On Tue, May 6, 2014 at 6:51 AM, Patrick McMunn <doctorwho...@gmail.com> wrote: > I'm using some older hardware - an ATI Radeon 9200 - which can only handle > up to OpenGL 1.2. I was wondering if it's possible to use the hardware > renderer generally and have the driver hand off the handling of functions > which my video card can't handle (such as functions from a higher OpenGL > version) to the software render and then the software render hand control > back to the hardware renderer once it's finished. If this isn't currently > possible, is this perhaps a feature which might appear in the future?
To add to what others have said, this is not only currently not possible, but also incredible difficult to do in a standard-compliant way, because you need to have a software rasterizer that bitwise matches the result of the GPU. One example where this is needed is rasterization. If your software rasterizer doesn't provide the exact same result as the hardware rasterizer, you'll end up with gaps or overdraw between two adjecent polygons that ended up being using hardware and software rasterizing. To add to this, OpenGL allows slack in the rasterization result, and different GPUs rasterize differently. Matching these things is far from trivial, and requires knowledge about the hardware implementation that is usually not documented, even in the vendors' internal documentation. And do note that rasterization is just one example from a huge array of features that needs to match. So no, it's just not a feasible task. _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev