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These two attributes allows adjusting the contribution of the light to the diffuse or specular shading components. Setting For instance, setting Diffuse Contribution to 0 makes the light a purely specular one. It ; it has the same effect as turing of off the light's Emit Diffuse control.
Please note that turning off Emit Diffuse will make Diffuse Contribution controls insensitive; in a similar fashion, turning off Emit Specular will make the Specular Contribution controls insensitive. The Emit Diffuse and Emit Specular controls are located in the light shape's main attribute section, a bit below the light's Intensity control.
The Emit Diffuse and Emit Specular controls , which must be enabled to allow adjusting the Diffuse Contribution and Specular Contribution, respectively.
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