = (callback.rect.max.to_vec2() * pixels_per_point).round();
+
+                            render_pass.set_viewport(
+                                min.x,
+                                min.y,
+                                max.x - min.x,
+                                max.y - min.y,
+                                0.0,
+                                1.0,
+                            );
+                        }
+
+                        (cbfn.paint)(
+                            PaintCallbackInfo {
+                                viewport: callback.rect,
+                                clip_rect: *clip_rect,
+                                pixels_per_point,
+                                screen_size_px: size_in_pixels,
+                            },
+                            render_pass,
+                            &self.paint_callback_resources,
+                        );
+                    }
+                }
+            }
+        }
+
+        render_pass.set_scissor_rect(0, 0, size_in_pixels[0], size_in_pixels[1]);
+    }
+
+    /// Should be called before `render()`.
+    pub fn update_texture(
+        &mut self,
+        device: &wgpu::Device,
+        queue: &wgpu::Queue,
+        id: epaint::TextureId,
+        image_delta: &epaint::ImageDelta,
+    ) {
+        crate::profile_function!();
+
+        let width = image_delta.image.width() as u32;
+        let height = image_delta.image.height() as u32;
+
+        let size = wgpu::Extent3d {
+            width,
+            height,
+            depth_or_array_layers: 1,
+        };
+
+        let data_color32 = match &image_delta.image {
+            epaint::ImageData::Color(image) => {
+                assert_eq!(
+                    width as usize * height as usize,
+                    image.pixels.len(),
+                    "Mismatch between texture size and texel count"
+                );
+                Cow::Borrowed(&image.pixels)
+            }
+            epaint::ImageData::Font(image) => {
+                assert_eq!(
+                    width as usize * height as usize,
+                    image.pixels.len(),
+                    "Mismatch between texture size and texel count"
+                );
+                Cow::Owned(image.srgba_pixels(None).collect::<Vec<_>>())
+            }
+        };
+        let data_bytes: &[u8] = bytemuck::cast_slice(data_color32.as_slice());
+
+        let queue_write_data_to_texture = |texture, origin| {
+            queue.write_texture(
+                wgpu::ImageCopyTexture {
+                    texture,
+                    mip_level: 0,
+                    origin,
+                    aspect: wgpu::TextureAspect::All,
+                },
+                data_bytes,
+                wgpu::ImageDataLayout {
+                    offset: 0,
+                    bytes_per_row: NonZeroU32::new(4 * width),
+                    rows_per_image: NonZeroU32::new(height),
+                },
+                size,
+            );
+        };
+
+        if let Some(pos) = image_delta.pos {
+            // update the existing texture
+            let (texture, _bind_group) = self
+                .textures
+                .get(&id)
+                .expect("Tried to update a texture that has not been allocated yet.");
+            let origin = wgpu::Origin3d {
+                x: pos[0] as u32,
+                y: pos[1] as u32,
+                z: 0,
+            };
+            queue_write_data_to_texture(
+                texture.as_ref().expect("Tried to update user texture."),
+                origin,
+            );
+        } else {
+            // allocate a new texture
+            // Use same label for all resources associated with this texture id (no point in retyping the type)
+            let label_str = format!("egui_texid_{:?}", id);
+            let label = Some(label_str.as_str());
+            let texture = device.create_texture(&wgpu::TextureDescriptor {
+                label,
+                size,
+                mip_level_count: 1,
+                sample_count: 1,
+                dimension: wgpu::TextureDimension::D2,
+                format: wgpu::TextureFormat::Rgba8UnormSrgb, // Minspec for wgpu WebGL emulation is WebGL2, so this should always be supported.
+                usage: wgpu::TextureUsages::TEXTURE_BINDING | wgpu::TextureUsages::COPY_DST,
+                view_formats: &[wgpu::TextureFormat::Rgba8UnormSrgb],
+            });
+            let sampler = self
+                .samplers
+                .entry(image_delta.options)
+                .or_insert_with(|| create_sampler(image_delta.options, device));
+            let bind_group = device.create_bind_group(&wgpu::BindGroupDescriptor {
+                label,
+                layout: &self.texture_bind_group_layout,
+                entries: &[
+                    wgpu::BindGroupEntry {
+                        binding: 0,
+                        resource: wgpu::BindingResource::TextureView(
+                            &texture.create_view(&wgpu::TextureViewDescriptor::default()),
+                        ),
+                    },
+                    wgpu::BindGroupEntry {
+                        binding: 1,
+                        resource: wgpu::BindingResource::Sampler(sampler),
+                    },
+                ],
+            });
+            let origin = wgpu::Origin3d::ZERO;
+            queue_write_data_to_texture(&texture, origin);
+            self.textures.insert(id, (Some(texture), bind_group));
+        };
+    }
+
+    pub fn free_texture(&mut self, id: &epaint::TextureId) {
+        self.textures.remove(id);
+    }
+
+    /// Get the WGPU texture and bind group associated to a texture that has been allocated by egui.
+    ///
+    /// This could be used by custom paint hooks to render images that have been added through with
+    /// [`egui_extras::RetainedImage`](https://docs.rs/egui_extras/latest/egui_extras/image/struct.RetainedImage.html)
+    /// or [`epaint::Context::load_texture`](https://docs.rs/egui/latest/egui/struct.Context.html#method.load_texture).
