From 34bb2e74fdfb35bb7d77e13bec331b798721e1f4 Mon Sep 17 00:00:00 2001
From: Revar Desmera <revarbat@gmail.com>
Date: Mon, 19 Jun 2023 20:51:31 -0700
Subject: [PATCH 1/2] Fixed edge_profile() orientations.

---
 attachments.scad | 19 +++++++++++++++++--
 1 file changed, 17 insertions(+), 2 deletions(-)

diff --git a/attachments.scad b/attachments.scad
index 835c3f6..c5ab43c 100644
--- a/attachments.scad
+++ b/attachments.scad
@@ -1722,11 +1722,26 @@ module face_profile(faces=[], r, d, excess=0.01, convexity=10) {
 //   `$idx` is set to the index number of each edge.
 //   `$attach_anchor` is set for each edge given, to the `[ANCHOR, POSITION, ORIENT, SPIN]` information for that anchor.
 //   `$profile_type` is set to `"edge"`.
+//   `$edge_angle` is set to the inner angle of the current edge.
 // Example:
 //   diff()
 //   cube([50,60,70],center=true)
 //       edge_profile([TOP,"Z"],except=[BACK,TOP+LEFT])
 //           mask2d_roundover(r=10, inset=2);
+// Example: Using $edge_angle on a Conoid
+//   diff()
+//   cyl(d1=50, d2=30, l=40, anchor=BOT) {
+//       edge_profile([TOP,BOT], excess=10, convexity=6) {
+//           mask2d_roundover(r=8, inset=1, excess=1, mask_angle=$edge_angle);
+//       }
+//   }
+// Example: Using $edge_angle on a Prismoid
+//   diff()
+//   prismoid([60,50],[30,20],h=40,shift=[-25,15]) {
+//       edge_profile(excess=10, convexity=20) {
+//           mask2d_roundover(r=5,inset=1,mask_angle=$edge_angle);
+//       }
+//   }
 
 module edge_profile(edges=EDGES_ALL, except=[], excess=0.01, convexity=10) {
     req_children($children);
@@ -1768,9 +1783,9 @@ module edge_profile(edges=EDGES_ALL, except=[], excess=0.01, convexity=10) {
                 if (!approx(pt1,pt2)) {
                     seglen = norm(pt2-pt1) + 2 * excess;
                     move(cp) {
-                        frame_map(y=-v1, z=unit(pt2-pt1)) {
+                        frame_map(x=-v2, z=unit(pt2-pt1)) {
                             linear_extrude(height=seglen, center=true, convexity=convexity)
-                                children();
+                                mirror([-1,1]) children();
                         }
                     }
                 }

From cdbfe0217c1db1ab516db06f6bd6661586d037d6 Mon Sep 17 00:00:00 2001
From: Revar Desmera <revarbat@gmail.com>
Date: Mon, 19 Jun 2023 22:36:13 -0700
Subject: [PATCH 2/2] Corrected helical gear twist calculation.

---
 gears.scad | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/gears.scad b/gears.scad
index ba1621b..eb7b7be 100644
--- a/gears.scad
+++ b/gears.scad
@@ -198,7 +198,7 @@ function spur_gear(
         p = pitch_radius(pitch, teeth),
         c = outer_radius(pitch, teeth, clearance, interior),
         r = _root_radius(pitch, teeth, clearance, interior),
-        twist = atan2(thickness*tan(helical),p),
+        twist = 360*thickness*tan(helical)/(2*PI*p),
         rgn = [
             spur_gear2d(
                 pitch = pitch,
@@ -237,7 +237,7 @@ module spur_gear(
     p = pitch_radius(pitch, teeth);
     c = outer_radius(pitch, teeth, clearance, interior);
     r = _root_radius(pitch, teeth, clearance, interior);
-    twist = atan2(thickness*tan(helical),p);
+    twist = 360*thickness*tan(helical)/(2*PI*p);
     attachable(anchor,spin,orient, r=p, l=thickness) {
         zrot(twist/2)
         linear_extrude(