From 70769c9d7ec655d923cb2398edbdfcf28b8e4526 Mon Sep 17 00:00:00 2001
From: Josh Dersch <joshd@livingcomputermuseum.org>
Date: Thu, 8 Jun 2017 10:28:22 -0700
Subject: [PATCH] Updated workaround for mouse issue on OS X Sierra

---
 Contralto/SdlUI/SdlAltoWindow.cs | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/Contralto/SdlUI/SdlAltoWindow.cs b/Contralto/SdlUI/SdlAltoWindow.cs
index 25ae93a..5bdceb1 100644
--- a/Contralto/SdlUI/SdlAltoWindow.cs
+++ b/Contralto/SdlUI/SdlAltoWindow.cs
@@ -364,10 +364,12 @@ namespace Contralto.SdlUI
         private void MouseDown(byte button, int x, int y)
         {
             //
-            // OS X issue: we get mousedown events when the window title
-            // is clicked, sometimes.  So ignore those.
+            // OS X Sierra issue: we get mousedown events when the window title
+            // is clicked, sometimes.  These always show up with a Y coordinate
+            // of zero.  So ignore those only for mouse-capture purposes as
+            // a workaround.
             //
-            if (x < 0 || y < 0)
+            if (!_mouseCaptured && (x <= 0 || y <= 0))
             {
                 return;
             }