Comment 3 for bug 981210

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RJ Skerry-Ryan (rryan) wrote :

I'm very confused by this bug. In general to render a QImage, Qt first converts it to a QPixmap. In the case of a QGLWidget, QPixmaps have to be transferred to the graphics card first. One speedup that Qt does under the covers is cache the transferred QPixmap on the graphics card in the GPU's RAM. I'm just pretty surprised it's faster to draw a QImage than a QPixmap in some of these cases. I think that using QPixmap's is the "right" thing design-wise but it's troubling we are seeing these corruption issues.

Did white waveforms happen with Qt 4.8.3 on the netbook?