use std::borrow::Cow;
use wgpu::util::DeviceExt;
pub fn convert(
device: &wgpu::Device,
encoder: &mut wgpu::CommandEncoder,
source: wgpu::Texture,
format: wgpu::TextureFormat,
) -> wgpu::Texture {
if source.format() == format {
return source;
}
let sampler = device.create_sampler(&wgpu::SamplerDescriptor {
label: Some("iced_wgpu.offscreen.sampler"),
..wgpu::SamplerDescriptor::default()
});
#[derive(Debug, Clone, Copy, bytemuck::Zeroable, bytemuck::Pod)]
#[repr(C)]
struct Ratio {
u: f32,
v: f32,
_padding: [f32; 2],
}
let ratio = device.create_buffer_init(&wgpu::util::BufferInitDescriptor {
label: Some("iced-wgpu::triangle::msaa ratio"),
contents: bytemuck::bytes_of(&Ratio {
u: 1.0,
v: 1.0,
_padding: [0.0; 2],
}),
usage: wgpu::BufferUsages::COPY_DST | wgpu::BufferUsages::UNIFORM,
});
let constant_layout = device.create_bind_group_layout(&wgpu::BindGroupLayoutDescriptor {
label: Some("iced_wgpu.offscreen.blit.sampler_layout"),
entries: &[
wgpu::BindGroupLayoutEntry {
binding: 0,
visibility: wgpu::ShaderStages::FRAGMENT,
ty: wgpu::BindingType::Sampler(wgpu::SamplerBindingType::NonFiltering),
count: None,
},
wgpu::BindGroupLayoutEntry {
binding: 1,
visibility: wgpu::ShaderStages::VERTEX,
ty: wgpu::BindingType::Buffer {
ty: wgpu::BufferBindingType::Uniform,
has_dynamic_offset: false,
min_binding_size: None,
},
count: None,
},
],
});
let constant_bind_group = device.create_bind_group(&wgpu::BindGroupDescriptor {
label: Some("iced_wgpu.offscreen.sampler.bind_group"),
layout: &constant_layout,
entries: &[
wgpu::BindGroupEntry {
binding: 0,
resource: wgpu::BindingResource::Sampler(&sampler),
},
wgpu::BindGroupEntry {
binding: 1,
resource: ratio.as_entire_binding(),
},
],
});
let texture_layout = device.create_bind_group_layout(&wgpu::BindGroupLayoutDescriptor {
label: Some("iced_wgpu.offscreen.blit.texture_layout"),
entries: &[wgpu::BindGroupLayoutEntry {
binding: 0,
visibility: wgpu::ShaderStages::FRAGMENT,
ty: wgpu::BindingType::Texture {
sample_type: wgpu::TextureSampleType::Float { filterable: false },
view_dimension: wgpu::TextureViewDimension::D2,
multisampled: false,
},
count: None,
}],
});
let pipeline_layout = device.create_pipeline_layout(&wgpu::PipelineLayoutDescriptor {
label: Some("iced_wgpu.offscreen.blit.pipeline_layout"),
bind_group_layouts: &[&constant_layout, &texture_layout],
immediate_size: 0,
});
let shader = device.create_shader_module(wgpu::ShaderModuleDescriptor {
label: Some("iced_wgpu.offscreen.blit.shader"),
source: wgpu::ShaderSource::Wgsl(Cow::Borrowed(include_str!("shader/blit.wgsl"))),
});
let pipeline = device.create_render_pipeline(&wgpu::RenderPipelineDescriptor {
label: Some("iced_wgpu.offscreen.blit.pipeline"),
layout: Some(&pipeline_layout),
vertex: wgpu::VertexState {
module: &shader,
entry_point: Some("vs_main"),
buffers: &[],
compilation_options: wgpu::PipelineCompilationOptions::default(),
},
fragment: Some(wgpu::FragmentState {
module: &shader,
entry_point: Some("fs_main"),
targets: &[Some(wgpu::ColorTargetState {
format,
blend: Some(wgpu::BlendState {
color: wgpu::BlendComponent {
src_factor: wgpu::BlendFactor::SrcAlpha,
dst_factor: wgpu::BlendFactor::OneMinusSrcAlpha,
operation: wgpu::BlendOperation::Add,
},
alpha: wgpu::BlendComponent {
src_factor: wgpu::BlendFactor::One,
dst_factor: wgpu::BlendFactor::OneMinusSrcAlpha,
operation: wgpu::BlendOperation::Add,
},
}),
write_mask: wgpu::ColorWrites::ALL,
})],
compilation_options: wgpu::PipelineCompilationOptions::default(),
}),
primitive: wgpu::PrimitiveState {
topology: wgpu::PrimitiveTopology::TriangleList,
front_face: wgpu::FrontFace::Cw,
..wgpu::PrimitiveState::default()
},
depth_stencil: None,
multisample: wgpu::MultisampleState::default(),
multiview_mask: None,
cache: None,
});
let texture = device.create_texture(&wgpu::TextureDescriptor {
label: Some("iced_wgpu.offscreen.conversion.source_texture"),
size: source.size(),
mip_level_count: 1,
sample_count: 1,
dimension: wgpu::TextureDimension::D2,
format,
usage: wgpu::TextureUsages::RENDER_ATTACHMENT | wgpu::TextureUsages::COPY_SRC,
view_formats: &[],
});
let view = &texture.create_view(&wgpu::TextureViewDescriptor::default());
let texture_bind_group = device.create_bind_group(&wgpu::BindGroupDescriptor {
label: Some("iced_wgpu.offscreen.blit.texture_bind_group"),
layout: &texture_layout,
entries: &[wgpu::BindGroupEntry {
binding: 0,
resource: wgpu::BindingResource::TextureView(
&source.create_view(&wgpu::TextureViewDescriptor::default()),
),
}],
});
let mut pass = encoder.begin_render_pass(&wgpu::RenderPassDescriptor {
label: Some("iced_wgpu.offscreen.blit.render_pass"),
color_attachments: &[Some(wgpu::RenderPassColorAttachment {
view,
depth_slice: None,
resolve_target: None,
ops: wgpu::Operations {
load: wgpu::LoadOp::Load,
store: wgpu::StoreOp::Store,
},
})],
depth_stencil_attachment: None,
timestamp_writes: None,
occlusion_query_set: None,
multiview_mask: None,
});
pass.set_pipeline(&pipeline);
pass.set_bind_group(0, &constant_bind_group, &[]);
pass.set_bind_group(1, &texture_bind_group, &[]);
pass.draw(0..6, 0..1);
texture
}