On Saturday 26 November 2016, Ch'Gans wrote: > So something tells me that, for some reasons, the drop shadow is > repainted way too many times, yet the app on the screen is updated > only once every second or so. > > Maybe the event loop is going crazy recursive or something like that? > Or the shadow could just be really expensive to calculate - which it is, and as far as I know it isn't being terribly clever either, so it just does an expensive blur on the entire source without trying to minimize the area processed. Using it on anything non-trivial in size is inadvisable.
Did you check how many times QPixmapDropShadowFilter::draw() was called? Btw. If you have big cycles in valgrind, you can add --separate-callers (=2 for instance) to the valgrind command line, so it will break more cycles automatically. `Allan _______________________________________________ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest
