dragly
3rd May 2010, 18:59
I have a huge performance problem when I'm using QPainter's drawRect function in a QGLWidget on Maemo on the Nokia N900. The FPS drops to ~2-3 and the device is completely unusable. The performance hit is quite strange, as it does not appear all the time, but just most of the times I run the application on the device. Other times it runs fine, with an FPS of ~40-50.
The error is directly connected to the QPainter class, as I have a button in my application to activate the QPainter drawing of rectangles (used for menus and windows). Also, if I comment out the drawRect functions, but leave everything else as-is, it runs smoothly. QPainter's drawText function does run smoothly, however.
Running the application in Ubuntu or on Windows does not show a performance hit at all (not even slightly), so this is strictly related to the Maemo device. The device is running the libqt4-maemo5-* libraries.
Do you guys happen to know how I could try to debug this? I'm kind of stuck between wondering if there is something wrong with my mobile or Qt's drawRect-function - or my own code, of course.
The error is directly connected to the QPainter class, as I have a button in my application to activate the QPainter drawing of rectangles (used for menus and windows). Also, if I comment out the drawRect functions, but leave everything else as-is, it runs smoothly. QPainter's drawText function does run smoothly, however.
Running the application in Ubuntu or on Windows does not show a performance hit at all (not even slightly), so this is strictly related to the Maemo device. The device is running the libqt4-maemo5-* libraries.
Do you guys happen to know how I could try to debug this? I'm kind of stuck between wondering if there is something wrong with my mobile or Qt's drawRect-function - or my own code, of course.