[freetype2-demos] master 3b031dd: [ftstring] Improve gamma ramp appearance.

[Alexei Podtelezhnikov]

branch: master
commit 3b031dd9b6309b0a1cdb5ad3b75dc9a888a11ee4
Author: Alexei Podtelezhnikov <address@hidden>
Commit: Alexei Podtelezhnikov <address@hidden>

    [ftstring] Improve gamma ramp appearance.
    
    * src/ftstring.c (event_gamma_change, gamma_ramp_draw): Updated.
---
 ChangeLog      |    6 ++++++
 src/ftstring.c |    7 ++-----
 2 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 975dfa9..0859393 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2017-01-28  Alexei Podtelezhnikov  <address@hidden>
+
+       [ftstring] Improve gamma ramp appearance.
+
+       * src/ftstring.c (event_gamma_change, gamma_ramp_draw): Updated.
+
 2017-01-28  Werner Lemberg  <address@hidden>
 
        [ftdump] Always finalize FreeType.
diff --git a/src/ftstring.c b/src/ftstring.c
index 45cb180..7f026d6 100644
--- a/src/ftstring.c
+++ b/src/ftstring.c
@@ -309,7 +309,6 @@
   event_gamma_change( double  delta )
   {
     int     i;
-    double  gamma_inv;
 
 
     status.gamma += delta;
@@ -321,10 +320,8 @@
 
     grSetGlyphGamma( status.gamma );
 
-    gamma_inv = 1. / status.gamma;
-
     for ( i = 0; i < 256; i++ )
-      status.gamma_ramp[i] = (FT_Byte)( pow( (double)i / 255., gamma_inv )
+      status.gamma_ramp[i] = (FT_Byte)( pow( (double)i / 255., status.gamma )
                                         * 255. + 0.5 );
   }
 
@@ -524,7 +521,7 @@
     y = ( bitmap->rows + 256 ) / 2;
 
     for (i = 0; i < 256; i++)
-      p[bitmap->pitch * ( y - gamma_ramp[i] ) + bpp * ( x + i )] ^= 0xFF;
+      p[bitmap->pitch * ( y - i ) + bpp * ( x + gamma_ramp[i] )] ^= 0xFF;
   }