Creating 3D Geometry - AutoCAD 2011 and AutoCAD LT 2011: No Experience Required - page 854

5. Make a similar extruded threshold for the sliding-glass door.
6. Make the A-FLOR-3DOB layer current. To create the floor, first draw
a polyline around the inside perimeter of the cabin, ignoring the inte-
rior walls and thresholds.
7. Start the EXTRUDE command, select the floor polyline, and then
extrude it 1 ″ (25 mm) (see Figure 16.28).
FiGuRE 16.28 The 3D floor with the thresholds
Creating the Foundation and Supports
The cabin's foundation is an 18 ″ (457 mm)-thick concrete slab that sits directly
on the ground. The foundation supports the structure except where the pop-out
projects out from the side wall. At the outside corners of each deck are concrete
support posts. All the objects are placed on the 3D-Foundation layer.
1. Make the A-FNDN-3DOB layer current, and thaw the A-DECK layer.
2. Freeze the A-FLOR-3DOB and A-DOOR-THRE-3DOB layers.
3. Draw a closed polyline around the outside perimeter of the cabin, mak-
ing sure you span the pop-out area as if it didn't exist. Alternatively, you
could use the RECTANGLE command.
4. Extrude the polyline 18 ″ (457 mm) in the negative Z direction. You can
do this with Dynamic Input active by dragging the extrusion in the