Input for OpenVR controllers

For the Unity Editor to support OpenVR tracked controllers, the Unity VR subsystem presents VR controller inputs as separate joysticks. Use the UnityEngine.Input class to access the axis and button values.

OpenVR’s Unity integration doesn’t refer to any specific hardware when presenting axis and button states. This page provides the axis and button mappings for the three types of controllers supported by OpenVR: HTC Vive, Oculus Touch, and Valve Knuckles Controllers.

Naming convention and detection

When properly configured and connected, any OpenVR-compatible controllers are internally named as either OpenVR Controller - Left or OpenVR Controller - Right. Access this name through the list returned by UnityEngine.Input.GetJoystickNames(). When available, these controllers appear highlighted in green in the SteamVR status menu when tested with Steam. To access this menu you must have both Steam and SteamVR installed and running on your machine.

You can test the availability of these controllers by periodically checking for their presence in the list of joystick names through script. When the controllers turn off, or when you remove their batteries, an empty string replaces their name in the list returned by UnityEngine.Input.GetJoystickNames(). When the controllers turn on again, their name reappears in the list of returned joysticks.

Unity input system mappings

This section provides diagrams for each type of controller supported by OpenVR devices, along with information on the internal Unity input mapping for each controller button.

HTC Vive controllers

The diagram below displays the different inputs available on HTC Vive controllers for use in VR applications.

1	Menu Button
2	Trackpad
3	System button
4	Status light
5	Micro-USB port
6	Tracking sensor
7	Trigger
8	Grip button

Oculus Touch controllers

The diagram below displays the different inputs available on Oculus Touch controllers for use in VR applications.

Knuckles controllers

The diagram below displays the different inputs available when using Knuckles controllers in VR applications.

The table below lists controller inputs for each OpenVR-supported controller, their interaction types, Unity axis and button IDs, along with the value range for each axis.

HTC Vive Controller	Oculus Touch Controller	Valve Knuckles Controller	Interaction Type	Unity Button ID	Unity Axis ID	Unity Axis Value Range
Left Controller Menu Button (1)	Button.Three	Left Controller Inner Face Button	Press	2
Right Controller Menu Button (1)	Button.One	Right Controller Inner Face Button	Press	0
		Left Controller Outer Face Button	Press	3
		Right Controller Outer Face Button	Press	1
Left Controller Trackpad (2)	Button.PrimaryThumbstick	Left Controller Trackpad	Press	8
Right Controller Trackpad (2)	Button.SecondaryThumbstick	Right Controller Trackpad	Press	9
Left Controller Trackpad (2)	Button.PrimaryThumbstick	Left Controller Trackpad	Touch	16
Right Controller Trackpad (2)	Button.SecondaryThumbstick	Right Controller Trackpad	Touch	17
Left Controller Trackpad (2)	Axis2D.PrimaryThumbstick	Left Controller Trackpad	Horizontal Movement		1	–1.0 to 1.0
Left Controller Trackpad (2)	Axis2D.PrimaryThumbstick	Left Controller Trackpad	Vertical Movement		2	–1.0 to 1.0
Right Controller Trackpad (2)	Axis2D.SecondaryThumbstick	Right Controller Trackpad	Horizontal Movement		4	–1.0 to 1.0
Right Controller Trackpad (2)	Axis2D.SecondaryThumbstick	Right Controller Trackpad	Vertical Movement		5	–1.0 to 1.0
Left Controller Trigger (7)	Axis1D.PrimaryIndexTrigger	Left Controller Trigger	Touch	14
Right Controller Trigger (7)	Axis1D.SecondaryIndexTrigger	Right Controller Trigger	Touch	15
Left Controller Trigger (7)	Axis1D.PrimaryIndexTrigger	Left Controller Trigger	Squeeze		9	0.0 to 1.0
Right Controller Trigger (7)	Axis1D.SecondaryIndexTrigger	Right Controller Trigger	Squeeze		10	0.0 to 1.0
Left Controller Grip Button (8)	Axis1D.PrimaryHandTrigger	Left Controller Grip Average	Squeeze		11	0.0 to 1.0
Right Controller Grip Button (8)	Axis1D.SecondaryHandTrigger	Right Controller Grip Average	Squeeze		12	0.0 to 1.0
		Left Controller Index Finger Cap Sensor			20	0.0 to 1.0
		Right Controller Index Finger Cap Sensor			21	0.0 to 1.0
		Left Controller Middle Finger Cap Sensor			22	0.0 to 1.0
		Right Controller Middle Finger Cap Sensor			23	0.0 to 1.0
		Left Controller Ring Finger Cap Sensor			24	0.0 to 1.0
		Right Controller Ring Finger Cap Sensor			25	0.0 to 1.0
		Left Controller Pinky Finger Cap Sensor			26	0.0 to 1.0
		Right Controller Pinky Finger Cap Sensor			27	0.0 to 1.0

Note: Any hardware features not listed in the table above are not exposed through the OpenVR API and are therefore not exposed through Unity’s input system.

Important controller differences

When developing applications to support OpenVR devices, it is important to note certain differences in input event triggers and response rates for buttons on all three controllers.

Unity Touch Input events differ for each platform controller:

• The Event System generates Input Touch events for the triggers on HTC Vive controllers when the user begins squeezing the trigger.
• The Event System generates Input Touch events for the triggers on Oculus Touch and Valve Knuckles controllers when Unity Input detects a touch - no trigger squeeze is necessary.

The grip trigger differs between platforms:

• The HTC Vive controllers each have two grip buttons but both map to the same axis. The value for these buttons is 0.0 when not pressed and 1.0 when pressed (intermediate values between 0.0 and 1.0 are not possible).

• The grip on the Oculus Touch Controller is an analog trigger with a range from 0.0 to 1.0 (intermediate values are possible).

• The grip on the Valve Knuckles Controller is a weighted average of the input values for each of the individual finger touch sensors.