> To be fair though, you still need to run glGets on both of those matrices, > plentry of 3rd party patches do adjust the projection matrix, so relying on > hard coded values would not work in situations where people use, say, the FOV > patch.
In general, patches should not be manipulating the Projection Matrix -- doing so is usually "wrong" http://www.sjbaker.org/steve/omniv/projection_abuse.html There are a few cases where it could be legitimate, but then: Supported 3rd party patches cannot have subpatches, so they shouldn't be modifying GL state generally in a destructive way. Supported patches also do not destructively modify the projection matrix (FPS display does temporarily, for example, but that's irrelevant because it cleans up after itself before anyone can notice), so pretending it's constant is "safe" in many situations. Like I said before: fetching the matrices "offline", and pretending they're constant is the only way this can work out of the box -- it /will/ have limitations (generally, any change to either matrix will render it invalid -- your case above is a special case of that statement), but it's "the best" you can do without using custom patches. If you can use custom patches then this is all irrelevant because you can just get the matrices and do the math yourself without adding any noodle magic to the composition. -- Christopher Wright [email protected] _______________________________________________ Do not post admin requests to the list. They will be ignored. Quartzcomposer-dev mailing list ([email protected]) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/quartzcomposer-dev/archive%40mail-archive.com This email sent to [email protected]
