void pushClipPath(bool needsCompositing, Offset offset, Rect bounds, Path clipPath, PaintingContextCallback painter)

Clip further painting using a path.

  • needsCompositing is whether the child needs compositing. Typically matches the value of RenderObject.needsCompositing for the caller.
  • offset is the offset from the origin of the canvas' coordinate system to the origin of the caller's coordinate system.
  • bounds is the region of the canvas (in the caller's coodinate system) into which painter will paint in.
  • clipPath is the path (in the coodinate system of the caller) to use to clip the painting done by painter.
  • painter is a callback that will paint with the clipPath applied. This function calls the painter synchronously.

Source 

void pushClipPath(bool needsCompositing, Offset offset, Rect bounds, Path clipPath, PaintingContextCallback painter) {
  final Rect offsetBounds = bounds.shift(offset);
  final Path offsetClipPath = clipPath.shift(offset);
  if (needsCompositing) {
    _stopRecordingIfNeeded();
    final ClipPathLayer clipLayer = new ClipPathLayer(clipPath: offsetClipPath);
    _appendLayer(clipLayer);
    final PaintingContext childContext = new PaintingContext._(clipLayer, offsetBounds);
    painter(childContext, offset);
    childContext._stopRecordingIfNeeded();
  } else {
    canvas.saveLayer(bounds.shift(offset), _defaultPaint);
    canvas.clipPath(clipPath.shift(offset));
    painter(this, offset);
    canvas.restore();
  }
}