Shape Tween

Shape tweening is an an effect similar to morphing, in which one shape appears to change into another shape over time. The following steps will walk you through the process of creating a shape tween.

Step 1

Open a new Flash file and draw a circle on the stage, or pull the Circle symbol from the Library. If you use the Circle from the Library, you will need to convert it from an instance of the Circle symbol to a separate shape graphic. To do this, highlight the circle and select Modify | Break Apart from the menu. The instance is now a shape.

Once you've done that, notice that the first frame of your timeline is now a filled keyframe.

Step 2

Select Frame 20 of the timeline.

Choose Insert | Keyframe from the menu. This copies the content of Keyframe1 to Keyframe 20. This is a good option if you want the final shape to be similar enough to the starting shape that modifying the starting shape is easier than drawing a completely new shape.

If you select Insert | Blank Keyframe, Flash will add a keyframe at frame 20 but it won't contain any graphics. This is a better option if you intend to tween two entirely different shapes.

Step 3

Making sure that Frame 20 is still selected, change the circle's shape or delete the circle and and draw a different shape. To maximize the tween effect, make the new shape as different as possible from the original circle in terms of size, color and location.

Click back and forth between the two keyframes to see the two shapes that you're going to tween.

Step 4

Now, click on the first keyframe again. In the Property Inspector, select Shape in the Tween drop-down menu.

Step 5

Press the Enter key on your keyboard, or select Control | Test Movie from the menu. You'll see the tween as it would actually appear in a finished movie.

Note that the test movie loops indefinitely - we will cover basic movie control in the next section.