Qt slows down when it processes [large] images. Anything you want to display on screen has to be processed to a QtPixmap structure. When I last used it, with su

Qt slows down when it processes [large] images. Anything you want to display on screen has to be processed to a QtPixmap structure. When I last used it, with sufficiently large textures and/or splash screen images, this operation could take long enough to cause the rendering thread to skip frames. (In an embedded x86 environment we were talking about some hundreds of milliseconds.) The other part where Qt can really slow down is when you have to instantiate a 3D driver module. That can block absolutely everything.