Tuesday, 22 November 2011

Remember remember

Not the 5th of November, Constraining!

Just had to figure out how to constrain objects to things (characters mainly) because, well, you forget if you don't do it for a while. Last time I constrained something was somewhere around this time last year. So I'm writing it down here in hope that I won't forget again (or at least if I do, I can come back here!). I even changed the colour of the important bits!

I was trying to attach one end of this box to Malcolm's hand because he's going to carry it. I will have to animate the constrain to unattached it when he comes to letting go of it. But we'll cover that another time.

Firstly I was trying to constrain it by Constrain > Object to Cluster but it wasn't letting me pick any cluster I created or any geometry to create a cluster to attach it to. I enquired the legendary facebook group TagerTalk for advice as I remember it was a fiddly thing to do so perhaps I was forgetting something.

To constrain something this way, first you should create a cluster on the geometry in the area you constrain to (pick point(s) Edit > Create Cluster or Ctrl + L), then create a null and Constrain > Object to Cluster. If the geometry cannot be selected (as was in my case), create a small point cloud (2 x 2 or something, depending on how big a cluster you need) parent it to a bone or joint or whatever is appropriate to get the desired movement and then select points and create a cluster.
Then select the object to be constrained and parent it to the null.

I did this and realised it was not what I needed. I needed the box to be able to rotate with the hand and using this method does not take orientation into consideration. Only tranforms!

So I actually needed to Pose constrain. And this is how I did that with the help of my tutor: As Malcolm does not have any selectable bones in his hand, I had to use his main wrist control. Select the object to be constrained. Click Constrain Compensation (CnsComp button under the constrain menu on right). Constrain > Pose. Done!

Malcolm character courtesy of AnimSchool.com

No comments:

Post a Comment