Hello,


how do I get Fast_Mantra and Mantra-sel in my scene (ROP). I can only get MANTRA via Tab>Generator>Mantra.
What is the difference between Mantra, Fast_Mantra and Mantra_Sel? (seen in ROP when opening Houdini 7)



thx


bernard

Take a close look at them - really there's nothing special about them except they have different parameters. They're just a couple of convenient presets that also educate a little. Fast Mantra has a lower sampling level, Mantra_Sel has a parameter in the Visible Obects to only render what's selected.

If you've deleted them from the file you're working on, just fire up a new session, select the two, Ctl-C to copy, then flip back to your current hip file and paste into the ROP section.

Cheers,

J.C.

Or, you could take a look at how fast_mantra and mantra_sel are configured, see what those parameters do and really understand what is going on in there, I think it will help. And check out Rendering with Mantra5 VTM too:

http://sidefx.vislab.usyd.edu.au/houdini_video/by_topic/rendering/index.html [sidefx.vislab.usyd.edu.au]

You can always reload the 123.cmd script that is run by default when houdini starts up fresh.

Open a textport. Type in:
source 123.cmd
Now this will also load in the default three lights, model object and camera. Just delete these and you are done. For those not in the know, you can edit 123.cmd to load whatever you want on fresh startup. You can add a 456.cmd script file that is run whenever Houdini launches, opens files, etc. It is run all the time.

If you don't want to do the quick source method, you can also simply change the parms on two mantra output drivers that you add. A couple simple expressions are used and chaning a couple default values should do the trick.

fast_mantra

• Super Sample: 2 2
  
  
  mantra_sel
  visible objects: (`opselect(“/obj”)`)
  Super Sample: 2 2
  res: 320 243
  The expression opselect() simply returns a space delimited list of all the selected nodes in the directory /obj. Yes, even if you have cameras selected this script will return that but fortunately only objects will be identified and used in this particular string field. And yes, because this is a string field, you need to use backquotes around the expression to force it to evaluate as string fields don't like to evaluate expressions all the time (at all really).
  
  That's it.

Thanks for the great info!



bernard