How to Use Adobe After Effects & Photoshop to Create the Line-Map Animation Effect

Your travel video is almost complete, but needs that last element to show off your adventures. No Indiana Jones movie would be complete until you have fun creating an animated airplane-crossing-the-world map.

So, you've decided to come to one of the popular video workshops at our offices in Northern California. You live in Santa Barbara and plan to do some sightseeing on your trip back in the beautiful and desolate San Joaquin Valley. There's no better way to highlight the video of your return road trip than by creating a classic animated line careening along every curve of your circuitous route.

There are, of course, degrees of finesse you can accomplish with this effect if you have the time, the tools and the skill (or at least the interest to learn). If you're short on time, the quickest way to produce this effect is to simply find an image of a map encompassing your route, use a paint program to draw a line on one copy, load it and a clean copy into your favorite editing package and do a wipe between the two. Done.

If you have a little more time and are familiar with Photoshop and After Effects, you can, without much effort, create a very accurate line charging down every byway you took, complete with panning and zooming camera movements. If you're ready, here's how you do it.

Step 1

Find a map for your background. Use one that is larger than your required output, so you can zoom and pan over the map as well as your travel line without losing image quality. Our map of California is 1497×1535 pixels.

Step 2

Load your map into Photoshop and rename this map something like Map_with_Line.

Step 3

Create a new layer and name it Line

Step 4

With the pen tool, trace the route you want highlighted.

Step 5

Set the color of your line by choosing the foreground color, and use the Stroke Path with Brush tool to highlight your route to your liking. Be sure that you have the Line layer highlighted when you use the Stroke Path, to keep it separated from your base image. If your line is too narrow, wide or soft, you can change the stroke attributes in the Brush Options window. Save your new map as a layered PSD document.

Step 6

Open After Effects and create a new composition (comp) that is a little longer than your anticipated animation, using a preset for your output. Our comp length will be 20 seconds based on the NTSC DV preset.

Step 7

Import your layered Map_With_Line.PSD file as a comp and, when prompted, select Editable Layer Styles.

Step 8

Drag the Map_with_Line Layers folder into the composition timeline, making sure the Line layer is on top, and double-click on the Line layer. You may need to click on the Fit Up to 100% option to view the entire image.

Step 9

Select the Pen tool and, while working in the Layer window, draw a line that closely overlays your route. This will create a path that will be used as an animated mask by the Write-On effect.

Step 10

The location of the Write-On varies, depending on your version, so find it by doing a quick search in the Effects & Presets field.

Step 11

Step 12

Step 13

Copy and paste this layer into the Brush Position layer within the Write-On effect.

Step 14

You should now see a series of key frames that correspond to the pen path you just drew.

Step 15

Set your brush size larger than your route line. For an animated reveal that closely follows the bends in your route, make it just a tad larger. If your Pen path is less precise, you may have to use a larger brush size. We used a setting of 20.

Step 16

Change the Paint Style to Reveal Original Image. This is located at the bottom of the Write-On options.

Step 17

Depending on how much larger your map is than the NTSC preset, you may see only a portion of your image. Don't worry, we'll see it all in a moment. Now hit the RAM preview button to view what you have so far.

Step 18

It is likely you will want to change the speed of your animated line. To do this, first highlight all of your key frames, then go into the graph edit mode and drag the group to the right to slow down your line or to the left to speed things up. We quickly lengthened the timing of our line from two to nine seconds with this method.

Step 19

Now for more fun, parent the line layer to the Map layer and, with the base layer now selected, let's zoom into and pan (scale and position) the map to where the line begins and create a key frame.

Step 20

Drag the timeline cursor to the end of the animated line, pan the map to that point and create another key frame.

Step 21

Analyze your movement and add additional key frames as necessary to track the tip of your travelling route as it meanders down the state.

Step 22

To smooth out the movement further, adjust the Brush Position key frames left or right.

You now should have a simple animated line that closely follows your defined path. If you want to push this effect even further, look into modifying this base animation with the 3D effects that come packaged with After Effects.