Hi Noam,
Glad you like ChimeraX!

(A) The way to color a clipped surface cap by the molecular liphilicity potential (MLP) or Coulombic electrostatic potential (ESP) is covered in this tutorial section:

<https://www.rbvi.ucsf.edu/chimerax/docs/user/tutorials/binding-sites.html#cap-example>

(B) The way to color a clipped surface cap by an atomic or residue attribute is to:

 1) color the underlying atoms by the atom or residue attribute (with command "color byattribute" or the Render by Attribute tool)

 2) use command "color zone" on the surface cap model to make it match the atoms.  You may need to use the disclosure triangles in the Models panel to figure out the model number of the surface cap model. 

Example: color zone #1.1.1 near #1 distance 3

<https://rbvi.ucsf.edu/chimerax/docs/user/commands/color.html#zone>

Since "N" heads are better than one, we generally recommend sending questions to chimerax-users@cgl.ucsf.edu (CC'd here) unless you are including data or figures that should remain private.

I hope this helps,
Elaine
-----
Elaine C. Meng, Ph.D.                       
UCSF Chimera(X) team
Department of Pharmaceutical Chemistry
University of California, San Francisco


> On May 10, 2023, at 7:40 AM, Noam Prywes <noam.prywes@gmail.com> wrote:
>
> Dr. Meng,
>
> I'm a postdoc at berkeley and I'm trying to make a figure where I slice a surface structure and color the clipped surface based on an attribute that I defined (example from a paper attached). I can get clipped surfaces to display the electrostatic potential but not my defined attribute (that I fed in using a .defattr file with a number for each residue). I also can't get the surface to color by lipophilicity.
>
> Do I need to make a .defattr file that colors by atom instead?
>
> Thanks for your help and the amazing service that is chimeraX.
>
> Best wishes,
> Noam