ribir_gpu 0.4.0-alpha.64

A non-intrusive declarative GUI framework, to build modern native/wasm cross-platform applications.
Documentation
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use std::{any::Any, cmp::Ordering, hash::Hash, ops::Range};

use guillotiere::euclid::SideOffsets2D;
use rayon::{prelude::ParallelIterator, slice::ParallelSlice};
use ribir_algo::Resource;
use ribir_painter::{
  ColorFormat, PaintPath, PaintingStyle, Path, PixelImage, StrokeOptions, Vertex, VertexBuffers,
};
use ribir_types::{DeviceRect, DeviceSize, Size, Transform, transform_to_device_rect};

use super::{
  Texture,
  atlas::{Atlas, AtlasConfig, AtlasDist},
};
use crate::GPUBackendImpl;
const TOLERANCE: f32 = 0.1_f32;
const PAR_CHUNKS_SIZE: usize = 64;

#[derive(Debug, Clone, Hash, PartialEq, Eq, PartialOrd, Ord, Copy)]
pub(super) enum TextureID {
  Alpha(usize),
  Rgba(usize),
  Bundle(usize),
}

#[derive(PartialEq, Clone)]
enum PathKey {
  Fill(Resource<dyn Any>),
  Stroke { resource: Resource<dyn Any>, options: StrokeOptions },
}

pub(super) struct TexturesMgr<T: Texture> {
  alpha_atlas: Atlas<PathKey, T>,
  rgba_atlas: Atlas<Resource<dyn Any>, T>,
  /// Similar to the `rgba_atlas`, this is used to allocate the target texture
  /// for drawing commands.
  ///
  /// We keep it separate from `rgba_atlas` because the backend may not permit a
  /// texture to be used both as a target and as a sampled resource in the same
  /// draw call.
  bundle_atlas: Atlas<Resource<dyn Any>, T>,
  tess_task: Vec<TessTask>,
  tess_task_buffer: VertexBuffers<()>,
}

struct TessTask {
  slice: TextureSlice,
  path: PaintPath,
  style: PaintingStyle,
  // transform to construct vertex
  transform: Transform,
  clip_rect: Option<DeviceRect>,
}

#[derive(Debug, Clone, Copy, PartialEq)]
pub(super) struct TextureSlice {
  pub(super) tex_id: TextureID,
  pub(super) rect: DeviceRect,
}

macro_rules! id_to_texture_mut {
  ($mgr:ident, $id:expr) => {
    match $id {
      TextureID::Alpha(id) => $mgr.alpha_atlas.get_texture_mut(id),
      TextureID::Rgba(id) => $mgr.rgba_atlas.get_texture_mut(id),
      TextureID::Bundle(id) => $mgr.bundle_atlas.get_texture_mut(id),
    }
  };
}

macro_rules! id_to_texture {
  ($mgr:ident, $id:expr) => {
    match $id {
      TextureID::Alpha(id) => $mgr.alpha_atlas.get_texture(id),
      TextureID::Rgba(id) => $mgr.rgba_atlas.get_texture(id),
      TextureID::Bundle(id) => $mgr.bundle_atlas.get_texture(id),
    }
  };
}

impl<T: Texture> TexturesMgr<T>
where
  T::Host: GPUBackendImpl<Texture = T>,
{
  pub(super) fn new(gpu_impl: &mut T::Host) -> Self {
    let limits = gpu_impl.limits();
    let max_size = limits.texture_size;

    Self {
      alpha_atlas: Atlas::new(
        AtlasConfig::new("Alpha atlas", max_size),
        ColorFormat::Alpha8,
        gpu_impl,
      ),
      rgba_atlas: Atlas::new(
        AtlasConfig::new("Rgba atlas", max_size),
        ColorFormat::Rgba8,
        gpu_impl,
      ),
      bundle_atlas: Atlas::new(
        AtlasConfig::new("Bundle atlas", max_size),
        ColorFormat::Rgba8,
        gpu_impl,
      ),
      tess_task: <_>::default(),
      tess_task_buffer: <_>::default(),
    }
  }

