Performance when using qt-gfx-transformed option to rotate the screen

[whitewool]

Hi,

I'm working on a graphic application based on Qt-4.7.4 embedded (ARM9, Freescale i.mx233).
Graphics work on Linux framebuffer, the display driver is the default Freescale distribution one.
The application was natively written for a 320x240 display and I have to make it run on a 240x320 display, because it is the available LCD on the current hardware.

I read on previous discussions that I can obtain this by recompiling my app with the -qt-gfx-transformed option and launch the application with ./qt_app -qws -display "Transformed:90:0" &.
If that is the right way my question is:

• Does this compile option result in the same cpu consumption of the application, or greater?
  In other words, does Qt work always with a transformation on (a "neutral" one if I don't use the compile option) or does this Qt activate code requiring more cpu effort?

Any help is appreciated.

Thanks

Alberto

[bkamps]

I also use transform and framebuffer and i didn't notice any change in framerate (QML_SHOW_FRAMERATE environment variable). Try it yourself..