Re: [Algorithms] Transforming Transformation Matrices From: - 2007-10-23 09:41 ```Looks about correct. Do a search on the "similarity transform" which is exactly what you're = after. -----Original Message----- From: gdalgorithms-list-bounces@... = [mailto:gdalgorithms-list-bounces@...] On Behalf Of = Josh Petrie Sent: Friday, October 05, 2007 4:43 AM To: 'Game Development Algorithms' Subject: [Algorithms] Transforming Transformation Matrices Hello, I have a collection of transformation matrices representing the animation of some vertices over time. These transformations exist in a particular coordinate space; I need to convert them into a new = coordinate space, and I'm having a little trouble deriving the appropriate math. I've called the matrix transforming from the original space (A) to the target space (B) M. The original animation transformation matrix is Xa and the desired transformation matrix (the value I want to find) is Xb. I've got = vertices Va and Va' in space A representing the original vertex and the vertex after being transformed by Xa; similarly there are vertices Vb and Vb' in = space B. The matrices are all affine maps. My thought process was as follows: Vb * inverse(M) should yield Va.=20 Va * Xa should yield Va'. Va' * M should yield Vb' (since M is affine). Thus, I should be able to get to Vb' from Vb by transforming by Xb, where Xb is Xb =3D inverse(M) * Xa * M Alas, this doesn't appear to work; my resulting animation is off - rotated 90 degrees about the Y axis (in space B). Is there a glaring = flaw in my reasoning that I've missed? Thanks, -- jmp=20 -------------------------------------------------------------------------= This SF.net email is sponsored by: Splunk Inc. Still grepping through log files to find problems? Stop. Now Search log events and configuration files using AJAX and a browser. Download your FREE copy of Splunk now >> http://get.splunk.com/ _______________________________________________ GDAlgorithms-list mailing list GDAlgorithms-list@... https://lists.sourceforge.net/lists/listinfo/gdalgorithms-list Archives: http://sourceforge.net/mailarchive/forum.php?forum_name=3Dgdalgorithms-li= st ```