What is the difference between the five attenuation methods in 3D?

The attenuation map generates values from white to black according to the angular attenuation of the normal above the geometric surface. The direction used to specify the angular attenuation will vary with the selected method. However, by default, the map will generate white on faces whose normals point to the outside of the current view and black on faces whose normals are parallel to the current view.

By default, Front: Side is the name of the group at the top of the rollout. Front: The side indicates "vertical/parallel" attenuation. The name will change depending on the attenuation type selected. In any case, the name on the left refers to the top set of controls, while the name on the right refers to the bottom set of controls.

Control is as follows:

Click the color swatch to specify a color.

Use numeric fields and spinners to adjust the relative intensity of colors.

Click the button labeled None to specify the map.

Enable the check box to activate the map; Otherwise, the color will be used. By default, these are enabled.

Click Swap Colors/Maps (curved arrows) to swap these assignments.

Select the attenuation type. There are five options available:

1 Vertical/Parallel Sets the angular attenuation range between the surface normal perpendicular to the attenuation direction and the normal parallel to the attenuation direction. Based on the normal direction of the face, the attenuation range is 90 degrees. (Default setting. )

2 Direction/Deviation Sets the angular attenuation range between the surface normal facing (parallel to) the attenuation direction and the normal deviating from the attenuation direction. Based on the change of surface normal direction, the attenuation range is 180 degrees.

Fresnel adjustment based on refractive index (IOR). A dim reflection is produced on the surface facing the view, and a brighter reflection is produced on the angled surface, just like a highlight on a glass surface.

4 Shadows/lights are adjusted between two sub-textures according to the light falling on the object.

5 Distance blending adjusts between two sub-textures according to the near distance value and the far distance value. Uses include reducing anti-aliasing on large terrain objects and controlling coloring in non-photorealistic environments.

Select the direction of attenuation. There are five options available:

1 viewing direction (camera z axis) sets the attenuation direction relative to the camera (or screen). Changing the orientation of an object does not affect the attenuation map. (Default setting. )

The X/Y axis of a camera is similar to the z axis of a camera. For example, using the camera's X axis for the towards/away attenuation type will gradually change from left (towards) to right (away).

3 Object Use an object whose position can determine the attenuation direction. Click the Width button next to Object in the Mode Specific Parameters group, and then pick the object in the scene. The attenuation direction is the direction from the shadow point to the center of the object. Points facing the center side of the object get the "direction" value, while points facing away from the object get the "deviation" value.

4 Local X/Y/Z Axis Sets the attenuation direction to the local axis of one of the objects. Changing the direction of the object changes the direction of the attenuation.

5 World X/Y/Z Axis Sets the attenuation direction as one of the axes of the world coordinate system. Changing the orientation of an object does not affect the attenuation map.

When no object is selected, the attenuation direction uses the local x, y or z axis of the colored object.