Move SRT values of Local and Global Matrices - how?

[Draise]

I found a Transform Mesh node. But it moves the point positions (pretty cool trick). But I need to move the center/object entirely, not it's mesh.

Now, when I try Get and Set Local and Global SRT data, I can't.. seem to set it. It goes red. It says the source is not set. Though.. I set it.

Can you directly drive SRT values of a null or mesh or something with ICE without modifying point position or using pointclouds?

[Draise]

I guess I can use a cube as a "ICE mesh transform" then constrain a null to a cluster on the transformed with everything attached to it, so that I can then bake the animation of the constrained null for FBX rigs I suppose - then just hide the cube?

[NNois]

Hi,
You can ONLY write the global transform matrix, so for example build a tree like this:

-> SRT to matrix -> set data self.kine.global -> execute

[Draise]

Only global?! Is there no way to get the local to drive another local?

[NNois]

you can only write the global, yes.
but nothing prevents you to work in local by calculating it, getting the "parent global pos".
-> get data "this_parent.kine.global" (this_parent is the magic part here)

[dwigfor]

Hi Draise,
Hopefully this helps you understand 3x3 Matrix, local vs global, parenting -
http://www.si-community.com/community/v ... kinematics
-Dave

[Draise]

ICE kinemetics! That's the term I needed to google for! Thanks for that. I'll study them promptly.

I found a way of using nulls or whatever constrained to a mesh "null" cluster and driving mesh points with ICE transform and scalar and 3x3 vectors - that worked.

[dwigfor]

"linear algebra" would be another good search term that will help you immensely with ICE kinematics and just help understanding 3d math.

Another old thread of mine might help; converting code from games for ICE -
http://www.si-community.com/community/v ... code#p7416

On that thread, I had 2 links which are VERY helpful for understanding matrix.
http://www.andynicholas.com/?p=861
http://www.andynicholas.com/?p=911

And this is fantastic! (Yes! I found it!! It still exists!) Todd Akita's ICE Survival Guide -
http://area.autodesk.com/userdata/blogs ... _Tools.pdf Links on si-community were old; this one works!

Have fun!

[Draise]

The ICE kinematics tutorials you made are excellent. And I also learnt how to make custom ICE attributes that I can set in one tree, then use them drive data in other trees (albiet in Simulated ICE trees?) - which answered another quesition I had posted earlier. You're a genious, thanks for being so helpful.