In order to control motion matching, Input-Response Data needs to be provided to the motion matching node. For the vast majority of cases this comes in the form of a Trajectory that can be generated either by user input or AI Navigation input. Typically, trajectories are generated by recording the past and predicting future trajectory points, up to a time horizon of 1 second. Each trajectory point contains data on relative location and facing direction of the character.

This data is converted into a simple float array and stored in an ‘InputData’ variable before being fed into the motion matching node in the animation graph. A ‘Trajectory Generator’ component is required for this data to be extracted. Please see the section on ‘Input Response Data’ for details on how to extract this data.

For most users the ‘Trajectory Generator Component’ will be sufficient to handle generation of trajectories at runtime. This is a component that sits on your character’s blueprint and can output a trajectory based on user input.