cacheOffset method

double cacheOffset(
  1. double from,
  2. double to
)

Computes the portion of the region from from to to that is within the cache extent of the viewport.

This method is identical to RenderSliver.calculateCacheOffset.

Implementation

double cacheOffset(double from, double to) {
  assert(from <= to);
  final minOffset = scrollOffset + cacheOrigin;
  final maxOffset = scrollOffset + remainingCacheExtent;
  from = from.clamp(minOffset, maxOffset);
  to = to.clamp(minOffset, maxOffset);
  // the clamp on the next line is to avoid floating point rounding errors
  return (to - from).clamp(0.0, remainingCacheExtent);
}