+    pub fn texture(
+        &self,
+        id: &epaint::TextureId,
+    ) -> Option<&(Option<wgpu::Texture>, wgpu::BindGroup)> {
+        self.textures.get(id)
+    }
+
+    /// Registers a `wgpu::Texture` with a `epaint::TextureId`.
+    ///
+    /// This enables the application to reference the texture inside an image ui element.
+    /// This effectively enables off-screen rendering inside the egui UI. Texture must have
+    /// the texture format `TextureFormat::Rgba8UnormSrgb` and
+    /// Texture usage `TextureUsage::SAMPLED`.
+    pub fn register_native_texture(
+        &mut self,
+        device: &wgpu::Device,
+        texture: &wgpu::TextureView,
+        texture_filter: wgpu::FilterMode,
+    ) -> epaint::TextureId {
+        self.register_native_texture_with_sampler_options(
+            device,
+            texture,
+            wgpu::SamplerDescriptor {
+                label: Some(format!("egui_user_image_{}", self.next_user_texture_id).as_str()),
+                mag_filter: texture_filter,
+                min_filter: texture_filter,
+                ..Default::default()
+            },
+        )
+    }
+
+    /// Registers a `wgpu::Texture` with an existing `epaint::TextureId`.
+    ///
+    /// This enables applications to reuse `TextureId`s.
+    pub fn update_egui_texture_from_wgpu_texture(
+        &mut self,
+        device: &wgpu::Device,
+        texture: &wgpu::TextureView,
+        texture_filter: wgpu::FilterMode,
+        id: epaint::TextureId,
+    ) {
+        self.update_egui_texture_from_wgpu_texture_with_sampler_options(
+            device,
+            texture,
+            wgpu::SamplerDescriptor {
+                label: Some(format!("egui_user_image_{}", self.next_user_texture_id).as_str()),
+                mag_filter: texture_filter,
+                min_filter: texture_filter,
+                ..Default::default()
+            },
+            id,
+        );
+    }
+
+    /// Registers a `wgpu::Texture` with a `epaint::TextureId` while also accepting custom
+    /// `wgpu::SamplerDescriptor` options.
+    ///
+    /// This allows applications to specify individual minification/magnification filters as well as
+    /// custom mipmap and tiling options.
+    ///
+    /// The `Texture` must have the format `TextureFormat::Rgba8UnormSrgb` and usage
+    /// `TextureUsage::SAMPLED`. Any compare function supplied in the `SamplerDescriptor` will be
+    /// ignored.
+    #[allow(clippy::needless_pass_by_value)] // false positive
+    pub fn register_native_texture_with_sampler_options(
+        &mut self,
+        device: &wgpu::Device,
+        texture: &wgpu::TextureView,
+        sampler_descriptor: wgpu::SamplerDescriptor<'_>,
+    ) -> epaint::TextureId {
+        crate::profile_function!();
+
+        let sampler = device.create_sampler(&wgpu::SamplerDescriptor {
+            compare: None,
+            ..sampler_descriptor
+        });
+
+        let bind_group = device.create_bind_group(&wgpu::BindGroupDescriptor {
+            label: Some(format!("egui_user_image_{}", self.next_user_texture_id).as_str()),
+            layout: &self.texture_bind_group_layout,
+            entries: &[
+                wgpu::BindGroupEntry {
+                    binding: 0,
+                    resource: wgpu::BindingResource::TextureView(texture),
+                },
+                wgpu::BindGroupEntry {
+                    binding: 1,
+                    resource: wgpu::BindingResource::Sampler(&sampler),
+                },
+            ],
+        });
+
+        let id = epaint::TextureId::User(self.next_user_texture_id);
+        self.textures.insert(id, (None, bind_group));
+        self.next_user_texture_id += 1;
+
+        id
+    }
+
+    /// Registers a `wgpu::Texture` with an existing `epaint::TextureId` while also accepting custom
+    /// `wgpu::SamplerDescriptor` options.
+    ///
+    /// This allows applications to reuse `TextureId`s created with custom sampler options.
+    #[allow(clippy::needless_pass_by_value)] // false positive
+    pub fn update_egui_texture_from_wgpu_texture_with_sampler_options(
+        &mut self,
+        device: &wgpu::Device,
+        texture: &wgpu::TextureView,
+        sampler_descriptor: wgpu::SamplerDescriptor<'_>,
+        id: epaint::TextureId,
+    ) {
+        crate::profile_function!();
+
+        let (_user_texture, user_texture_binding) = self
+            .textures
+            .get_mut(&id)
+            .expect("Tried to update a texture that has not been allocated yet.");
+
+        let sampler = device.create_sampler(&wgpu::SamplerDescriptor {
+            compare: None,
+            ..sampler_descriptor
+        });
+
+        let bind_group = device.create_bind_group(&wgpu::BindGroupDescriptor {
+            label: Some(format!("egui_user_image_{}", self.next_user_texture_id).as_str()),
+            layout: &self.texture_bind_group_layout,
+            entries: &[
+                wgpu::BindGroupEntry {
+                    binding: 0,
+                    resource: wgpu::BindingResource::TextureView(texture),
+                },
+                wgpu::BindGroupEntry {
+                    binding: 1,
+                    resource: wgpu::BindingResource::Sampler(&sampler),
+                },
+            ],
+        });
+
+        *user_texture_binding = bind_group;
+    }
+
+    /// Uploads the uniform, vertex and index data used by the renderer.
