Saving and Loading Animation

You can save and load animation data for any number of objects separately from the actual scene via Load Animation and Save Animation commands available on the Animation menu.

These commands use two file types:

• XAF (XML Animation File) contains the animation data.
• XMM (XML Animation Map File) contains mapping information: how the incoming animation data is assigned to objects in the current scene.

Mapping is quite flexible: As long as data is comparable, it can be assigned. For example, each key for both position and rotation animation contains three numbers, so you could, if you wanted, assign incoming position data to a current object's rotation track, or vice versa.

Procedures

To use the Save Animation and Load Animation commands:

You start by saving animation data from the current scene.

1. Select any number of objects in your scene that contain animation. The animation can be of any type: procedural, manually keyframed, IK, and so on.

   The frame range from which the animation is saved is the same for all objects, so make sure you select only objects from which you want to save the same frame range.

   Note: Using this method, you can save animation only from selected objects. Alternatively, you can save animation from specific tracks in Track View; see Hierarchy Right-Click Menu.
2. From the Animation menu, choose Save Animation.
3. Set the save parameters.

   By default, the command saves all keys from animated tracks for selected objects, including motion derived from constraints. For example, if an object rotates because a LookAt constraint is applied to its Rotation track, then when you save its animation with Include Constraints on, 3ds Max generates rotation keys based on the constrained motion. It does not save the actual constraint.

   You can save just a part of the animation by turning on Segment and setting a frame range.

4. Specify a file name and then click Save, or click the + button next to Save to increment the file name and save under the new file name.

   If the selected objects contain no savable animation, the message “No animation tracks to save” appears. If this happens, create animation to save or change the Save Animation parameters as needed.

   Next, you load the animation data.

5. Set up or load a new scene and then select any objects that are to receive the loaded animation.
   Note: Using this method, you can load animation only to selected objects. Alternatively, you can load animation to specific tracks in Track View; see Hierarchy Right-Click Menu.
6. From the Animation menu, choose Load Animation.
7. Find and highlight the XAF file from which to load animation.
8. Click Load Motion. If the objects you're loading animation to are the same as those you saved the animation from, the animation loads and is mapped automatically. If mapping is required, you're given the opportunity to set it up. Or, if you've already set up mapping for the scene and incoming animation data, choose a mapping (XMM) file from the Motion Mapping/Retargeting drop-down list and then click Get Mapping. Otherwise, click Edit Mapping.

   Clicking Edit Mapping opens the Map Animation Dialog, which contains three lists: from left to right, Current, Mapped, and Incoming. The Current list shows selected objects in the scene and their animation tracks; the Incoming list shows animation tracks in the XAF file, and the Mapped list shows, for each track in the Current list, the animation track in the Incoming list that will map to it. In certain cases, such as with objects that have the same name, some tracks are mapped automatically and appear in the Mapped column as soon as you open the dialog. The tracks that are already mapped are shown in gray in the Current and Incoming columns.

9. To map a pair of tracks manually, click a track in the Current list and another in the Incoming list, and then click the left-arrow (<-) button to the left of the Incoming list.

   This places the name of the incoming track in the Mapped list, opposite the Current-list track to which it is assigned.

10. To remove a mapping assignment, click its entry in the Mapped list, and then click the -> button.
11. Continue setting up the mapping assignments as needed. When you're finished, click Save Mapping or Save Mapping As, and then specify a file name to save.

    After you save the mapping file, the Load Motion button becomes available, and you can proceed with loading the animation.

12. Click Load Motion.

    The animation data is loaded and assigned to the selected objects, and any animation keys appear on the track bar.

To retarget an incoming animation:

This is a continuation of the previous procedure, and explains the basic workflow of node retargeting. Retargeting means to scale the animation so it matches the objects onto which you are mapping the motion. You can use this feature any time you need to transfer an animation between two objects or rigs of different sizes and proportions. For example, an animation of a cat stretching could be retargeted to a bigger dog model, resulting in a scaled animation to fit the dog's skeleton.

Once your track-mapping assignments are complete, the Retargetable Nodes list on the Retargeting rollout displays the mappings available for retargeting.

For steps that describe retargeting a character rig, see To retarget one character onto another.

1. First, in the Scale Origin group, choose the Incoming and Current objects to use as the origin and basis for scaling.

   For example, when retargeting a rig, you would use each rig's root object.

2. Next, in the Derive Scale Between Chains group, chose comparable IK or FK chains from the Incoming and Current models to obtain a Scale Factor that proportionally retargets the incoming animation onto the current model.
3. Click Set to apply the retargeting.
4. If different portions of the model are differently proportioned, you might need to repeat steps 2 and 3 for different selections of mapped tracks. You might also need to use the FK Retargeting Extent group to account for the different proportions. See Retargeting Rollout for more details.
5. When you're finished, save your mapping to preserve the retargeted data, and then click Load Motion to apply the animation to the currently selected objects.

   Retargeting is essentially a “by hand” process. You might need to try different settings to get the result you need. You can remove retargeting by highlighting a mapped track in the Retargetable Nodes list, and then clicking Clear.

6. Close the Map Animation dialog.