VMD-L Mailing List

From: John Stone (johns_at_ks.uiuc.edu)
Date: Wed Feb 11 2015 - 10:21:09 CST

Norman,

On Wed, Feb 11, 2015 at 04:32:35PM +0100, Norman Geist wrote:
> 1. Using the "ruler" in "scale" mode, when nothing else (including
> axis) is visible, TachyonOptix will crash.

I don't get a crash when I do this on my system here, but I will
say that the rendering of the scale bar is pretty wacky due to
weaknesses in the scheme I used for setting cylinder radii for OptiX
when drawing lines in VMD 1.9.2, something that still needs more work.
Can you post the error message that VMD prints?
Without the error it's hard to say what's going on there for you.

> 2. The general fact TachyonOptix will no more work without
> restarting VMD, if it has crashed once.

It depends. If the OptiX runtime runs out of GPU memory or other
scenarios that it can't bail out of, it will terminate rendering and
usually destroy the OptiX context on its way down. In some of these cases,
the state of the CUDA context also gets destroyed, and VMD is not able to
recover it. There are also a lot of cases where VMD does recover from
less serious issues, but unfortunately, I'd say that running the GPU out
of memory is one of the more common problems, particularly on a machine
where other graphical apps are competing for resources (e.g. Google Chrome,
a surprisingly resource hungry application, in terms of GPU memory...)

Cheers,
  John

> Norman Geist.
>
>
>
> From: owner-vmd-l_at_ks.uiuc.edu [mailto:owner-vmd-l_at_ks.uiuc.edu] On Behalf
> Of Tristan Croll
> Sent: Wednesday, February 11, 2015 12:15 PM
> To: vmd-l_at_ks.uiuc.edu
> Subject: vmd-l: Handful of rendering issues
>
>
>
> Hi there,
>
>
>
> I have a few minor rendering-related issues/suggestions in VMD 1.9.2:
>
>
>
> - If I have an isosurface visualised in the default point representation
> and switch to GLSL rendermode, every point becomes a VERY large sphere and
> the system slows to a crawl.
>
>
>
> - When a wireframe is rendered in Tachyon the lines are of course replaced
> by thin cylinders. This works out nicely in the CPU-only Tachyon
> (particularly if I use a transparent material, yielding a nicely
> unobtrusive mesh), but the cylinder diameter is much larger in
> Tachyon-OptiX. Is it possible to shrink this, or is this one of the
> trade-offs that allows the renderer to be so blazingly fast?
>
>
>
> - When using the interactive renderer, closing the rendering window with
> the mouse rather than pressing Esc or q crashes VMD.
>
>
>
> - I think it would be awesome if the interactive renderer had an option to
> render the scene at some multiple of the screen resolution, for when
> poster-quality images are needed.
>
>
>
> Cheers,
>
>
>
> Tristan
>
> 

-- 
NIH Center for Macromolecular Modeling and Bioinformatics
Beckman Institute for Advanced Science and Technology
University of Illinois, 405 N. Mathews Ave, Urbana, IL 61801
http://www.ks.uiuc.edu/~johns/           Phone: 217-244-3349
http://www.ks.uiuc.edu/Research/vmd/