Improved the gesture api.

Made properties in QPanGesture and QPinchGesture more consistent - all of them
have value, lastValue and totalValue. Documented that totalValue means the
value from the beginning of the gesture, while the 'value' - from the beginning
of the current sequence. This is especially useful on Windows when you zoom
with two fingers and then release one finger and touch again to continue
zooming.

Also added a workaround for native Rotate gesture on Windows which contain a
'bad' value in the first WM_GESTURE message in every gesture sequence.

Reviewed-by: Bradley T. Hughes

1 files changed, 4 insertions, 2 deletions

diff --git a/examples/gestures/imageviewer/imagewidget.cpp b/examples/gestures/imageviewer/imagewidget.cpp
index 7dbd084..a4ea238 100644
--- a/examples/gestures/imageviewer/imagewidget.cpp
+++ b/examples/gestures/imageviewer/imagewidget.cpp
@@ -123,8 +123,10 @@ void ImageWidget::panTriggered()
 void ImageWidget::pinchTriggered()
 {
     QPinchGesture *pg = qobject_cast<QPinchGesture*>(sender());
-    rotationAngle += pg->rotationAngle();
-    scaleFactor += pg->scaleFactor();
+    if (pg->rotationAngle() != 0.0)
+        rotationAngle += pg->rotationAngle() - pg->lastRotationAngle();
+    if (pg->scaleFactor() != 1.0)
+        scaleFactor += pg->scaleFactor() - pg->lastScaleFactor();
     update();
 }