Trait Renderer

Source

pub trait Renderer {
    type Scene: SceneBuilder;

    // Required methods
    fn scene(&mut self) -> &mut Self::Scene;
    fn render_to_buffer(
        &mut self,
        width: u32,
        height: u32,
        background: Color,
        out: &mut [u8],
    ) -> Result<(), BackendError>;
}

Expand description

Owns backend resources (GPU device, pipelines, etc.) and rasterizes a scene to an RGBA8 buffer.

SceneBuilder is the authoring surface; this trait is the “produce output” step. Split into two traits because authoring is pure CPU/infallible and rasterization is fallible/resource-owning — and the recording backend only needs SceneBuilder.

Required Associated Types§

Source

type Scene: SceneBuilder

Concrete scene type for this backend. Implements SceneBuilder.

Required Methods§

Source

fn scene(&mut self) -> &mut Self::Scene

Mutable access to the scene being built. Issue draw calls against this.

Source

fn render_to_buffer( &mut self, width: u32, height: u32, background: Color, out: &mut [u8], ) -> Result<(), BackendError>

Render the current scene into out, which must be exactly width * height * 4 bytes.

Pixels are RGBA8 with straight (un-premultiplied) alpha — the convention PNG and most CPU-side image libraries expect. Callers feeding the buffer to a compositor that assumes premultiplied alpha (CoreGraphics, Skia, Cairo, a SrcOver blend on the GPU) must premultiply first.