Hi Uma, On 19 December 2016 at 09:08, Uma Devi Selvaraj <[email protected]> wrote: > Can somebody tell me is it possible to get pixel value from x and y > co-ordinates?
You can implement a draw callback that uses glReadPixels() if you want the actual pixel value. This however limits to you doing the operation in the draw traversal and forces a round trip to the GPU which is slow process. Normally when you want to intersect the scene at the mouse x,y position you'll using osgViewer::View::computeIntersections() or the osgUtil::IntersectionVisitor with LineSegmentIntersector. You can get the intersection values and tex coords from the intersection which then can be used to query the osg::Texture and finally the osg::Image for it's value. This route is CPU based and avoids the round trip cost. Robert. _______________________________________________ osg-users mailing list [email protected] http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
