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On Fri, Dec 9, 2011 at 8:48 PM, Chris Tipney <chris@xxxxxxxxxx> wrote: > Ok so I'm not explaining this very well.... > > At the risk of displaying my ignorance, why would I not want to use the > latest version of OpenGL? If so what version should I consider using and > what hardware does it need? > > It's not a part of the course but I do need to be able to use OpenGL as part > of a final year project and at the moment this is far enough away to allow > me to get to grips with OpenGL before the 'rush' sets in... Most of the updates to OpenGL effect the shader programming, and add new features/new parts of the state you can do things, new things you can access. The difference this makes is only really going to effect you if you are pushing things to the limit and need top performance out of the latest hardware. I would have thought everything you wanted to do would be fine on a slightly older graphics card, anything open GL 3.X or better should be fine. 2.X is probably getting a bit legacy though. What kinds of things are you looking to do with openGL? What sort of data, how many verts/tris etc do you need to show? > > > > OpenGL functions DO NOT have to be in the gpu - often the driver will add > the support. > > OK so why do they have a recommended minimum hardware requirement ? > Presumably it's better (as in faster) to get the GPU to do the work. > In general openGL functions are all implemented in the driver which passes stuff directly out to the hardware unless you are using the mesa "software" driver which does things 100% on the CPU. Thats what you are doing with Vertex buffer objects, bound textures and shaders, keeping data directly in the memory on the gfx card. When you implement shaders you run your code on the GPU to modify things directly there, which is very fast and efficient. Software OpenGL is not necessarily slow, someone i know runs a linux VM (on windows host) using mesa open GL driver, and they get a significantly better frame rate for identical setup than i do on my laptops. Robin -- The Mailing List for the Devon & Cornwall LUG http://mailman.dclug.org.uk/listinfo/list FAQ: http://www.dcglug.org.uk/listfaq