<!DOCTYPE html
  PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">

<!--
Copyright (c) 2006 UGS Corp.

All Rights Reserved.

This software and related documentation are proprietary to UGS Corp.
-->
<html>
   <head>
      <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
      <title>Dynamic Light Positioning</title>
      <script language="javaScript">
        abridged="false";
        displayConditions=new Array();
      </script>
      <link type="text/css" href="../css/main_styles.css" rel="stylesheet">
   </head>
   <body class="bodydocs" onload="top.pageLoader()" bgcolor="#FFFFFF">
      <div class="title_topic5" id="xps10_pagetitle">Dynamic Light Positioning</div>
      <hr noshade="true">
      <p class="para_topic">You can use the dynamic light positioning icons to move the lights inside the display window. Click and drag on the light objects displayed in the work view. You can perform five operations:</p>
      <table cellspacing="3" align="center">
         <tr>
            <th bgcolor="#c0c0c0" colspan="1" rowspan="1" valign="middle">
               <p class="para_th">Option</p>
            </th>
            <th bgcolor="#c0c0c0" colspan="1" rowspan="1" valign="middle">
               <p class="para_th">Icon</p>
            </th>
            <th bgcolor="#c0c0c0" colspan="1" rowspan="1" valign="middle">
               <p class="para_th">Description</p>
            </th>
         </tr>
         <tr>
            <td bgcolor="#f4f4f4" colspan="1" rowspan="1" valign="middle">
               <p class="para_td">Drag Target</p>
            </td>
            <td bgcolor="#f4f4f4" colspan="1" rowspan="1" valign="middle">
               <p align="center"><img align="bottom" src="graphics/vie_lighttarget.gif"></p>
            </td>
            <td bgcolor="#f4f4f4" colspan="1" rowspan="1" valign="middle">
               <p class="para_td">Repositions the destination point of the light beam while the source point remains stationary. For spotlights only.</p>
            </td>
         </tr>
         <tr>
            <td bgcolor="#f4f4f4" colspan="1" rowspan="1" valign="middle">
               <p class="para_td">Rotate Source</p>
            </td>
            <td bgcolor="#f4f4f4" colspan="1" rowspan="1" valign="middle">
               <p align="center"><img align="bottom" src="graphics/vie_lightrotate.gif"></p>
            </td>
            <td bgcolor="#f4f4f4" colspan="1" rowspan="1" valign="middle">
               <p class="para_td">Rotates the source point while keeping the destination point stationary. For Spotlights, it keeps the distance between the source point and the destination point constant. For Distant lights, this option rotates the direction vector. For Point lights, this option rotates the source point while keeping the distance between the source and the origin constant.</p>
            </td>
         </tr>
         <tr>
            <td bgcolor="#f4f4f4" colspan="1" rowspan="1" valign="middle">
               <p class="para_td">Drag Source</p>
            </td>
            <td bgcolor="#f4f4f4" colspan="1" rowspan="1" valign="middle">
               <p align="center"><img align="bottom" src="graphics/vie_lightsource.gif"></p>
            </td>
            <td bgcolor="#f4f4f4" colspan="1" rowspan="1" valign="middle">
               <p class="para_td">For Spotlights, this operation allows you to reposition the source point of the light beam while the destination point stays stationary. For Point lights, this operation allows you to move the source point. This provides a method for moving the light source on a fixed plane parallel to the screen.</p>
            </td>
         </tr>
         <tr>
            <td bgcolor="#f4f4f4" colspan="1" rowspan="1" valign="middle">
               <p class="para_td">Drag Direction Vector</p>
            </td>
            <td bgcolor="#f4f4f4" colspan="1" rowspan="1" valign="middle">
               <p align="center"><img align="bottom" src="graphics/vie_lightvector.gif"></p>
            </td>
            <td bgcolor="#f4f4f4" colspan="1" rowspan="1" valign="middle">
               <p class="para_td">For Spotlights, this operation moves both the source point and the destination point at the same time, keeping both the angle and the distance between them constant. For Distant lights, this operation drags the source, keeping the direction vector constant. For Distant lights you can use this option to move your light object to a desired position. However, dragging a Distant light's direction vector will not change the lighting effect in the view since the light direction doesn't change.</p>
            </td>
         </tr>
         <tr>
            <td bgcolor="#f4f4f4" colspan="1" rowspan="1" valign="middle">
               <p class="para_td">Stretch Spot Cone</p>
            </td>
            <td bgcolor="#f4f4f4" colspan="1" rowspan="1" valign="middle">
               <p align="center"><img align="bottom" src="graphics/vie_lightcone.gif"></p>
            </td>
            <td bgcolor="#f4f4f4" colspan="1" rowspan="1" valign="middle">
               <p class="para_td">Changes the angle of the cone of light emitted by a Spotlight.</p>
            </td>
         </tr>
      </table><br><table border="0">
         <tr>
            <td valign="top" align="left"><img align="left" src="../graphics/note.gif" alt="Note" title="Note"></td>
            <td valign="bottom" align="left" width="100%">
               <div class="para_note">
                  <p class="para_note_body">  Keep the starting position of Point and Spot type lights close to the model. This way you will prevent the light object display from being clipped away by the view's clipping planes, and you may find that it's easier to move lights dynamically when they're closer to the part.</p>
               </div>
            </td>
         </tr>
      </table>
   </body>
</html>