Focal blur

[olibclarke@…]

The following bug report has been submitted:
Platform:        Darwin-18.2.0-x86_64-i386-64bit
ChimeraX Version: 0.9 (2019-01-31)
Description
Hi,

(This is a feature request, not a bug.) Would it be possible to add the focal blur option of povray for rendering? I really like adding a depth of field effect particularly when showing density map figures.

Cheers
Oli

Log:
> camera ortho

> cofr centerOfView

> lighting soft

> lighting depthCueColor white

UCSF ChimeraX version: 0.9 (2019-01-31)  
© 2016-2019 Regents of the University of California. All rights reserved.  
How to cite UCSF ChimeraX  




OpenGL version: 4.1 INTEL-12.4.7
OpenGL renderer: Intel(R) Iris(TM) Graphics 6100
OpenGL vendor: Intel Inc.

[Tom Goddard]

Not sure how to implement this effect -- it is definitely doable doing multiple rendering passes at different depth windows on the GPU. It would be relatively slow maybe rendering 10-50 times slower than without the effect depending on number of layers used. I recall you experimented with this in May 2017 and I have example images in my email from then. Given the complexity of coding this and that it would likely be used by only a tiny fraction of ChimeraX users, I think it is unlikely to get implemented.

[Tom Goddard]

Example image with depth blur.

[Tom Goddard]

Same image without depth blur.

[olibclarke@…]

Hi Tom,

Isn’t it built into POV Ray? I think that is what pymol uses?

http://www.povray.org/documentation/view/3.7.0/47/

https://pymolwiki.org/index.php/FocalBlur

Completely understand if it’s too complicated to implement, although I do think it would be used quite a lot if it was available and easy to use.

Cheers
Oli

[Tom Goddard]

ChimeraX does not use POVRay. Based on our experience with POVRay in Chimera 1, of very few people using it, very slow rendering, appearance not matching the Chimera view because we did not put enough time into it, and complexity of including it in the distribution, I do not think ChimeraX will ever use POVRay. My previous comments were about having ChimeraX do the blurring itself so the effect could be seen interactively. Our experience with POVRay in Chimera 1 strongly suggested that if you can't interactively preview the appearance then special effects are nearly worthless because it is too hard to get a good image.

[olibclarke@…]

Fair enough, that makes sense.