Struct RenderTarget 

pub struct RenderTarget {
    pub color_texture: Texture,
    pub color_view: TextureView,
    pub msaa_view: Option<TextureView>,
    pub width: u32,
    pub height: u32,
    pub sample_count: u32,
    /* private fields */
}

An off-screen GPU render target.

Wraps a Rgba8Unorm texture (single-sample, RENDER_ATTACHMENT | COPY_SRC | TEXTURE_BINDING) and an optional MSAA resolve texture.

Fields

color_texture: Texture

The single-sample backing texture (always COPY_SRC for readback).

color_view: TextureView

Default view over color_texture.

msaa_view: Option<TextureView>

Optional MSAA multisample texture view. Present when sample_count > 1.

width: u32

Target width in physical pixels.

height: u32

Target height in physical pixels.

sample_count: u32

Effective MSAA sample count (1 = no MSAA, 4 or 8 = MSAA).

Implementations

impl RenderTarget

pub fn new( device: &Device, width: u32, height: u32, sample_count: u32, ) -> Result<Self, UiError>

Create a new off-screen render target of width × height pixels with the given MSAA sample_count (1 = no MSAA).

If sample_count > 1 but MSAA is not supported for TARGET_FORMAT by the adapter, sample_count falls back to 1 silently.

Errors

Returns UiError::Unsupported if width or height is zero.

pub fn new_simple( device: &Device, width: u32, height: u32, ) -> Result<Self, UiError>

Create a new render target with no MSAA (sample_count=1).

Convenience wrapper around RenderTarget::new.

pub fn color_attachment(&self) -> (&TextureView, Option<&TextureView>)

Returns the colour attachment view and optional resolve target.

Under MSAA: (msaa_view, Some(&color_view)) — render into the MSAA surface, resolve into the backing texture. Under no MSAA: (&color_view, None) — render directly into the backing texture.

pub fn texture_view(&self) -> &TextureView

A view over the resolved (single-sample) backing texture.

Use this view for compositing the render target into a parent pass or for sampling in a shader.

pub fn mark_dirty(&mut self)

Mark the render target as dirty (needing re-render).

pub fn mark_clean(&mut self)

Mark the render target as clean (up-to-date).

pub fn is_dirty(&self) -> bool

Return true if the content is stale and needs re-rendering.

pub fn readback_rgba( &self, device: &Device, queue: &Queue, ) -> Result<Vec<u8>, UiError>

Read the render target’s pixel contents back to CPU memory as a tightly packed width * height * 4 RGBA byte vector.

Row padding (from COPY_BYTES_PER_ROW_ALIGNMENT) is stripped.

Errors

Returns UiError::Render if the GPU poll or buffer mapping fails.

pub fn resize( &mut self, device: &Device, new_width: u32, new_height: u32, ) -> Result<(), UiError>

Resize the render target to new dimensions.

All existing texture resources are dropped and recreated. Any previously-held views or samplers that refer to the old textures become invalid. The dirty flag is set to true.

Errors

Returns UiError::Unsupported if new_width or new_height is zero.