Update bundled freetype to 2.6.1

third_party/freetype/src/truetype/ttgxvar.c

 /***************************************************************************/
 /*                                                                         */
 /*  ttgxvar.c                                                              */
 /*                                                                         */
 /*    TrueType GX Font Variation loader                                    */
 /*                                                                         */
-/*  Copyright 2004-2014 by                                                 */
+/*  Copyright 2004-2015 by                                                 */
 /*  David Turner, Robert Wilhelm, Werner Lemberg, and George Williams.     */
 /*                                                                         */
 /*  This file is part of the FreeType project, and may only be used,       */
 /*  modified, and distributed under the terms of the FreeType project      */
 /*  license, LICENSE.TXT.  By continuing to use, modify, or distribute     */
 /*  this file you indicate that you have read the license and              */
 /*  understand and accept it fully.                                        */
 /*                                                                         */
 /***************************************************************************/
 
 
   /*************************************************************************/
   /*                                                                       */
   /* Apple documents the `fvar', `gvar', `cvar', and `avar' tables at      */
   /*                                                                       */
-  /*   http://developer.apple.com/fonts/TTRefMan/RM06/Chap6[fgca]var.html  */
+  /*   https://developer.apple.com/fonts/TrueType-Reference-Manual/RM06/Chap6[fgca]var.html */
   /*                                                                       */
   /* The documentation for `fvar' is inconsistent.  At one point it says   */
   /* that `countSizePairs' should be 3, at another point 2.  It should     */
   /* be 2.                                                                 */
   /*                                                                       */
   /* The documentation for `gvar' is not intelligible; `cvar' refers you   */
   /* to `gvar' and is thus also incomprehensible.                          */
   /*                                                                       */
   /* The documentation for `avar' appears correct, but Apple has no fonts  */
   /* with an `avar' table, so it is hard to test.                          */
@@ skipping 19 matching lines @@
 
 #include "ttpload.h"
 #include "ttgxvar.h"
 
 #include "tterrors.h"
 
 
 #ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT
 
 
-#define FT_Stream_FTell( stream )  \
+#define FT_Stream_FTell( stream )                         \
           (FT_ULong)( (stream)->cursor - (stream)->base )
-#define FT_Stream_SeekSet( stream, off ) \
+#define FT_Stream_SeekSet( stream, off )                  \
           ( (stream)->cursor = (stream)->base + (off) )
 
 
   /*************************************************************************/
   /*                                                                       */
   /* The macro FT_COMPONENT is used in trace mode.  It is an implicit      */
   /* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log  */
   /* messages during execution.                                            */
   /*                                                                       */
 #undef  FT_COMPONENT
@@ skipping 13 matching lines @@
   /*                                                                       */
   /* The macro ALL_POINTS is used in `ft_var_readpackedpoints'.  It        */
   /* indicates that there is a delta for every point without needing to    */
   /* enumerate all of them.                                                */
   /*                                                                       */
 
   /* ensure that value `0' has the same width as a pointer */
 #define ALL_POINTS  (FT_UShort*)~(FT_PtrDist)0
 
 
-#define GX_PT_POINTS_ARE_WORDS      0x80
-#define GX_PT_POINT_RUN_COUNT_MASK  0x7F
+#define GX_PT_POINTS_ARE_WORDS      0x80U
+#define GX_PT_POINT_RUN_COUNT_MASK  0x7FU
 
 
   /*************************************************************************/
   /*                                                                       */
   /* <Function>                                                            */
   /*    ft_var_readpackedpoints                                            */
   /*                                                                       */
   /* <Description>                                                         */
   /*    Read a set of points to which the following deltas will apply.     */
   /*    Points are packed with a run length encoding.                      */
   /*                                                                       */
   /* <Input>                                                               */
   /*    stream    :: The data stream.                                      */
   /*                                                                       */
   /* <Output>                                                              */
   /*    point_cnt :: The number of points read.  A zero value means that   */
   /*                 all points in the glyph will be affected, without     */
   /*                 enumerating them individually.                        */
   /*                                                                       */
   /* <Return>                                                              */
   /*    An array of FT_UShort containing the affected points or the        */
   /*    special value ALL_POINTS.                                          */
   /*                                                                       */
   static FT_UShort*
   ft_var_readpackedpoints( FT_Stream  stream,
                            FT_UInt   *point_cnt )
   {
     FT_UShort *points = NULL;
-    FT_Int     n;
-    FT_Int     runcnt;
-    FT_Int     i;
-    FT_Int     j;
-    FT_Int     first;
+    FT_UInt    n;
+    FT_UInt    runcnt;
+    FT_UInt    i, j;
+    FT_UShort  first;
     FT_Memory  memory = stream->memory;
     FT_Error   error  = FT_Err_Ok;
 
