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Holy Displacement Map!Displacing a superhero logo
|Our final animation we will create in this exercise.|
Before diving into the exercise, lets first discuss what Displacement Mapping is. This Production Bundle effect displaces a layer both horizontally and vertically based on a color or luminance channel of another layer. Depending on the amount of displacement, the image will shift in a positive or negative direction. Displacement Mapping will work with any image, but I found you get your best results when you are using a grayscale image (Black areas displace in a negative direction, white areas displace in a positive direction, while gray areas (50%) do not displace at all).
|Figure 1 Displacement Map Interface|
In the case of animating a displacement map (what we are doing in this exercise) a few things need to be taken into consideration. Animated displacement maps see the mapped layer at its source in other words it ignores masks, effects and keyframes. So how can we use an animated layer as a displacement map? Simple, precompose the layer. This takes all of the masks, effects, and keyframes and places them in a different composition so that when the precomposed layer is used as the displacement map, the effect is looking only at a source layer.
The other thing to keep in mind is you can get strange results if the layer being displaced (the source layer) has other effects, keyframes, or even is a different size than the composition or the Displacement Map layer. To solve this, again, it is a good idea to precompose the layer first.
With a better understanding of how displacement mapping works, lets go ahead and create our own Bat Signal animation.
Note: Even though this tutorial works in After Effects 5.0 and 5.5, Ill be using After Effects 6.0 for this exercise.
Related Keywords:displacement map, after effects, pro, effects, schleicher
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