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- <!DOCTYPE html>
- <html lang="en">
- <head>
- <meta charset="utf-8" />
- <base href="../../../" />
- <script src="page.js"></script>
- <link type="text/css" rel="stylesheet" href="page.css" />
- </head>
- <body>
- [page:Object3D] → [page:Light] →
- <h1>[name]</h1>
- <p class="desc">
- This light gets emitted from a single point in one direction, along a cone
- that increases in size the further from the light it gets. <br /><br />
- This light can cast shadows - see the [page:SpotLightShadow] page for
- details.
- </p>
- <h2>Code Example</h2>
- <code>
- // white spotlight shining from the side, modulated by a texture, casting a shadow
- const spotLight = new THREE.SpotLight( 0xffffff );
- spotLight.position.set( 100, 1000, 100 );
- spotLight.map = new THREE.TextureLoader().load( url );
- spotLight.castShadow = true;
- spotLight.shadow.mapSize.width = 1024;
- spotLight.shadow.mapSize.height = 1024;
- spotLight.shadow.camera.near = 500;
- spotLight.shadow.camera.far = 4000;
- spotLight.shadow.camera.fov = 30;
- scene.add( spotLight );
- </code>
- <h2>Examples</h2>
- <p>
- [example:webgl_lights_spotlight lights / spotlight ]<br />
- [example:webgl_lights_spotlights lights / spotlights ]
- </p>
- <h2>Constructor</h2>
- <h3>
- [name]( [param:Integer color], [param:Float intensity], [param:Float distance], [param:Radians angle], [param:Float penumbra], [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 />
- [page:Float distance] - Maximum range of the light. Default is `0` (no
- limit).<br />
- [page:Radians angle] - Maximum angle of light dispersion from its
- direction whose upper bound is Math.PI/2.<br />
- [page:Float penumbra] - Percent of the spotlight cone that is attenuated
- due to penumbra. Takes values between zero and `1`. Default is zero.<br />
- [page:Float decay] - The amount the light dims along the distance of the
- light.<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 angle]</h3>
- <p>
- Maximum extent of the spotlight, in radians, from its direction. Should be
- no more than `Math.PI/2`. The default is `Math.PI/3`.
- </p>
- <h3>[property:Boolean castShadow]</h3>
- <p>
- If set to `true` light will cast dynamic shadows. *Warning*: This is
- expensive and requires tweaking to get shadows looking right. See the
- [page:SpotLightShadow] for details. The default is `false`.
- </p>
- <h3>[property:Float decay]</h3>
- <p>
- The amount the light dims along the distance of the light. Default is
- `2`.<br />
- In context of physically-correct rendering the default value should not be
- changed.
- </p>
- <h3>[property:Float distance]</h3>
- <p>
- 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 intensity]</h3>
- <p>
- The light's luminous intensity measured in candela (cd). Default is `1`.
- <br /><br />
- Changing the intensity will also change the light's power.
- </p>
- <h3>[property:Boolean isSpotLight]</h3>
- <p>Read-only flag to check if a given object is of type [name].</p>
- <h3>[property:Float penumbra]</h3>
- <p>
- Percent of the spotlight cone that is attenuated due to penumbra. Takes
- values between zero and `1`. The default is `0.0`.
- </p>
- <h3>[property:Vector3 position]</h3>
- <p>
- This is set equal to [page:Object3D.DEFAULT_UP] (0, 1, 0), so that the
- light shines from the top down.
- </p>
- <h3>[property:Float power]</h3>
- <p>
- The light's power.<br />
- Power is the luminous power of the light measured in lumens (lm).
- <br /><br />
- Changing the power will also change the light's intensity.
- </p>
- <h3>[property:SpotLightShadow shadow]</h3>
- <p>A [page:SpotLightShadow] used to calculate shadows for this light.</p>
- <h3>[property:Object3D target]</h3>
- <p>
- The Spotlight points from its [page:.position position] to
- target.position. The default position of the target is `(0, 0, 0)`.<br />
- *Note*: For the target's position to be changed to anything other than the
- default, it must be added to the [page:Scene scene] using
- <code> scene.add( light.target ); </code>
- This is so that the target's [page:Object3D.matrixWorld matrixWorld] gets
- automatically updated each frame.<br /><br />
- It is also possible to set the target to be another object in the scene
- (anything with a [page:Object3D.position position] property), like so:
- <code>
- const targetObject = new THREE.Object3D();
- scene.add(targetObject);
- light.target = targetObject;
- </code>
- The spotlight will now track the target object.
- </p>
- <h3>[property:Texture map]</h3>
- <p>
- A [page:Texture] used to modulate the color of the light. The spot light
- color is mixed with the RGB value of this texture, with a ratio
- corresponding to its alpha value. The cookie-like masking effect is
- reproduced using pixel values (0, 0, 0, 1-cookie_value). *Warning*:
- [page:.map] is disabled if [page:.castShadow] is *false*.
- </p>
- <h2>Methods</h2>
- <p>See the base [page:Light Light] class for common methods.</p>
- <h3>[method:undefined dispose]()</h3>
- <p>
- Frees the GPU-related resources allocated by this instance. Call this
- method whenever this instance is no longer used in your app.
- </p>
- <h3>[method:this copy]( [param:SpotLight source] )</h3>
- <p>
- Copies value of all the properties from the [page:SpotLight source] to
- this SpotLight.
- </p>
- <p>
- [link:https://github.com/mrdoob/three.js/blob/master/src/[path].js src/[path].js]
- </p>
- </body>
- </html>
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