From e8c47724638c29d78001905610c662de99c59cad Mon Sep 17 00:00:00 2001
From: Behdad Esfahbod <behdad@behdad.org>
Date: Tue, 6 Nov 2018 17:16:04 -0500
Subject: [PATCH] [kern] XXX Negate CrossKerning sign

Not sure why, but seems to better match GeezaPro Arabic w CoreText.

Quite possibly I'm doing something very wrong...
---
 src/hb-ot-kern-table.hh | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/hb-ot-kern-table.hh b/src/hb-ot-kern-table.hh
index 30f7091be..c7282a3a0 100644
--- a/src/hb-ot-kern-table.hh
+++ b/src/hb-ot-kern-table.hh
@@ -282,7 +282,8 @@ struct KernSubTableFormat1
 	    {
 	      if (crossStream)
 	      {
-	        crossOffset += v;
+	        /* XXX Why negative, not positive?!?! */
+	        crossOffset -= v;
 		buffer->pos[idx].y_offset += c->font->em_scale_y (crossOffset);
 	      }
 	      else