/**
A **PointLight** is a {{#crossLink "Light"}}{{/crossLink}} that defines a positional light source that originates from a single point and spreads outward in all directions.
## Overview
<ul>
<li>PointLights have a position, but no direction.</li>
<li>PointLights may be defined in either **World** or **View** coordinate space. When in World-space, their position
is relative to the World coordinate system, and will appear to move as the {{#crossLink "Camera"}}{{/crossLink}} moves.
When in View-space, their position is relative to the View coordinate system, and will behave as if fixed to the viewer's
head as the {{#crossLink "Camera"}}{{/crossLink}} moves.</li>
<li>PointLights have {{#crossLink "PointLight/constantAttenuation:property"}}{{/crossLink}}, {{#crossLink "PointLight/linearAttenuation:property"}}{{/crossLink}} and
{{#crossLink "PointLight/quadraticAttenuation:property"}}{{/crossLink}} factors, which indicate how their intensity attenuates over distance.</li>
</ul>
## Example
In the example below we're illuminating a {{#crossLink "TeapotObject"}}{{/crossLink}} with a single PointLight.
<iframe style="width: 600px; height: 400px" src="../../examples/light_PointLight.html"></iframe>
```` javascript
// Create a Viewer
var viewer = new BIMSURFER.Viewer({ element: "myDiv" });
// Create a Camera
var camera = new BIMSURFER.Camera(viewer, {
eye: [5, 5, -5]
});
// Create a camera orbit control
var control = new BIMSURFER.CameraControl(viewer, {
camera: camera
});
// Create a TeapotObject
var teapot = new BIMSURFER.TeapotObject(viewer);
// Create a PointLight
var pointLight = new BIMSURFER.PointLight(viewer, {
color: [0.9, 0.9, 0.9],
pos: [-10.0, 10.0, 10.0],
constantAttenuation: 0.0,
linearAttenuation: 0.0,
quadraticAttenuation: 0.0,
space: "view"
});
````
@class PointLight
@module BIMSURFER
@submodule lighting
@constructor
@extends Light
@param [viewer] {Viewer} Parent {{#crossLink "Viewer"}}Viewer{{/crossLink}}.
@param [cfg] {*} The PointLight configuration
@param [cfg.id] {String} Optional ID, unique among all components in the parent {{#crossLink "Viewer"}}Viewer{{/crossLink}}, generated automatically when omitted.
@param [cfg.meta] {String:Object} Optional map of user-defined metadata to attach to this PointLight.
@param [cfg.pos=[ 1.0, 1.0, 1.0 ]] {Array(Number)} Position, in either World or View space, depending on the value of the **space** parameter.
@param [cfg.color=[0.7, 0.7, 0.8 ]] {Array(Number)} Diffuse color of this PointLight.
@param [cfg.constantAttenuation=0] {Number} Constant attenuation factor.
@param [cfg.linearAttenuation=0] {Number} Linear attenuation factor.
@param [cfg.quadraticAttenuation=0] {Number} Quadratic attenuation factor.
@param [cfg.space="view"] {String} The coordinate system this PointLight is defined in - "view" or "space".
*/
(function () {
"use strict";
BIMSURFER.PointLight = BIMSURFER.Light.extend({
className: "BIMSURFER.PointLight",
_init: function (cfg) {
this._super(BIMSURFER._apply({
mode: "point" }, cfg));
this.pos = cfg.pos;
this.color = cfg.color;
this.constantAttenuation = cfg.constantAttenuation;
this.linearAttenuation = cfg.linearAttenuation;
this.quadraticAttenuation = cfg.quadraticAttenuation;
this.space = cfg.space;
},
_props: {
/**
The position of this PointLight.
This will be either World- or View-space, depending on the value of {{#crossLink "PointLight/space:property"}}{{/crossLink}}.
@property pos
@default [1.0, 1.0, 1.0]
@type Array(Number)
*/
pos: {
set: function (value) {
this._pos = value;
this._update({
pos: { x: value[0], y: value[1], z: value[2] }
});
},
get: function () {
return this._pos;
}
},
/**
The color of this PointLight.
@property color
@default [0.7, 0.7, 0.8]
@type Array(Number)
*/
color: {
set: function (value) {
this._color = value;
this._update({
color: { r: value[0], g: value[1], b: value[2] },
specularColor: { r: value[0], g: value[1], b: value[2] }
});
},
get: function () {
return this._color;
}
},
/**
The constant attenuation factor for this PointLight.
@property constantAttenuation
@default 0
@type Number
*/
constantAttenuation: {
set: function (value) {
this._update({
constantAttenuation: this._constantAttenuation = value
});
},
get: function () {
return this._constantAttenuation;
}
},
/**
The linear attenuation factor for this PointLight.
@property linearAttenuation
@default 0
@type Number
*/
linearAttenuation: {
set: function (value) {
this._update({
linearAttenuation: this._linearAttenuation = value
});
},
get: function () {
return this._linearAttenuation;
}
},
/**
The quadratic attenuation factor for this Pointlight.
@property quadraticAttenuation
@default 0
@type Number
*/
quadraticAttenuation: {
set: function (value) {
this._update({
quadraticAttenuation: this._quadraticAttenuation = value
});
},
get: function () {
return this._quadraticAttenuation;
}
},
/**
Indicates which coordinate space this PointLight is in.
Supported values are:
<ul>
<li>"view" - View space, aligned within the view volume as if fixed to the viewer's head</li>
<li>"world" - World space, fixed within the world, moving within the view volume with respect to camera</li>
</ul>
@property space
@default "view"
@type String
*/
space: {
set: function (value) {
this._update({
space: this._space = value
});
},
get: function () {
return this._space;
}
}
}
});
})();