+    /// Should be called before `render()`.
+    ///
+    /// Returns all user-defined command buffers gathered from prepare callbacks.
+    pub fn update_buffers(
+        &mut self,
+        device: &wgpu::Device,
+        queue: &wgpu::Queue,
+        encoder: &mut wgpu::CommandEncoder,
+        paint_jobs: &[epaint::ClippedPrimitive],
+        screen_descriptor: &ScreenDescriptor,
+    ) -> Vec<wgpu::CommandBuffer> {
+        crate::profile_function!();
+
+        let screen_size_in_points = screen_descriptor.screen_size_in_points();
+
+        let uniform_buffer_content = UniformBuffer {
+            screen_size_in_points,
+            _padding: Default::default(),
+        };
+        if uniform_buffer_content != self.previous_uniform_buffer_content {
+            crate::profile_scope!("update uniforms");
+            queue.write_buffer(
+                &self.uniform_buffer,
+                0,
+                bytemuck::cast_slice(&[uniform_buffer_content]),
+            );
+            self.previous_uniform_buffer_content = uniform_buffer_content;
+        }
+
+        // Determine how many vertices & indices need to be rendered.
+        let (vertex_count, index_count) = {
+            crate::profile_scope!("count_vertices_indices");
+            paint_jobs.iter().fold((0, 0), |acc, clipped_primitive| {
+                match &clipped_primitive.primitive {
+                    Primitive::Mesh(mesh) => {
+                        (acc.0 + mesh.vertices.len(), acc.1 + mesh.indices.len())
+                    }
+                    Primitive::Callback(_) => acc,
+                }
+            })
+        };
+
+        if index_count > 0 {
+            crate::profile_scope!("indices");
+
+            self.index_buffer.slices.clear();
+            let required_index_buffer_size = (std::mem::size_of::<u32>() * index_count) as u64;
+            if self.index_buffer.capacity < required_index_buffer_size {
+                // Resize index buffer if needed.
+                self.index_buffer.capacity =
+                    (self.index_buffer.capacity * 2).at_least(required_index_buffer_size);
+                self.index_buffer.buffer = create_index_buffer(device, self.index_buffer.capacity);
+            }
+
+            let mut index_buffer_staging = queue
+                .write_buffer_with(
+                    &self.index_buffer.buffer,
+                    0,
+                    NonZeroU64::new(required_index_buffer_size).unwrap(),
+                )
+                .expect("Failed to create staging buffer for index data");
+            let mut index_offset = 0;
+            for epaint::ClippedPrimitive { primitive, .. } in paint_jobs.iter() {
+                match primitive {
+                    Primitive::Mesh(mesh) => {
+                        let size = mesh.indices.len() * std::mem::size_of::<u32>();
+                        let slice = index_offset..(size + index_offset);
+                        index_buffer_staging[slice.clone()]
+                            .copy_from_slice(bytemuck::cast_slice(&mesh.indices));
+                        self.index_buffer.slices.push(slice);
+                        index_offset += size;
+                    }
+                    Primitive::Callback(_) => {}
+                }
+            }
+        }
+        if vertex_count > 0 {
+            crate::profile_scope!("vertices");
+
+            self.vertex_buffer.slices.clear();
+            let required_vertex_buffer_size = (std::mem::size_of::<Vertex>() * vertex_count) as u64;
+            if self.vertex_buffer.capacity < required_vertex_buffer_size {
+                // Resize vertex buffer if needed.
+                self.vertex_buffer.capacity =
+                    (self.vertex_buffer.capacity * 2).at_least(required_vertex_buffer_size);
+                self.vertex_buffer.buffer =
+                    create_vertex_buffer(device, self.vertex_buffer.capacity);
+            }
+
+            let mut vertex_buffer_staging = queue
+                .write_buffer_with(
+                    &self.vertex_buffer.buffer,
+                    0,
+                    NonZeroU64::new(required_vertex_buffer_size).unwrap(),
+                )
+                .expect("Failed to create staging buffer for vertex data");
+            let mut vertex_offset = 0;
+            for epaint::ClippedPrimitive { primitive, .. } in paint_jobs.iter() {
+                match primitive {
+                    Primitive::Mesh(mesh) => {
+                        let size = mesh.vertices.len() * std::mem::size_of::<Vertex>();
+                        let slice = vertex_offset..(size + vertex_offset);
+                        vertex_buffer_staging[slice.clone()]
+                            .copy_from_slice(bytemuck::cast_slice(&mesh.vertices));
+                        self.vertex_buffer.slices.push(slice);
+                        vertex_offset += size;
+                    }
+                    Primitive::Callback(_) => {}
