shithub: freetype+ttf2subf

Download patch

ref: ebfd7ce52f6b3c81d522b03f8faf029b7ffb7cbc
parent: 44324b3746461f186e6b3c0e744b0fd823705ba3
author: Werner Lemberg <[email protected]>
date: Fri Feb 26 03:10:41 EST 2016 

[autofit] Improve BOUND action.

In complex glyph shapes, the original logic was too simple to cater
for situations that would actually need something similar to PS Hint
masks.  This fix should alleviate the worst cases.

* src/autofit/aflatin.c (af_latin_hint_edges): Don't allow
complete disappearance of stems.

git/fs: mount .git/fs: mount/attach disallowed 
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,14 @@
+2016-02-26  Werner Lemberg  <[email protected]>
+
+	[autofit] Improve BOUND action.
+
+	In complex glyph shapes, the original logic was too simple to cater
+	for situations that would actually need something similar to PS Hint
+	masks.  This fix should alleviate the worst cases.
+
+	* src/autofit/aflatin.c (af_latin_hint_edges): Don't allow
+	complete disappearance of stems.
+
 2016-02-25  Werner Lemberg  <[email protected]>
 
 	[autofit] Add blue-zone support for Tamil script.
--- a/src/autofit/aflatin.c
+++ b/src/autofit/aflatin.c
@@ -2885,14 +2885,21 @@
              ( top_to_bottom_hinting ? ( edge->pos > edge[-1].pos )
                                      : ( edge->pos < edge[-1].pos ) ) )
         {
+          /* don't move if stem would (almost) disappear otherwise; */
+          /* the ad-hoc value 16 corresponds to 1/4px               */
+          if ( edge->link && FT_ABS( edge->link->pos - edge[-1].pos ) > 16 )
+          {
 #ifdef FT_DEBUG_LEVEL_TRACE
-          FT_TRACE5(( "  BOUND: edge %d (pos=%.2f) moved to %.2f\n",
-                      edge - edges, edge->pos / 64.0, edge[-1].pos / 64.0 ));
+            FT_TRACE5(( "  BOUND: edge %d (pos=%.2f) moved to %.2f\n",
+                        edge - edges,
+                        edge->pos / 64.0,
+                        edge[-1].pos / 64.0 ));
 
-          num_actions++;
+            num_actions++;
 #endif
 
-          edge->pos = edge[-1].pos;
+            edge->pos = edge[-1].pos;
+          }
         }
       }
     }
@@ -3048,13 +3055,20 @@
              ( top_to_bottom_hinting ? ( edge->pos > edge[-1].pos )
                                      : ( edge->pos < edge[-1].pos ) ) )
         {
+          /* don't move if stem would (almost) disappear otherwise; */
+          /* the ad-hoc value 16 corresponds to 1/4px               */
+          if ( edge->link && FT_ABS( edge->link->pos - edge[-1].pos ) > 16 )
+          {
 #ifdef FT_DEBUG_LEVEL_TRACE
-          FT_TRACE5(( "  BOUND: edge %d (pos=%.2f) moved to %.2f\n",
-                      edge - edges, edge->pos / 64.0, edge[-1].pos / 64.0 ));
+            FT_TRACE5(( "  BOUND: edge %d (pos=%.2f) moved to %.2f\n",
+                        edge - edges,
+                        edge->pos / 64.0,
+                        edge[-1].pos / 64.0 ));
 
-          num_actions++;
+            num_actions++;
 #endif
-          edge->pos = edge[-1].pos;
+            edge->pos = edge[-1].pos;
+          }
         }
 
         if ( edge + 1 < edge_limit                                   &&
@@ -3062,14 +3076,21 @@
              ( top_to_bottom_hinting ? ( edge->pos < edge[1].pos )
                                      : ( edge->pos > edge[1].pos ) ) )
         {
+          /* don't move if stem would (almost) disappear otherwise; */
+          /* the ad-hoc value 16 corresponds to 1/4px               */
+          if ( edge->link && FT_ABS( edge->link->pos - edge[-1].pos ) > 16 )
+          {
 #ifdef FT_DEBUG_LEVEL_TRACE
-          FT_TRACE5(( "  BOUND: edge %d (pos=%.2f) moved to %.2f\n",
-                      edge - edges, edge->pos / 64.0, edge[1].pos / 64.0 ));
+            FT_TRACE5(( "  BOUND: edge %d (pos=%.2f) moved to %.2f\n",
+                        edge - edges,
+                        edge->pos / 64.0,
+                        edge[1].pos / 64.0 ));
 
-          num_actions++;
+            num_actions++;
 #endif
 
-          edge->pos = edge[1].pos;
+            edge->pos = edge[1].pos;
+          }
         }
       }
     }