  /// Store an alpha path in texture and return the texture and a transform that
  /// can transform the mask to viewport
  pub(super) fn store_alpha_path(
    &mut self, path: &PaintPath, style: &PaintingStyle, matrix: &Transform, viewport: &DeviceRect,
    gpu: &mut T::Host,
  ) -> (TextureSlice, Transform) {
    let path_bounds = path.bounds(style.line_width());
    match path {
      PaintPath::Share(p) => {
        let resource = p.clone().into_any();
        let cache_scale: f32 = self.cache_scale(&path_bounds.size, matrix);
        let key = match style {
          PaintingStyle::Fill => PathKey::Fill(resource),
          PaintingStyle::Stroke(options) => PathKey::Stroke { resource, options: options.clone() },
        };

        let (slice, scale) = if let Some(h) = self.alpha_atlas.get(&key, cache_scale).copied() {
          let mask_slice = self.alpha_atlas_dist_to_tex_slice(&h.dist);
          (mask_slice, h.scale)
        } else {
          let scale_bounds = path_bounds.scale(cache_scale, cache_scale);
          let (dist, slice) =
            self.alpha_allocate(scale_bounds.round_out().size.to_i32().cast_unit(), gpu);
          let _ = self.alpha_atlas.cache(key, cache_scale, dist);
          let offset = slice.rect.origin.to_f32().cast_unit() - scale_bounds.origin;
          let transform = Transform::scale(cache_scale, cache_scale).then_translate(offset);
          self.tess_task.push(TessTask {
            slice,
            path: path.clone(),
            transform,
            clip_rect: None,
            style: style.clone(),
          });
          (slice, cache_scale)
        };

        let path_origin = path_bounds.origin * scale;
        let slice_origin = slice.rect.origin.to_vector().to_f32();
        // back to slice origin
        let matrix = Transform::translation(-slice_origin.x, -slice_origin.y)
          // move to cached path axis.
          .then_translate(path_origin.to_vector().cast_unit())
          // scale back to path axis.
          .then_scale(1. / scale, 1. / scale)
          // apply path transform matrix to view.
          .then(matrix);

        (slice.expand_for_paste(), matrix)
      }
      PaintPath::Own(_) => {
        let paint_bounds = transform_to_device_rect(&path_bounds, matrix);
        let alloc_size = size_expand_blank(paint_bounds.size);

        let (visual_rect, clip_rect) = if self.alpha_atlas.is_good_size_to_alloc(alloc_size) {
          (paint_bounds, None)
        } else {
          // We intersect the path bounds with the viewport to reduce the number of pixels
          // drawn for large paths.
          let visual_rect = paint_bounds.intersection(viewport).unwrap();
          (visual_rect, Some(visual_rect))
        };

        let (_, slice) = self.alpha_allocate(visual_rect.size, gpu);
        let offset = (slice.rect.origin - visual_rect.origin)
          .to_f32()
          .cast_unit();
        let ts = matrix.then_translate(offset);
        let task =
          TessTask { slice, transform: ts, path: path.clone(), style: style.clone(), clip_rect };
        self.tess_task.push(task);

        let offset = (visual_rect.origin - slice.rect.origin).to_f32();
        (slice.expand_for_paste(), Transform::translation(offset.x, offset.y))
      }
      PaintPath::PixelImage(img) => {
        let key = PathKey::Fill(img.clone().into_any());
        let (slice, _scale) = if let Some(h) = self.alpha_atlas.get(&key, 1.).copied() {
          let mask_slice = self.alpha_atlas_dist_to_tex_slice(&h.dist);
          (mask_slice, h.scale)
        } else {
          let (dist, slice) = self.alpha_allocate(img.size(), gpu);
          let _ = self.alpha_atlas.cache(key, 1., dist);

          let texture = self.alpha_atlas.get_texture_mut(dist.tex_id());
          texture.write_data(&slice.rect, img.pixel_bytes(), gpu);

