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Alignment of the controller coordinate system (defined in OpenVR): X-axis pointing left, Y pointing upwards along the handle and Z pointing perpendicular into the touchpadby SteamVR): the coordinate frame is centered in the body of the controller, under the touchpad. The Z axis points along the handle towards the user, the Y axis points perpendicularly up through the touchpad and the X axis points to the right. Note that in order to avoid cluttering this image only one marker post is attached but at least 3 markers are required for proper optical tracking.