GDT 260 Animation for the Web: Winter 2002
2.07.2002
Motion Tweening
- keyframe - in-between frames - keyframe
- Motion tweens: move objects around stage, change properties
- Shape tweens: morph shapes
- Motion tweens only work on symbols or groups
- Each object that's moving needs to be on its own layer
Applying a Motion Tween
- Place content on stage, either a symbol or a group
- Create an end keyframe and move the object where it should end up
- Select the frames between the keyframes
- On the Frame panel, select "Motion" tweening
A dotted arrow in the timeline means your tween is not working.
Scaling
Motion tweening can change size of objects.
Ensure that "Scale" checkbox is checked on Frame panel
Rotation
On Frame panel, Rotate dropdown has four options:
- None
- Auto
- CW (clockwise)
- CCW (counter-clockwise)
If you rotate your object at one keyframe, "Auto" rotates the simplest direction. CW forces clockwise rotation, CCW, counter-clockwise. To change the number of times the object rotates, put a number in the "times" box.
Changing the center of rotation
Modify > Transform > Edit Center
Easing
Easing controls acceleration and deceleration
- Easing in (negative value) starts slow, accelerates
- Easing out (positive value) starts fast, slows down
Onion Skinning
Onion skin buttons at bottom of timeline allow you to see multiple frames at once. The buttons are:
- Onion Skin
- Onion Skin Outlines
- Edit Multiple Frames
- Modify Onion Markers
- Always Show Markers
- Anchor Markers
- Onion 2
- Onion 5
- Onion All
Dragging the markers at top of timeline controls which frames are onion skinned
Editing Multiple Frames
Markers indicate which frames are being edited. This is ideal for fine-tuning complex animations and moving an entire animation at once.
Tweening Effects
Any of the effects from the Effects palette can be modified by motion tweens. Remember that effects can only be applied to symbols, not groups.
Motion Guides
Paths for objects to follow while moving through a motion tween.
- Make sure Snap to Objects is on
- With your tween layer selected, Insert > Motion Guide
- Draw a line for the object to follow. Make sure that the ends are reasonably close to the start and end point of the motion
- Drag the center/ registration point of the object and snap it to the motion guide at each keyframe
- Apply the motion tween
The tweened object's registration point must snap to the motion guide at each keyframe, otherwise it won't follow the path. The motion guide must exist through every frame that the tween runs.