javascript
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three.js
mirror of https://github.com/tazdij/three.js.git


			
				
					
						
						
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		[page:Object3D] &rarr; [page:Light] &rarr;

		<h1>[name]</h1>

		<p class="desc">
			A light that gets emitted from a single point in all directions. A common use case for this
			is to replicate the light emitted from a bare lightbulb.<br /><br />

			 This light can cast shadows - see [page:PointLightShadow] page for details.
		</p>

		<h2>Code Example</h2>

		<code>
const light = new THREE.PointLight( 0xff0000, 1, 100 );
light.position.set( 50, 50, 50 );
scene.add( light );
		</code>

		<h2>Examples</h2>

		<p>
			[example:webgl_lights_pointlights lights / pointlights ]<br />
			[example:webgl_effects_anaglyph effects / anaglyph ]<br />
			[example:webgl_geometry_text geometry / text ]<br />
			[example:webgl_lensflares lensflares ]
		</p>

		<h2>Constructor</h2>

		<h3>[name]( [param:Integer color], [param:Float intensity], [param:Number distance], [param:Float decay] )</h3>
		<p>
			[page:Integer color] - (optional) hexadecimal color of the light. Default is 0xffffff (white).<br />
			[page:Float intensity] - (optional) numeric value of the light's strength/intensity. Default is 1.<br /><br />
			[page:Number distance] - Maximum range of the light. Default is 0 (no limit).<br />
			[page:Float decay] - The amount the light dims along the distance of the light. Default is 1.
			For [page:WebGLRenderer.physicallyCorrectLights physically correct] lighting, set this to 2.<br /><br />

			Creates a new [name].
		</p>

		<h2>Properties</h2>
		<p>
			See the base [page:Light Light] class for common properties.
		</p>

		<h3>[property:Float decay]</h3>
		<p>
			The amount the light dims along the distance of the light<br />
			In [page:WebGLRenderer.physicallyCorrectLights physically correct] mode, decay = 2 leads to physically realistic light falloff.<br/>
			Default is *1*.
		</p>

		<h3>[property:Float distance]</h3>
		<p>
			<em>Default mode</em> — When distance is zero, light does not attenuate. When distance is
			non-zero, light will attenuate linearly from maximum intensity at the light's position down to
			zero at this distance from the light.
		</p>
		<p>
			<em>[page:WebGLRenderer.physicallyCorrectLights Physically correct] mode</em> — When distance
			is zero, light will attenuate according to inverse-square law to infinite distance. When
			distance is non-zero, light will attenuate according to inverse-square law until near the
			distance cutoff, where it will then attenuate quickly and smoothly to 0. Inherently, cutoffs
			are not physically correct.
		</p>
		<p>
			Default is *0.0*.
		</p>

		<h3>[property:Float power]</h3>
		<p>
			The light's power.<br />
			In [page:WebGLRenderer.physicallyCorrectLights physically correct] mode, the luminous
			power of the light measured in lumens. Default is *4Math.PI*. <br /><br />

			This is directly related to the [page:.intensity intensity] in the ratio
			<code>
				power = intensity * 4&pi;
			</code>
			and changing this will also change the intensity.
		</p>

		<h3>[property:PointLightShadow shadow]</h3>
		<p>
			A [page:PointLightShadow] used to calculate shadows for this light.<br /><br />

			 The lightShadow's [page:LightShadow.camera camera]
			is set to a  [page:PerspectiveCamera] with [page:PerspectiveCamera.fov fov] of 90,
			[page:PerspectiveCamera.aspect aspect] of 1, [page:PerspectiveCamera.near near]
			clipping plane at 0.5 and	[page:PerspectiveCamera.far far] clipping plane at 500.
		</p>

		<h2>Methods</h2>
		<p>
			See the base [page:Light Light] class for common methods.
		</p>

		<h3>[method:PointLight dispose]()</h3>
		<p>
		Override of base class's [page:Light.dispose dispose].
		Disposes of this light's [page:PointLightShadow shadow].
		</p>

		<h3>[method:PointLight copy]( [param:PointLight source] )</h3>
		<p>
		Copies value of all the properties from the [page:PointLight source] to this
		PointLight.
		</p>

		<h2>Source</h2>

		<p>
			[link:https://github.com/mrdoob/three.js/blob/master/src/[path].js src/[path].js]
		</p>
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