Hello Gianluca, I think, and I'm not exactly sure about it that if the matrix W component (4th column) is zero, then the computation works with the 3x3 matrix. When it is different than zero, it uses it as 4x4 matrix. Now supposed that startProj or endProj has in the 4th column zero, and the other one has something different than zero, then all the animation matrices will be 4x4 but the first or the last, and therefore the reason on the discontinuity.
Check if that happens for any N and check if both matrices are 4x4 or 3x3. If one of them is 3x3 than set it's 4th component to one. From: [email protected] [mailto:[email protected]] On Behalf Of Gianluca Natale Sent: Wednesday, February 29, 2012 7:16 PM To: Osg Users Subject: [osg-users] animation from one projection type to the other one Hi all, I'm trying to implement an animation from a perspective projection to an orthographic one. What I'm computing at each step is a weighted linear combination of 2 projection matrices (the start, that refers to a perspective projection, and the end, which is an orthographic projection). So, supposing the whole animation in N steps, at step n my projection matrix is defined by: Proj(n) = startProjMat * (1 - n/N) + endProjMat * n/N. The animation looks fine, but in the last step there is a noticeable jump on the screen. What did I go wrong? Is there any unpredictable or invalid result in the linear combination I computed, or is it a well defined projection matrix? Thanks Gianluca
_______________________________________________ osg-users mailing list [email protected] http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