     FT_UNUSED( error );
 
 
-    *point_cnt = n = FT_GET_BYTE();
+    *point_cnt = 0;
+
+    n = FT_GET_BYTE();
     if ( n == 0 )
       return ALL_POINTS;
 
     if ( n & GX_PT_POINTS_ARE_WORDS )
-      n = FT_GET_BYTE() | ( ( n & GX_PT_POINT_RUN_COUNT_MASK ) << 8 );
+    {
+      n  &= GX_PT_POINT_RUN_COUNT_MASK;
+      n <<= 8;
+      n  |= FT_GET_BYTE();
+    }
 
     if ( FT_NEW_ARRAY( points, n ) )
       return NULL;
 
+    *point_cnt = n;
+
     i = 0;
     while ( i < n )
     {
       runcnt = FT_GET_BYTE();
       if ( runcnt & GX_PT_POINTS_ARE_WORDS )
       {
-        runcnt = runcnt & GX_PT_POINT_RUN_COUNT_MASK;
-        first  = points[i++] = FT_GET_USHORT();
+        runcnt     &= GX_PT_POINT_RUN_COUNT_MASK;
+        first       = FT_GET_USHORT();
+        points[i++] = first;
 
-        if ( runcnt < 1 || i + runcnt >= n )
+        if ( runcnt < 1 || i + runcnt > n )
           goto Exit;
 
-        /* first point not included in runcount */
-        for ( j = 0; j < runcnt; ++j )
-          points[i++] = (FT_UShort)( first += FT_GET_USHORT() );
+        /* first point not included in run count */
+        for ( j = 0; j < runcnt; j++ )
+        {
+          first      += FT_GET_USHORT();
+          points[i++] = first;
+        }
       }
       else
       {
-        first = points[i++] = FT_GET_BYTE();
+        first       = FT_GET_BYTE();
+        points[i++] = first;
 
-        if ( runcnt < 1 || i + runcnt >= n )
+        if ( runcnt < 1 || i + runcnt > n )
           goto Exit;
 
-        for ( j = 0; j < runcnt; ++j )
-          points[i++] = (FT_UShort)( first += FT_GET_BYTE() );
+        for ( j = 0; j < runcnt; j++ )
+        {
+          first      += FT_GET_BYTE();
+          points[i++] = first;
+        }
       }
     }
 
   Exit:
     return points;
   }
 
 
-  enum
-  {
-    GX_DT_DELTAS_ARE_ZERO      = 0x80,
-    GX_DT_DELTAS_ARE_WORDS     = 0x40,
-    GX_DT_DELTA_RUN_COUNT_MASK = 0x3F
-  };
+#define GX_DT_DELTAS_ARE_ZERO       0x80U
+#define GX_DT_DELTAS_ARE_WORDS      0x40U
+#define GX_DT_DELTA_RUN_COUNT_MASK  0x3FU
 
