Merge pull request #1437 from adrianVmariano/master

attach() bugfix

attachments.scad

@@ -779,7 +779,7 @@ function _make_anchor_legal(anchor,geom) =
 //   .
 //   If you give `inside=true` then the anchor arrows are lined up so they are pointing the same direction and
 //   the child object will be located inside the parent.  In this case a default "remove" tag is applied to
-//   the children.
+//   the children.  
 //   .
 //   Because the attachment process forces an orientation and anchor point for the child, it overrides
 //   any such specifications you give to the child:  **both `anchor=` and `orient=` given to the child are
@@ -797,10 +797,17 @@ function _make_anchor_legal(anchor,geom) =
 //   These options will probably be necessary, in fact, to get the child correctly positioned.  Note that
 //   giving `spin=` to `attach()` in this case is the same as applying `zrot()` to the child. 
 //   .
-//   Attached children may be ovarlapped into the parent a bit, as given by the `$overlap` value
+//   You can overlap attached children into the parent by giving the `$overlap` value
 //   which is 0 by default, or by the `overlap=` argument.    This is to prevent OpenSCAD
 //   from making non-manifold objects.  You can define `$overlap=` as an argument in a parent
-//   module to set the default for all attachments to it.
+//   module to set the default for all attachments to it.  When you give `inside=true`, a positive overlap
+//   value shifts the child object outward.
+//   .
+//   If you specify an `inset=` value then the child is shifted away from any edges it is aligned to, towards the middle
+//   of the parent.  The `shiftout=` parameter is intended to simplify differences with aligned objects
+//   placed inside the parent.  It will shift the child outward along every direction where it is aligned with
+//   the parent.  For an inside child this is equivalent to giving a positive overlap and negative inset value.
+//   For a child with `inside=false` it is equivalent to a negative overlap and negative inset.  
 //   .
 //   For a step-by-step explanation of
 //   attachments, see the [Attachments Tutorial](Tutorial-Attachments).
@@ -916,7 +923,7 @@ module attach(parent, child, overlap, align, spin=0, norot, inset=0, shiftout=0,
         anchor_data = _find_anchor(anchor, $parent_geom);
         anchor_pos = anchor_data[1];
         anchor_dir = factor*anchor_data[2];
-        anchor_spin = !inside || anchor_data[3]==0 ? anchor_data[3] : 180+anchor_data[3];
+        anchor_spin = !inside || anchor==TOP || anchor==BOT ? anchor_data[3] : 180+anchor_data[3];
         $anchor=anchor;
         for(align_ind = idx(align_list)){
             align = is_undef(align_list[align_ind]) ? undef

beziers.scad

@@ -1455,14 +1455,18 @@ function bezier_patch_normals(patch, u, v) =
 // Usage:
 //   debug_bezier(bez, [size], [N=]);
 // Description:
-//   Renders 2D or 3D bezier paths and their associated control points.
-//   Useful for debugging bezier paths.
+//   Renders 2D or 3D bezier paths and their associated control points to help debug bezier paths. 
+//   The endpoints of each bezier curve in the bezier path are marked with a blue circle and the intermediate control
+//   points with a red plus sign.  For cubic (degree 3) bezier paths, the module displays the standard representation
+//   of the control points as "handles" at each endpoint.  For other degrees the control points are drawn as
+//   a polygon.  You can of course give a single bezier curve as input, but you must in that case explicitly specify
+//   the bezier degree when it is not a cubic bezier.  
 // Arguments:
 //   bez = the array of points in the bezier.
 //   size = diameter of the lines drawn.
 //   ---
-//   N = Mark the first and every Nth vertex after in a different color and shape.
-// Example(2D):
+//   N = The degree of the bezier curves.  Cubic beziers have N=3.  Default: 3
+// Example(2D): Cubic bezier path
 //   bez = [
 //       [-10,   0],  [-15,  -5],
 //       [ -5, -10],  [  0, -10],  [ 5, -10],
@@ -1470,6 +1474,15 @@ function bezier_patch_normals(patch, u, v) =
 //       [  5,  10],  [  0,  10]
 //   ];
 //   debug_bezier(bez, N=3, width=0.5);
+// Example(2D): Quartic (degree 4) bezier path
+//   bez = [
+//       [-10,   0],  [-15,  -5],
+//       [ -9, -10],  [  0, -12],  [ 5, -10],
+//       [ 14,  -5],  [ 18,   0],  [16,   5],
+//       [  5,  10] 
+//   ];
+//   debug_bezier(bez, N=4, width=0.5);
+
 module debug_bezier(bezpath, width=1, N=3) {
     no_children($children);
     check = 

shapes3d.scad

@@ -130,6 +130,10 @@ function cube(size=1, center, anchor, spin=0, orient=UP) =
 //   orient = Vector to rotate top towards.  See [orient](attachments.scad#subsection-orient).  Default: `UP`
 // Example: Simple regular cube.
 //   cuboid(40);
+// Example: Cuboid with a corner at the origin
+//   cuboid(40, anchor=FRONT+LEFT+BOT);
+// Example: Cuboid anchored on its right face
+//   cuboid(40, anchor=RIGHT);
 // Example: Cube with minimum cornerpoint given.
 //   cuboid(20, p1=[10,0,0]);
 // Example: Rectangular cube, with given X, Y, and Z sizes.