Philippe wrote: > Running my application under OSX Leopard and Windows XP, using bootcamp, > hence with the same hardware, I have always noticed that running under > Windows seems much faster. For instance run Assistant and scroll and > resize the window, it's quite a different feeling. > I have therefore run a very simplistic benchmark, see further. > Using the 4.5 rc1 32 bit supplied binaries, the results are (Mac Pro 2.8 > GHz), in RELEASE mode: > > Under Windows: > With QImage as paint device: 78 ms > With direct QPainter device: 78 ms > > Under OSX: > With QImage as paint device: 98 ms > With direct QPainter device: 562 ms > > Hence: > > 1) Drawing to a QImage is meant to be platform independant, > this means here that the VC++ 2008 compiler seems about 20% faster that > GCC. > I am wondering if using an alternate GCC version could help (LLVM-GCC 4.2 > ?)
This doesn't surprise the least. Visual Studio rocks when it comes to optimzing code ;) > 2) Using QPainter directly (OSX api) to draw is dead slow, 550% slower > that drawing to QImage. > I am wondering if there is any interest to this? Is it even normal? There are cases where CoreGraphics does better than the usecase you provided, but we are in general not happy with the performance we get from it. This is why we are opening up the option for switching to use different graphics backends on both OSX and X11. You can run applications with -graphicssystem raster (or even configure Qt with it to have enabled for all apps). You can also try with the highly experimental -graphicssystem opengl, but it probably won't look so good ;) - Gunnar _______________________________________________ Qt4-preview-feedback mailing list [email protected] http://lists.trolltech.com/mailman/listinfo/qt4-preview-feedback
