If you want to use cloth or soft body on an envelope or use it with another type of deformation, you should apply cloth or soft body to the envelope or object before you apply the envelope to a skeleton or use another deformation.
This is because of the order of operators for the object: if cloth or soft body is applied after the envelope, it doesn't know that the envelope exists (the Cloth or SoftBodyOp operator is above the Envelope operator in the stack) so it won't deform properly.
Of course, if you do apply cloth or soft body after the envelope, it's still simple to move the operators in the construction history to get the correct results.
Applying Cloth or Soft body Before the Envelope
To apply cloth before envelopes or other deformations
Parent the object you want deformed to the bone (or deformer) that matches the movement that you want the cloth or soft body object to inherit.
Select Animation from the Construction Mode list on the main menu bar at the top of the interface.
This keeps the ClothOp or SoftBodyOp operator in the object's Animation region in its construction history so that Softimage knows you want to use the cloth or soft body as an animated deformation.
For general information on construction modes and the viewing options related to these modes, see Construction Modes and Regions [Modeling and Deformation Basics].
Keeping in Animation mode, apply the envelope or deformation to the cloth or soft body object.
For more information on envelopes, see Envelopes [Character Animation].
For information on deformations in general, refer to Deformations [Modeling and Deformation Basics].
Applying Cloth or Soft Body After the Envelope
If you apply cloth or soft body after the envelope is applied to the skeleton, or after another deformation is applied, the envelope or object doesn't deform properly because of its order in the object's construction history. If the envelope or deformation is applied after cloth or soft body, then the cloth or soft body operators don't know that it exists.
To fix this, simply drag the Envelope or other deformation operator in the explorer so that it's above the ClothOp or SoftBodyOp operator, as shown below. If you do this, the envelope or other deformation is applied first, and then cloth or soft body can be calculated in relation to it.
Another useful thing to do is to disable any operators above the current one. To do this, open an explorer, right-click on the lowest envelope or deformation operator you want to disable, and choose Disable from Here. The operator and everything above it no longer affect the object.
For more information about using the operator stack, see Operator Stack [Modeling and Deformation Basics].
