[Radiance-general] starting rpict -S 1 -P pfile

[Gregory J. Ward]

Hi Lars,

It may just be that you need to use the -PP option rather than -P,  
which doesn't do parallel processing.  (The -P "persist mode" is a  
relatively little-used option that permits serial execution without  
the associated startup costs -- it's more valuable for rtrace than  
rpict.)

Also, each of your rpict -PP commands should be handed the same set  
of views on the standard input.  Otherwise, nothing will happen.

-Greg

> From: "Lars O. Grobe" <grobe at gmx.net>
> Date: October 15, 2005 9:59:06 AM PDT
>
> Hi!
>
> I am currently changing my Makefile that is doing some rendering.  
> So far, the views had been in the Makefile itself, each as one  
> target. Now I wanted to change this and use a viewfile together  
> with the -P option of rpict for multi-processing.
>
> I am wondering now how to understand the manual. I used a line like  
> that:
>
> rpict -S 1 -P pics.pfile -o pic%02d.pic scene.oct < scene.vf &
>
> Because I thought that the rpict process must go to the background,  
> so that I can start the other processes with
>
> rpict -P pics.pfile &
>
> However, I did not get any output. So was the & after the first  
> rpict the problem? Will it read the scene and send itself to the  
> background, waiting for more processes? Or do I simply have to wait  
> before starting the second rpict, until the first one has read the  
> entire scene?
>
> TIA + CU, this multi-processor radiance stuff is really not easy...  
> Lars.
>
> from my Makeile:
>
> pics: scene.oct scene.vf
>     rpict -S 1 -P pics.pfile -o pic%02d.pic scene.oct < scene.vf & \
>     rpict -P pics.pfile & \
>     rpict -P pics.pfile &