XrLightEstimation
Extends: EventHandler
Light Estimation provides illumination data from the real world, which is estimated by the underlying AR system. It provides a reflection Cube Map, that represents the reflection estimation from the viewer position. A more simplified approximation of light is provided by L2 Spherical Harmonics data. And the most simple level of light estimation is the most prominent directional light, its rotation, intensity and color.
Summary
Properties
available | True if estimated light information is available. |
color | Color of what is estimated to be the most prominent directional light. |
intensity | Intensity of what is estimated to be the most prominent directional light. |
rotation | Rotation of what is estimated to be the most prominent directional light. |
supported | True if Light Estimation is supported. |
Methods
end | End estimation of illumination data. |
start | Start estimation of illumination data. |
Events
available | Fired when light estimation data becomes available. |
error | Fired when light estimation has failed to start. |
Inherited
Methods
fire | Fire an event, all additional arguments are passed on to the event listener. |
hasEvent | Test if there are any handlers bound to an event name. |
off | Detach an event handler from an event. |
on | Attach an event handler to an event. |
once | Attach an event handler to an event. |
Details
Properties
True if estimated light information is available.
if (app.xr.lightEstimation.available) {
entity.light.intensity = app.xr.lightEstimation.intensity;
}
Color of what is estimated to be the most prominent directional light. Or null if data is not available.
Intensity of what is estimated to be the most prominent directional light. Or null if data is not available.
Rotation of what is estimated to be the most prominent directional light. Or null if data is not available.
True if Light Estimation is supported. This information is available only during an active AR session.
Methods
end()
End estimation of illumination data.
start()
Start estimation of illumination data. Availability of such data will come later and an
available
event will be fired. If it failed to start estimation, an error
event will be
fired.
app.xr.on('start', function () {
if (app.xr.lightEstimation.supported) {
app.xr.lightEstimation.start();
}
});
Events
available
Fired when light estimation data becomes available.
error
Fired when light estimation has failed to start.
app.xr.lightEstimation.on('error', function (ex) {
// has failed to start
});
Parameters
error | Error | Error object related to failure of light estimation start. |
Inherited
Methods
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
EventHandlerSelf 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
booleanTrue 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
EventHandlerSelf 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
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
EventHandlerSelf for chaining.
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
EventHandlerSelf for chaining.