Struct ImageData 

pub struct ImageData {
    pub id: u64,
    pub width: u32,
    pub height: u32,
    /* private fields */
}

Fields

id: u64

Content address: equal pixels at equal dimensions give equal ids, whoever built them and whenever.

The renderers key their texture caches on this and nothing else, so the id has to identify the image. A per-construction counter identified the allocation instead: a caller that rebuilt the same image each frame — which is what building an ImageData inside a widget body does — minted a fresh key every time, and every entry behind it became unreachable weight the cache could only shed by hitting its byte budget.

An external texture cannot be hashed, so its owner supplies the id and carries the same duty: keep it stable while the texture is, and change it when the texture object is replaced.

width: u32

height: u32

Implementations

impl ImageData

pub fn new(pixels: Vec<u8>, width: u32, height: u32) -> Self

pub fn from_premultiplied(pixels: Vec<u8>, width: u32, height: u32) -> Self

Builds from bytes that are ALREADY premultiplied (e.g. a resvg Pixmap), skipping the premultiply step new() performs.

pub fn external( texture: Arc<dyn ExternalTexture>, id: u64, width: u32, height: u32, ) -> Self

Refers to a texture the application owns and keeps filling, rather than pixels Telar uploads.

id addresses the texture object, not its contents: the whole point is that the contents change every frame without Telar being told. Bump it only when the texture itself is replaced — a resize, a format change — so the bind group built against the old one is dropped.

pub fn pixels(&self) -> &[u8]

The premultiplied RGBA8 bytes; empty when the picture lives in a texture Telar does not own.

Empty rather than Option so a backend that cannot use an external texture needs no special case: every path that turns these bytes into a raster already has to reject a buffer too short for the dimensions, and an empty one takes that branch.

pub fn external_texture(&self) -> Option<&Arc<dyn ExternalTexture>>

Trait Implementations

impl Clone for ImageData

fn clone(&self) -> ImageData

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for ImageData

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.