Thanks for all this. It is working great! Now comes the inverse question which should hopefully be easy. How do I apply an xform to a structure to update the viewer? Applying rotations to the model.openState.xform seems to have no effect. I would like to be able to reset to the original view by doing something like, model.openState.xform.multiply(model.openState.xform.inverse()). Thanks, Charlie On 11/28/05, Greg Couch <gregc@cgl.ucsf.edu> wrote:
On Mon, 28 Nov 2005, Charlie Moad wrote:
The repr of an xform shows the opengl rotation matrix. I want to get this efficiently in python, but I don't believe it is exposed. Could a getter please be added returning a 4x4 tuple, so a Numeric array can be trivial/efficiently made from it? If there is a current approach please let me know.
The new and improved method is to use the getCoordFrame method :-) and the coorresponding Xform.coordFrame constructor. I agree that it would be better for Python to have a method that returned a Numeric array.
Example:
>>> xf = chimera.Xform.zRotation(30) >>> x, y, z, o = xf.getCoordFrame() >>> print "x: %s, y: %s, z: %s, o: %s" % (x, y, z, o) x: 0.866025 0.5 0, y: -0.5 0.866025 0, z: 0 0 1, o: 0 0 0
Using getCoordFrame would simplify PDBmatrices.matrices.xform_matrix to be:
rx, ry, rz, t = xform.getCoordFrame() return ((rx[0], ry[0], rz[0], t[0]), (rx[1], ry[1], rz[1], t[1]), (rx[2], ry[2], rz[2], t[2]))
You could do something similar to construct a Numeric array.
Xforms have improved in the latest release. Now you can easily make copies of matrices using the constructor:
xformprime = chimera.Xform(xform)
or:
import copy xformprime = copy.copy(xform)
Type:
help(chimera.Xform)
to see all of the methods and static methods.
Hope this helps,
Greg Couch UCSF Computer Graphics Lab gregc@cgl.ucsf.edu