+                }
+            }
+        }
+
+        {
+            crate::profile_scope!("user command buffers");
+            let mut user_cmd_bufs = Vec::new(); // collect user command buffers
+            for epaint::ClippedPrimitive { primitive, .. } in paint_jobs.iter() {
+                match primitive {
+                    Primitive::Mesh(_) => {}
+                    Primitive::Callback(callback) => {
+                        let cbfn = if let Some(c) = callback.callback.downcast_ref::<CallbackFn>() {
+                            c
+                        } else {
+                            tracing::warn!(
+                                "Unknown paint callback: expected `egui_wgpu::CallbackFn`"
+                            );
+                            continue;
+                        };
+
+                        crate::profile_scope!("callback");
+                        user_cmd_bufs.extend((cbfn.prepare)(
+                            device,
+                            queue,
+                            encoder,
+                            &mut self.paint_callback_resources,
+                        ));
+                    }
+                }
+            }
+            user_cmd_bufs
+        }
+    }
+}
+
+fn create_sampler(
+    options: epaint::textures::TextureOptions,
+    device: &wgpu::Device,
+) -> wgpu::Sampler {
+    let mag_filter = match options.magnification {
+        epaint::textures::TextureFilter::Nearest => wgpu::FilterMode::Nearest,
+        epaint::textures::TextureFilter::Linear => wgpu::FilterMode::Linear,
+    };
+    let min_filter = match options.minification {
+        epaint::textures::TextureFilter::Nearest => wgpu::FilterMode::Nearest,
+        epaint::textures::TextureFilter::Linear => wgpu::FilterMode::Linear,
+    };
+    device.create_sampler(&wgpu::SamplerDescriptor {
+        label: Some(&format!(
+            "egui sampler (mag: {:?}, min {:?})",
+            mag_filter, min_filter
+        )),
+        mag_filter,
+        min_filter,
+        ..Default::default()
+    })
+}
+
+fn create_vertex_buffer(device: &wgpu::Device, size: u64) -> wgpu::Buffer {
+    crate::profile_function!();
+    device.create_buffer(&wgpu::BufferDescriptor {
+        label: Some("egui_vertex_buffer"),
+        usage: wgpu::BufferUsages::VERTEX | wgpu::BufferUsages::COPY_DST,
+        size,
+        mapped_at_creation: false,
+    })
+}
+
+fn create_index_buffer(device: &wgpu::Device, size: u64) -> wgpu::Buffer {
+    crate::profile_function!();
+    device.create_buffer(&wgpu::BufferDescriptor {
+        label: Some("egui_index_buffer"),
+        usage: wgpu::BufferUsages::INDEX | wgpu::BufferUsages::COPY_DST,
+        size,
+        mapped_at_creation: false,
+    })
+}
+
+/// A Rect in physical pixel space, used for setting clipping rectangles.
+struct ScissorRect {
+    x: u32,
+    y: u32,
+    width: u32,
+    height: u32,
+}
+
+impl ScissorRect {
+    fn new(clip_rect: &epaint::Rect, pixels_per_point: f32, target_size: [u32; 2]) -> Self {
+        // Transform clip rect to physical pixels:
+        let clip_min_x = pixels_per_point * clip_rect.min.x;
+        let clip_min_y = pixels_per_point * clip_rect.min.y;
+        let clip_max_x = pixels_per_point * clip_rect.max.x;
+        let clip_max_y = pixels_per_point * clip_rect.max.y;
+
+        // Round to integer:
+        let clip_min_x = clip_min_x.round() as u32;
+        let clip_min_y = clip_min_y.round() as u32;
+        let clip_max_x = clip_max_x.round() as u32;
+        let clip_max_y = clip_max_y.round() as u32;
+
+        // Clamp:
+        let clip_min_x = clip_min_x.clamp(0, target_size[0]);
+        let clip_min_y = clip_min_y.clamp(0, target_size[1]);
+        let clip_max_x = clip_max_x.clamp(clip_min_x, target_size[0]);
+        let clip_max_y = clip_max_y.clamp(clip_min_y, target_size[1]);
+
+        Self {
+            x: clip_min_x,
+            y: clip_min_y,
+            width: clip_max_x - clip_min_x,
+            height: clip_max_y - clip_min_y,
+        }
+    }
+}
+
+#[test]
+fn renderer_impl_send_sync() {
+    fn assert_send_sync<T: Send + Sync>() {}
+    assert_send_sync::<Renderer>();
+}

egui/crates/egui-wgpu/src/winit.rs

@@ -0,0 +1,630 @@
+use std::sync::Arc;
+
+use epaint::{self, mutex::RwLock};
+
+use tracing::error;
+
+use crate::{renderer, RenderState, Renderer, SurfaceErrorAction, WgpuConfiguration};
+
+struct SurfaceState {
+    surface: wgpu::Surface,
+    alpha_mode: wgpu::CompositeAlphaMode,
+    width: u32,
+    height: u32,
+}
+
+/// A texture and a buffer for reading the rendered frame back to the cpu.
+/// The texture is required since [`wgpu::TextureUsages::COPY_DST`] is not an allowed
+/// flag for the surface texture on all platforms. This means that anytime we want to
+/// capture the frame, we first render it to this texture, and then we can copy it to
+/// both the surface texture and the buffer, from where we can pull it back to the cpu.
