ink-custom-brush-builder

Custom brushes in the Android Ink API are built around the BrushFamily hierarchy:

BrushFamily
├── InputModel (BrushFamily.InputModel.SlidingWindowModel or PASSTHROUGH_MODEL)
└── BrushCoat[] (one or more rendering layers)
    ├── BrushTip (shape: scaleX, scaleY, cornerRounding, rotationDegrees, slantDegrees, pinch)
    │   └── BrushBehavior[] (dynamic response to stylus or touch input)
    │       └── Tree: TargetNode(input = [Operators](input = SourceNode))
    └── BrushPaint (visual appearance)
        ├── SelfOverlap (ANY, ACCUMULATE, or DISCARD)
        ├── TextureLayer[] (BrushPaint.TilingTexture or BrushPaint.StampingTexture)
        └── BrushPaint.ColorFunction[] (OpacityMultiplier or ReplaceColor)

Create a Brush by combining a custom BrushFamily with a Compose Color, size, and epsilon: