On Sun, Jul 06, 2014 at 03:39:29PM -0400, Jonathan Wilkes wrote: > QGraphicsView looks like it has what I need to do this. Qt Quick looks > like it has a lot of great features but is conspicuously missing Bezier > curves, ellipses, or even line primitives. (I see it has an HTML5-style > canvas but I don't want to reinvent svg-style inheritance inside that.)
What do you mean about inheritance? > So if QGraphicsView is going to continue to be actively maintained it > looks like the best fit. There aren't plans at this point to add any new features though, only to keep it working, whereas QtQuick is being actively developed. But QtQuick has been developed around a small set of graphics primitives of which it's easy to get GPUs to render large quantities. Bezier curves and such aren't there because proper anti-aliasing of them is difficult, and there would be scaling issues if you try to render too many. I also think it's a hole which needs to be filled at some point. But GPUs are developed according to what game developers need nowadays, so there is not as much emphasis on accelerating vector graphics as there should be, IMO (in the world in general, not just in the Qt project). So the easy way is to use the raster engine (QPainter, QPainterPath and friends), which happens to use the CPU to do the work instead of the GPU (usually), but at least it can do the antialiasing. QGraphicsView and the QtQuick Canvas API both do that. The rendering is done on-demand into a texture instead of trying to render any kind of vector graphics that you like from scratch in every frame at 60FPS. Personally I don't think that goal is impossible, just more difficult and not done yet. And another benefit of QPainter et al. is support for printing. So I think for these reasons QGraphicsView will be around for some time, but I hope the future for vector graphics on the GPU eventually gets bright enough that we can have everything in Qt Quick some day. Anyway there is a playground project with some vector graphics stuff (Qt.labs.shapes): https://codereview.qt-project.org/#/admin/projects/playground/scenegraph into which I added a bezier "connector" https://codereview.qt-project.org/#/c/74246/ based on some of Gunnar's earlier work. Everything there needs refinement which is why it's in a playground project. _______________________________________________ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest
