Last year, we updated our After Effects Apprentice video courses. As part of adding and reorganizing material, some movies got cut. But we hate to see anything go to waste, so we’re going to repost them here for free.
After Effects follows a very specific order of calculations when it renders each layer of each frame in a composition. The trick is, that order changes depending on circumstances, such as whether their source layer is made out of pixels (such as photographs and video), vector outlines (such as text and shape layers), or is switched between the two (such as Illustrator artwork, which can be treated as pixels or as vectors). What may seem like “random” behavior is actually very repeatable and thought out; you just have to know it.
- transforms (such as rotation and scale)
For vector-based layers, the order is:
Let’s say you have a layer with a Drop Shadow effect applied. And let’s also say that layer has its Scale and Rotation animated. If it’s a pixel-based layer, the shadow will be cast, and then scaled – which means the shadow will grow in size with the layer (good). However, rotation also follows the shadow, meaning the shadow direction will be rotated as well (bad).
This movie demonstrates issues like these, plus gives you an oft-overlooked option to work around render order based issues: the Transform effect. The course this movie came out of – After Effects Apprentice 08: Nesting and Precomposing – also shows how you can use multiple nested compositions to overcome other render order issues, as well as work more efficiently.
The reason this movie came out of the course is because it was replaced with an entire chapter devoted to render order exceptions – including new movies on continuous rasterization, collapse transformation, and the additional special cases that come with compound effects, in addition to a movie dedicated to just the Transform effect. If you don’t already have a lynda.com subscription, click here to get your first seven days free on us.
And now, onto the movie: