Hello All. I don't normally like posting this kind of plea for help, but I'm completely stuck.
I am using OSG1.2, to do HDR RTT. I have a CameraNode (PRE_RENDER) with a RGB32F texture attached. Under this I have something simple - i.e. the OSG shiny cow. Alongside, I also have a NESTED_RENDER absolute projection camera, with a full-screen quad with the RTT texture on it. The quad has no tone-mapping shader at all. So far, pretty normal. Performance is fine and stable. However, if I add fog to the cow's stateset, performance gets much much worse; in fact, as you zoom in on the cow (i.e. as the cow occupies more of the texture) the frame rate gets lower and lower until it's effectively stopped. If I remove the RTT bits from the SG - i.e. detach the RGB32F texture, don't draw the quad - everything is fine. If the RTT texture is RGB8, everything is fine. This is all buried in a complex application; I haven't yet been able to duplicate this behaviour based on one of the examples, but I was hoping somebody might be able to tell me where to start looking. I have the following possibilites, in order of likelihood. I guess that it could be driver issues, or application memory management (e.g. not using ref_ptrs where I should have been, not clearing up, array bounds, that sort of thing), or the lack of a tone-mapping shader doing something funny on-card... I don't think it's worth me explaining any more, as its so app dependent, and consequently I'd quite understand if I got no replies at all. However, if anybody has seen this before, or has any ideas of where to start looking, or has any useful diagnostic tricks, I'd be grateful. Thanks, David
_______________________________________________ osg-users mailing list [email protected] http://openscenegraph.net/mailman/listinfo/osg-users http://www.openscenegraph.org/
