[freetype2-demos] master c4a0ccd: [graph] Small improvements.

[Alexei Podtelezhnikov]

branch: master
commit c4a0ccd9aa11459d183ddfa23dcae6d23144086d
Author: Alexei Podtelezhnikov <address@hidden>
Commit: Alexei Podtelezhnikov <address@hidden>

    [graph] Small improvements.
    
    * graph/gblender.h (GBLENDER_SHADE_INDEX): Round to nearest grid.
    * graph/gblender.c (gblender_lookup, gblender_lookup_channel): Minor.
---
 ChangeLog        |    7 +++++++
 graph/gblender.c |    4 ++--
 graph/gblender.h |    2 +-
 3 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 1e4399e..be88048 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+2015-12-06  Alexei Podtelezhnikov  <address@hidden>
+
+       [graph] Small improvements.
+
+       * graph/gblender.h (GBLENDER_SHADE_INDEX): Round to nearest grid.
+       * graph/gblender.c (gblender_lookup, gblender_lookup_channel): Minor.
+
 2015-12-05  Alexei Podtelezhnikov  <address@hidden>
 
        [graph] Unravel blending, part 2.
diff --git a/graph/gblender.c b/graph/gblender.c
index 2ea27fd..0a368f5 100644
--- a/graph/gblender.c
+++ b/graph/gblender.c
@@ -257,7 +257,7 @@ gblender_lookup( GBlender       blender,
   }
 #endif
 
-  idx0 = ( background + foreground*63 ) % GBLENDER_KEY_COUNT;
+  idx0 = ( background + foreground*63 ) & (GBLENDER_KEY_COUNT-1);
   idx  = idx0;
   do
   {
@@ -360,7 +360,7 @@ gblender_lookup_channel( GBlender      blender,
   }
 #endif
 
-  idx0 = ( background + foreground*17 ) % (GBLENDER_KEY_COUNT);
+  idx0 = ( background + foreground*17 ) & (GBLENDER_KEY_COUNT-1);
   idx  = idx0;
   do
   {
diff --git a/graph/gblender.h b/graph/gblender.h
index d1b092a..2adc9ba 100644
--- a/graph/gblender.h
+++ b/graph/gblender.h
@@ -19,7 +19,7 @@
 
 #define  GBLENDER_SHADE_BITS      4   /* must be <= 7 !! */
 #define  GBLENDER_SHADE_COUNT     ( 1 << GBLENDER_SHADE_BITS )
-#define  GBLENDER_SHADE_INDEX(n)  ((n) >> (8-GBLENDER_SHADE_BITS))
+#define  GBLENDER_SHADE_INDEX(n)  (((n) * (GBLENDER_SHADE_COUNT-1) + 128) >> 8)
 #define  GBLENDER_KEY_COUNT       256  /* must be a power of 2 */
 #define  GBLENDER_GAMMA_SHIFT     2