Headlight
A headlight is a directional light that points to the scene from the camera position. The Headlight () is similar to the Directional Light with the only difference being that it is always locked to the camera’s coordinate system and a direction pointing from the camera is used. To add a Headlight node:
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In the Model Builder, under Definitions click View. In the View toolbar, click Headlight, or
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Right-click the View node and select Headlight.
Figure 6-25 is an example of one Headlight node added to a View with the Directional Light nodes enabled. The headlight’s position and direction cannot be changed; it is based on the Directional Light node’s (or nodes’) x, y, and z coordinates. You can adjust the light and specular intensity levels and the color as needed.
You can convert a headlight to a directional light by right-clicking the Headlight node and select Convert to Directional Light.
Figure 6-25: An example of a blue Headlight source with three Directional light sources set to white. If the geometry is rotated, you can adjust and view the effects of the Headlight source on the geometry based on the shades of blue and white.
Settings
Adjust the settings such as the intensity and color of the headlight.
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Enter a Light Intensity or use the slider to select values. Watch the changes in the Graphics window at the same time to help choose a level. When adjusting the light intensity, the light marker changes in length as the corresponding intensity is changed on the object.
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Enter a Specular intensity (the intensity of the light that reflects off the surface of the geometry and used to define spheres and curves). This setting is turned ON and OFF on the View page (the default is ON), and the levels are adjusted for each Specular intensity using the field or the slider to select values between 0 and 1 (default value: 1). Watch the changes in the Graphics window at the same time to help choose a level. See Figure 6-20 for an example of specular light.
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Select a Color: White (default), Custom, Black, Blue, Cyan, Green, Magenta, Red, or Yellow. If you select Custom, click the Color button to choose a color from the Custom color palette.
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By default, the Show light marker is selected. The light marker is associated to the type of light applied to the object. See Figure 6-21 for examples. Click to clear the check box as needed and remove the marker from the Graphics window.
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By default, the Cast shadows check box is selected. The headlight will then cast shadows when the direct shadows are active (requires the OpenGL renderer, optimized for quality). Clear the check box if you do not want the light to cast shadows.