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      <title>Light Source Parameters</title>
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      <div class="title_topic5" id="xps10_pagetitle">Light Source Parameters</div>
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      <p class="para_topic">The following parameters are used when specifying a light source in high quality shading. Not all the parameters are used with all types of lights; for example, parameters that deal with shadows are not used on eye light sources, since that light cannot generate shadows.</p>
      <div class="title_division">Beam Fall Off</div>
      <p class="para_division">Determines the fall off ratio from within the cone described by &quot;Cone Angle&quot;. Possible values are None, Gradual, or Rapid.</p>
      <div class="title_division">Cone Angle</div>
      <p class="para_division">This is the angle of the cone within which light is emitted for a spot light. The angle is a floating point value measured in degrees with a range of 0.0 to 180.0.</p>
      <div class="title_division">Delta Angle</div>
      <p class="para_division">The angular distance inside &quot;Cone Angle&quot; in which the emitted light begins to fall off. The angle is a floating point value measured in degrees ranging from 0.0 to 180.0. The light begins to fall off in the spot light at an angle defined by &quot;Cone Angle - Cone Delta Angle&quot;, and the light intensity reaches zero at &quot;Cone Angle&quot;.</p>
      <div class="title_division">Intensity</div>
      <p class="para_division">All light sources contain an intensity parameter. The intensity is the brightness of the light source. This is a floating point parameter with a positive value, and is normally between 0.0 and 1.0. The maximum value allowed is 100.0.</p>
      <div class="title_division">Position</div>
      <p class="para_division">Determines if the XYZ coordinates for the light source positions are Fixed with the Part (i.e., the Work Coordinate System of the part), or Fixed to Observer (i.e., in screen space). When Fixed to Part is active, the light source remains fixed with respect to the WCS. When Fixed to Observer is active, the light source is fixed to the observer (in screen space), and not to the WCS of the part. Screen space is defined as +X to the right, +Y up and +Z out of the screen.</p>
      <div class="title_division">Shadows</div>
      <p class="para_division">Controls the generation of shadow information for a particular light source, and can be turned on by selecting the check box. Shadows are only calculated and used if this parameter is on for an individual light source, and shadows are requested in the Setup dialog.</p>
      <div class="title_division">Shadow Detail</div>
      <p class="para_division">The resolution of shadows. There are five options offered: Coarse, Standard, Fine, Extra Fine, and Raytraced. Raytraced produces the sharpest and highest quality shadows. Coarse produces low quality shadows, which is fine for previewing shades (although that level of shadow can result in a sort of checkerboard pattern).</p>
      <div class="title_division">Shadow Edges</div>
      <p class="para_division">The softness of the edges of the shadows. The available options are Hard, Standard Soft, Extra Soft, and Ultra Soft. </p>
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