Enum SurfaceAlpha 

pub enum SurfaceAlpha {
    Premultiplied,
    Opaque,
    Straight,
}

How an AppTexture composes with widgets painted underneath it.

The choice affects blend state and lets opaque content skip blend math; it does not change z-order. Widgets above the surface in the paint stream still paint over it, regardless of mode.

Variants

Premultiplied

Texture carries premultiplied alpha. Default; matches Aetna’s internal blend convention.

Opaque

Texture is fully opaque. Backend skips blending — pixels written to the surface rect replace whatever was there. Pick this for 3D viewports and video where every output pixel is non-transparent.

Straight

Texture carries straight (unpremultiplied) alpha. Backend premultiplies in the shader before blending. Convenient for content authored in a paint app or rasterised by a third-party vector library that doesn’t premultiply.

Trait Implementations

impl Clone for SurfaceAlpha

fn clone(&self) -> SurfaceAlpha

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for SurfaceAlpha

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

Formats the value using the given formatter.

impl Default for SurfaceAlpha

fn default() -> SurfaceAlpha

Returns the “default value” for a type.

impl PartialEq for SurfaceAlpha

fn eq(&self, other: &SurfaceAlpha) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Copy for SurfaceAlpha

impl Eq for SurfaceAlpha

impl StructuralPartialEq for SurfaceAlpha