HI Alice, The osgdistortion example would probably be a good place to start, as it renders the scene to texture using a slave render to texture camera, then has another slave camera render a screen aligned geometry using that texture. The only thing you'd need to change is the osgdistortion example alters the tex coords to achieve the desired distortion, in your case you could just use a single quad with undistorted tex coords.
One thing you absolutely don't want to be doing is reading the contents of the frame buffer back into main memory though, this will certainly kill performance - always use a FrameBufferObject (FBO) and associated Texture to render to. The osgdistortion example sets up the render to texture camera to use FBO by default. Robert. On Mon, Aug 9, 2010 at 1:40 AM, Alice Yin <yin...@ymail.com> wrote: > Hi, everyone > > I am completely a starter of OSG. I just read a few tutorials about OSG. But > now, I need to implement my code in openGL to OSG in one week. > > The main idea is to render the scene twice. The first time I render it in a > low resolution, read back from the frame buffer, use the data I get from the > buffer to render the second time in normal resolution. Only the second time, > the user can see the result. A friend of mine suggest me to read the > prerender example, I am doing it, though very slowly. I just want to make > sure I am in the right way because the deadline is approaching. > > Thank you! > > Alice > > ------------------ > Read this topic online here: > http://forum.openscenegraph.org/viewtopic.php?p=30631#30631 > > > > > > _______________________________________________ > 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
