From f142f045aa4e0704a137f1155839d2414d93ef16 Mon Sep 17 00:00:00 2001
From: Patrick Walton <pcwalton@mimiga.net>
Date: Tue, 31 Mar 2020 13:30:50 -0700
Subject: [PATCH] Detect coincident points and bail out of the line join code
 as necessary.

---
 content/src/stroke.rs | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/content/src/stroke.rs b/content/src/stroke.rs
index d9a5d446..9f6d8ad2 100644
--- a/content/src/stroke.rs
+++ b/content/src/stroke.rs
@@ -375,6 +375,10 @@ impl Contour {
         let (p0, p1) = (self.position_of_last(2), self.position_of_last(1));
         let prev_tangent = LineSegment2F::new(p0, p1);
 
+        if prev_tangent.square_length() < EPSILON || next_tangent.square_length() < EPSILON {
+            return;
+        }
+
         match join {
             LineJoin::Bevel => {}
             LineJoin::Miter(miter_limit) => {