Choosing a Shape Instance Mode for Shape Clips
Shape instance modes determine how the shape clips are instantiated when they are added to the animation mixer. This is applicable when you store and apply shape keys (see Storing and Applying Shape Keys), create shapes in the shape manager (see Using the Shape Manager), apply them after selecting them (see Selecting Shape Keys), but not when you apply them (see Applying Shape Keys), load, or drag them into the mixer.
There are five modes that affect what happens when shape clips are created: Mixed Weight, Blended Weight, Standard Transition, Cardinal Transition, and Instance Only. Each mode affects how the shape clips are created in the mixer, their length, and their placement on the tracks. For example, in Mixed Weight and Blended Weight modes, shape clips automatically take the full length of the scene.
To set the default shape key mode
1. Choose Deform > Shape > Preferences from the Animate toolbar or File > Preferences from the main menu.
2. In the explorer that appears, select Shape Animation or click its icon.
3. Select one of the Shape Instancing Mode options, described here.
Once you store and apply a shape, you cannot change the shape key mode for that cluster.
The Mixed Weight mode (the default mode) creates shape clips that are the same length as your scene (you can always change the length of the clips as you like later). This mode is also compatible with working in the shape manager.
These clips are created on separate tracks with default weight curves. This is useful if you want to control shapes by mixing the weights of different shapes instead of transitioning from one shape to another, as you can with either the standard or Cardinal transition modes.
When you store and apply shape keys in this mode, a Shape Weights custom parameter set is created for the object to help you mix weights easily. For more information on this, see Mixing Shape Weights in a Custom Parameter Set.
The Blended Weight mode is the default mode for working in the shape manager. In the same way as the Mixed Weight mode, this mode creates shape clips that are the same length as your scene (you can always change the length of the clips as you like later). However, the shape weights for each clip don’t have fcurves automatically created for them.
For information on the shape manager, see Using the Shape Manager.
Standard and Cardinal Transition Modes
The Standard and Cardinal Transition modes both create shape clips that are zero frames long: they represent a transition point. The clips are instantiated on the same track, and transitions are automatically generated between them, making it easy to create a simple shape sequence. Each transition has a curve that you can edit in the animation editor.
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• The transition curve on the clip controls the shape clip’s weight in time, not the shape of the Cardinal transition in space. • The Standard and Cardinal Transition modes are not compatible with working in the shape manager. If you have shapes created for an object in these modes, you need to first delete its shape clips before being able to work with it in the shape manager. See Creating Shapes for more information. |
If you create a number of deformed objects and select them as shape keys for an object, these modes makes it easy to create transitions between them, rather like a pose-to-pose type of animation.
You can create the same transitions between shape clips manually using the Mix > Standard Transition or Cardinal Transition commands in the mixer. For more information, see Creating Transitions between Clips.
• Standard Transition mode creates transitions with a linear interpolation in space, moving directly from one shape to the next. The results are a more mechanical-looking transition than found with Cardinal.
• Cardinal Transition mode creates transitions with a Cardinal interpolation in space, resulting in a smooth, arcing curve that still passes through each shape key at the defined key frames.
You need at least four shape clips for the curve to be fully Cardinal, but three shape clips will give you a bit of a curve too. The interpolation on any segment is influenced by the four nearest shape clips.
The Instance Only mode creates shape clips that are 10 frames long, making it easy for you to resize them as you like in the mixer. They are instantiated on separate tracks within a compound shape action. Because the clips are 10 frames long, they will mix with each other if you set keys that are less than 10 frames apart—of course, you can adjust this in the mixer.
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The Instance Only mode is not compatible with working in the shape manager. If you have shapes created for an object in these modes, you need to first delete its shape clips before being able to work with it in the shape manager. See Creating Shapes for more information. |
In the mixer, you can scale the clips to any size then manually add transitions or mix weights. You can scale a clip down to one frame interactively by dragging its edges.
To scale a shape clip to zero frames, right-click it then choose Time Control and set the Source Clipping In and Out values to 0.
To see the name of a zero-frame clip, make sure that Tooltips is active on the Clips page of the Animation Mixer Preferences dialog box and hover the mouse pointer over a clip to see its name pop up. For more information about the mixer view preferences, see Displaying Mixer Elements.
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