Merge branch 'martinbudden-pulley_children'

CHANGELOG.md

@@ -3,6 +3,9 @@
 This changelog is generated by `changelog.py` using manually added semantic version tags to classify commits as breaking changes, additions or fixes.
 
 
+### [v15.4.0](https://github.com/nophead/NopSCADlib/releases/tag/v15.4.0 "show release") Additions [...](https://github.com/nophead/NopSCADlib/compare/v15.3.1...v15.4.0 "diff with v15.3.1")
+*   2021-04-02 [`b2d712b`](https://github.com/nophead/NopSCADlib/commit/b2d712bca94165a338e5f904880d12f9c4c5ecd0 "show commit") [C.P.](# "Chris Palmer") Added `quadratic_real_roots()` and `cubic_real_roots()`.
+
 #### [v15.3.1](https://github.com/nophead/NopSCADlib/releases/tag/v15.3.1 "show release") Fixes [...](https://github.com/nophead/NopSCADlib/compare/v15.3.0...v15.3.1 "diff with v15.3.0")
 *   2021-04-02 [`f3376ed`](https://github.com/nophead/NopSCADlib/commit/f3376edaf186b32f442b94d6d0b42f1ba0c7612c "show commit") [C.P.](# "Chris Palmer") Documented `xor()` function.
 

readme.md

@@ -2699,7 +2699,7 @@ Timing belt pulleys, both toothed and plain with internal bearings for idlers.
 ### Modules
 | Module | Description |
 |:--- |:--- |
-| `pulley(type, colour = silver)` | Draw a pulley |
+| `pulley(type, colour = silver)` | Draw a pulley, any children are placed above. |
 | `pulley_assembly(type, colour = silver)` | Draw a pulley with its grub screws in place |
 
 ![pulleys](tests/png/pulleys.png)

vitamins/pulley.scad

@@ -53,7 +53,7 @@ function pulley_extent(type) = max(pulley_flange_dia(type), pulley_hub_dia(type)
 T_angle = 40;
 GT_r = 0.555;
 
-module pulley(type, colour = silver) { //! Draw a pulley
+module pulley(type, colour = silver) { //! Draw a pulley, any children are placed above.
     teeth = pulley_teeth(type);
     od = pulley_od(type);
 
@@ -138,6 +138,10 @@ module pulley(type, colour = silver) { //! Draw a pulley
         else
             core();
     }
+
+    if($children)
+        translate_z(pulley_height(type))
+            children();
 }
 
 module pulley_assembly(type, colour = silver) { //! Draw a pulley with its grub screws in place