From 54b2b93722c9f067199cd7145dfd065d5b6b2f0c Mon Sep 17 00:00:00 2001
From: Behdad Esfahbod <behdad@behdad.org>
Date: Fri, 5 Jan 2018 13:20:21 +0000
Subject: [PATCH] [ot] Fix VariationStore evaluation algorithm

Ouch!  Missing coords should still be evaluated as coord=0, which
most of the time results in a factor of 0.  We were skipping these,
which was equivalent to a factor of 1.

Fixes https://github.com/harfbuzz/harfbuzz/issues/652
---
 src/hb-ot-layout-common-private.hh | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/src/hb-ot-layout-common-private.hh b/src/hb-ot-layout-common-private.hh
index 78e65d389..cb308cd2c 100644
--- a/src/hb-ot-layout-common-private.hh
+++ b/src/hb-ot-layout-common-private.hh
@@ -1275,10 +1275,11 @@ struct VarRegionList
     const VarRegionAxis *axes = axesZ + (region_index * axisCount);
 
     float v = 1.;
-    unsigned int count = MIN (coord_len, (unsigned int) axisCount);
+    unsigned int count = axisCount;
     for (unsigned int i = 0; i < count; i++)
     {
-      float factor = axes[i].evaluate (coords[i]);
+      int coord = i < coord_len ? coords[i] : 0;
+      float factor = axes[i].evaluate (coord);
       if (factor == 0.)
         return 0.;
       v *= factor;