doc fixes

gears.scad

@@ -197,7 +197,10 @@ function _inherit_gear_thickness(thickness,dflt=10) =
 //   can also be used to fine tune the spacing between gears.  When the gear has many teeth a negative profile shift may
 //   be able to bring the gears slightly closer together, while still avoiding undercutting.
 //   Profile shifting also changes the effective pressure angle of the gear engagement.
-//   .
+// Figure(2D,Med,NoAxes): The green gear is a 7 tooth gear without profile shifting.  In yellow is the same gear, profile shifted.  Note that the teeth too longer narrow at their base.  Also note that the effective root circle has a larger radius, and the teeth are also longer.
+//   spur_gear2d(mod=5, teeth=7);
+//   color("green")spur_gear2d(mod=5, teeth=7, profile_shift=0);
+// Continues:
 //   The minimum number of teeth to avoid undercutting is 17 for a pressure angle of 20, but it is 32 for a pressure
 //   angle of 14.5 degrees.  It can be computed as `2/(sin(alpha))^2` where `alpha` is the pressure angle.
 //   By default, the gear modules produce corrected gears.  You can override this by specifying the profile shift

masks2d.scad

@@ -858,7 +858,6 @@ function mask2d_dovetail(edge, angle, slope, shelf=0, inset=0, mask_angle=90, ex
 //   mask2d_ogee(pattern, [excess], ...) [ATTAHCMENTS];
 // Usage: As Function
 //   path = mask2d_ogee(pattern, [excess], ...);
-//
 // Description:
 //   Creates a 2D Ogee mask shape that is useful for extruding into a 3D mask for a 90° edge.
 //   Conversely, you can use that same extruded shape to make an interior ogee decoration between two walls at a 90º angle.