Use finer triangulations in NIH3D scripts

[kristen.browne@…]

Kristen showed images of molecular surfaces and bonds with flat-shaded triangles in ChimeraX GLTF that appeared more faceted then those produced by Chimera. Would like finer triangulations. This can be set with the "graphics quality" command for bonds, and for surfaces by using the gridSpacing option of the surface command.

Kristen and Phil will need to advise us on how fine the triangulations should be and whether it should depend on model size. Fine triangulations on large models will produce very large GLTF files.

[Eric Pettersen]

I would need feedback from Phil / Kristen about how they want "graphics quality" and "gridSpacing" settings to vary based on model size. Right now, "graphics quality" is not changed by the script. For blob presets and surfaces of structures >= 250K atoms, gridSpacing is 6. For smaller structures it varies from 0.5 to 2.5.

[Eric Pettersen]

We have sorted out the grid-spacing settings. Still need Phil/Kristen guidance on what "graphics quality" setting they would want for bonds -- probably varying by model size.

[Eric Pettersen]

Bonds and pseudobonds now use cross sections as requested by NIAID