paintBoxModel method
Implementation
void paintBoxModel(PaintingContext context, Offset offset) {
// If opacity to zero, only paint intersection observer.
if (alpha == 0) {
paintIntersectionObserver(context, offset, paintNothing);
} else if (isScrollingContentBox) {
// Scrolling content box should only size painted.
performPaint(context, offset);
} else {
// Paint fixed element to fixed position by compensating scroll offset
double offsetY =
scrollingOffsetY != null ? offset.dy + scrollingOffsetY! : offset.dy;
double offsetX =
scrollingOffsetX != null ? offset.dx + scrollingOffsetX! : offset.dx;
offset = Offset(offsetX, offsetY);
paintColorFilter(context, offset, _chainPaintImageFilter);
}
}