Mike, you need to use the mask feature available for surfaces.
1. Create a polyline that encompasses each of the areas that are to be rendered separately.
2. Create an Outside, render only mask using each polyline.
When viewing in 3d, be sure you select the Realistic render mode and you'll see your surface rendered with a different look for each masked area.
Warning, save your drawing before using the Object Viewer with masks enabled. I have had this crash several times and considering the time it can take to draw a polyline from point to point to point to point, you might save yourself some frustration by being sure to save.
Best regards,
Tim Corey
Delta Engineering Systems
Redding, CA
Tim Corey
MicroCAD Training and Consulting, Inc.
Redding, CA
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