On Sat, Nov 8, 2014 at 5:45 PM, Mark Gaiser <mark...@gmail.com> wrote: > On Sat, Nov 8, 2014 at 5:34 PM, Marian Beermann <pub...@enkore.de> wrote: >> Depending on the platform requirements it might be possible to always >> use OpenGL rendering in the application and back it up with a software >> rasterizer (e.g. llvmpipe). >> >> (Just by the way: even old and crappy (perfomance-wise) GPUs like old >> Intel GMAs or PowerVRs in ARM SoCs are always faster than drawing on the >> CPU. I also think there are hardly any devices around that do not >> support at least fixed-function OpenGL.) >> >> On 11/08/2014 05:28 PM, Mark Gaiser wrote: >>> Hi, >>> >>> The requirement are simple: 2D painting needs to be possible and i >>> want to toggle between raster and OpenGL. QML or _depending_ on the >>> GPU is out of the question. Animations are also not required. Things >>> that are required are zoomnig controls, selecting drawn objects and >>> rendering has to be high performance. It must be capable of drawing a >>> _lot_ of primitive objects (think about numbers between 100.000 and 1 >>> million). >>> >>> Given those requirements i know of two different ways to accomplish >>> the same result. >>> >>> 1. QWidget and QOpenGLWidget (new in Qt 5.4). They would both use >>> QPainter. Basically the 2dpainting example [1] that is provided with >>> Qt. >>> >>> 2. Using QGraphicsView. It defaults to raster based painting and can >>> be accelerated by calling setViewport(new QOpenGLWidget) on it. This >>> can be done in basically all of the GraphicsView examples [2]. >>> >>> Those are the options that i know of where it's possible to toggle >>> between hardware and software rendering. Is this it or are there even >>> more options out there in the Qt world? >>> >>> It's unclear to me which of the possible options is the advised way to >>> go when drawing something in 2D. Therefore my question: which one >>> would be the advised way to use given the requirements said earlier? >>> >>> [1] https://qt.gitorious.org/qt/qt/source/examples/opengl/2dpainting >>> [2] https://qt.gitorious.org/qt/qt/source/examples/graphicsview > > Please keep the list in. > > Sorry for not mentioning the target platform. That would be the > Windows desktop family, x86 and x64. It's fine if it runs on Linux, > but that isn't the target operating system. > OpenGL on the windows desktop is a bit of a annoyance. Besides that, > this application also has to work well in virtual environments where > depending on OpenGL or any GPU is really not that well supported. Thus > software rendering is a must have. Hardware rendering where possible. > > Note beforehand. I know about ANGLE and it's not an option in this case.
..?? Anyone? _______________________________________________ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest
