5.5

184Motion User Guide
2D and 3D group properties in Motion
2D groups and 3D groups behave in different ways. And in the Group Inspector, 2D groups
and 3D groups have different parameters.
The Group Inspector for 3D groups contains Flatten and Layer Order parameters. Selecting
the Flatten checkbox places layers and groups inside the 3D group into a two-dimensional
plane. Selecting the Layer Order checkbox composites layers and groups inside the 3D
group according to their position in the Layers list rather than by depth order (position in
the canvas along the Z axis). See Create 3D intersection in Motion.
The Group Inspector for 2D groups contains the Fixed Resolution parameter. Selecting
the Fixed Resolution checkbox lets you manually set the size of a group, using sliders. By
default, Fixed Resolution is disabled and the size of the group is determined by the layers
in that group. See Constrain group size in Motion.
2D group properties
• Nested layers and groups are composited in the canvas in layer order (hierarchical order
in the Layers list). However, adjacent 3D groups that are not nested in 2D groups can
intersect based on depth order.
In the example above, the two gray balls in the 2D “Foreground” group are composited
on top of the rest of the scene. “Orange A” and “Yellow B” intersect because they are
3D groups, but neither of them can intersect with the 2D root-level groups.
• A 2D group can be nested in a 3D group.
• A 2D group not nested in a 3D group is locked to the camera, even if the camera is
animated. (For more information about cameras, see Cameras and views in Motion.