<table border="0" width="100%"> <tbody> <tr> <td align="left"> <p> Authors can design interactivity into a scene that responds to user actions. </p> <p> A scene can sense when the viewer's cursor is over a shape, has touched a shape, or is dragging atop a shape. A scene can also trigger animations on a viewer's touch, enabling the viewer to move and rotate shapes. There are four main action sensor types: TouchSensor senses touch, SphereSensor senses drags in a spherical way, CylinderSensor senses drags cylindrically, and PlaneSensor senses drags around a plane. </p> <p> These X3D scenes are adapted directly from the <a href="http://www.wiley.com/legacy/compbooks/vrml2sbk/toc/ch09.htm" target="_Vrml2Sourcebook">original VRML 2.0 Sourcebook chapter examples</a>. Also available: <a href="http://www.sdsc.edu/~moreland/courses/Siggraph98/vrml97/slides/mt0161.htm" target="_Vrml2SourcebookCourse">Introduction to VRML97 SIGGRAPH98 course notes</a>. </p> </td> <td align="center" rowspan="2"> <a href="index.html"><img border="0" alt="Figure 09.6 Sphere Sensor With Axes" title="Figure 09.6 Sphere Sensor With Axes" hspace="10" src="_viewpoints/Figure09_6SphereSensorWithAxes.x3d._VP_Default_viewpoint.png" width="156" height="89" align="middle"/></a> </td> </tr> </tbody> </table>