We continue to enforce the drag threshold in local (transformed) coordinates: if Flickable should wait until the user drags 12 pixels, but it's scaled to half-size, it will start dragging after only 6 pixels of movement, for example. But if it's also rotated, then the required distance becomes a projection of the actual drag vector onto the vector along which the Flickable should move past the (scaled) drag threshold. I.e. if we rotate the Flickable's parent by 45°, the required distance should be 12 / 2 * √2 ≈ 8.5; 9 pixels will exceed the threshold, then. tst_qquickflickable::clickAndDragWhenTransformed is modified to prove it (at least when a 2D scale is applied). The test should be OK on hidpi because qApp->styleHints()->startDragDistance() is already adjusted. Change-Id: I035a462c75e7c5aba876a67c1b996bccab2c5364 Reviewed-by: Shawn Rutledge <shawn.rutledge@qt.io>