Re: [ccp4bb]: How to make a movie

["David J. Schuller" <djs63@cornell.edu>]

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On Fri, 28 Dec 2001, Edward Berry wrote:

> Jeff Taylor wrote:
> > 
> > I wrote a simple morphing program a while back.  You give it two pdb
> > files (first and last) and the number of steps you would like and it
> > writes out pdb files with linearly interpolated coordinates.
> 
> That sounds almost too simple. Are bond lengths/angles preserved during 
> the morph? if a Histidine rotated 180* about CHI2, wouldn't the NE1 and 
> CE2 atoms pass through each other on the way to their new positions?  
> Do any morphing programs preserve bond lengths and angles during the 
> morph? Perhaps one could express the structure in terms of dihedral 
> angles and interpolate linearly between the starting and final values
> for the dihedral angles. Still in the case of large-scale movements 
> you might get one domain passing through another on the way to its 
> final position, where in nature it makes a two-stage movement to go 
> around.

i had a simpler question, which i have so far been unable to expand to 
flame-war size.  do the two files have to have the same number of atoms 
and/or residues?

=======================================================================
"Now that I'm a cranky, constipated old man I can afford to say that
 the younger generation of scientists makes me sick to my stomach."
                                                  - C.M. Kornbluth
=======================================================================
                        David J. Schuller
                        modern man in a post-modern world
                        MacCHESS, Cornell University
                        djs63@cornell.edu