Struct NativeSurface

pub struct NativeSurface {
    pub opaque: NativeSurfaceId,
    pub alpha: NativeSurfaceId,
}

Represents the native surfaces created for a picture cache, if using a native compositor. An opaque and alpha surface is always created, but tiles are added to a surface based on current opacity. If the calculated opacity of a tile changes, the tile is invalidated and attached to a different native surface. This means that we don’t need to invalidate the entire surface if only some tiles are changing opacity. It also means we can take advantage of opaque tiles on cache slices where only some of the tiles are opaque. There is an assumption that creating a native surface is cheap, and only when a tile is added to a surface is there a significant cost. This assumption holds true for the current native compositor implementations on Windows and Mac.

Fields

opaque: NativeSurfaceId

Native surface for opaque tiles

alpha: NativeSurfaceId

Native surface for alpha tiles