Ian Romanick wrote: > -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 > > Roland Scheidegger wrote: >> So, when trying to implement ARB_point_parameters and >> ARB_point_sprite, I came across some problem (this tnl stuff is >> hard to follow). The problem is, I need to set some hardware state >> dependant on the primitive being renderered (in particular, r200 >> needs perspective correction disabled for point sprites, as >> otherwise the tex coord interpolator will wreak havoc with the >> (hw-generated) point sprite texture coordinates). Obviously, this >> should only be disabled when actually rendering points. However, if >> there are no state changes between a glEnd and glBegin command, no >> usual state validation will happen. Am I missing something, or is >> it more or less impossible to emit state depending on the >> primitive? > > I thought there was a mechanism that allowed the driver to be > notified at glBegin (or similar) time. It seems like you ought to be > able to emit some extra state at that time to change to / from > point-sprite mode. Ah, sounds like a plan. I thought the NotifyBegin would only be useful for vtxfmt-replace like things. I'll look into that.
>> Same problem also exists for sw tcl - additionally there we'd want >> to change the vertex format (for point parameters attenuation), as >> it's highly inefficient to submit per-vertex point size if we >> aren't drawing points... > > You might be able to do this in the begin-notify routine also. > Alternately, you could add an extra pipeline stage that does the > required tweaking. I hope the NotifyBegin should be enough. Roland ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys -- and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV -- _______________________________________________ Dri-devel mailing list Dri-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/dri-devel
