[chimerax-users] silhouettes on mesh in ChimeraX

[Tom Goddard]

Hi Gabe,

  I agree the silhouette edges look bad on meshes.  ChimeraX cannot turn off silhouette edges on just meshes.  It uses the scene depth at each pixel to compute the edges and the mesh contributes to the scene depth.  This is a different method than Chimera used.  It has the advantage that it renders basically as fast as without silhouettes where Chimera renders about 2x slower with silhouettes.  The Chimera method won't work in ChimeraX because ChimeraX uses modern OpenGL (core profile) which no longer supports drawing linewidth greater than 1.  The Chimera algorithm worked by drawing the edges of every triangle in the scene with linewidth 2 and slightly behind the triangle.  This linewidth 1 only limitation of modern OpenGL also is a problem with meshes on retina displays where the lines are too thin and hard to see.

  At any rate, there are ways to provide silhouette edges only on some models but not meshes.  But they are hard to implement.  I'll make a ticket for it but don't expect to be able to do it with our limited resources.

	https://plato.cgl.ucsf.edu/trac/ChimeraX/ticket/2765

  So the best advice I have is show the atomic model and mesh without silhouettes or use Chimera.

	Tom

Examle of mesh with silhouette edges

> On Jan 18, 2020, at 4:01 PM, Gabriel Lander <glander at scripps.edu> wrote:
> 
> Hi Tom,
> One of the "go-to" representations to demonstrate the quality of a modeled PDB in an EM density is sticks shown in a volume mesh. In Chimera when you turn on silhouettes they would only show around the atoms, but not the mesh. This is not the case in ChimeraX, and renderings with silhouettes and meshes look really messy. Is there a way to specifically turn off silhouettes on meshes but not atoms?
> Thanks,
> -gabe
> 
> 

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://plato.cgl.ucsf.edu/pipermail/chimerax-users/attachments/20200121/31c5a913/attachment-0001.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image1.png
Type: image/png
Size: 783923 bytes
Desc: not available
URL: <http://plato.cgl.ucsf.edu/pipermail/chimerax-users/attachments/20200121/31c5a913/attachment-0001.png>