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Using Motion Paths
Have you ever played with model trains where you can lay down sections of track with curves, twists, and straight segments where you want them? That's the basic principle behind motion paths. You set up a track, and the object runs along that track as its animation effect.Perhaps you are thinking, "Cool, but when would I ever use that, really?" You might be surprised. For example, suppose you are showing a map on a slide, and you want to graphically illustrate the route being taken when traveling. You could create a little square, circle, or even a tiny piece of clip art of a car or airplane, and then set a custom motion path for it that would trace the route on the map along certain highways.PowerPoint comes with dozens of motion paths in every shape you can imagine, and you can also create your own (for example, for situations like the aforementioned map).
Applying a Preset Motion Path
Let's start with something easy: a preset motion path. To apply a motion path, choose it just like you would choose an entrance or exit effect:
Display the Custom Animation task pane.
Select the object, click Add Effect, point to Motion Paths, and then click one of the paths on the list (see Figure 13-16). You can also opt to click More Motion Paths or Draw Custom Path (which I'll explain later).
If you choose More Motion Paths, choose the path from the Add Motion Path dialog box (see Figure 13-17). Then, click OK.
Figure 13-16: Choose one of the common motion paths from the menu or choose More Motion Paths for a more complete set.
Figure 13-17: The Add Motion Path dialog box provides a large set of motion paths from which to choose.
The motion path appears on the slide, adjacent to the animated object. A green arrow shows where the object will begin, and a dotted line shows the path it will take (see Figure 13-18). To change the starting point for the path, drag the green arrow. The motion path in Figure 13-18 is a closed shape, which means that the starting and ending points are the same. The object will travel along the motion path and end up back where it started.
Figure 13-18: The motion path appears on the slide. The green arrow is the starting point and shows the direction of the flow.
If you have selected a motion path that is a line rather than a shape, it will have both a start and an end point. The start point is a green arrow, and the end point is a red arrow with a line at its point (see Figure 13-19).
Figure 13-19: Line motion paths have starting and ending points.
You can change to a different motion path by selecting the animation in the task pane and clicking the Change button on the task pane, the same as with changing any other type of custom animation.
Modifying a Preset Motion Path
Motion paths are editable objects, much like AutoShapes. You can click one to place round white selection handles around it, and then drag those selection handles to resize it, either proportionally or in one dimension only. You can also drag the green rotation handle to rotate a motion path (see Figure 13-20).
Figure 13-20: A motion path is an object on the slide that can be moved, resized, and/or rotated like any other object.
But wait-there's a lot more you can do to modify a motion path. For starters, you can reverse the direction by switching the starting and ending points. To do so, right-click the motion path and choose Reverse Direction.
On a closed shape like the one in Figure 13-20, you can disconnect the starting and ending points so you have a separate red end-point marker. To do so, right-click the motion path and choose Open Path.You can also reshape the motion path. Right-click the motion path and choose Edit Points to allow this; black squares appear on the path, and you can drag the black squares to change the shape of the path. And if you have opened the path (see the previous example), you can also drag the ending and starting points to further modify the shape (see Figure 13-21).
Figure 13-21: Right-click and choose Edit Points to make all the points that make up the path draggable.
Creating a Custom Motion Path From Scratch
You saw in the preceding section how to modify an existing motion path, but what about creating your own from scratch, like for the aforementioned map example? Easy enough. Follow these steps:
Display the Custom Animation task pane, and select the object to be animated.
Choose Add Effect⇨Motion Paths⇨Draw Custom Path, and then choose the type of path you want: Line, Curve, Freeform, or Scribble.
Drag to draw on the slide the path you want.
Here are some tips for creating your motion path:
For a line, where you begin will be the start point and where you end will be the end point. However, you can always reverse this later, if desired (by right-clicking and choosing Reverse Direction).
For a Curve, click at the beginning of the line, then move the mouse a little, and click again to anchor the next point. Keep going like that until you have completely defined the curve. Don't draw the entire curve before you click! You need to create interim anchor points along the way. Double-click when finished.
For a Freeform path, click for each anchor point you want; straight lines will appear between them. Double-click when finished.
For a Scribble, the pointer changes to a pencil. Draw on the slide with the mouse button held down the whole time. Single or double-click when finished, or just release the mouse button and pause for a second.
You can modify these motion paths just as you can with the path shapes supplied by PowerPoint.
Locking and Unlocking Motion Paths
Open the Path drop-down list on the Custom Animation task pane for your motion path, and you'll find Locked and Unlocked settings. The default is Unlocked. Locking it locks the path into place so that if you move the object to which the path is applied, the path will remain in its own spot. Unlocked allows the path to move along with the object.
