On Tue, 26 Feb 2013 06:05:15 +0100 Michalis Kamburelis <[email protected]> wrote:
> Reimar Grabowski wrote: > > Hi, > > > > as the title says multisampling does not work for me. > > I was testing TOpenGLControl.MultiSampling on Linux (with Radeon GPU), > it worked fine for me. > > Note that there is a fallback (documented in TCustomOpenGLControl > interface): if the requested MultiSampling is not available, we fallback > to non-multisampled context (that's because for most applications > anti-aliasing can be just an optional feature). I guess you already > checked that this didn't happen in your case? I checked: There is no error, so the fallback is not called. > The code is pretty straightforward, in glgtkglxcontext.pas > LOpenGLCreateContextCore gets called with given MultiSampling value, and > then CreateOpenGLContextAttrList adds to the attributes this: > > Add(GLX_SAMPLE_BUFFERS_ARB); Add(1); > Add(GLX_SAMPLES_ARB); Add(MultiSampling); > > The GLX_SAMPLES_ARB is the minimal required value (as > http://www.opengl.org/registry/specs/ARB/multisample.txt says > "...accepts GLX_SAMPLES_ARB in <attribList>, followed by the minimum > number of samples that can be accepted in the multisample buffer"). So > it should work... Well, unless GLX is just lying to us. > > Can you check what list was created in your case by > CreateOpenGLContextAttrList, did it contain appropriate GLX_SAMPLES_ARB > and MultiSampling items? Yes, it does and the copy contains them too. Mattias -- _______________________________________________ Lazarus mailing list [email protected] http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
