The lighting angle of the light source with a clockwise value starting at the top.
The bevel depth controls how elevated the result should look. A lower value means a flatter surface.
Distance defines the width of the bevel effect. A smaller value means that only the edge of the surface will be bevelled.
The spread is a smoothing mechanism that softens the bevel edge.
The highlight value controls the highlight brightness.
The shadow value controls the amount of blackening of the light shadow.
Light angle defines the height angle of the light source. A value of +-90 means that the light is in the screen plane horizon while a value of 0 degrees is zenith.
The specularity controls how shiny the objects appear. Higher values means narrower specular spots while lower values means broader highlights.