> > But I get in trouble there is no easy way to separate scaling and > > (rotation+shear), right? Setting 1s on the diagonal is clearly nonsense, > > although that is what we (I) do now. > > > > > I wish I could answer, but I have no clear and general solution. For > instance, I browsed OGL doc yesterday and I still don't know if scale > and shear can be done in only one operation using F and glMultMatrixd. > Actually, I don't even understand how the current 4x4 matrix can shear > the box correctly... Do you know a good web page about this? > http://www.songho.ca/opengl/gl_transform.html#matrix doesn't work. > > For display, at least, one solution would be to draw the 12 edges one by > one (origin->Hsize[0],origin->Hsize[1],etc.). (note : there is commented > code in periController to recompute Hsize with refSize and F.) > > Perhaps list the precise problems here, so we can think about them. For > the most general answer on scaling/rotation split, I would think in > terms of R.U polar > factorisation(http://en.wikipedia.org/wiki/Finite_strain_theory), but > I'm not sure we really need that. I think I am on the right track now with this. Not as difficult as I tought.
_______________________________________________ Mailing list: https://launchpad.net/~yade-dev Post to : [email protected] Unsubscribe : https://launchpad.net/~yade-dev More help : https://help.launchpad.net/ListHelp
