Hi Daniel, I heard along time back that such support exists on the XBox... but I haven't ever seen any OpenGL extensions that support using the front buffer as a texture source.
Robert. On Wed, Mar 11, 2009 at 2:47 PM, Daniel Holz <osgfo...@tevs.eu> wrote: > Hi everyone, > > what I want is to obtain the z-Buffer content from a previous render pass > (pass1) where I render my scene and use it in a subsequent render pass > (pass2). Of course I would like to avoid doing pass1 twice, first to render > to the screen and second to render the z-buffer to a texture since I would > render my complete scene twice. That's is an overhead that I would like to > avoid. > > Now the question: > > Would it be possible to render the main scene (pass1) in two COLOR_BUFFERS, > COLOR_BUFFER0 and COLOR_BUFFER1 at the same time? > > Then one could set up the camera so that the screen is attached to > COLOR_BUFFER0 and a texture 'zBufferContent' is attached to COLOR_BUFFER1. > How do I do that? > > In this case, having multiple render targets, one needs to set up the camera > to using FBOs > (camera->setRenderTargetImplementation(osg::Camera::FRAME_BUFFER_OBJECT)) > since pixel buffers to not support multiple render targets. > > Then, in the fragment shader, one can write to gl_FragData[0] the usual > screen color information and pass gl_FragDepth to gl_FragData[1] > (gl_FragData[1] = gl_FragDepth), hence obtaining the texture which contains > the z-Buffer content. > > Would this work? > > Regards, > Daniel > > ------------------ > Read this topic online here: > http://forum.openscenegraph.org/viewtopic.php?p=8266#8266 > > > > > > _______________________________________________ > osg-users mailing list > osg-users@lists.openscenegraph.org > http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org > _______________________________________________ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