 
   /*************************************************************************/
   /*                                                                       */
   /* <Function>                                                            */
   /*    ft_var_readpackeddeltas                                            */
   /*                                                                       */
   /* <Description>                                                         */
   /*    Read a set of deltas.  These are packed slightly differently than  */
   /*    points.  In particular there is no overall count.                  */
   /*                                                                       */
   /* <Input>                                                               */
   /*    stream    :: The data stream.                                      */
   /*                                                                       */
-  /*    delta_cnt :: The number of to be read.                             */
+  /*    delta_cnt :: The number of deltas to be read.                      */
   /*                                                                       */
   /* <Return>                                                              */
   /*    An array of FT_Short containing the deltas for the affected        */
   /*    points.  (This only gets the deltas for one dimension.  It will    */
   /*    generally be called twice, once for x, once for y.  When used in   */
   /*    cvt table, it will only be called once.)                           */
   /*                                                                       */
   static FT_Short*
   ft_var_readpackeddeltas( FT_Stream  stream,
-                           FT_Offset  delta_cnt )
+                           FT_UInt    delta_cnt )
   {
     FT_Short  *deltas = NULL;
-    FT_UInt    runcnt;
-    FT_Offset  i;
-    FT_UInt    j;
+    FT_UInt    runcnt, cnt;
+    FT_UInt    i, j;
     FT_Memory  memory = stream->memory;
     FT_Error   error  = FT_Err_Ok;
 
     FT_UNUSED( error );
 
 
     if ( FT_NEW_ARRAY( deltas, delta_cnt ) )
       return NULL;
 
     i = 0;
     while ( i < delta_cnt )
     {
       runcnt = FT_GET_BYTE();
+      cnt    = runcnt & GX_DT_DELTA_RUN_COUNT_MASK;
+
       if ( runcnt & GX_DT_DELTAS_ARE_ZERO )
       {
-        /* runcnt zeroes get added */
-        for ( j = 0;
-              j <= ( runcnt & GX_DT_DELTA_RUN_COUNT_MASK ) && i < delta_cnt;
-              ++j )
+        /* `runcnt' zeroes get added */
+        for ( j = 0; j <= cnt && i < delta_cnt; j++ )
           deltas[i++] = 0;
       }
       else if ( runcnt & GX_DT_DELTAS_ARE_WORDS )
       {
-        /* runcnt shorts from the stack */
-        for ( j = 0;
-              j <= ( runcnt & GX_DT_DELTA_RUN_COUNT_MASK ) && i < delta_cnt;
-              ++j )
+        /* `runcnt' shorts from the stack */
+        for ( j = 0; j <= cnt && i < delta_cnt; j++ )
           deltas[i++] = FT_GET_SHORT();
       }
       else
       {
-        /* runcnt signed bytes from the stack */
-        for ( j = 0;
-              j <= ( runcnt & GX_DT_DELTA_RUN_COUNT_MASK ) && i < delta_cnt;
-              ++j )
+        /* `runcnt' signed bytes from the stack */
+        for ( j = 0; j <= cnt && i < delta_cnt; j++ )
           deltas[i++] = FT_GET_CHAR();
       }
 
-      if ( j <= ( runcnt & GX_DT_DELTA_RUN_COUNT_MASK ) )
+      if ( j <= cnt )
       {
-        /* Bad format */
+        /* bad format */
         FT_FREE( deltas );
         return NULL;
       }
     }
 
     return deltas;
   }
 
 
   /*************************************************************************/
   /*                                                                       */
   /* <Function>                                                            */
   /*    ft_var_load_avar                                                   */
   /*                                                                       */
   /* <Description>                                                         */
   /*    Parse the `avar' table if present.  It need not be, so we return   */
   /*    nothing.                                                           */
   /*                                                                       */
   /* <InOut>                                                               */
   /*    face :: The font face.                                             */
   /*                                                                       */
   static void
   ft_var_load_avar( TT_Face  face )
   {
-    FT_Stream       stream = FT_FACE_STREAM(face);
+    FT_Stream       stream = FT_FACE_STREAM( face );
     FT_Memory       memory = stream->memory;
     GX_Blend        blend  = face->blend;
     GX_AVarSegment  segment;
     FT_Error        error = FT_Err_Ok;
-    FT_ULong        version;
+    FT_Long         version;
     FT_Long         axisCount;
     FT_Int          i, j;
     FT_ULong        table_len;
 
     FT_UNUSED( error );
 
 
+    FT_TRACE2(( "AVAR " ));
+
     blend->avar_checked = TRUE;
-    if ( (error = face->goto_table( face, TTAG_avar, stream, &table_len )) != 0 )
+    error = face->goto_table( face, TTAG_avar, stream, &table_len );
+    if ( error )
+    {
+      FT_TRACE2(( "is missing\n" ));
       return;
+    }
 
     if ( FT_FRAME_ENTER( table_len ) )
       return;
 
     version   = FT_GET_LONG();
     axisCount = FT_GET_LONG();
 
