Added an example of how to use the sweep operation.

CadQuery/Examples/Ex031_Sweep.py

@@ -0,0 +1,42 @@
+# This example is meant to be used from within the CadQuery module for FreeCAD
+import cadquery
+from Helpers import show
+
+# Points we will use to create spline and polyline paths to sweep over
+pts = [
+    (0, 1),
+    (1, 2),
+    (2, 4)
+]
+
+# Spline path generated from our list of points (tuples)
+path = cadquery.Workplane("XZ").spline(pts)
+
+# Sweep a circle with a diameter of 1.0 units along the spline path we just created
+defaultSweep = cadquery.Workplane("XY").circle(1.0).sweep(path)
+
+# Sweep defaults to making a solid and not generating a Frenet solid. Setting Frenet to True helps prevent creep in
+# the orientation of the profile as it is being swept
+frenetShell = cadquery.Workplane("XY").circle(1.0).sweep(path, makeSolid=False, isFrenet=True)
+
+# We can sweep shapes other than circles
+defaultRect = cadquery.Workplane("XY").rect(1.0, 1.0).sweep(path)
+
+# Switch to a polyline path, but have it use the same points as the spline
+path = cadquery.Workplane("XZ").polyline(pts)
+
+# Using a polyline path leads to the resulting solid having segments rather than a single swept outer face
+plineSweep = cadquery.Workplane("XY").circle(1.0).sweep(path)
+
+# Switch to an arc for the path
+path = cadquery.Workplane("XZ").threePointArc((1.0, 1.5), (0.0, 1.0))
+
+# Use a smaller circle section so that the resulting solid looks a little nicer
+arcSweep = cadquery.Workplane("XY").circle(0.5).sweep(path)
+
+# Translate the resulting solids so that they do not overlap and display them left to right
+show(defaultSweep)
+show(frenetShell.translate((5, 0, 0)))
+show(defaultRect.translate((10, 0, 0)))
+show(plineSweep.translate((15, 0, 0)))
+show(arcSweep.translate((20, 0, 0)))