Troubleshoot deformation
 
 
 
When I paint/alter settings on the deformer for my mesh, nothing seems to happen and I am still getting old deformation.

Check to see if you have the cache attribute set to read-node or read-file. When the cache mode is set to read-node or read-file, you do not see changes to the deformer since it is effectively only using the cache for deformation. First, set the cache attribute to disabled to make it update.

Can I cache negative frames?

Yes. The Muscle deformer allows for up to 1024 negative frame values. This is also why the output to file caches are offset with an additional 1024 added to the actual frame number saved.

Can I use sub-frames?

Yes. Muscle properly deforms on subframe intervals, even when using cache data. Cache data is linearly interpolated between cache frame information.

What is the difference between the Relax and Smooth weights?

Relax can at first appear similar to Smooth, but they are different. Relax weights cause the mesh to attempt to get back to a more original state keeping points more or less where they used to be, which can also cause wrinkling. Smooth weights actually smooth the points out, not caring about the original point location. Typically, Smooth brings points closer together and loses detail, while Relax moves points closer or farther depending on what is needed.

Do you have any tips for the Relax feature?

Relax can be a slow calculation. You usually want to turn this on only at the end of your work before rendering. When painting or setting Relax weights, you can disable the entire deformer by setting the envelope to 0. In addition, if you are going to preview an animation with Relax, it is recommended that you turn it on, then generate a cache of your animation sequence to play it back from any angle at a faster speed. See Create a cache.

In most cases, the new wrinkle or pull modes work best. This helps relax out muscle sliding effects without wrinkling. You can use the separate Wrinkle weights to get wrinkle effects. normal mode can cause a popping-wrinkling effect which may be undesirable.

For overall smoothing, you can also use Smooth weights. You can use Relax to get wrinkles with painted wrinkles and wrinkle mode active, then use Smooth weights and smoothing to do more of a true smooth deformation.

Do you have any suggestions for using Shrink Wrap?

Shrink Wrap slows down your sliding effects. You can use it for a modeling feature, but it is recommended that you turn off Shrink Wrap for actual rigging purposes. In addition, a similar effect can be achieved by simply modeling your geometry smaller or inside the muscles, instead of outside. That is, instead of making your skin mesh larger and surrounding your muscles, make it smaller and use regular sliding without Shrink Wrap to get a very similar effect.

I can't apply a blendshape to my mesh after Muscle has been applied.

Make sure you have deleted any cMuscleDisplay shape nodes. For example, you can do this by running the following MEL command:

delete `ls -type "cMuscleDisplay" "*"` ;

This deletes all cMuscleDisplay nodes. After that you can apply a blendshape deformer. Opening the Muscle Paint window again recreates these nodes, but they are automatically removed when the dialog is closed properly.

Smart Collide deformation doesn't seem to work with Maya skinClusters being used underneath Maya Muscle.

If you are using Muscle above a skinCluster, use the Relative mode for deformation. This is needed even if you are not skinning with actual Sticky weights. Switching to use Relative mode (see Relative Sticky deformation) causes the Smart Collision routines to work properly when a skinCluster is used below Maya Muscle.

Muscle Self Collision sometimes pops on and off.

The Self Collision algorithm can sometimes appear to disable if the collision areas are too complicated. This can also happen based on how large the collision area is. In many cases, you can simply paint "0" value collision weights on the backs of areas you do not need to collide and this can help resolve these issues, as well as speed up the calculations. For example, on an arm, you can paint a large section on the back of the elbow as black (or 0) to help it solve properly when the front of the arm collides. Another solution is to use the Muscle Smart Collide nodes which are both faster and more stable than fully automated self collision. (See cMuscleSmartCollide node.)

Is there a reason to delete Muscle Jiggle Cache, Per-Point Skin Jiggle Cache or Node Cache?

Yes. First, if you are referencing a rig, and the rigger has test animated the muscles in the rig, you may get an error reloading an animation file. This is because both the rig and the animation file are attempting to store muscle Jiggle information. To fix this, see Delete a muscle Jiggle cache.

In addition, if you have animated a shot and plan to do a node or external file cache for speed during lighting, rendering, or playback, there is no need to keep that data or per-point skin Jiggle data, since you have already effectively cached every point. Deleting per-point skin Jiggle data saves a lot of disk space when saving the scene. If you do not delete the per-point skin Jiggle cache your Maya files may become large.

Deleting the Node Cache can also help reduce file size, if you have decided the cache is bad or you do not want to use it anymore. You can also cache to an external file instead. (See Delete a node cache.)

Is there a way to mirror muscles from one side to another?

For new muscles built with the Muscle Creator window, you can copy/paste or mirror muscles after they are created. See Mirror muscles.

If you use the older Muscle Spline deformer, it is recommended that you use the Mirror option found in the Finalize tab of the Muscle Builder window as you build simple muscles. You must have proper naming on your Attach objects and on the muscle for this to work. Mirroring must occur as you create the muscle.