Release Notes Limitations > Clusters

Animating limitations

Limitations related to animation, inverse kinematics, constraints, and clusters.

General

When you use Ungroup with Copy Node option, the new nodes get instances of any animation curves that were on the original nodes. If you then edit the original curves, the new branch is affected as well.

If the above is not what you want, you can create new copies by cutting and pasting the curves in the Action Window.

The grid does not update during a Time Slider scrub when there is a constrained camera.

Turn Optimization off in the Playback Options.

Linear tangents may not work correctly for a Parameter curve with large values.

When the slope of the curve segment between two successive keyframes is greater than 573 - that is, tan(89.9 degrees), linear tangents are not calculated correctly. (AliasStudio truncates the values to avoid numerical errors elsewhere.)

Create the curve on a dummy node with a smaller range of values, and use an expression to scale the value of the curve.

Playing back of visibility animation may put invisible objects on the pick list.

If you pick an object with visibility animation at a frame where it is visible, play back, and then stop playback at a frame where the object is not visible, then the object remains on the pick list, and may be inadvertently transformed or deleted.

Use Pick > Nothing to ensure there are no invisible objects picked.

Viewframe and playback don't update a static expression. For example, if you set an object's X-translate channel to the constant expression "1" and Transform > Move it, it is not reset to 1 by viewframe.

Set a keyframe for these values instead, or use an expression like "1 + frame * 0" instead of a constant expression "1".

The rand() and gauss() functions do not work correctly in expressions if particle emission is occurring.

Turn off particle emission, bake the rand() and gauss() expressions (using the Bake plug-in), and then turn particle emission back on.

Image planes and associated animations are not retrieved correctly if referenced PIX files cannot be found.

Ensure that all referenced pix files associated with an image plane are in place when you save the wire file. If necessary, use a placeholder pix file when saving out the wirefile. If this is not done, the animation associated with the image plane may not be retrievable.

IK and Constraints

UV constraints ignore displacement maps on surfaces.

You can warp the surface for a similar effect, and UV constraints do work with warped surfaces.

Local axes behavior is not consistent if the local axes have not been explicitly set.

If an object has never had its local axes explicitly set, AliasStudio assumes that they are always at a (0,0,0) rotation in object space. So if you watched the local axes while you Zero-transformed the object, for example, the local axes would appear to be transformed as well. However, if you had set Local Axes, AliasStudio does not modify them during Zero transforms.

Certain operations explicitly create Local Axes. For example, skeletons always have Local Axes and Edit > Duplicate Object creates explicit local Axes. Visually, there is no way to tell if explicit Local Axes exist or if the defaults are being used. Therefore, certain tools appear to behave inconsistently with local axes.

Set your local axes explicitly to the desired orientation.

Edit > Duplicate > Object does not remap constraints within the copied hierarchy.

If both the constraint target and destination are in the copied hierarchy, delete the constraint and re-apply it to the new objects in the new hierarchy.

In the Animation > IK > Add IK handle option box, Reset does not reset all the options to their default values.

Reset these options by hand: the default for Orientation is Local, and the default for SetRestPose is Off.

An object with multiple aim constraints may not evaluate correctly.

Aim constraint rotations are restricted to -180/+ 180 degrees; however these restrictions are not enforced consistently throughout the weighting process, so if individual constraints caused rotation values of opposite sign, errors may result.

Use a single object as the aim constraint target where possible. If you really depend on the animation of two separate targets, then point constraining an object partway between the original targets and using this new object may provide an adequate approximation.

Query Edit will not display more than 10 constraints per object.

If you see 10 constraints, check the info window to see if there are any additional constraints that you may have missed.

IK skeletons in layers with symmetry will not be mirrored to the other side of the axis of symmetry. IK skeletons use non-leaf DAG nodes and clusters and these are not supported in layers with symmetry.

Clusters

Splitting a cluster where the members are present at the DAG node level in the cluster editor may cause the geometry to be drawn incorrectly.

If the cluster members are all at the CV level, splitting works correctly. However, if you see an entry in the cluster editor for several surfaces, then some of the geometry will jump to the wrong location when the cluster is split.

The geometry is still there; it's just not redrawn correctly. It will reappear when the cluster transformations are applied again (for example, when the cluster is moved, rotated, etc.).

Transform > Move the clusters by (r 0 0 0) to make the geometry redraw, or expand the cluster members down to their CVs before splitting.

If polyset vertices are placed in a cluster, the vertices themselves will not be drawn when the cluster is picked.

Unpack the cluster to see the vertices again.

Transform > Local > Set pivot of deformation clusters changes the object if there are percentage effect parameters set.

When moving the pivot point on a cluster that has some members' percentage effect parameter set to a value other than 100%, if the cluster has already been transformed with rotations or scaling, transforming the pivot point of the cluster will cause these cluster members to move. (The percentage effects are recalculated for each control vertex according to the new pivot point location.)

This behavior is apparent when clusters are created using the Deformation Control window (Animation > Editors > Deformation control ).

Define and verify pivot point locations for deformation clusters before assigning transformations such as rotate or scale.