          (slice, 1.0)
        };

        let slice_origin = slice.rect.origin.to_vector().to_f32();
        let ts = Transform::translation(-slice_origin.x, -slice_origin.y).then(matrix);

        (slice.expand_for_paste(), ts)
      }
    }
  }

  pub(super) fn store_image(
    &mut self, img: &Resource<PixelImage>, gpu: &mut T::Host,
  ) -> TextureSlice {
    match img.color_format() {
      ColorFormat::Rgba8 => {
        let blank_side = SideOffsets2D::new_all_same(RGBA_BLEED_EDGE);
        let atlas = &mut self.rgba_atlas;
        let h = atlas.get_or_cache(
          img.clone().into_any(),
          1.,
          size_expand_edge(img.size(), RGBA_BLEED_EDGE),
          gpu,
          // Mirror the outermost texels into a 1px border so linear sampling
          // doesn't blend color emoji edges with transparent atlas pixels.
          |rect, texture, gpu| texture.write_data(rect, &rgba_pixels_with_bleed(img), gpu),
        );
        TextureSlice {
          tex_id: TextureID::Rgba(h.tex_id()),
          rect: h.tex_rect(atlas).inner_rect(blank_side),
        }
      }
      ColorFormat::Alpha8 => {
        let key = PathKey::Fill(img.clone().into_any());
        let atlas = &mut self.alpha_atlas;
        let h = atlas.get_or_cache(key, 1., img.size(), gpu, |rect, texture, gpu| {
          texture.write_data(rect, img.pixel_bytes(), gpu)
        });
        TextureSlice { tex_id: TextureID::Alpha(h.tex_id()), rect: h.tex_rect(atlas) }
      }
    }
  }

  pub(super) fn store_commands(
    &mut self, size: DeviceSize, target: Resource<dyn Any>, scale: f32, gpu: &mut T::Host,
    init: impl FnOnce(&DeviceRect, &mut T, &mut T::Host),
  ) -> (f32, TextureSlice) {
    if let Some(h) = self.bundle_atlas.get(&target, scale).copied() {
      return (
        h.scale,
        TextureSlice {
          tex_id: TextureID::Bundle(h.tex_id()),
          rect: h.tex_rect(&self.bundle_atlas),
        },
      );
    }

    let bundle_dist = self.bundle_atlas.allocate(size, gpu);
    let bundle_rect = bundle_dist.tex_rect(&self.bundle_atlas);
    let mut temp_tex = gpu.new_texture(size, ColorFormat::Rgba8);
    let temp_rect = DeviceRect::from_size(size);
    init(&temp_rect, &mut temp_tex, gpu);

    let bundle_tex = self
      .bundle_atlas
      .get_texture_mut(bundle_dist.tex_id());

    gpu.copy_texture_from_texture(bundle_tex, bundle_rect.min(), &temp_tex, &temp_rect);

    let h = self
      .bundle_atlas
      .cache(target, scale, bundle_dist);
    (
      h.scale,
      TextureSlice { tex_id: TextureID::Bundle(h.tex_id()), rect: h.tex_rect(&self.bundle_atlas) },
    )
  }

  pub(super) fn texture(&self, tex_id: TextureID) -> &T { id_to_texture!(self, tex_id) }

  fn alpha_allocate(
    &mut self, mut size: DeviceSize, gpu: &mut T::Host,
  ) -> (AtlasDist, TextureSlice) {
    size = size_expand_blank(size);
    // Allocate with a 2-pixel blank edge to ensure that neighboring slices do not
    // affect the current slice.
    let dist = self.alpha_atlas.allocate(size, gpu);

