23
Enhancing the Illusion with Maps
Many of the more powerful effects in After Effects have properties that can be controlled with other layers. Some effects, such as Displacement Map, absolutely require these controller layers in order to work correctly. These layers that are used as controllers are often referred to as maps. Once you’re familiar with an effect, mastering maps is what you need to take them to the next level. In this chapter, we’re going to look at a few options that might help you when controlling effect properties with maps.
Making Maps in After Effects
Frequently, maps are made right here in After Effects. And it makes sense, as there some great tools for the job. There are gradient creators like 4-Color Gradient, Ramp, and the Gradient Overlay layer style. There are grayscale pattern generators like Fractal Noise and Cell Pattern. There is also a very powerful painting engine, which shares many features with the painting features in Adobe Photoshop.
Precomposing Maps
When making maps in After Effects, it is often (though not always) necessary to precompose the layers that the effects or painting are on. If this is not done, effects will often ignore the map layer’s effects, painting, and layer styles and instead look at the layer’s source content. This is because of the order in which objects are rendered. To “bake” the effects, layer styles, and painting into a layer, precompose it by selecting the layer, and going to the Layer menu and selecting Pre-compose (at the bottom). You can also use the handy shortcut Ctrl+Shift+C (Win)/Cmd+Shift+C (Mac). You’ll also want to make sure to choose the second option (Move all attributes into the new composition) in the Pre-compose dialog box. Note that you can also “bake” After Effects elements in a layer to use its effects as a map by rendering and reimporting it.
Figure 23.1
The Pre-compose dialog box.
Once precomposed, the results of effects (like Fractal Noise) can be used as maps by other effects (such as Displacement Map). In Figure 23.2, I’ve created a solid layer with Fractal Noise applied with the default settings, and then precomposed it. I then applied Displacement Map to the precomposed Fractal Noise. By default, the Displacement Map effect uses the layer
Figure 23.2
Precomposing the Fractal Noise effect allows us to use it as a displacement map layer in the Displacement Map effect. Kinda looks like mountainous terrain.
it is applied to as the Displacement Map Layer. I changed both the Use For Horizontal Displacement and Use For Vertical Displacement drop down menus to Luminance, and changed both the Max Horizontal Displacement and Max Vertical Displacement values to 5.
Making Maps Externally
While making maps in After Effects is the quickest way to go, it doesn’t always allow for the most possible control in map creation. For detailed maps (such as those created for photorealistic character displacement with the Displacement Map effect), I usually use an external program, such as Adobe Photoshop. Obviously, you can’t go wrong using Photoshop with After Effects. These two applications are brothers from another mother. However, there are a few additional issues (and tips) we need to be aware of when traversing this path.
Layer Size and Map Size
Many effects that use maps have built-in contingency plans for how to handle maps that are a different size than the layer. These settings typically allow you to center the map, tile it, or something along those lines. However, if you’re using maps to create a specific and detailed result, then these might produce undesirable results. This is usually the case with maps—such as shatter or displacement maps—that often have to line up perfectly with the layer with the effect applied to it.
For this reason, I almost always import such Photoshop documents as a Composition, not as Composition—Cropped Layers. This guarantees that the size of the layer to be affected, and the size of the map layer are imported at the exact same size. I find that this is the best way to achieve consistent results with maps that must line up perfectly with the layers they will adjust.
I realize that the Center option in effects that use maps will align the centers of both layers. But if the edges of one of the layers is off just a little, then the effect might treat them as different sizes, which can throw off your final results.
Editing Maps Created Externally
If you have a map created in Photoshop that you need to edit, a shortcut has been created for you in After Effects. First, select the footage in the Project panel. It must be the actual footage itself, NOT a composition or a folder containing the footage. Then, select Edit>Edit Original from the top of the interface, or use the keyboard shortcut Ctrl+E (Win)/Cmd+E (Mac). This will launch Photoshop (if it’s not already open), and it will open the selected document in Photoshop for editing.
Actually, this will not necessarily launch Photoshop per se, but it will launch whatever program your operating system has associated with Photoshop files. If you have Adobe Bridge (or the Mac’s Preview application, or the QuickTime Player, etc.) associated with PSD files, then that’s what gets launched. Change your operating system preferences for PSD files if you want After Effects’ Edit Original command to open Photoshop.
Reloading Maps Edited Externally
Instead of launching Photoshop from After Effects, you may make adjustments in Photoshop without using the Edit Original command. In that case, you may be frustrated to find that your changes in Photoshop are not reflected in After Effects. Don’t worry about this. Seriously. You don’t need to reimport your footage and start your work on that file over from scratch.
After Effects has a built-in feature to access the current version of an imported file, and use that version instead of the one that After Effects is using. This also works for any type of imported footage, not just Photoshop documents. To reload a piece of footage, you must first find the original footage in the Project panel. As with the Edit Original command, you must find the actual footage, and not a composition or folder. Once you’ve found it, right click on it and choose Reload Footage. This will force After Effects to access the file again, and update the file with any changes that have been made to it.