bevy/crates/bevy_render
charlotte 40c26f80aa
Gpu readback (#15419)
# Objective

Adds a new `Readback` component to request for readback of a
`Handle<Image>` or `Handle<ShaderStorageBuffer>` to the CPU in a future
frame.

## Solution

We track the `Readback` component and allocate a target buffer to write
the gpu resource into and map it back asynchronously, which then fires a
trigger on the entity in the main world. This proccess is asynchronous,
and generally takes a few frames.

## Showcase

```rust
let mut buffer = ShaderStorageBuffer::from(vec![0u32; 16]);
buffer.buffer_description.usage |= BufferUsages::COPY_SRC;
let buffer = buffers.add(buffer);

commands
    .spawn(Readback::buffer(buffer.clone()))
    .observe(|trigger: Trigger<ReadbackComplete>| {
        info!("Buffer data from previous frame {:?}", trigger.event());
    });
```

---------

Co-authored-by: Kristoffer Søholm <k.soeholm@gmail.com>
Co-authored-by: IceSentry <IceSentry@users.noreply.github.com>
2024-09-30 17:28:55 +00:00
..
macros Simpler lint fixes: makes ci lints work but disables a lint for now (#15376) 2024-09-24 11:42:59 +00:00
src Gpu readback (#15419) 2024-09-30 17:28:55 +00:00
Cargo.toml bump async-channel to 2.3.0 (#15497) 2024-09-28 19:21:59 +00:00
README.md Add README.md to all crates (#13184) 2024-05-02 18:56:00 +00:00

Bevy Render

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