    (dist, self.alpha_atlas_dist_to_tex_slice(&dist))
  }

  fn alpha_atlas_dist_to_tex_slice(&self, dist: &AtlasDist) -> TextureSlice {
    let blank_side = SideOffsets2D::new_all_same(ALPHA_BLANK_EDGE);
    let rect = dist.tex_rect(&self.alpha_atlas);

    TextureSlice { tex_id: TextureID::Alpha(dist.tex_id()), rect: rect.inner_rect(blank_side) }
  }

  pub(super) fn cache_scale(&self, size: &Size, matrix: &Transform) -> f32 {
    let Transform { m11, m12, m21, m22, .. } = matrix;
    let scale = (m11.abs() + m12.abs()).max(m21.abs() + m22.abs());
    let dis = size.width.max(size.height);
    if dis * scale < 32. {
      // If the path is too small, set a minimum tessellation size of 32 pixels.
      32. / dis
    } else {
      // 2 * BLANK_EDGE is the blank edge for each side.
      let max_size = size_shrink_blank(self.alpha_atlas.max_size()).to_f32();
      let max_scale = (max_size.width / size.width).min(max_size.width / size.height);
      scale.min(max_scale)
    }
  }

  fn tessellate(
    path: &Path, style: &PaintingStyle, ts: &Transform, slice_size: &DeviceSize,
    buffer: &mut VertexBuffers<()>,
  ) -> Range<u32> {
    let start = buffer.indices.len() as u32;
    let path_size = path.bounds(style.line_width()).size;
    let slice_size = slice_size.to_f32();
    let scale = (slice_size.width / path_size.width).max(slice_size.height / path_size.height);
    let tolerance = TOLERANCE / scale;
    let vertex_ctor = |pos| {
      let pos = ts.transform_point(pos);
      Vertex::new([pos.x, pos.y], ())
    };
    match style {
      PaintingStyle::Fill => path.fill_tessellate(tolerance, buffer, vertex_ctor),
      PaintingStyle::Stroke(options) => {
        path.stroke_tessellate(tolerance, options.clone(), buffer, vertex_ctor)
      }
    }

    start..buffer.indices.len() as u32
  }

  pub(crate) fn draw_alpha_textures<G: GPUBackendImpl<Texture = T>>(&mut self, gpu_impl: &mut G)
  where
    T: Texture<Host = G>,
  {
    if self.tess_task.is_empty() {
      return;
    }

    self.tess_task.sort_by(|a, b| {
      let a_clip = a.clip_rect.is_some();
      let b_clip = b.clip_rect.is_some();
      if a_clip == b_clip {
        a.slice.tex_id.cmp(&b.slice.tex_id)
      } else if a_clip {
        Ordering::Less
      } else {
        Ordering::Greater
      }
    });

    let mut draw_indices = Vec::with_capacity(self.tess_task.len());
    if self.tess_task.len() < PAR_CHUNKS_SIZE {
      for f in self.tess_task.iter() {
        let TessTask { slice, path, clip_rect, transform, style } = f;
        let rg =
          Self::tessellate(path, style, transform, &slice.rect.size, &mut self.tess_task_buffer);
        draw_indices.push((slice.tex_id, rg, clip_rect));
      }
    } else {
      let mut tasks = Vec::with_capacity(self.tess_task.len());
      for f in self.tess_task.iter() {
        let TessTask { slice, path, clip_rect, transform, style } = f;
        tasks.push((slice, style, transform, path, clip_rect));
      }

      let par_tess_res = tasks
        .par_chunks(PAR_CHUNKS_SIZE)
        .map(|tasks| {
          let mut buffer = VertexBuffers::default();
          let mut indices = Vec::with_capacity(tasks.len());
          for (slice, style, ts, path, clip_rect) in tasks.iter() {
            let rg = Self::tessellate(path, style, ts, &slice.rect.size, &mut buffer);
            indices.push((slice.tex_id, rg, *clip_rect));
          }
          (indices, buffer)
        })
        .collect::<Vec<_>>();

