Jump to content

Why constraint_type = all is different from position and rotation combined?


Recommended Posts


I been playing houdini constraint recently. I find the behaver of bullet hard constraint is not very easy to predict, especially combined with condof, condir, position, rotation and angular motor.

I have an simple file as an example.

One box hard constraint to world space.

Using one wrangle node with s@constraint_typle = "all". it works as expected. Box stay there.




When I split constraint with position and rotation. Give them all condof = 3. Ideally it should be act same as the last one stay there (I assume), but box start to fall. I tried constraint force mixing and error reduction parameter it can improve but I'm not sure I should do that since this is super simple setup shouldn't use too much tweak.







I'm working on pretty complicate rigid constraint setup I need to fully understand the bullet constraint behaver.  Really appreciate the help. 


I also want to ask is rbd constraint the better way for complicated rigid body constraint with lots gear and mechanical parts and vellums. 




Edited by bbrcn
Link to comment
Share on other sites

12 hours ago, vicvvsh said:

If you set physical parameters back to default values on /obj1/dopnet14/rbdpackedobject1 behavior of constraints is fine. Don't ask me why, I don't know, maybe a bug.


Cool, thanks

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...