Hi,

I have something odd going on with QPainter/QPixmap that I don't understand.
Before I start - I'm not using OpenGL.

I have a image which is 1798x1709x24bit (it's a texture map which contains multiple textures).
I load it into a Pixmap and use QPainter::drawPixmap to draw a sub-sections of it.
This works as expected on my PC with a low end graphics card.

I've just discovered on a friend's PC that the pixmap is not rendered at all when QPainter::drawPixmap is called (exactly the same binaries were used in both cases, the image is embedded as a resource).

I also load other images from other resources (much small images) and sub-sections of these are using the same QPainter::drawPixmap calls.
These images are rendered correctly.

The end result is there is a large transparent empty space where the big image should be surrounded by smaller images.

We've verified that the QPixmap loaded with the image returns the correct dimensions, etc, so it appears that the QPainter::drawPixmap call is failing silently.

Are there any known issues with QPixmap/QPainter on different flavors of graphics HW?
(should images ideally be power-of-2 when they are used for textures?)
(He has a mid-range to higher end graphics card)

Are there any good debugging techniques that I could use to find out the root cause of this issue?

Also, assuming it is a HW issue, is there an API I can use to determine the limitations of the HW so that I can adjust things on the fly so my SW works for all HW?

Thanks
J