      par_tess_res
        .into_iter()
        .for_each(|(indices, buffer)| {
          let offset = self.tess_task_buffer.indices.len() as u32;
          draw_indices.extend(indices.into_iter().map(|(id, mut rg, clip)| {
            rg.start += offset;
            rg.end += offset;
            (id, rg, clip)
          }));
          extend_buffer(&mut self.tess_task_buffer, buffer);
        })
    };

    gpu_impl.load_alpha_vertices(&self.tess_task_buffer);

    let mut idx = 0;
    loop {
      if idx >= draw_indices.len() {
        break;
      }

      let (tex_id, rg, Some(clip_rect)) = &draw_indices[idx] else {
        break;
      };
      let texture = id_to_texture_mut!(self, *tex_id);
      let size_offset = gpu_impl.load_alpha_size(texture.size());
      gpu_impl.draw_alpha_triangles_with_scissor(rg, texture, *clip_rect, size_offset);
      idx += 1;
    }

    loop {
      if idx >= draw_indices.len() {
        break;
      }
      let (tex_id, rg, None) = &draw_indices[idx] else {
        unreachable!();
      };
      let next = draw_indices[idx..]
        .iter()
        .position(|(next, _, _)| tex_id != next);

      let indices = if let Some(mut next) = next {
        next += idx;
        idx = next;
        let (_, end, _) = &draw_indices[next];
        rg.start..end.start
      } else {
        idx = draw_indices.len();
        rg.start..self.tess_task_buffer.indices.len() as u32
      };

      let texture = id_to_texture_mut!(self, *tex_id);
      let size_offset = gpu_impl.load_alpha_size(texture.size());
      gpu_impl.draw_alpha_triangles(&indices, texture, size_offset);
    }

    self.tess_task.clear();
    self.tess_task_buffer.vertices.clear();
    self.tess_task_buffer.indices.clear();
  }

  pub(crate) fn end_frame(&mut self, gpu_impl: &mut T::Host) -> bool {
    let mut clear_areas = vec![];
    self.alpha_atlas.end_frame_with(|rect| {
      clear_areas.push(rect);
    });
    self.rgba_atlas.end_frame();
    self.bundle_atlas.end_frame();

    if clear_areas.is_empty() {
      false
    } else {
      let texture = self.alpha_atlas.get_texture_mut(0);
      texture.clear_areas(&clear_areas, gpu_impl);
      true
    }
  }
}

fn extend_buffer<V>(dist: &mut VertexBuffers<V>, from: VertexBuffers<V>) {
  if dist.vertices.is_empty() {
    dist.vertices.extend(from.vertices);
    dist.indices.extend(from.indices);
  } else {
    let offset = dist.vertices.len() as u32;
    dist
      .indices
      .extend(from.indices.into_iter().map(|i| offset + i));
    dist.vertices.extend(from.vertices);
  }
}

const ALPHA_BLANK_EDGE: i32 = 2;
const RGBA_BLEED_EDGE: i32 = 1;

fn size_expand_edge(mut size: DeviceSize, edge: i32) -> DeviceSize {
  size.width += edge * 2;
  size.height += edge * 2;
  size
}

fn size_expand_blank(size: DeviceSize) -> DeviceSize { size_expand_edge(size, ALPHA_BLANK_EDGE) }

fn size_shrink_blank(mut size: DeviceSize) -> DeviceSize {
  size.width -= ALPHA_BLANK_EDGE * 2;
  size.height -= ALPHA_BLANK_EDGE * 2;
  size
}

fn rgba_pixels_with_bleed(img: &PixelImage) -> Vec<u8> {
  let width = img.width() as usize;
  let height = img.height() as usize;
  if width == 0 || height == 0 {
    return Vec::new();
  }

