Mapping the Earth as a 3D Effect
Any vector graphic can be mapped onto a 3D Revolve effect. The only requirement is that the vector artwork must be saved as a symbol. I'll show you how to do that shortly. In this example, we're going to map a map, which poses a challenge—finding a map that fits on a globe.
It's oddly hard to find great mappable Illustrator global maps. The U.S. government and others make available high-quality maps of the planet, but of course they're bitmaps, not Illustrator-friendly vector maps. Why not just work with a bitmapped map in Illustrator? Because even 300 dpi maps look grainy when mapped onto a 3D effect.
To produce a nicely mapped map, you need a vector file—and not just any vector world map. To wrap a vector image of a map on your 3D sphere, you need a special kind of map—a Platte-Carrée projection map.
Platte-Carrée map layout takes the latitude and longitude grids of our spherical planet and distorts them onto a rectangle. Platte-Carrée maps look strangely distorted when laid out "flat." Greenland and other land masses near the poles are stretched way out in length. But when you map a Platte-Carrée projection back onto a sphere, it loses the distortion and "fits."
You can easily find a bitmap Platte-Carrée world map on the Web, but a vectorized format saves you the hassle of generating a vector file from a bitmap. Vectorized maps cost money, so this project will have a version for folks who have resources to get a vectorized world map, and a low-budget version for those of us who need to save money by creating our own map from a traced bitmap.
Map Resources has hundreds of downloadable, royalty-free maps in Illustrator format. Each map file has many layers, so you can elect to display customized combinations of geographic features (mountains, rivers), political features (national borders), cities, towns, and so on. The selection at Map Resources includes several Platte-Carrée maps.
You can find Platte-Carrée raster maps all over the Internet, some of them easily traceable. Look for ones without a lot of detail. NASA photos of the earth are available in Platte-Carrée layout, and they'll work fine for this project.
Those of you with unlimited budgets for this tutorial should spring for a vector, Platte-Carrée map, as should anyone who is planning to do professional illustrations involving 3D map projections.
For those of us for whom $29.99 is out of our price range, we'll use one of the many Platte-Carrée maps available when you search Google Images for Platte-Carrée. Copy and paste one of those bitmap Platte-Carrée maps into Illustrator. Then, with the map selected, choose one of the preset Live Trace options from the Live Trace pop-up. I used Color 16 to trace a bitmap I found at Google Images (see Figure 6).
Figure 6 Tracing a downloaded bitmap Platte-Carrée map in Illustrator CS4.
With the map traced, drag the newly traced map into the Symbol panel to make it available for mapping. (If the Symbol panel isn't visible, choose Window > Symbol.) Give your new map a name, something like Platte-Carrée Projection Earth (see Figure 7).
Figure 7 Converting the vectorized Platte-Carrée map into a symbol.
You can delete the map itself; the version you need is in the Symbols panel and will be saved with the file.
Now comes the exciting part—mapping the Platte-Carrée projection onto the revolved globe. Once you do that, you can tilt the globe back and forth, or rotate it to any degree, and still see a proportional map. To complete the project, follow these steps:
- Select the revolved semicircle you created earlier, and open the Appearance panel (Window > Appearance).
- Click the 3D Revolve effect link in the Appearance panel to open the 3D Revolve Options dialog.
- Set rotation to 360° for a complete rotation.
- From the Surface drop-down menu, choose No Shading.
- Click the Map Art button in the 3D Revolve options dialog to open the Map Art dialog box. The mappable surface is displayed.
- From the Symbol drop-down list, choose your map.
- Click the Scale to Fit button to stretch your map to fit the globe.
the Preview checkbox in the Map Art dialog. Your system resources will get a
good workout, but eventually you'll see a preview of the mapped artwork on your
artboard (see Figure 8).
Figure 8 Previewing mapped artwork.
With the artwork mapped onto the 3D effect, click OK to close the Map Art dialog. Now you can use the 3D rotation tools in the 3D Revolve Options dialog (see Figure 9) to tilt or spin planet Earth, revealing any section of the globe.
Figure 9 3D Revolve options.