Tablet example: update only the drawn areas of the canvas

This makes an enormous difference in responsiveness on the iPad Pro:
it actually feels like real-time drawing with hardly any lag.

Change-Id: I17c3b948e818d4ee46b4d24934c929ab9b386e69
Reviewed-by: Richard Moe Gustavsen <richard.gustavsen@qt.io>

1 files changed, 1 insertions, 1 deletions

diff --git a/examples/widgets/widgets/tablet/tabletcanvas.h b/examples/widgets/widgets/tablet/tabletcanvas.h
index a1b31c65bf..671d5376f8 100644
--- a/examples/widgets/widgets/tablet/tabletcanvas.h
+++ b/examples/widgets/widgets/tablet/tabletcanvas.h
@@ -103,7 +103,7 @@ private:
     void initPixmap();
     void paintPixmap(QPainter &painter, QTabletEvent *event);
     Qt::BrushStyle brushPattern(qreal value);
-    qreal pressureToWidth(qreal pressure);
+    static qreal pressureToWidth(qreal pressure);
     void updateBrush(const QTabletEvent *event);
     void updateCursor(const QTabletEvent *event);