Blend modes

BlendMode sits on the paint. The default is SrcOver. Modes that read the destination (Overlay through Luminosity) snapshot the target and run in a shader — they cost a pass break.

let mut paint = Paint::from_color(Color::rgb(0.78, 1.0, 0.24));
paint.blend_mode = BlendMode::Multiply;

paint.setBlendMode(BlendMode.Multiply);

Left to right: SrcOver, Multiply, Screen.

Porter-Duff

Clear, Src, Dst, SrcOver, DstOver, SrcIn, DstIn, SrcOut, DstOut, SrcAtop, DstAtop, Xor, Plus, Modulate, Screen.

These use fixed-function blending except where noted as destructive (Clear, Src, SrcIn, …) — transparent source can then change pixels outside the ink.

Separable and HSL

These always snapshot:

Overlay, Darken, Lighten, ColorDodge, ColorBurn, HardLight, SoftLight, Difference, Exclusion, Multiply, Hue, Saturation, Color, Luminosity.

A shader paint with an advanced blend is drawn into an implicit layer first, then composited.