dvfedele
Oct. 3, 2011 19:04:21
I'm trying to make an otl for a deformer that is aligned with the objects normal.
It will act similar to maya's softmod and have it's pivot follow a point of my choice.
How can I get the handle to align to the surface normal of the object I wish to deform?
My object will be animated on the sop level and I've tried various things that only seem to work with obj level transforms.
tried this method too:
point(“/obj/sphere_object/sphere1”,4,“P”,0) + vtorigin(“”, “/obj/sphere_object”)
point(“/obj/sphere_object/sphere1”,4,“P”,1) + vtorigin(“”, “/obj/sphere_object”)
point(“/obj/sphere_object/sphere1”,4,“P”,2) + vtorigin(“”, “/obj/sphere_object”)[2
edward
Oct. 4, 2011 09:36:51
I'm not sure I understand. In Houdini, there is a strict separation between the “object” (the scene transformation) nodes and the “SOP” (geometry) nodes. As such, it doesn't make a lot of sense to talk about the “normal” of an “object”.
To get a normal from your geometry, you need to get it from a geometry (SOP) node, or “/obj/sphere_object/sphere1” in your example. Normals are usually computed as the attribute named “N” (as opposed to “P” for position). Note also that normals are not computed by default. To do so, append a Facet SOP to your sphere node and enable “Post-Compute Normals”.
Finally, I'm not sure what maya's softmod tool does exactly, but have you tried the
Soft Peak [
sidefx.com],
Soft Transform [
sidefx.com],
Bulge [
sidefx.com], or
Magnet [
sidefx.com] tools? Note also that the Soft Transform functionality is also available in the default
“Move” [
sidefx.com] tools.
dvfedele
Oct. 4, 2011 16:50:52
Sorry about my terminology when referring to the normals.
I'm familiar with the Soft Transform tool and it does what I like.
I want the Soft Transform node's pivot to follow the animation of a provided point. Almost akin to a pin constraint.
Then I want the Soft Transform's handles to be aligned with the geometry normals so that the z axis points in the geometry normal direction.
That way I have a tracking Soft Transform pivot that follows the geometry normal and properly rotates when there is a obj/sop transformation.
I've attached an example illustrating the problem.
Thanks Edward!
edward
Oct. 5, 2011 09:48:12
Offhand, I don't think you can with Soft Transform.
dvfedele
Oct. 10, 2011 12:49:52
Can you recommend another way to approach this if I can't offset the handle?
Thanks!