Hi Martin, About 15 years ago I did some work computing a best fit plane to a series of point used a least-squares alogrithm. I did the maths on paper and eventually derived a 4x4 matrix that I jut had to invert to get the result. I can't remeber the details though, you'll find stuff on this on the web these days though, you shouldn't have to derive things from first principles now. The osg::Matrix class has an invert so it should have all the maths support you need, you just need to work out the values to put in the matrix... that's the hard part.
Robert. On Mon, Apr 27, 2009 at 9:51 PM, Martin Beckett <m...@mgbeckett.com> wrote: > I need to align two data sets in OSG by fitting a small number of key points > and calculating the translation/rotation matrices. > > Normally this is done with a Helmert transform, that defines 7 parameters > (xyz translate, xyz rotate, linear scale) to convert between map coordinates. > GDAL seems to use Affine transforms instead - it has routine to apply > transforms but I can't find anything to calculate them. > > First has anyone else already done this? > Second - since it's going to involve pulling in a lot of Least-Squares/SVD or > other solver code is there a preferred numerical library? > > Martin > > ------------------ > Read this topic online here: > http://forum.openscenegraph.org/viewtopic.php?p=10933#10933 > > > > > > _______________________________________________ > osg-users mailing list > osg-users@lists.openscenegraph.org > http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org > _______________________________________________ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
