Using Soft Body with Envelopes and Other Deformations
If you want to use soft body on an envelope or use it with another type of deformation, you should apply soft body to the envelope or object before you apply the envelope to a chain or use another deformation.
This is because of the order of operators for the object: if soft body is applied after the envelope, it doesn’t know that the envelope exists (the SoftBodyOp operator is above the Envelope operator in the stack) so it won’t deform properly.
However, if you apply soft body after the envelope, it’s simple to move the operators in the construction history to get the correct results.
Applying Soft Body Before the Envelope
To apply soft body before envelopes or deformations
1. Parent the object you want deformed to the bone that matches the movement that you want the soft-body object to inherit.
2. Select Animation from the Construction Mode list on the main menu bar at the top of the interface.
This keeps the SoftBodyOp operator in the object’s Animation region in its construction history so that Softimage knows you want to use 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 ].
3. Apply soft body to the object, making sure to select Use Body Animation and Solid Body Center on the Dynamics page in the SoftBodyOp property editor (see Applying Soft Body to Animated Objects).
4. Apply the envelope or deformation to the soft-body object, also in Animation construction mode.
• For more information on envelopes, see Envelopes [ Character Animation ].
• For information on deformations in general, refer to Deformations [ Modeling and Deformation Basics ].
Applying Soft Body After the Envelope
If you apply soft body after the envelope is applied to the chain or after another deformation is applied, the envelope or object doesn’t deform properly because of its order in the Animation region of the object’s construction history (operator stack). If the envelope or deformation is applied after soft body, then soft body doesn’t know that it exists.
If you do apply the envelope or deformation before soft body, you can drag its operator in the explorer so that it’s above the SoftBodyOp operator, as shown on the left. If you do this, those deformations are applied first, and then soft body can be calculated in relation to them.
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 ].
Autodesk Softimage v.7.5