HI Macro, The way to do what you want is to create a osg::Camera with a FrameBufferObject (to render with the existing context) or a Pbuffer and render your scene to this, then use the final draw callback on this camera to capture the image.
Robert. On Fri, Sep 9, 2011 at 12:49 PM, Marco Fiocco <[email protected]> wrote: > Hi, I need to render an offscreen image with a resolution of 2048x2048, and > I'm sure that the graphics card can do that because the max framebuffer size > is 8192x8192. > I'm doing that by using a newly instanced CompositeViewer with Qt and by > calling once frame(), then a screenshot callback captures the framebuffer. > The problem is: > if the current MONITOR screen has a resolution of 1024x768, the offscreen > shot is rendered only in the 1024x768 corner of the whole buffer size > (2048x2048), the rest is black. The aspect ratio of that piece is correct > though, i.e. the projection matrix is correctly set to render the resolution > of 2048x2048. > You can see the problem in the attached shots, one is the fullscreen > resolution, the other is the 2048x2048 offscreen shot. > fullscreen: http://cl.ly/2s2M0D3Q090R2w1r2w44 > offscreen: http://cl.ly/390L1k2o2k1B2P1r312r > Do you know what could be the problem? > Thanks in advance > Marco > > > _______________________________________________ > 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
