bendns' repos / fimg
fast image operations
Diffstat (limited to 'src/wgpu_convert.rs')
-rw-r--r--src/wgpu_convert.rs105
1 files changed, 105 insertions, 0 deletions
diff --git a/src/wgpu_convert.rs b/src/wgpu_convert.rs
new file mode 100644
index 0000000..c95346f
--- /dev/null
+++ b/src/wgpu_convert.rs
@@ -0,0 +1,105 @@
+use std::num::NonZeroU32;
+
+use wgpu::{util::*, *};
+
+use crate::Image;
+
+impl<T, const N: usize> Image<T, N> {
+ /// Get the size as a [`wgpu::Extend3d`].
+ pub fn wgpu_size(&self) -> Extent3d {
+ Extent3d {
+ width: self.width(),
+ height: self.height(),
+ depth_or_array_layers: 1,
+ }
+ }
+}
+
+impl<T: AsRef<[u8]>> Image<T, 4> {
+ /// Upload this image to the gpu, returning a [`wgpu::Texture`].
+ pub fn send(&self, dev: &Device, q: &Queue, usage: TextureUsages) -> Texture {
+ dev.create_texture_with_data(
+ &q,
+ &TextureDescriptor {
+ label: None,
+ size: self.wgpu_size(),
+ mip_level_count: 1,
+ sample_count: 1,
+ dimension: TextureDimension::D2,
+ format: TextureFormat::Rgba8Unorm,
+ view_formats: &[],
+ usage,
+ },
+ util::TextureDataOrder::LayerMajor,
+ self.bytes(),
+ )
+ }
+}
+
+impl Image<Box<[u8]>, 4> {
+ /// Downlodas a purportedly [`TextureFormat::Rgba8Unorm`] image from the gpu.
+ /// # Panics
+ ///
+ /// When a "error occurs while trying to async map a buffer".
+ pub fn download(
+ dev: &Device,
+ q: &Queue,
+ texture: &Texture,
+ (width, height): (NonZeroU32, NonZeroU32),
+ ) -> Self {
+ let mut encoder = dev.create_command_encoder(&CommandEncoderDescriptor { label: None });
+ let texture_size = Extent3d {
+ width: width.get(),
+ height: height.get(),
+ depth_or_array_layers: 1,
+ };
+
+ let row = width.get() as usize * 4;
+ let pad = {
+ let padding = (256 - row % 256) % 256;
+ row + padding
+ };
+
+ let output_buffer = dev.create_buffer(&BufferDescriptor {
+ label: None,
+ size: pad as u64 * height.get() as u64,
+ usage: BufferUsages::COPY_DST | BufferUsages::MAP_READ,
+ mapped_at_creation: false,
+ });
+
+ encoder.copy_texture_to_buffer(
+ wgpu::ImageCopyTexture {
+ aspect: wgpu::TextureAspect::All,
+ texture,
+ mip_level: 0,
+ origin: wgpu::Origin3d::ZERO,
+ },
+ wgpu::ImageCopyBuffer {
+ buffer: &output_buffer,
+ layout: wgpu::ImageDataLayout {
+ offset: 0,
+ bytes_per_row: Some(pad as u32),
+ rows_per_image: Some(height.get()),
+ },
+ },
+ texture_size,
+ );
+ q.submit(Some(encoder.finish()));
+
+ let buffer_slice = output_buffer.slice(..);
+ buffer_slice.map_async(wgpu::MapMode::Read, Result::unwrap);
+
+ dev.poll(wgpu::Maintain::Wait);
+
+ let mut out = crate::uninit::Image::<_, 4>::new(width, height);
+ for (padded, pixels) in buffer_slice
+ .get_mapped_range()
+ .chunks_exact(pad)
+ .zip(out.buf().chunks_exact_mut(row))
+ {
+ ::core::mem::MaybeUninit::write_slice(pixels, &padded[..row]);
+ }
+
+ unsafe { out.assume_init().boxed() }
+ }
+}