imageRectOnDragCropRect method

Rect imageRectOnDragCropRect({ required Rect container, required Rect imageRect, required Rect cropRect, })

Implementation

Rect imageRectOnDragCropRect({
  required Rect container,
  required Rect imageRect,
  required Rect cropRect,
}) {
  double dx = -focalPointDelta.dx;
  if ((cropRect.width - container.width).abs() > 1) {
    final leftToFocalDistance = max(0.1, focalPoint.dx - cropRect.left);
    final rightToFocalDistance = max(0.1, cropRect.right - focalPoint.dx);
    if (focalPointDelta.dx < 0 && (cropRect.left - container.left).abs() < 1) {
      dx += 3 - min(3, leftToFocalDistance/rightToFocalDistance);
    } else if (focalPointDelta.dx > 0 && (cropRect.right - container.right).abs() < 1) {
      dx -= 3 - min(3, rightToFocalDistance/leftToFocalDistance);
    } else {
      dx = 0;
    }
  }

  double dy = -focalPointDelta.dy;
  if ((cropRect.height - container.height).abs() > 1) {
    final topToFocalDistance = max(0.1, focalPoint.dy - cropRect.top);
    final bottomToFocalDistance = max(0.1, cropRect.bottom - focalPoint.dy);
    if (focalPointDelta.dy < 0 && (cropRect.top - container.top).abs() < 1) {
      dy += 3 - min(3, topToFocalDistance/bottomToFocalDistance);
    } else if (focalPointDelta.dy > 0 && (cropRect.bottom - container.bottom).abs() < 1) {
      dy -= 3 - min(3, bottomToFocalDistance/topToFocalDistance);
    } else {
      dy = 0;
    }
  }

  return imageRect.translate(dx, dy).shiftToFitInside(container);
}