Dustin Tarr

Hi,

I know this post is a bit old but I am messing around with rendering in Mantra with Houdini 16.5.571. I cannot seem to get the Indirect and Direct passes to work correctly for any export components. If you check Direct and Indirect passes it is putting everything into Indirect and nothing goes into Direct. I have turned all of my limits above 1 or a little more just to be sure there were multiple bounces but still, direct pass is empty and it is all fed into indirect. Is this a bug or just the way mantra works now or am I missing something (potentially something very simple that I am overlooking)? I used Mantra before in past versions and it worked fine. I have tried this in a couple different builds as well. (I know was build 16.5.496) Any help is appreciated, thanks!

So I got it to work due to my coworker coming across Rohan Dalvi's recent tutorial [vimeo.com] that I missed where he is able to get it to grab an object and release it.

I was able to use the vellum constraint property node to release it more manually using vex but it is a bit frustrating that to have the object grab the cloth it has to be an actual vellum object within the simulation where the cloth could potentially collide with it. If anyone finds a way to get it to work without the glue object being able to collide with the cloth or vice versa please do not hesitate to post. I will post an example file below of my simple test just in case it is useful to anyone.

Hi all,

I have a Vellum issue I am trying to figure out and not seeing much documentation or information on it out there. I also posted on ODForce so I will link and quote the post below in case the solution comes up in there.

Link:
https://forums.odforce.net/topic/41347-vellum-dynamic-constraints-question/ [forums.odforce.net]

Issue:
“Hello houdini wizards!

I am playing with Vellum and trying to get the dynamic glue constraints to work. The documentation is about 1 very small section and I did what it said to (like creating the glue inside the solver and setting the Create Constraints drop down to Each Frame) but it does not grab the cloth. I played with distances and groups but no luck.

I don't have a specific scenario at the moment so no scene file really that cant be set up in 2 minutes, just a grid as the cloth object, a sphere (fed into the collision input at the sop level) that dips down close the grid and then moves back up. The intention is to have constraints be created to grab the cloth within the set distance, pick it up, pull it, and then release/break the constraints when I want/need to. The breaking I can assume is pretty simple using the broken attribute in the Constraint Properties but I cannot seem to dynamically create constraints to grab the cloth/grid. Any help or knowledge you can give is much appreciated!”

I was unable to find any example files on the subject either but I did see the demo of it being done (https://vimeo.com/313872854) around 24:50. And again, thanks in advance for any advice you can give!