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            <td width="76%"><div align="center"><span class="style2"><font color="#0000A0">Lighting</font></span></div></td>
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        <p class="Normal">You can light a scene with distant lights (which act like point-like lamps far from the scene) and/or local lights (point-like lamps near the scene, like the yellow light shown above). For a distant light you specify its direction from the origin. For a local light you specify its location in the scene.</p>
        <p class="Normal"><span class="attributes">There is a list of all distant and local light
            objects, </span><span class="attribute">scene.lights</span><span class="attributes">. By default, </span><span class="attribute">scene.lights</span><span class="attributes"> is this list:<br />
                        </span></p>
        <p class="program style6"> [distant_light(direction=vector( 0.22, &nbsp;0.44, &nbsp;0.88), &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;color=color.gray(0.8)),<br />
  &nbsp;distant_light(direction=vector(-0.88, -0.22, -0.44),
          &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;color=color.gray(0.3))]</p>
        <p class="Normal">You can get rid of these default lights by setting the list to empty with <span class="attribute">scene.lights
              = []</span>.</p>
        <p class="Normal">You can turn a light on or off by setting <span class="attribute">visible</span> to True or False.</p>
        <p class="Normal">In addition to these default distant lights, there is default ambient lighting in the form of <font color="#FF0000">scene.ambient=color.gray(0.2)</font>. The
          color of light objects and the amount of <font color="#FF0000">scene.ambient</font> must
          be specified with some care, because if the total lighting intensity
        exceeds 1 anywhere in the scene the results are unpredictable.</p>
        <p class="Normal">The following statement creates a local yellow light whose <em>position</em> is at
            (x,y,z), and if you continually update lamp.pos, the light will move.
        You may wish to place a sphere or box with <span class="attribute">emissive=True</span> at the same location so that the lamp looks like a glowing lamp.</p>
        <p class="program"> lamp = local_light(pos=vector(x,y,z), <br />
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;        color=color.yellow)</p>
        <p class="Normal">A distant red light located in the <em>direction</em> (x,y,z) from the origin is created like this:</p>
        <p class="program">distant_light(direction=vector(x,y,z), color=color.red)</p>
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