Parent Switching and Blending

[darkjedi1929]

Yeah, well, that is supposed to happen. Correct me if I am wrong here, when you constrain an object to another, it just stores the offset values of the object at the point where it's constrained and then using those offsets, drives the rots and translates. Therefore is you have two parents, there will be a "POP" when you shift parents. The simple solution is this: if you are shifting from parent A to parent B, first move parent B to parent A's position (use the xform command, preferably) and then change the attribute. You can also write a MEL to do this whole thing in the background...

Hope this helps.

[backwheelbates]

Thanks DarkJedi1929. That worked pretty well. I just melscripted A(WorldSpace) locator to lock to the position/orientation of B(RobotSpace) locator until the control is switched back to A locator. I left B locator alone because its constrained already to the character's main body. It works great going forward in the timeline, but because the scripting/position is dependant on B's previous position, it doesnt really work to scrub back and forth. Its not a perfect solution, but I think it will work for this situation.

Thanks again,

Eric

[StephG]

What I would recommend is to make a control window where you switch between parenting states. The control switch would run a script that looks something like this:


float $pos[] = `xform -q -ws -t "ObjectName"`;//gets the current position
float $rot[] = `xform -q -ws -ro "ObjectName"`;//gets the current rotation

setAttr "ObjectNameParentConstraint.weightattribute1" 0;
setAttr "ObjectNameParentConstraint.weightattribute2" 1;

xform -ws -t $pos[0] $pos[1] $pos[2] "ObjectName"`;/*puts the position before switch back on the object*/
xform -ws -t $rot[0] $rot[1] $rot[2] "ObjectName"`;/*puts the rotation before switch back on the object*/


I used to use scriptJobs for this, but they're notoriously annoying when you scrub backwards and the switching attribute changes, especially if you have autoKey on.

Making a control window also works much more reliably when you have a multi character situation, if you have all the characters in the scene listed in a textScrollList or pulldown menu.

[darkjedi1929]

Thanks DarkJedi1929. That worked pretty well. I just melscripted A(WorldSpace) locator to lock to the position/orientation of B(RobotSpace) locator until the control is switched back to A locator. I left B locator alone because its constrained already to the character's main body. It works great going forward in the timeline, but because the scripting/position is dependant on B's previous position, it doesnt really work to scrub back and forth. Its not a perfect solution, but I think it will work for this situation.

Hmmm....to make it interdependent, how about grouping B to itself, moving this new group's pivot to B, and then applying the method? This seems to work fine for me.

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