L


light
Computer displays use additive light. Additive light is created by combining red, green and blue light components, in some proportion. White light is created from equal parts of red, green, and blue light. Intensity is the brightness of the light. Attenuation is the decrease in light intensity over distance.

There are two basic kinds of light: ambient light and source light.

Ambient light determines the general illumination of a scene and keeps shadows from being completely black. This is accomplished by approximating the background lighting level caused by the reflections from each surface in the scene.

Source light comes from a light source. There are three kinds of source light: point sources (light radiates in all directions from a point source), spotlight sources (light radiates in a specified cone from a point source), and directional light (light rays arrive in the scene parallel to each other, which mimics the light from a very distant source).

Ambient light, directional light, and point light are available as GeometryBvr.ambientLight (DAGeometry.ambientLight), GeometryBvr.directionalLight(DAGeometry.DirectionalLight), and GeometryBvr.pointLight (DAGeometry.PointLight) in DirectAnimation.

Diffuse light is light that scatters from rough surfaces in all directions. Depending on the object's material, light can reflect and diffuse incoming light in varying degrees. Diffuse light characteristics are set with the GeometryBvr.diffuseColor (DAGeometry.DiffuseColor) method in DirectAnimation.

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