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- <html lang="en">
- <head>
- <meta charset="utf-8" />
- <base href="../../../" />
- <script src="page.js"></script>
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- </head>
- <body>
- [page:Object3D] → [page:Light] →
- <h1>[name]</h1>
- <p class="desc">
- A light that gets emitted in a specific direction. This light will behave
- as though it is infinitely far away and the rays produced from it are all
- parallel. The common use case for this is to simulate daylight; the sun is
- far enough away that its position can be considered to be infinite, and
- all light rays coming from it are parallel.<br /><br />
- This light can cast shadows - see the [page:DirectionalLightShadow] page
- for details.
- </p>
- <h2>A Note about Position, Target and rotation</h2>
- <p>
- A common point of confusion for directional lights is that setting the
- rotation has no effect. This is because three.js's DirectionalLight is the
- equivalent to what is often called a 'Target Direct Light' in other
- applications.<br /><br />
- This means that its direction is calculated as pointing from the light's
- [page:Object3D.position position] to the [page:.target target]'s position
- (as opposed to a 'Free Direct Light' that just has a rotation
- component).<br /><br />
- The reason for this is to allow the light to cast shadows - the
- [page:.shadow shadow] camera needs a position to calculate shadows
- from.<br /><br />
- See the [page:.target target] property below for details on updating the
- target.
- </p>
- <h2>Code Example</h2>
- <code>
- // White directional light at half intensity shining from the top.
- const directionalLight = new THREE.DirectionalLight( 0xffffff, 0.5 );
- scene.add( directionalLight );
- </code>
- <h2>Examples</h2>
- <p>
- [example:misc_controls_fly controls / fly ]<br />
- [example:webgl_effects_parallaxbarrier effects / parallaxbarrier ]<br />
- [example:webgl_effects_stereo effects / stereo ]<br />
- [example:webgl_geometry_extrude_splines geometry / extrude / splines ]<br />
- [example:webgl_materials_bumpmap materials / bumpmap ]
- </p>
- <h2>Constructor</h2>
- <h3>[name]( [param:Integer color], [param:Float intensity] )</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 />
- Creates a new [name].
- </p>
- <h2>Properties</h2>
- <p>See the base [page:Light Light] class for common properties.</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:DirectionalLightShadow] for details. The default is `false`.
- </p>
- <h3>[property:Boolean isDirectionalLight]</h3>
- <p>Read-only flag to check if a given object is of type [name].</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:DirectionalLightShadow shadow]</h3>
- <p>
- A [page:DirectionalLightShadow] used to calculate shadows for this light.
- </p>
- <h3>[property:Object3D target]</h3>
- <p>
- The DirectionalLight 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
- </p>
- <code>
- scene.add( light.target );
- </code>
- <p>
- 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:
- </p>
- <code>
- const targetObject = new THREE.Object3D();
- scene.add(targetObject);
-
- light.target = targetObject;
- </code>
- <p>The directionalLight will now track the target object.</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:DirectionalLight source] )</h3>
- <p>
- Copies value of all the properties from the [page:DirectionalLight source]
- to this DirectionalLight.
- </p>
- <h2>Source</h2>
- <p>
- [link:https://github.com/mrdoob/three.js/blob/master/src/[path].js src/[path].js]
- </p>
- </body>
- </html>
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