XRServer

Inherits: Object

Server for AR and VR features.

Description

The AR/VR server is the heart of our Advanced and Virtual Reality solution and handles all the processing.

Tutorials

Properties

XRInterface

primary_interface

Transform3D

world_origin

Transform3D(1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0)

float

world_scale

1.0

Methods

void

add_interface ( XRInterface interface )

void

add_tracker ( XRPositionalTracker tracker )

void

center_on_hmd ( RotationMode rotation_mode, bool keep_height )

XRInterface

find_interface ( String name ) const

Transform3D

get_hmd_transform ( )

XRInterface

get_interface ( int idx ) const

int

get_interface_count ( ) const

Dictionary[]

get_interfaces ( ) const

Transform3D

get_reference_frame ( ) const

XRPositionalTracker

get_tracker ( StringName tracker_name ) const

Dictionary

get_trackers ( int tracker_types )

void

remove_interface ( XRInterface interface )

void

remove_tracker ( XRPositionalTracker tracker )

Signals

interface_added ( StringName interface_name )

Emitted when a new interface has been added.

interface_removed ( StringName interface_name )

Emitted when an interface is removed.

tracker_added ( StringName tracker_name, int type )

Emitted when a new tracker has been added. If you don't use a fixed number of controllers or if you're using XRAnchor3Ds for an AR solution, it is important to react to this signal to add the appropriate XRController3D or XRAnchor3D nodes related to this new tracker.

tracker_removed ( StringName tracker_name, int type )

Emitted when a tracker is removed. You should remove any XRController3D or XRAnchor3D points if applicable. This is not mandatory, the nodes simply become inactive and will be made active again when a new tracker becomes available (i.e. a new controller is switched on that takes the place of the previous one).

tracker_updated ( StringName tracker_name, int type )

Emitted when an existing tracker has been updated. This can happen if the user switches controllers.

Enumerations

enum TrackerType:

TrackerType TRACKER_HEAD = 1

The tracker tracks the location of the players head. This is usually a location centered between the players eyes. Note that for handheld AR devices this can be the current location of the device.

TrackerType TRACKER_CONTROLLER = 2

The tracker tracks the location of a controller.

TrackerType TRACKER_BASESTATION = 4

The tracker tracks the location of a base station.

TrackerType TRACKER_ANCHOR = 8

The tracker tracks the location and size of an AR anchor.

TrackerType TRACKER_ANY_KNOWN = 127

Used internally to filter trackers of any known type.

TrackerType TRACKER_UNKNOWN = 128

Used internally if we haven't set the tracker type yet.

TrackerType TRACKER_ANY = 255

Used internally to select all trackers.

enum RotationMode:

RotationMode RESET_FULL_ROTATION = 0

Fully reset the orientation of the HMD. Regardless of what direction the user is looking to in the real world. The user will look dead ahead in the virtual world.

RotationMode RESET_BUT_KEEP_TILT = 1

Resets the orientation but keeps the tilt of the device. So if we're looking down, we keep looking down but heading will be reset.

RotationMode DONT_RESET_ROTATION = 2

Does not reset the orientation of the HMD, only the position of the player gets centered.

Property Descriptions

XRInterface primary_interface

The primary XRInterface currently bound to the XRServer.

Transform3D world_origin = Transform3D(1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0)

The current origin of our tracking space in the virtual world. This is used by the renderer to properly position the camera with new tracking data.

Note: This property is managed by the current XROrigin3D node. It is exposed for access from GDExtensions.

float world_scale = 1.0

  • void set_world_scale ( float value )

  • float get_world_scale ( )

Allows you to adjust the scale to your game's units. Most AR/VR platforms assume a scale of 1 game world unit = 1 real world meter.

Method Descriptions

void add_interface ( XRInterface interface )

Registers an XRInterface object.

void add_tracker ( XRPositionalTracker tracker )

Registers a new XRPositionalTracker that tracks a spatial location in real space.

void center_on_hmd ( RotationMode rotation_mode, bool keep_height )

This is an important function to understand correctly. AR and VR platforms all handle positioning slightly differently.

For platforms that do not offer spatial tracking, our origin point (0, 0, 0) is the location of our HMD, but you have little control over the direction the player is facing in the real world.

For platforms that do offer spatial tracking, our origin point depends very much on the system. For OpenVR, our origin point is usually the center of the tracking space, on the ground. For other platforms, it's often the location of the tracking camera.

This method allows you to center your tracker on the location of the HMD. It will take the current location of the HMD and use that to adjust all your tracking data; in essence, realigning the real world to your player's current position in the game world.

For this method to produce usable results, tracking information must be available. This often takes a few frames after starting your game.

You should call this method after a few seconds have passed. For example, when the user requests a realignment of the display holding a designated button on a controller for a short period of time, or when implementing a teleport mechanism.

XRInterface find_interface ( String name ) const

Finds an interface by its name. For example, if your project uses capabilities of an AR/VR platform, you can find the interface for that platform by name and initialize it.

Transform3D get_hmd_transform ( )

Returns the primary interface's transformation.

XRInterface get_interface ( int idx ) const

Returns the interface registered at the given idx index in the list of interfaces.

int get_interface_count ( ) const

Returns the number of interfaces currently registered with the AR/VR server. If your project supports multiple AR/VR platforms, you can look through the available interface, and either present the user with a selection or simply try to initialize each interface and use the first one that returns true.

Dictionary[] get_interfaces ( ) const

Returns a list of available interfaces the ID and name of each interface.

Transform3D get_reference_frame ( ) const

Returns the reference frame transform. Mostly used internally and exposed for GDExtension build interfaces.

XRPositionalTracker get_tracker ( StringName tracker_name ) const

Returns the positional tracker with the given tracker_name.

Dictionary get_trackers ( int tracker_types )

Returns a dictionary of trackers for tracker_types.

void remove_interface ( XRInterface interface )

Removes this interface.

void remove_tracker ( XRPositionalTracker tracker )

Removes this positional tracker.