Qt 5.8 and QPainter based rendering
Greetings Qt community,
I'm currently working on a feasability using embedded hardware (Xilinx Zynq).
It has no dedicated GPU so I'm experimenting with:
- Qt 4.8.7 (QtQuick 1.0)
- Qt 5.8 with OpenGL (QtQuick 2.0).
- Qt 5.8 with QtQuick 2D (QtQuick 2.0).
I'm building a multitouch interface with extensive use of scaling (for transitions inside Row(s) or ListView(s)).
To make it clean I'm using a custom QML component that renders SVG with the QPainter (based on QQuickPaintedItem for Qt 5).
This is what I get with a 3.0 scale:
Qt 4 does a good job at scaling SVG(s) or anything QPainter based.
I suspect that Qt 5 just caches a static texture for a given QQuickPaintedItem and simply scales it.
This gives a blurry output on both Qt 5 OpenGL and Software (QtQuick 2D).
Is there a way to force Qt 5 and QQuickPaintedItem to scale without using its blurry texture cache ?
Note: I'm a little bit surprised about the transition to QtQuick 2.0. The performance are there but they come with a significant graphical tradeof. Having a scenegraph, shaders and particles is cool but it shouldn't come at the expense of basic 2d rendering.
Let me know If I'm missing something,
I'd recommend bringing this question to the interest mailing list. You'll find there Qt's developers/maintainers. This forum is more user oriented.