Reference Cinema 4D Cinema 4D Visualize, Broadcast, Studio Motion Tracker Motion Tracker Tags
Function available in CINEMA 4D Studio

Planar Constraint

Basic Planar

Planar Constraint

Tip:
This tag works only after 3D features have been created, i.e., a 3D reconstruction has taken place.

Using this tag, 3 or more Tracks/features can be selected that can be used to define a plane (e.g., the floor or, for an Object Tracker, a layer to be replaced) within the vertex cluster. Since this plane will most often correspond to a layer in the world coordinate system you can also define the world axis to which the plane should lie perpendicularly.

The tag can be used as follows for calibration (3 methods):