Removed spurious convexity in difference from rounded_polygon().

CHANGELOG.md

@@ -3,6 +3,16 @@
 This changelog is generated by `changelog.py` using manually added semantic version tags to classify commits as breaking changes, additions or fixes.
 
 
+### [v15.13.0](https://github.com/nophead/NopSCADlib/releases/tag/v15.13.0 "show release") Additions [...](https://github.com/nophead/NopSCADlib/compare/v15.12.0...v15.13.0 "diff with v15.12.0")
+*   2021-05-02 [`3401919`](https://github.com/nophead/NopSCADlib/commit/34019196cdac6b08e57d773e138a22394b609ea5 "show commit") [C.P.](# "Chris Palmer") Updated readme
+
+*   2021-05-02 [`436fc71`](https://github.com/nophead/NopSCADlib/commit/436fc71cf319c1e71b6cbd240b76d7cad5ecd8ba "show commit") [M.B.](# "Martin Budden") Added `blower_size` function.
+
+### [v15.12.0](https://github.com/nophead/NopSCADlib/releases/tag/v15.12.0 "show release") Additions [...](https://github.com/nophead/NopSCADlib/compare/v15.11.1...v15.12.0 "diff with v15.11.1")
+*   2021-04-26 [`e2feceb`](https://github.com/nophead/NopSCADlib/commit/e2feceb608b4491424c0e4c1e7c191f7d8aeceec "show commit") [C.P.](# "Chris Palmer") Updated readme
+
+*   2021-04-25 [`9c1a9bf`](https://github.com/nophead/NopSCADlib/commit/9c1a9bf3572c07a57b5bd1fde1d9a4aba14e5ea8 "show commit") [M.B.](# "Martin Budden") Add facility to orient `core_xy` with left motor being lower or upper motor.
+
 #### [v15.11.1](https://github.com/nophead/NopSCADlib/releases/tag/v15.11.1 "show release") Fixes [...](https://github.com/nophead/NopSCADlib/compare/v15.11.0...v15.11.1 "diff with v15.11.0")
 *   2021-04-25 [`feec1e7`](https://github.com/nophead/NopSCADlib/commit/feec1e7ae5a5217586e0ab9e7b002e8af8f7c749 "show commit") [C.P.](# "Chris Palmer") Updated readme.
 

readme.md

@@ -373,6 +373,7 @@ Models of radial blowers.
 |:--- |:--- |
 | `blower_casing_is_square(type)` | True for square radial fans, false for spiral shape radial blowers |
 | `blower_exit_offset(type)` | Offset of exit's centre from the edge |
+| `blower_size(type)` | Size |
 
 ### Modules
 | Module | Description |

utils/rounded_polygon.scad

@@ -77,7 +77,7 @@ module rounded_polygon(points, _tangents = undef) { //! Draw the rounded polygon
     indices = [0 : len - 1];
     tangents = [ for (t = _tangents ? _tangents : rounded_polygon_tangents(points)) each [t.x, t.y] ];
 
-    difference(convexity = points) {
+    difference() {
         union() {
             for(i = indices)
                 if(points[i][2] > 0)

vitamins/blower.scad

@@ -28,6 +28,7 @@ use <screw.scad>
 function blower_length(type)      = type[2]; //! Length of enclosing rectangle
 function blower_width(type)       = type[3]; //! Width of enclosing rectangle
 function blower_depth(type)       = type[4]; //! Height
+function blower_size(type)        = [blower_length(type), blower_width(type), blower_depth(type)]; //! Size
 function blower_bore(type)        = type[5]; //! The air intake hole diameter
 function blower_screw(type)       = type[6]; //! The type of screws needed
 function blower_hub(type)         = type[7]; //! Rotor hub diameter