Understanding default rendering order

The order in which After Effects renders the various parts of a composition can affect the look of some visual effects in a rendered movie. An understanding of how After Effects renders a composition will help you get the results you want.

In rendering a composition, After Effects processes 2D layers in the order in which they are listed in the Timeline window, starting at the bottom of the list. However, After Effects processes 3D layers in Z order within their 3D bins. (See 3D rendering.) In processing each layer, After Effects processes changes from the top down, as these three categories appear in the Timeline window: first the masks, then effects, and finally the transformations. The blending modes and track mattes are processed after that. For elements with multiple effects, After Effects processes these in the order in which they are listed in the Effect Controls and the Timeline windows.