markDescendantNeedsPaint method

@override void markDescendantNeedsPaint()

Called when a descendant render object's paint output has changed.

Viewport render objects override this to invalidate their paint cache so the next paint call re-renders the child subtree.

Implementation

@override
void markDescendantNeedsPaint() {
  final shouldInvalidateCache = children.any((child) => child.paintDirty);
  super.markDescendantNeedsPaint();
  if (shouldInvalidateCache) {
    invalidateChildPaintCache();
  }
}