Page 944 - Kitab3DsMax

Part VIII: Advanced Animation Techniques
The Select Keys by Time utility lets you select all the keys within a given time block by entering the frame
or time values. To use this utility, click the Track View Utilities button or select the Utilities ➪ Track View
Utilities menu command to open the Track View Utilities dialog box, and choose the Select Keys by Time
utility from the list. Then in the Select Keys by Time dialog box, enter the Start and End values to complete
the selection.
Deleting, cutting, copying, and pasting time
After you select a block of time, you can delete it by clicking the Delete Time button. Another way to delete
a block of time is to use the Cut Time button, which removes the selected time block but places a copy of it
on the clipboard for pasting. The Copy Time button also adds the time block to the clipboard for pasting,
but it leaves the selected time in the track.
After you copy a time block to the clipboard, you can paste it to a different location within the Track View.
The track where you paste it must be of the same type as the one from which you copied it.
All keys within the time block are also pasted, and you can select whether they are pasted relatively or abso-
lutely. Absolute pasting adds keys with the exact values as the ones on the clipboard. Relative pasting adds
the key value to the current initial value at the place where the key is pasted.
You can enable the Exclude Left End Point and Exclude Right End Point buttons on the Extras toolbar
when pasting multiple sections next to each other. By excluding either end point, the time block loops
seamlessly.
Reversing, inserting, and scaling time
The Reverse Time button flips the keys within the selected time block.
The Insert Time button lets you insert a section of time anywhere within the current track. To insert time,
click and drag to specify the amount of time to insert; all keys beyond the current insertion point slide to
accommodate the inserted time.
The Scale Time button scales the selected time block. This feature causes all keys to be pushed closer
together or farther apart. The scaling takes place around the current frame.

Setting ranges
The Position Ranges button on the Ranges toolbar enables you to move ranges without moving keys. In this
mode, you can move and scale a range bar independently of its keys, ignoring any keys that are out of
range. For example, this button, when enabled, lets you remove the first several frames of an animation
without moving the keys. The Recouple Ranges button can be used to line up the keys with the range again.
The left end of the range aligns with the first key, and the right end aligns with the last key.

Editing Curves

When an object is moving through the scene, estimating the exact point where its position changes direc-
tion can sometimes be difficult. Function curves provide this information by presenting a controller’s value
as a function of time. The slope of the function curve shows the value’s rate of change. Steep curves show
quick movements. Shallow lines are slow-moving values. Each key is a vertex in the curve. Function curves
are visible only in the Curve Editor and the Track Bar layout.

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