Simulation, surface generation etc using command line

[Ankit Pruthi]

Here goes my first post in this forum. I've started to learn houdini recently and I am in love with it so far

Before I start with the actual problem, i wanna say that i have searched the help file and forum too but couldnt find any solutions.

And here goes the question. Is it possible to use command line to simulate dynamics in houdini 11 apprentice?

I was trying out FLIP fluids the other day. And while experimenting with it, i ended up with a very heavy geometry being generated while surfacing.

The issue i'm facing is that since its a very heavy mesh, i run out of ram midway (i've only 4 GB). And then system starts using swap and crawls.

I realized that houdini takes up around 2.5 gb ram just to load up the scene alone. So i was wondering if there is a way to generate the surface using command line so that i can finish it without having to open the scene? In fact not just generating surface, but any kind of DOPs and POPs etc too.

If not, i guess i'm gonna have to do with fewer particles and much coarser mesh or wait for hours while my system crawls begging for mercy.

Thanks for your time!!

[old school]

If you can open up a shell, source in the Houdini environment and then see if you can run hscript and it is successful, then yes you can run Houdini non-interactively.

You can always disable all caching on the DOP network node and use a desktop that doesn't have a viewport present to minimize the amount of memory consumed. You can run Houdini at start up with any desktop you wish with the -s option:

houdini -s textport /path/filename.hip

will launch Houdini on the given scene file with the textport up and ready to use. This means nothing has cooked/evaluated. Just don't do an iinfo on a node to trigger a cook. If you have a ROP output driver set up to generate the geometry to disk (hint, hint...), just use the hscript "render" command to execute the render and trigger the authoring of files to disk. Just make sure to disable all caching on your DOP sim and remember render flags are used in place of display flags.

If this is Windows, then you can create a new shortcut to your application then change the execute command from houdini to houdini -s textport so that this "specific" shortcut will launch houdini using the textport as default. Give it an appropriate name and to launch your file with this shortcut, do the windows thing and rmb then choose that shortcut to launch that app.

Here's the help usage for Houdini btw with all the command line flags available for you to exploit:

houdini -h

$ Usage: houdini [-foreground] [-geometry wxh+x+y] [-h] [-f] [-j nproc] [-s editor] [filename ...]

-h: output this usage message

-f: force the use of asset definitions in OTL files on the command line

-j: set maximum processors to nproc

-s: specify starting desktop by name

-n: start up in Never cook mode

-foreground: starts process in foreground

-geometry: specify window width, height and x and y offsets

Edited November 2, 2011 by old school

[Ankit Pruthi]

Hey sorry for not being able to reply earlier but thanks for the quick response. This worked like a charm and using shell was twice as fast to generate all the surfaces etc!

[NicoZ]

Very interesting, thanks for the explanation.

[kursad]

If you have a ROP output driver set up to generate the geometry to disk (hint, hint...), just use the hscript "render" command to execute the render and trigger the authoring of files to disk. Just make sure to disable all caching on your DOP sim and remember render flags are used in place of display flags.

Here's the help usage for Houdini btw with all the command line flags available for you to exploit:

old school,

Do you know if there are any "render" command options or arguments on the commandline? I guess it would be great if we can render with much verbose output. Selecting "alfred sty;e" in the rop does not give a real verbose output about what is going on with the render.

thanks

[ikarus]

old school,

Do you know if there are any "render" command options or arguments on the commandline? I guess it would be great if we can render with much verbose output. Selecting "alfred sty;e" in the rop does not give a real verbose output about what is going on with the render.

thanks

use the -v flag