Ken, I don't have access to another implementation at the moment -- can you test?
-- Chris On Wed, Nov 13, 2013 at 9:57 AM, Kenneth Graunke <kenn...@whitecape.org> wrote: > On 11/12/2013 12:35 PM, Paul Berry wrote: >> On 12 November 2013 12:13, Kenneth Graunke <kenn...@whitecape.org >> <mailto:kenn...@whitecape.org>> wrote: >> >> It would be great to put a citation for this: >> >> /* From the ARB_multi_draw_indirect specification: >> * "INVALID_VALUE is generated by MultiDrawArraysIndirect or >> * MultiDrawElementsIndirect if <primcount> is negative." >> * >> * "<primcount> must be positive, otherwise an INVALID_VALUE error will >> * be generated." >> */ >> >> These beg the question of whether 0 is allowed. Usually I interpret >> "negative" as < 0, "positive" as >= 0, and "strictly positive" as > 0. >> So I think zero should be allowed, and I don't see a contradiction. >> >> The only text I can find in 4.3 and 4.4 just reiterate that it needs to >> positive, and I don't see any text defining "positive." >> >> >> In the absence of text defining "positive", shouldn't we go with the >> definition used by mathematicians? According to >> http://en.wikipedia.org/wiki/Sign_%28mathematics%29#Terminology_for_signs, >> "positive" means strictly greater than zero. > > Mathematicians are inconsistent in their use of terminology. Positive > can mean either > 0 or >= 0 depending who you talk to and in what > context. And the GL specification authors are notoriously non-precise. > >> If anyone is aware of a competing implementation that accepts a >> primcount of 0, then I'd be open to following the behaviour of the >> competing implementation (and filing a spec bug). But otherwise I think >> we should prohibit zero. > > Then I suppose I have to go test AMD or nVidia. > >> (Note: I brought this up last time the patch was reviewed: >> http://lists.freedesktop.org/archives/mesa-dev/2013-November/047962.html) _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev