The basic objects that you manipulate in After Effects are flat, two-dimensional (2D) layers. When you make a layer a 3D layer, the layer itself remains flat, but it gains additional properties: Position (z), Anchor Point (z), Scale (z), Orientation, X Rotation, Y Rotation, Z Rotation, and Material Options properties. Material Options properties specify how the layer interacts with light and shadows. Only 3D layers interact with shadows, lights, and cameras.

2D layers (left) and layers with 3D properties (right)

Any layer can be a 3D layer, except an audio-only layer. Individual characters within text layers can optionally be 3D sublayers, each with their own 3D properties. A text layer with Enable Per-character 3D selected behaves just like a precomposition that consists of a 3D layer for each character. All camera and light layers have 3D properties.

By default, layers are at a depth (z-axis position) of 0. In After Effects, the origin of the coordinate system is at the upper-left corner; x (width) increases from left to right, y (height) increases from top to bottom, and z (depth) increases from near to far. Some video and 3D applications use a coordinate system that is rotated 180 degrees around the x axis; in these systems, y increases from bottom to top, and z increases from far to near.

You can transform 3D layers relative to the composition’s coordinate space, the layer’s coordinate space, or a custom space by selecting an axis mode.

You can add effects and masks to 3D layers, composite 3D layers with 2D layers, and create and animate camera and light layers to view or illuminate 3D layers from any angle.

All effects are 2D, including effects that simulate 3D distortions. This means that, for example, viewing a layer with the Bulge effect from the side will not show a protrusion.

As with all masks, mask coordinates on a 3D layer are in the 2D coordinate space of the layer.

Paul Tuersley provides a pair of scripts for converting a composition based on a layered Photoshop file into a set of 3D layers, www.adobe.com/go/learn_ae_paulphotoshop3dlayers.

You can download an example project from the AE Enhancers forum that shows how to arrange several 3D layers in the shape of a sphere, control the layers with a null layer, and light them: www.adobe.com/go/learn_ae_oscarussphere3d.

Several plug-ins add the ability to manipulate, warp, and extrude 3D shapes in After Effects. Rich Young of AE Portal provides information about Zaxwerks 3D Warps and Zaxwerks Invigorator PRO, two such products: www.adobe.com/go/learn_ae_richzaxwerks3d.