  let src = img.pixel_bytes();
  let edge = RGBA_BLEED_EDGE as usize;
  let padded_width = width + edge * 2;
  let padded_height = height + edge * 2;
  let stride = width * 4;
  let padded_stride = padded_width * 4;
  let mut padded = vec![0; padded_stride * padded_height];

  for y in 0..height {
    let src_row = &src[y * stride..(y + 1) * stride];
    let dst_offset = (y + edge) * padded_stride;
    let dst_row = &mut padded[dst_offset..dst_offset + padded_stride];
    dst_row[edge * 4..edge * 4 + stride].copy_from_slice(src_row);

    let first = &src_row[..4];
    for x in 0..edge {
      let offset = x * 4;
      dst_row[offset..offset + 4].copy_from_slice(first);
    }

    let last = &src_row[stride - 4..stride];
    for x in 0..edge {
      let offset = (edge + width + x) * 4;
      dst_row[offset..offset + 4].copy_from_slice(last);
    }
  }

  let first_row = padded[edge * padded_stride..(edge + 1) * padded_stride].to_vec();
  for y in 0..edge {
    let start = y * padded_stride;
    padded[start..start + padded_stride].copy_from_slice(&first_row);
  }

  let last_row_start = (edge + height - 1) * padded_stride;
  let last_row = padded[last_row_start..last_row_start + padded_stride].to_vec();
  for y in 0..edge {
    let start = (edge + height + y) * padded_stride;
    padded[start..start + padded_stride].copy_from_slice(&last_row);
  }

  padded
}

impl TextureSlice {
  pub fn expand_for_paste(mut self) -> TextureSlice {
    const EXPANDED_EDGE: i32 = 1;
    let blank_side = SideOffsets2D::new_all_same(EXPANDED_EDGE);
    self.rect = self.rect.outer_rect(blank_side);
    self
  }
}

impl Hash for PathKey {
  fn hash<H: std::hash::Hasher>(&self, state: &mut H) {
    match self {
      PathKey::Fill(path) => path.hash(state),
      PathKey::Stroke { resource: path, options } => {
        path.hash(state);
        let StrokeOptions { width, miter_limit, line_cap, line_join } = options;
        width.to_bits().hash(state);
        miter_limit.to_bits().hash(state);
        line_cap.hash(state);
        line_join.hash(state);
      }
    }
  }
}

impl Eq for PathKey {}

#[cfg(feature = "wgpu")]
#[cfg(test)]
pub mod tests {
  use std::borrow::Cow;

  use futures::executor::block_on;
  use ribir_painter::Color;
  use ribir_types::*;

  use super::*;
  use crate::{WgpuImpl, WgpuTexture};

  pub fn color_image(color: Color, width: u32, height: u32) -> Resource<PixelImage> {
    let data = std::iter::repeat_n(color.into_components(), width as usize * height as usize)
      .flatten()
      .collect::<Vec<_>>();

    let img = PixelImage::new(Cow::Owned(data), width, height, ColorFormat::Rgba8);
    Resource::new(img)
  }

  #[test]
  fn smoke_store_image() {
    let mut wgpu = block_on(WgpuImpl::headless());
    let mut mgr = TexturesMgr::new(&mut wgpu);

    let red_img = color_image(Color::RED, 32, 32);
    let red_rect = mgr.store_image(&red_img, &mut wgpu);

    assert_eq!(red_rect.rect.min().to_array(), [RGBA_BLEED_EDGE, RGBA_BLEED_EDGE]);

    // same image should have same position in atlas
    assert_eq!(red_rect, mgr.store_image(&red_img, &mut wgpu));
    color_img_check(&mgr, &red_rect, &mut wgpu, Color::RED);

    let yellow_img = color_image(Color::YELLOW, 64, 64);
    let yellow_rect = mgr.store_image(&yellow_img, &mut wgpu);