+struct CaptureState {
+    texture: wgpu::Texture,
+    buffer: wgpu::Buffer,
+    padding: BufferPadding,
+}
+
+impl CaptureState {
+    fn new(device: &Arc<wgpu::Device>, surface_texture: &wgpu::Texture) -> Self {
+        let texture = device.create_texture(&wgpu::TextureDescriptor {
+            label: Some("egui_screen_capture_texture"),
+            size: surface_texture.size(),
+            mip_level_count: surface_texture.mip_level_count(),
+            sample_count: surface_texture.sample_count(),
+            dimension: surface_texture.dimension(),
+            format: surface_texture.format(),
+            usage: wgpu::TextureUsages::RENDER_ATTACHMENT | wgpu::TextureUsages::COPY_SRC,
+            view_formats: &[],
+        });
+
+        let padding = BufferPadding::new(surface_texture.width());
+
+        let buffer = device.create_buffer(&wgpu::BufferDescriptor {
+            label: Some("egui_screen_capture_buffer"),
+            size: (padding.padded_bytes_per_row * texture.height()) as u64,
+            usage: wgpu::BufferUsages::COPY_DST | wgpu::BufferUsages::MAP_READ,
+            mapped_at_creation: false,
+        });
+
+        Self {
+            texture,
+            buffer,
+            padding,
+        }
+    }
+}
+
+struct BufferPadding {
+    unpadded_bytes_per_row: u32,
+    padded_bytes_per_row: u32,
+}
+
+impl BufferPadding {
+    fn new(width: u32) -> Self {
+        let bytes_per_pixel = std::mem::size_of::<u32>() as u32;
+        let unpadded_bytes_per_row = width * bytes_per_pixel;
+        let padded_bytes_per_row =
+            wgpu::util::align_to(unpadded_bytes_per_row, wgpu::COPY_BYTES_PER_ROW_ALIGNMENT);
+        Self {
+            unpadded_bytes_per_row,
+            padded_bytes_per_row,
+        }
+    }
+}
+
+/// Everything you need to paint egui with [`wgpu`] on [`winit`].
+///
+/// Alternatively you can use [`crate::renderer`] directly.
+pub struct Painter {
+    configuration: WgpuConfiguration,
+    msaa_samples: u32,
+    support_transparent_backbuffer: bool,
+    depth_format: Option<wgpu::TextureFormat>,
+    depth_texture_view: Option<wgpu::TextureView>,
+    msaa_texture_view: Option<wgpu::TextureView>,
+    screen_capture_state: Option<CaptureState>,
+
+    instance: wgpu::Instance,
+    adapter: Option<wgpu::Adapter>,
+    render_state: Option<RenderState>,
+    surface_state: Option<SurfaceState>,
+}
+
+impl Painter {
+    /// Manages [`wgpu`] state, including surface state, required to render egui.
+    ///
+    /// Only the [`wgpu::Instance`] is initialized here. Device selection and the initialization
+    /// of render + surface state is deferred until the painter is given its first window target
+    /// via [`set_window()`](Self::set_window). (Ensuring that a device that's compatible with the
+    /// native window is chosen)
+    ///
+    /// Before calling [`paint_and_update_textures()`](Self::paint_and_update_textures) a
+    /// [`wgpu::Surface`] must be initialized (and corresponding render state) by calling
+    /// [`set_window()`](Self::set_window) once you have
+    /// a [`winit::window::Window`] with a valid `.raw_window_handle()`
+    /// associated.
+    pub fn new(
+        configuration: WgpuConfiguration,
+        msaa_samples: u32,
+        depth_bits: u8,
+        support_transparent_backbuffer: bool,
+    ) -> Self {
+        let instance = wgpu::Instance::new(wgpu::InstanceDescriptor {
+            backends: configuration.backends,
+            dx12_shader_compiler: Default::default(), //
+        });
+
+        Self {
+            configuration,
+            msaa_samples,
+            support_transparent_backbuffer,
+            depth_format: (depth_bits > 0).then_some(wgpu::TextureFormat::Depth32Float),
+            depth_texture_view: None,
+            screen_capture_state: None,
+
+            instance,
+            adapter: None,
+            render_state: None,
+            surface_state: None,
+            msaa_texture_view: None,
+        }
+    }
+
+    /// Get the [`RenderState`].
+    ///
+    /// Will return [`None`] if the render state has not been initialized yet.
+    pub fn render_state(&self) -> Option<RenderState> {
+        self.render_state.clone()
+    }
+
+    async fn init_render_state(
+        &self,
+        adapter: &wgpu::Adapter,
+        target_format: wgpu::TextureFormat,
+    ) -> Result<RenderState, wgpu::RequestDeviceError> {
+        adapter
+            .request_device(&self.configuration.device_descriptor, None)
+            .await
+            .map(|(device, queue)| {
+                let renderer =
+                    Renderer::new(&device, target_format, self.depth_format, self.msaa_samples);
+                RenderState {
+                    device: Arc::new(device),
+                    queue: Arc::new(queue),
+                    target_format,
+                    renderer: Arc::new(RwLock::new(renderer)),
+                }
+            })
+    }
+
+    // We want to defer the initialization of our render state until we have a surface
+    // so we can take its format into account.
+    //
+    // After we've initialized our render state once though we expect all future surfaces
+    // will have the same format and so this render state will remain valid.
