From 963ac2258889ae56e436f29dea2b920e7ae9952f Mon Sep 17 00:00:00 2001
From: Dane Springmeyer <dane@mapbox.com>
Date: Tue, 21 Oct 2014 13:01:14 -0700
Subject: [PATCH] silence -Wunused-parameter warning in grain-extract for now -
 refs #2067

---
 deps/agg/include/agg_pixfmt_rgba.h | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/deps/agg/include/agg_pixfmt_rgba.h b/deps/agg/include/agg_pixfmt_rgba.h
index 9d5535128..40ddf6a07 100644
--- a/deps/agg/include/agg_pixfmt_rgba.h
+++ b/deps/agg/include/agg_pixfmt_rgba.h
@@ -1445,6 +1445,7 @@ struct comp_op_rgba_grain_merge
 
 // grain extract (GIMP)
 // E = I - M + 128
+// FIXME: https://github.com/mapnik/mapnik/issues/2067
 template <typename ColorT, typename Order>
 struct comp_op_rgba_grain_extract
 {
@@ -1461,7 +1462,7 @@ struct comp_op_rgba_grain_extract
 
     static AGG_INLINE void blend_pix(value_type* p,
                                      unsigned sr, unsigned sg, unsigned sb,
-                                     unsigned sa, unsigned cover)
+                                     unsigned sa, unsigned /*cover*/)
     {
         calc_type da = (p[Order::A] * sa + 255) >> 8;