Adding a Blend to Overlapping Clips
Partially overlapping clips create additive animation during the frames when the two clips overlap. The trouble with the overlapped section is that the animation can pop when the new clip is introduced because the values of the animated channels suddenly change.
To resolve the popping problem, you can add a blend to the clips, creating a smoother alteration from the values of one clip to values of the other. To create a blend, Shift+select the two clips and, with the cursor over one of the clips, RM choose Blend. The overlapping area of the clips will turn green, and an arrow showing blend direction will appear between the clips, as in Figure 10.14.
Blending works using the common attributes of the two clips. Blending will not be effective if the clips you are trying to blend do not share common attributes. Also, blending will create a smoother transition if a similar motion is maintained between the two clips.
In the Trax Editor, choose Create ■ Blend □. Look at the options in the Initial Weight Curve and Rotation Blend sections. In the Initial Weight Curve section are four choices that give you control over the tangents used to create the blend.
Linear Creates an evenly weighted transition between the clips.
Ease In Assigns less weight at the beginning of the transition and increases the weight given to the next clip as frames in the blend progress. This makes the beginning of the transition less noticeable.
Ease Out The opposite of Ease In; places more weight on the beginning keys. The effect of the first clip is more prominent than the effect of the second clip for a longer amount of time.
Ease In and Ease Out Combines the Ease In and Ease Out options.
- Figure 10.14 Two animation tracks blended
You will discover that you achieve different results with each option. To remove a blend so you can experiment with other settings, select the blend arrow and press the Delete key.
The items in the Rotation Blend section control how the rotation attributes from the first clip are combined with the rotation values of the second clip (assuming, of course, you have rotation keyframes animated). Quaternion Shortest uses the least amount of distance between the rotations, and Quaternion Longest uses the greatest distance between the rotations. Basically, if you don't want the object to spin in the opposite direction as one clip blends into another, choose Quaternion Shortest. The Linear option merges the rotation values at a constant rate during the blend. Experiment with these options to see just how big a difference each choice will make. Once you are familiar with the way the blend works, you will more easily achieve a successful transition between the clips.
Post a comment