+    async fn ensure_render_state_for_surface(
+        &mut self,
+        surface: &wgpu::Surface,
+    ) -> Result<(), wgpu::RequestDeviceError> {
+        if self.adapter.is_none() {
+            self.adapter = self
+                .instance
+                .request_adapter(&wgpu::RequestAdapterOptions {
+                    power_preference: self.configuration.power_preference,
+                    compatible_surface: Some(surface),
+                    force_fallback_adapter: false,
+                })
+                .await;
+        }
+        if self.render_state.is_none() {
+            match &self.adapter {
+                Some(adapter) => {
+                    let swapchain_format = crate::preferred_framebuffer_format(
+                        &surface.get_capabilities(adapter).formats,
+                    );
+                    let rs = self.init_render_state(adapter, swapchain_format).await?;
+                    self.render_state = Some(rs);
+                }
+                None => return Err(wgpu::RequestDeviceError {}),
+            }
+        }
+        Ok(())
+    }
+
+    fn configure_surface(
+        surface_state: &SurfaceState,
+        render_state: &RenderState,
+        present_mode: wgpu::PresentMode,
+    ) {
+        surface_state.surface.configure(
+            &render_state.device,
+            &wgpu::SurfaceConfiguration {
+                usage: wgpu::TextureUsages::RENDER_ATTACHMENT | wgpu::TextureUsages::COPY_DST,
+                format: render_state.target_format,
+                width: surface_state.width,
+                height: surface_state.height,
+                present_mode,
+                alpha_mode: surface_state.alpha_mode,
+                view_formats: vec![render_state.target_format],
+            },
+        );
+    }
+
+    /// Updates (or clears) the [`winit::window::Window`] associated with the [`Painter`]
+    ///
+    /// This creates a [`wgpu::Surface`] for the given Window (as well as initializing render
+    /// state if needed) that is used for egui rendering.
+    ///
+    /// This must be called before trying to render via
+    /// [`paint_and_update_textures`](Self::paint_and_update_textures)
+    ///
+    /// # Portability
+    ///
+    /// _In particular it's important to note that on Android a it's only possible to create
+    /// a window surface between `Resumed` and `Paused` lifecycle events, and Winit will panic on
+    /// attempts to query the raw window handle while paused._
+    ///
+    /// On Android [`set_window`](Self::set_window) should be called with `Some(window)` for each
+    /// `Resumed` event and `None` for each `Paused` event. Currently, on all other platforms
+    /// [`set_window`](Self::set_window) may be called with `Some(window)` as soon as you have a
+    /// valid [`winit::window::Window`].
+    ///
+    /// # Safety
+    ///
+    /// The raw Window handle associated with the given `window` must be a valid object to create a
+    /// surface upon and must remain valid for the lifetime of the created surface. (The surface may
+    /// be cleared by passing `None`).
+    ///
+    /// # Errors
+    /// If the provided wgpu configuration does not match an available device.
+    pub async unsafe fn set_window(
+        &mut self,
+        window: Option<&winit::window::Window>,
+    ) -> Result<(), crate::WgpuError> {
+        match window {
+            Some(window) => {
+                let surface = self.instance.create_surface(&window)?;
+
+                self.ensure_render_state_for_surface(&surface).await?;
+
+                let alpha_mode = if self.support_transparent_backbuffer {
+                    let supported_alpha_modes = surface
+                        .get_capabilities(self.adapter.as_ref().unwrap())
+                        .alpha_modes;
+
+                    // Prefer pre multiplied over post multiplied!
+                    if supported_alpha_modes.contains(&wgpu::CompositeAlphaMode::PreMultiplied) {
+                        wgpu::CompositeAlphaMode::PreMultiplied
+                    } else if supported_alpha_modes
+                        .contains(&wgpu::CompositeAlphaMode::PostMultiplied)
+                    {
+                        wgpu::CompositeAlphaMode::PostMultiplied
+                    } else {
+                        tracing::warn!("Transparent window was requested, but the active wgpu surface does not support a `CompositeAlphaMode` with transparency.");
+                        wgpu::CompositeAlphaMode::Auto
+                    }
+                } else {
+                    wgpu::CompositeAlphaMode::Auto
+                };
+
+                let size = window.inner_size();
+                self.surface_state = Some(SurfaceState {
+                    surface,
+                    width: size.width,
+                    height: size.height,
+                    alpha_mode,
+                });
+                self.resize_and_generate_depth_texture_view_and_msaa_view(size.width, size.height);
+            }
+            None => {
+                self.surface_state = None;
+            }
+        }
+        Ok(())
+    }
+
+    /// Returns the maximum texture dimension supported if known
+    ///
+    /// This API will only return a known dimension after `set_window()` has been called
+    /// at least once, since the underlying device and render state are initialized lazily
+    /// once we have a window (that may determine the choice of adapter/device).
