If I understand you correctly, you want to tweak the viewing frustum? You should be able to rotate and scale (move in and out) the clipping planes of an asymmetric viewing frustum (projection matrix) so that the four sides of intersection with the near clipping plane form a general quadrilateral. This should allow you to "tune" to the area of projection that you're interested in.
-Shayne -----Original Message----- From: osg-users-boun...@lists.openscenegraph.org [mailto:osg-users-boun...@lists.openscenegraph.org] On Behalf Of Alexander Dieterle Sent: Friday, May 06, 2011 3:59 AM To: osg-users@lists.openscenegraph.org Subject: [osg-users] Manual perspective distortion? Dear OSG Forum readers, as we recently installed a multi-projector-based viewing screen I am currently working on its calibration. I managed to fix most of the displaying issues so far; however, one issue remains that I am quite unsure of how to approach it. Due to the mounting of the projectors in relation to the viewing screen, the projected image is distorted in a way that the projected image no longer resembles a rectangele but a trapezium. To give you a better understanding of the situation, I made a small sketch to visualise the problem (compare attachment). The grey area is the projection area, while the blue frame resembles the area displayed by the projector. As can be seen in the image, whilst the left and bottom corners are quite well aligned, the upper right corner flees the projection area. Since the mounting of the projectors cannot be changed or adjusted further, I have to solve the problem on software side. I was thinking of somehow manually creating a perspective distortion matrix, such that I can "move" that corner so it fits in the projection area. However, I am a bit lost how to do that. Is there anyone who could point me into the direction of how such a matrix could be created and what matrix to use at all? Intuitively, I've searched a bit in the direction of a projetion matrix, but couldn't quite find the right way to do it yet! Anyways, thank you very much in advance for reading :) Best regards, Alexander ------------------ Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=39083#39083 _______________________________________________ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
