Chart4D
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Shows a 4 dimensional chart using Chart3D and color.

The sample creates a 3D bar or 3D surface chart with added color to
produce 4D charts - i.e. charts which show 2 independent values at each
point on a bar or surface (elevation and color).

Multiple data sets and contour data arrays are provided to show the
effects.  Zone colors can be modified at runtime through the use of a
property grid.