+    pub fn max_texture_side(&self) -> Option<usize> {
+        self.render_state
+            .as_ref()
+            .map(|rs| rs.device.limits().max_texture_dimension_2d as usize)
+    }
+
+    fn resize_and_generate_depth_texture_view_and_msaa_view(
+        &mut self,
+        width_in_pixels: u32,
+        height_in_pixels: u32,
+    ) {
+        let render_state = self.render_state.as_ref().unwrap();
+        let surface_state = self.surface_state.as_mut().unwrap();
+
+        surface_state.width = width_in_pixels;
+        surface_state.height = height_in_pixels;
+
+        Self::configure_surface(surface_state, render_state, self.configuration.present_mode);
+
+        self.depth_texture_view = self.depth_format.map(|depth_format| {
+            render_state
+                .device
+                .create_texture(&wgpu::TextureDescriptor {
+                    label: Some("egui_depth_texture"),
+                    size: wgpu::Extent3d {
+                        width: width_in_pixels,
+                        height: height_in_pixels,
+                        depth_or_array_layers: 1,
+                    },
+                    mip_level_count: 1,
+                    sample_count: 1,
+                    dimension: wgpu::TextureDimension::D2,
+                    format: depth_format,
+                    usage: wgpu::TextureUsages::RENDER_ATTACHMENT
+                        | wgpu::TextureUsages::TEXTURE_BINDING,
+                    view_formats: &[depth_format],
+                })
+                .create_view(&wgpu::TextureViewDescriptor::default())
+        });
+
+        self.msaa_texture_view = (self.msaa_samples > 1)
+            .then_some(self.render_state.as_ref())
+            .flatten()
+            .map(|render_state| {
+                let texture_format = render_state.target_format;
+                render_state
+                    .device
+                    .create_texture(&wgpu::TextureDescriptor {
+                        label: Some("egui_msaa_texture"),
+                        size: wgpu::Extent3d {
+                            width: width_in_pixels,
+                            height: height_in_pixels,
+                            depth_or_array_layers: 1,
+                        },
+                        mip_level_count: 1,
+                        sample_count: self.msaa_samples,
+                        dimension: wgpu::TextureDimension::D2,
+                        format: texture_format,
+                        usage: wgpu::TextureUsages::RENDER_ATTACHMENT,
+                        view_formats: &[texture_format],
+                    })
+                    .create_view(&wgpu::TextureViewDescriptor::default())
+            });
+    }
+
+    pub fn on_window_resized(&mut self, width_in_pixels: u32, height_in_pixels: u32) {
+        if self.surface_state.is_some() {
+            self.resize_and_generate_depth_texture_view_and_msaa_view(
+                width_in_pixels,
+                height_in_pixels,
+            );
+        } else {
+            error!("Ignoring window resize notification with no surface created via Painter::set_window()");
+        }
+    }
+
+    // CaptureState only needs to be updated when the size of the two textures don't match and we want to
+    // capture a frame
+    fn update_capture_state(
+        screen_capture_state: &mut Option<CaptureState>,
+        surface_texture: &wgpu::SurfaceTexture,
+        render_state: &RenderState,
+    ) {
+        let surface_texture = &surface_texture.texture;
+        match screen_capture_state {
+            Some(capture_state) => {
+                if capture_state.texture.size() != surface_texture.size() {
+                    *capture_state = CaptureState::new(&render_state.device, surface_texture);
+                }
+            }
+            None => {
+                *screen_capture_state =
+                    Some(CaptureState::new(&render_state.device, surface_texture));
+            }
+        }
+    }
+
+    // Handles copying from the CaptureState texture to the surface texture and the cpu
+    fn read_screen_rgba(
+        screen_capture_state: &CaptureState,
+        render_state: &RenderState,
+        output_frame: &wgpu::SurfaceTexture,
+    ) -> Option<epaint::ColorImage> {
+        let CaptureState {
+            texture: tex,
+            buffer,
+            padding,
+        } = screen_capture_state;
+
+        let device = &render_state.device;
+        let queue = &render_state.queue;
+
+        let tex_extent = tex.size();
+
+        let mut encoder = device.create_command_encoder(&Default::default());
+        encoder.copy_texture_to_buffer(
+            tex.as_image_copy(),
+            wgpu::ImageCopyBuffer {
+                buffer,
+                layout: wgpu::ImageDataLayout {
+                    offset: 0,
+                    bytes_per_row: Some(std::num::NonZeroU32::new(padding.padded_bytes_per_row)?),
+                    rows_per_image: None,
+                },
+            },
+            tex_extent,
+        );
+
+        encoder.copy_texture_to_texture(
+            tex.as_image_copy(),
+            output_frame.texture.as_image_copy(),
+            tex.size(),
+        );
+
+        let id = queue.submit(Some(encoder.finish()));
+        let buffer_slice = buffer.slice(..);
+        let (sender, receiver) = std::sync::mpsc::channel();
+        buffer_slice.map_async(wgpu::MapMode::Read, move |v| {
+            drop(sender.send(v));
+        });
+        device.poll(wgpu::Maintain::WaitForSubmissionIndex(id));
+        receiver.recv().ok()?.ok()?;
+
+        let to_rgba = match tex.format() {
+            wgpu::TextureFormat::Rgba8Unorm => [0, 1, 2, 3],
+            wgpu::TextureFormat::Bgra8Unorm => [2, 1, 0, 3],
+            _ => {
+                tracing::error!("Screen can't be captured unless the surface format is Rgba8Unorm or Bgra8Unorm. Current surface format is {:?}", tex.format());
+                return None;
+            }
+        };
+
+        let mut pixels = Vec::with_capacity((tex.width() * tex.height()) as usize);
+        for padded_row in buffer_slice
+            .get_mapped_range()
+            .chunks(padding.padded_bytes_per_row as usize)
+        {
+            let row = &padded_row[..padding.unpadded_bytes_per_row as usize];
+            for color in row.chunks(4) {
+                pixels.push(epaint::Color32::from_rgba_premultiplied(
+                    color[to_rgba[0]],
+                    color[to_rgba[1]],
+                    color[to_rgba[2]],
+                    color[to_rgba[3]],
+                ));
+            }
+        }
+        buffer.unmap();
+
+        Some(epaint::ColorImage {
+            size: [tex.width() as usize, tex.height() as usize],
+            pixels,
+        })
+    }
+
+    // Returns a vector with the frame's pixel data if it was requested.
