Creating a Light Source

Use the Light command to place light sources in the drawing for realistic rendering.

To create light sources:

1. Type Light at the command prompt.
2. Specify an option:
   • Distant: Linear, parallel lights that radiate light along a line, similar to a fluorescent light bulb. Directional light emits uniform parallel light rays in one direction only. The intensity of the light does not diminish with distance. Light rays extend infinitely on either side of the insertion point of the distant light source. Distant light is used to simulate sunlight. The Distant option is equivalent to the Directionallight command.
   • Free spot: A light with a source location but no target location (default). The Free spot option is equivalent to the Nontargetlight command.
   • Point: A pointlight with a source location but no direction. A pointlight emanates light rays in all directions from a single point, similar to an incandescent light bulb. The Point option is equivalent to the Pointlight command.
   • Spot: A spotlight with a source location and a direction. A spotlight emanates light rays in a specific direction. This type of light source is similar to a stage spotlight. The Spot option is equivalent to the Spotlight command.
   • Target point: A light with a target location. The Target point option is equivalent to the Targetpointlight command.
3. Specify the source and destination locations.
4. Specify light source characteristics:
   • Attenuation: Specify the distance falloff for light sources:
     • End limit: Specifies the distance where light ends as an offset from the center of the light.
     • Start limit: Specifies the distance where light starts as an offset from the center of the light.
     • Type: Lets you set an attenuation type:
       • Inverse linear: Applies linear falloff where the brightness caused by the light source decreases inversely to the distance.
       • Inverse squared: Applies quadratic falloff where the brightness caused by the light source decreases inversely to the square of the distance. Inverse squared attenuation decreases performance because the parameter requires more calculation.
       • None: Specifies no light source falloff.
     • Use Limits: Determines whether to use limits.
   • Color: Specifies the color of the light source.
   • Intensity: Sets the brightness of emitted light. Type a value between 0.00 and the maximum value which your system supports (0.00-max float, 1.0000 by default).
   • Name: Lets you name the light source. Give each light a unique name. The maximum length is 256 characters. The name can include uppercase and lowercase letters, numbers, spaces, hyphens (-), and underscores (_).
   • Shadow: Specifies whether the light source casts shadows. Shadows can be Sharp with sharp edges or Soft with realistic edges.
   • Status: Specifies whether the light source is on or off.
5. Specify the Exit option to create the light source.

   The light source displays in the graphics area.

Access

Command: Light