-    if ( version != 0x00010000L                       ||
-         axisCount != (FT_Long)blend->mmvar->num_axis )
+    if ( version != 0x00010000L )
+    {
+      FT_TRACE2(( "bad table version\n" ));
       goto Exit;
+    }
+
+    FT_TRACE2(( "loaded\n" ));
+
+    if ( axisCount != (FT_Long)blend->mmvar->num_axis )
+    {
+      FT_TRACE2(( "ft_var_load_avar: number of axes in `avar' and `cvar'\n"
+                  "                  table are different\n" ));
+      goto Exit;
+    }
 
     if ( FT_NEW_ARRAY( blend->avar_segment, axisCount ) )
       goto Exit;
 
     segment = &blend->avar_segment[0];
-    for ( i = 0; i < axisCount; ++i, ++segment )
+    for ( i = 0; i < axisCount; i++, segment++ )
     {
+      FT_TRACE5(( "  axis %d:\n", i ));
+
       segment->pairCount = FT_GET_USHORT();
       if ( FT_NEW_ARRAY( segment->correspondence, segment->pairCount ) )
       {
         /* Failure.  Free everything we have done so far.  We must do */
         /* it right now since loading the `avar' table is optional.   */
 
-        for ( j = i - 1; j >= 0; --j )
+        for ( j = i - 1; j >= 0; j-- )
           FT_FREE( blend->avar_segment[j].correspondence );
 
         FT_FREE( blend->avar_segment );
         blend->avar_segment = NULL;
         goto Exit;
       }
 
-      for ( j = 0; j < segment->pairCount; ++j )
+      for ( j = 0; j < segment->pairCount; j++ )
       {
-        segment->correspondence[j].fromCoord =
-          FT_GET_SHORT() << 2;    /* convert to Fixed */
-        segment->correspondence[j].toCoord =
-          FT_GET_SHORT()<<2;    /* convert to Fixed */
+        /* convert to Fixed */
+        segment->correspondence[j].fromCoord = FT_GET_SHORT() * 4;
+        segment->correspondence[j].toCoord   = FT_GET_SHORT() * 4;
+
+        FT_TRACE5(( "    mapping %.4f to %.4f\n",
+                    segment->correspondence[j].fromCoord / 65536.0,
+                    segment->correspondence[j].toCoord / 65536.0 ));
       }
+
+      FT_TRACE5(( "\n" ));
     }
 
   Exit:
     FT_FRAME_EXIT();
   }
 
 
   typedef struct  GX_GVar_Head_
   {
     FT_Long    version;
     FT_UShort  axisCount;
     FT_UShort  globalCoordCount;
     FT_ULong   offsetToCoord;
     FT_UShort  glyphCount;
     FT_UShort  flags;
     FT_ULong   offsetToData;
 
   } GX_GVar_Head;
 
 
   /*************************************************************************/
   /*                                                                       */
   /* <Function>                                                            */
   /*    ft_var_load_gvar                                                   */
   /*                                                                       */
   /* <Description>                                                         */
-  /*    Parses the `gvar' table if present.  If `fvar' is there, `gvar'    */
-  /*    had better be there too.                                           */
+  /*    Parse the `gvar' table if present.  If `fvar' is there, `gvar' had */
+  /*    better be there too.                                               */
   /*                                                                       */
   /* <InOut>                                                               */
   /*    face :: The font face.                                             */
   /*                                                                       */
   /* <Return>                                                              */
   /*    FreeType error code.  0 means success.                             */
   /*                                                                       */
   static FT_Error
   ft_var_load_gvar( TT_Face  face )
   {
-    FT_Stream     stream = FT_FACE_STREAM(face);
+    FT_Stream     stream = FT_FACE_STREAM( face );
     FT_Memory     memory = stream->memory;
     GX_Blend      blend  = face->blend;
     FT_Error      error;
     FT_UInt       i, j;
     FT_ULong      table_len;
     FT_ULong      gvar_start;
     FT_ULong      offsetToData;
     GX_GVar_Head  gvar_head;
 
