The Relative Distance node converts the distance to the origin from one of the specified reference transformations into a greyscale texture (figure 1).
Figure 1: The Relative Distance node used to alter diffuse color using the Y-axis offset
Distance Mode - Returns the Euclidean distance between the shaded point and the origin of the specified reference transform.
Reference Transform - Transform defining the coordinate system used to compute the distance metric.
Use Full Transform - If Enabled, the distances will be calculated after applying the full reference transform, including scale and rotation. If Disabled, only the translation is taken into account.
Normalize Results - Takes the result and normalizes the values between 0 and 1.
Normalization Range - Defines the minimum and maximum of the normalization range.