qpa: Fix rendering issue in blitter engine (negative scaling factors)
authorJulien Brianceau <jbrianceau@nds.com>
Wed, 7 Nov 2012 15:35:34 +0000 (16:35 +0100)
committerThe Qt Project <gerrit-noreply@qt-project.org>
Thu, 8 Nov 2012 10:35:15 +0000 (11:35 +0100)
commit5a9cdc701e6f7a5e9af09dddad9ca3a4834c252b
tree582b3a051847f48523e36945b49b20350593fe64
parent708985baa7753ad12aad986b4ab175f49b922be9
qpa: Fix rendering issue in blitter engine (negative scaling factors)

A 180° rotation results in a TxScale QTransform with negative scaling
factors (x=-1.0 y=-1.0). This is not properly handled by blitter paint
engine yet, so use software rendering fallback in this case.

This rendering issue can be seen when using "-webkit-transform" CSS
property in WebKit with DirectFB QPA platform.

cherry-picked from qt5/qtbase 07ea3cf0b3883979e84bd91a5dc6a7a126de3123

Change-Id: I0911fd1166a3968d0a1d6bcca47ce2b26866de44
Reviewed-by: Samuel Rødal <samuel.rodal@digia.com>
src/gui/painting/qpaintengine_blitter.cpp
tests/auto/qpainter/tst_qpainter.cpp