Struct RasterBuf 

pub struct RasterBuf {
    pub width: u32,
    pub height: u32,
    pub pixels: Vec<u8>,
}

RGBA8 raster, sRGB color space, premultiplied alpha. Layout is row-major, four bytes per pixel [R, G, B, A].

Fields

width: u32

height: u32

pixels: Vec<u8>

Implementations

impl RasterBuf

pub fn new(width: u32, height: u32) -> Self

pub fn filled(width: u32, height: u32, rgba: [u8; 4]) -> Self

pub fn is_blank(&self) -> bool

Whether every byte is zero — i.e. fully transparent everywhere. For premultiplied RGBA this means no coverage and no color at all (a valid premultiplied pixel with a == 0 also has rgb == 0). Scans in u128-wide chunks, so a canvas-sized buffer costs only tens of microseconds.

pub fn blank_shared(width: u32, height: u32) -> Arc<RasterBuf>

A shared all-zero raster of the given size.

A style with dozens of layers produces dozens of fully transparent rasters on any tile that lacks those features — every one of them identical, and each otherwise costing a full padded canvas. Handing out one interned buffer per size collapses them into a single allocation. The pool keeps at most one buffer per distinct canvas size, which in practice means one.

Callers must treat the result as immutable; RasterBuf is Clone, so any consumer needing to write copies first.

pub fn is_interned_blank(buf: &Arc<RasterBuf>) -> bool

Whether buf is the interned blank for its size — i.e. holding it costs nothing, because every other holder points at the same allocation. Memory accounting uses this to avoid charging one buffer’s worth of bytes to each of its dozens of holders.

pub fn pixel(&self, x: u32, y: u32) -> [u8; 4]

Trait Implementations

impl Clone for RasterBuf

fn clone(&self) -> RasterBuf

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for RasterBuf

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

Formats the value using the given formatter.