XrHitTestSource[]sources 

List of active XrHitTestSource.

booleansupported 

True if AR Hit Test is supported.

start([options]) 

Attempts to start hit test with provided reference space.

app.xr.hitTest.start({
    spaceType: pc.XRSPACE_VIEWER,
    callback: function (err, hitTestSource) {
        if (err) return;
        hitTestSource.on('result', function (position, rotation) {
            // position and rotation of hit test result
            // based on Ray facing forward from the Viewer reference space
        });
    }
});

const ray = new pc.Ray(new pc.Vec3(0, 0, 0), new pc.Vec3(0, -1, 0));
app.xr.hitTest.start({
    spaceType: pc.XRSPACE_LOCAL,
    offsetRay: ray,
    callback: function (err, hitTestSource) {
        // hit test source that will sample real world geometry straight down
        // from the position where AR session started
    }
});

app.xr.hitTest.start({
    profile: 'generic-touchscreen',
    callback: function (err, hitTestSource) {
        if (err) return;
        hitTestSource.on('result', function (position, rotation, inputSource) {
            // position and rotation of hit test result
            // that will be created from touch on mobile devices
        });
    }
});

Parameters

options	object	Optional object for passing arguments.
options.spaceType	string	Reference space type. Defaults to XRSPACE_VIEWER. Can be one of the following: XRSPACE_VIEWER: Viewer - hit test will be facing relative to viewers space. XRSPACE_LOCAL: Local - represents a tracking space with a native origin near the viewer at the time of creation. XRSPACE_LOCALFLOOR: Local Floor - represents a tracking space with a native origin at the floor in a safe position for the user to stand. The y axis equals 0 at floor level. Floor level value might be estimated by the underlying platform. XRSPACE_BOUNDEDFLOOR: Bounded Floor - represents a tracking space with its native origin at the floor, where the user is expected to move within a pre-established boundary. XRSPACE_UNBOUNDED: Unbounded - represents a tracking space where the user is expected to move freely around their environment, potentially long distances from their starting point.
options.profile	string	if hit test source meant to match input source instead of reference space, then name of profile of the XrInputSource should be provided.
options.entityTypes	string[]	Optional list of underlying entity types against which hit tests will be performed. Defaults to [ XRTRACKABLE_PLANE ]. Can be any combination of the following: XRTRACKABLE_POINT: Point - indicates that the hit test results will be computed based on the feature points detected by the underlying Augmented Reality system. XRTRACKABLE_PLANE: Plane - indicates that the hit test results will be computed based on the planes detected by the underlying Augmented Reality system. XRTRACKABLE_MESH: Mesh - indicates that the hit test results will be computed based on the meshes detected by the underlying Augmented Reality system.
options.offsetRay	Ray	Optional ray by which hit test ray can be offset.
options.callback	XrHitTestStartCallback	Optional callback function called once hit test source is created or failed.

add 

Fired when new XrHitTestSource is added to the list.

app.xr.hitTest.on('add', function (hitTestSource) {
    // new hit test source is added
});

Parameters

hitTestSource

XrHitTestSource

Hit test source that has been added.

error 

Fired when failed create hit test source.

Parameters

error

Error

Error object related to failure of creating hit test source.

remove 

Fired when XrHitTestSource is removed to the list.

app.xr.hitTest.on('remove', function (hitTestSource) {
    // hit test source is removed
});

Parameters

hitTestSource

XrHitTestSource

Hit test source that has been removed.

result 

Fired when hit test source receives new results. It provides transform information that tries to match real world picked geometry.

app.xr.hitTest.on('result', function (hitTestSource, position, rotation, inputSource) {
    target.setPosition(position);
    target.setRotation(rotation);
});

Parameters

hitTestSource	XrHitTestSource	Hit test source that produced the hit result.
position	Vec3	Position of hit test.
rotation	Quat	Rotation of hit test.
inputSource	XrInputSource, null	If is transient hit test source, then it will provide related input source.

fire(name, [arg1], [arg2], [arg3], [arg4], [arg5], [arg6], [arg7], [arg8]) 

Fire an event, all additional arguments are passed on to the event listener.

obj.fire('test', 'This is the message');

Parameters

name	string	Name of event to fire.
arg1	*	First argument that is passed to the event handler.
arg2	*	Second argument that is passed to the event handler.
arg3	*	Third argument that is passed to the event handler.
arg4	*	Fourth argument that is passed to the event handler.
arg5	*	Fifth argument that is passed to the event handler.
arg6	*	Sixth argument that is passed to the event handler.
arg7	*	Seventh argument that is passed to the event handler.
arg8	*	Eighth argument that is passed to the event handler.

Returns

EventHandler

Self for chaining.

hasEvent(name) 

Test if there are any handlers bound to an event name.

obj.on('test', function () { }); // bind an event to 'test'
obj.hasEvent('test'); // returns true
obj.hasEvent('hello'); // returns false

Parameters

name

string

The name of the event to test.

Returns

boolean

True if the object has handlers bound to the specified event name.

off([name], [callback], [scope]) 

Detach an event handler from an event. If callback is not provided then all callbacks are unbound from the event, if scope is not provided then all events with the callback will be unbound.

const handler = function () {
};
obj.on('test', handler);

obj.off(); // Removes all events
obj.off('test'); // Removes all events called 'test'
obj.off('test', handler); // Removes all handler functions, called 'test'
obj.off('test', handler, this); // Removes all handler functions, called 'test' with scope this

Parameters

name	string	Name of the event to unbind.
callback	HandleEventCallback	Function to be unbound.
scope	object	Scope that was used as the this when the event is fired.

Returns

EventHandler

Self for chaining.

on(name, callback, [scope]) 

Attach an event handler to an event.

obj.on('test', function (a, b) {
    console.log(a + b);
});
obj.fire('test', 1, 2); // prints 3 to the console

const evt = obj.on('test', function (a, b) {
    console.log(a + b);
});
// some time later
evt.off();

Parameters

name	string	Name of the event to bind the callback to.
callback	HandleEventCallback	Function that is called when event is fired. Note the callback is limited to 8 arguments.
scope	object	Object to use as 'this' when the event is fired, defaults to current this.

Returns

EventHandle

Can be used for removing event in the future.

once(name, callback, [scope]) 

Attach an event handler to an event. This handler will be removed after being fired once.

obj.once('test', function (a, b) {
    console.log(a + b);
});
obj.fire('test', 1, 2); // prints 3 to the console
obj.fire('test', 1, 2); // not going to get handled

Parameters

name	string	Name of the event to bind the callback to.
callback	HandleEventCallback	Function that is called when event is fired. Note the callback is limited to 8 arguments.
scope	object	Object to use as 'this' when the event is fired, defaults to current this.

Returns

EventHandle

• can be used for removing event in the future.