That would work, but I can't really afford the per-frame cost - I'm trying to only pay for picking when it's actually being used (in which case a pretty high lag is fine). Maybe I should be asking this differently - what's the best way to render one frame of a small portion of my scene graph off screen and read back the results?
Max On Fri, Sep 27, 2013 at 5:19 PM, Aurelien Albert < [email protected]> wrote: > Hi, > > I've got the same picking problem with several mesh (which use vertex > displacement or tesselation). > > To solve that, I always render my scene in a FBO, with 2 color > attachements : > - first draw buffer is a regular color texture > - second draw buffer is a texture with only 1 channel, in "int" format > > My shaders always write an "objectId" value in the second buffer. Then I > can pick a pixel at anytime. You can also get the 3D world position of the > pixel using its window coordinates, its depth value and the camera matrices. > > This not ideal picking, it consume a lot of GPU memory bandwitdh (but on > modern GPUs it's not a problem), but it's easy to setup and for > applications which need exact picking it may be the best solution. > > > Cheers, > Aurelien > > ------------------ > Read this topic online here: > http://forum.openscenegraph.org/viewtopic.php?p=56528#56528 > > > > > > _______________________________________________ > osg-users mailing list > [email protected] > http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org >
_______________________________________________ osg-users mailing list [email protected] http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
