From 155d5b879c568a8bb5b7fa9f582ba587e0c8e1c9 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?J=C3=BCrg=20Lehni?= <juerg@scratchdisk.com>
Date: Wed, 8 Mar 2017 13:41:23 +0100
Subject: [PATCH] Improve Path._addSquareCap() for use in path offsetting code.

---
 src/path/Path.js | 15 ++++++++-------
 1 file changed, 8 insertions(+), 7 deletions(-)

diff --git a/src/path/Path.js b/src/path/Path.js
index 38ca020b..43b8de85 100644
--- a/src/path/Path.js
+++ b/src/path/Path.js
@@ -1721,7 +1721,7 @@ var Path = PathItem.extend(/** @lends Path# */{
         }
 
         function checkSegmentStroke(segment) {
-            // Handle joins / caps that are not round specificelly, by
+            // Handle joins / caps that are not round specifically, by
             // hit-testing their polygon areas.
             var isJoin = closed || segment._index > 0
                     && segment._index < numSegments - 1;
@@ -2834,19 +2834,20 @@ statics: {
         // Style#strokeScaling.
         var point = segment._point.transform(matrix),
             loc = segment.getLocation(),
-            normal = loc.getNormal().multiply(radius).transform(strokeMatrix);
+            // Checking loc.getTime() for 0 is to see whether this is the first
+            // or the last segment of the open path, in order to determine in
+            // which direction to flip the normal.
+            normal = loc.getNormal()
+                    .multiply(loc.getTime() === 0 ? radius : -radius)
+                    .transform(strokeMatrix);
         // For square caps, we need to step away from point in the direction of
         // the tangent, which is the rotated normal.
-        // Checking loc.getTime() for 0 is to see whether this is the first
-        // or the last segment of the open path, in order to determine in which
-        // direction to move the point.
         if (cap === 'square') {
             if (isArea) {
                 addPoint(point.subtract(normal));
                 addPoint(point.add(normal));
             }
-            point = point.add(normal.rotate(
-                    loc.getTime() === 0 ? -90 : 90));
+            point = point.add(normal.rotate(-90));
         }
         addPoint(point.add(normal));
         addPoint(point.subtract(normal));