    // the color should keep after atlas rearrange
    color_img_check(&mgr, &red_rect, &mut wgpu, Color::RED);
    color_img_check(&mgr, &yellow_rect, &mut wgpu, Color::YELLOW);

    let extra_blue_img = color_image(Color::BLUE, 1024, 1024);
    let blue_rect = mgr.store_image(&extra_blue_img, &mut wgpu);

    color_img_check(&mgr, &blue_rect, &mut wgpu, Color::BLUE);
    color_img_check(&mgr, &red_rect, &mut wgpu, Color::RED);
    color_img_check(&mgr, &yellow_rect, &mut wgpu, Color::YELLOW);
  }

  fn color_img_check(
    mgr: &TexturesMgr<WgpuTexture>, rect: &TextureSlice, wgpu: &mut WgpuImpl, color: Color,
  ) {
    wgpu.begin_frame();
    let texture = mgr.texture(rect.tex_id);
    let img = texture.copy_as_image(&rect.rect, wgpu);
    wgpu.end_frame();

    let img = block_on(img).unwrap();
    assert!(
      img
        .pixel_bytes()
        .chunks(4)
        .all(|c| c == color.into_components())
    );
  }

  #[test]
  fn transform_path_share_cache() {
    let mut wgpu = block_on(WgpuImpl::headless());
    let mut mgr = TexturesMgr::<WgpuTexture>::new(&mut wgpu);

    let p = Resource::new(Path::rect(&rect(0., 0., 300., 300.)));
    let p = PaintPath::Share(p.clone());

    let viewport = rect(0, 0, 1024, 1024);
    let (slice1, ts1) = mgr.store_alpha_path(
      &p,
      &PaintingStyle::Fill,
      &Transform::scale(2., 2.),
      &viewport,
      &mut wgpu,
    );

    let (slice2, ts2) = mgr.store_alpha_path(
      &p,
      &PaintingStyle::Fill,
      &Transform::translation(100., 100.),
      &viewport,
      &mut wgpu,
    );
    assert_eq!(slice1, slice2);

    assert_eq!(ts1, Transform::new(1., 0., 0., 1., -2., -2.));
    assert_eq!(ts2, Transform::new(0.5, 0., 0., 0.5, 99., 99.));
  }

  #[test]
  fn fix_resource_address_conflict() {
    // because the next resource may allocate at same address of a deallocated
    // address.

    let mut wgpu = block_on(WgpuImpl::headless());
    let mut mgr = TexturesMgr::<WgpuTexture>::new(&mut wgpu);
    {
      let red_img = color_image(Color::RED, 32, 32);
      mgr.store_image(&red_img, &mut wgpu);
    }

    for _ in 0..10 {
      mgr.end_frame(&mut wgpu);
      let red_img = color_image(Color::RED, 32, 32).into_any();
      assert!(mgr.rgba_atlas.get(&red_img, 1.).is_none());
    }
  }

  #[test]
  fn rgba_images_store_edge_bleed_pixels() {
    let mut wgpu = block_on(WgpuImpl::headless());
    let mut mgr = TexturesMgr::<WgpuTexture>::new(&mut wgpu);
    let pixels = vec![1, 2, 3, 4, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120];
    let img = Resource::new(PixelImage::new(Cow::Owned(pixels), 2, 2, ColorFormat::Rgba8));

    let slice = mgr.store_image(&img, &mut wgpu);
    let bleed = guillotiere::euclid::SideOffsets2D::<_, ribir_types::PhysicUnit>::new_all_same(
      RGBA_BLEED_EDGE,
    );
    let atlas_rect = slice.rect.outer_rect(bleed);

    wgpu.begin_frame();
    let texture = mgr.texture(slice.tex_id);
    let atlas_img = texture.copy_as_image(&atlas_rect, &mut wgpu);
    wgpu.end_frame();

    let atlas_img = block_on(atlas_img).unwrap();
    assert_eq!(atlas_img.pixel_bytes(), rgba_pixels_with_bleed(&img));
  }
}