Add command to move models to center of rotation

[olibclarke@…]

From: Oliver Clarke via ChimeraX-users <chimerax-users@…>
Subject: [chimerax-users] move cofr?
Date: January 18, 2024 at 3:14:47 PM PST
To: Tom Goddard
Cc: ChimeraX Users Help <chimerax-users@…>
Reply-To: Oliver Clarke

Would it be possible to add a "move cofr" command to chimerax at some point? We use this frequently in Chimera to move an atomic model to a precise point in a map (when we often don't have any other models in there to align to).

I know one can do this graphically using "translate selected models", but it is much easier and more precise in my experience to position the center of rotation (using the showPivot indicator) where I want to be, and then move the model to the center of rotation.

Cheers
Oli

[Tom Goddard]

I don’t quite understand how this is useful. If you position a model at the center of rotation don’t you also have to rotate it to a sensible orientation. How do you do the rotation? Are you trying to do a fit in a map? I agree the current way that is done in ChimeraX where you have to move the map by hand is cumbersome. Maybe instead an option to the fitmap command to first move the model to the center of rotation and then optimize the fit (possibly with a rotational search) would better get at what are trying to do.

[olibclarke@…]

Yes an option for fitmap could do the trick, although a separate move cofr command would be more flexible in my opinion.

In Chimera, I would generally move the cofr where I want to position the model, \u201cmove cofr\u201d to move it, then I would either use fitmap with global search (\u201csearch 100 radius 5\u201d) or quickly manually reorient (which I do about equally as often). It might sound cumbersome but feels pretty quick and intuitive!

Either way, I find being able to reposition a model to the center of rotation useful.

Cheers
Oli

[Tom Goddard]

Done.

I added a "move cofr <models-spec>" command, for example,

move cofr #2

Syntax is slightly different than in Chimera which required a "models" keyword. Also the distance and frames options seen in the Chimera command are not in ChimeraX.

If multiple models are specified they are moved rigidly as a group so that their bounding box center (displayed parts only) is moved to the current center of rotation.