<table border="0" width="100%"> <tbody> <tr> <td align="center" rowspan="2"> <p> <a href="index.html"><img border="0" alt="Figure 20.06b Point Light Spheres Intensity" title="Figure 20.06b Point Light Spheres Intensity" hspace="10" src="_viewpoints/Figure20_06bPointLightSpheresIntensity.x3d._VP_Default_viewpoint.png" width="156" height="89" align="middle"/></a> </p> <p> <a href="index.html"><img border="0" alt="Figure 20.13a Directional Light Sunrise" title="Figure 20.13a Directional Light Sunrise" hspace="10" src="_viewpoints/Figure20_13aDirectionalLightSunrise.x3d._VP_Vaulted_ceiling.png" width="156" height="89" align="middle"/></a> </p> </td> <td align="left"> <p> Lights provide virtual illumination that allows objects to be seen. </p> <p> By default, you have one light in the scene, attached to your head. For more realism, you can add multiple lights: suns, light bulbs, candles, flashlights, spotlights, firelight. Lights can be positioned, oriented, and colored. Lights do not cast shadows. </p> <p> There are three types of lights: PointLight, DirectionalLight, and SpotLight. All lights have an on/off, intensity, ambient effect, and color fields. PointLight and SpotLight nodes have a location, radius, and attenuation. DirectionalLight and SpotLight nodes have a direction. </p> <p> These X3D scenes are adapted directly from the <a href="http://www.wiley.com/legacy/compbooks/vrml2sbk/toc/ch20.htm" target="_Vrml2Sourcebook">original VRML 2.0 Sourcebook chapter examples</a>. Also available: <a href="http://www.sdsc.edu/~moreland/courses/Siggraph98/vrml97/slides/mt0299.htm" target="_Vrml2SourcebookCourse">Introduction to VRML97 SIGGRAPH98 course notes</a>. </p> </td> </tr> </tbody> </table>