+    pub fn paint_and_update_textures(
+        &mut self,
+        pixels_per_point: f32,
+        clear_color: [f32; 4],
+        clipped_primitives: &[epaint::ClippedPrimitive],
+        textures_delta: &epaint::textures::TexturesDelta,
+        capture: bool,
+    ) -> Option<epaint::ColorImage> {
+        crate::profile_function!();
+
+        let render_state = self.render_state.as_mut()?;
+        let surface_state = self.surface_state.as_ref()?;
+
+        let output_frame = {
+            crate::profile_scope!("get_current_texture");
+            // This is what vsync-waiting happens, at least on Mac.
+            surface_state.surface.get_current_texture()
+        };
+
+        let output_frame = match output_frame {
+            Ok(frame) => frame,
+            #[allow(clippy::single_match_else)]
+            Err(e) => match (*self.configuration.on_surface_error)(e) {
+                SurfaceErrorAction::RecreateSurface => {
+                    Self::configure_surface(
+                        surface_state,
+                        render_state,
+                        self.configuration.present_mode,
+                    );
+                    return None;
+                }
+                SurfaceErrorAction::SkipFrame => {
+                    return None;
+                }
+            },
+        };
+
+        let mut encoder =
+            render_state
+                .device
+                .create_command_encoder(&wgpu::CommandEncoderDescriptor {
+                    label: Some("encoder"),
+                });
+
+        // Upload all resources for the GPU.
+        let screen_descriptor = renderer::ScreenDescriptor {
+            size_in_pixels: [surface_state.width, surface_state.height],
+            pixels_per_point,
+        };
+
+        let user_cmd_bufs = {
+            let mut renderer = render_state.renderer.write();
+            for (id, image_delta) in &textures_delta.set {
+                renderer.update_texture(
+                    &render_state.device,
+                    &render_state.queue,
+                    *id,
+                    image_delta,
+                );
+            }
+
+            renderer.update_buffers(
+                &render_state.device,
+                &render_state.queue,
+                &mut encoder,
+                clipped_primitives,
+                &screen_descriptor,
+            )
+        };
+
+        {
+            let renderer = render_state.renderer.read();
+            let frame_view = if capture {
+                Self::update_capture_state(
+                    &mut self.screen_capture_state,
+                    &output_frame,
+                    render_state,
+                );
+                self.screen_capture_state
+                    .as_ref()?
+                    .texture
+                    .create_view(&wgpu::TextureViewDescriptor::default())
+            } else {
+                output_frame
+                    .texture
+                    .create_view(&wgpu::TextureViewDescriptor::default())
+            };
+
+            let (view, resolve_target) = (self.msaa_samples > 1)
+                .then_some(self.msaa_texture_view.as_ref())
+                .flatten()
+                .map_or((&frame_view, None), |texture_view| {
+                    (texture_view, Some(&frame_view))
+                });
+
+            let mut render_pass = encoder.begin_render_pass(&wgpu::RenderPassDescriptor {
+                color_attachments: &[Some(wgpu::RenderPassColorAttachment {
+                    view,
+                    resolve_target,
+                    ops: wgpu::Operations {
+                        load: wgpu::LoadOp::Clear(wgpu::Color {
+                            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,
+                    },
+                })],
+                depth_stencil_attachment: self.depth_texture_view.as_ref().map(|view| {
+                    wgpu::RenderPassDepthStencilAttachment {
+                        view,
+                        depth_ops: Some(wgpu::Operations {
+                            load: wgpu::LoadOp::Clear(1.0),
+                            store: true,
+                        }),
+                        stencil_ops: None,
+                    }
+                }),
+                label: Some("egui_render"),
+            });
+
+            renderer.render(&mut render_pass, clipped_primitives, &screen_descriptor);
+        }
+
+        {
+            let mut renderer = render_state.renderer.write();
+            for id in &textures_delta.free {
+                renderer.free_texture(id);
+            }
+        }
+
+        let encoded = {
+            crate::profile_scope!("CommandEncoder::finish");
+            encoder.finish()
+        };
+
+        // Submit the commands: both the main buffer and user-defined ones.
+        {
+            crate::profile_scope!("Queue::submit");
+            render_state
+                .queue
+                .submit(user_cmd_bufs.into_iter().chain(std::iter::once(encoded)));
+        };
+
+        let screenshot = if capture {
+            let screen_capture_state = self.screen_capture_state.as_ref()?;
+            Self::read_screen_rgba(screen_capture_state, render_state, &output_frame)
+        } else {
+            None
+        };
+        // Redraw egui
+        {
+            crate::profile_scope!("present");
+            output_frame.present();
+        }
+        screenshot
+    }
+
+    #[allow(clippy::unused_self)]
+    pub fn destroy(&mut self) {
+        // TODO(emilk): something here?
+    }
+}