     static const FT_Frame_Field  gvar_fields[] =
     {
 
 #undef  FT_STRUCTURE
 #define FT_STRUCTURE  GX_GVar_Head
 
       FT_FRAME_START( 20 ),
         FT_FRAME_LONG  ( version ),
         FT_FRAME_USHORT( axisCount ),
         FT_FRAME_USHORT( globalCoordCount ),
         FT_FRAME_ULONG ( offsetToCoord ),
         FT_FRAME_USHORT( glyphCount ),
         FT_FRAME_USHORT( flags ),
         FT_FRAME_ULONG ( offsetToData ),
       FT_FRAME_END
     };
 
-    if ( (error = face->goto_table( face, TTAG_gvar, stream, &table_len )) != 0 )
+
+    FT_TRACE2(( "GVAR " ));
+
+    if ( ( error = face->goto_table( face,
+                                     TTAG_gvar,
+                                     stream,
+                                     &table_len ) ) != 0 )
+    {
+      FT_TRACE2(( "is missing\n" ));
       goto Exit;
+    }
 
     gvar_start = FT_STREAM_POS( );
     if ( FT_STREAM_READ_FIELDS( gvar_fields, &gvar_head ) )
       goto Exit;
 
     blend->tuplecount  = gvar_head.globalCoordCount;
     blend->gv_glyphcnt = gvar_head.glyphCount;
     offsetToData       = gvar_start + gvar_head.offsetToData;
 
-    if ( gvar_head.version   != (FT_Long)0x00010000L              ||
-         gvar_head.axisCount != (FT_UShort)blend->mmvar->num_axis )
+    if ( gvar_head.version != 0x00010000L )
     {
+      FT_TRACE1(( "bad table version\n" ));
       error = FT_THROW( Invalid_Table );
       goto Exit;
     }
 
+    FT_TRACE2(( "loaded\n" ));
+
+    if ( gvar_head.axisCount != (FT_UShort)blend->mmvar->num_axis )
+    {
+      FT_TRACE1(( "ft_var_load_gvar: number of axes in `gvar' and `cvar'\n"
+                  "                  table are different\n" ));
+      error = FT_THROW( Invalid_Table );
+      goto Exit;
+    }
+
+    FT_TRACE5(( "gvar: there are %d shared coordinates:\n",
+                blend->tuplecount ));
+
     if ( FT_NEW_ARRAY( blend->glyphoffsets, blend->gv_glyphcnt + 1 ) )
       goto Exit;
 
     if ( gvar_head.flags & 1 )
     {
       /* long offsets (one more offset than glyphs, to mark size of last) */
       if ( FT_FRAME_ENTER( ( blend->gv_glyphcnt + 1 ) * 4L ) )
         goto Exit;
 
-      for ( i = 0; i <= blend->gv_glyphcnt; ++i )
-        blend->glyphoffsets[i] = offsetToData + FT_GET_LONG();
+      for ( i = 0; i <= blend->gv_glyphcnt; i++ )
+        blend->glyphoffsets[i] = offsetToData + FT_GET_ULONG();
 
       FT_FRAME_EXIT();
     }
     else
     {
       /* short offsets (one more offset than glyphs, to mark size of last) */
       if ( FT_FRAME_ENTER( ( blend->gv_glyphcnt + 1 ) * 2L ) )
         goto Exit;
 
-      for ( i = 0; i <= blend->gv_glyphcnt; ++i )
+      for ( i = 0; i <= blend->gv_glyphcnt; i++ )
         blend->glyphoffsets[i] = offsetToData + FT_GET_USHORT() * 2;
-                                              /* XXX: Undocumented: `*2'! */
+                                               /* XXX: Undocumented: `*2'! */
 
       FT_FRAME_EXIT();
     }
 
     if ( blend->tuplecount != 0 )
     {
       if ( FT_NEW_ARRAY( blend->tuplecoords,
                          gvar_head.axisCount * blend->tuplecount ) )
         goto Exit;
 
-      if ( FT_STREAM_SEEK( gvar_start + gvar_head.offsetToCoord )       ||
-           FT_FRAME_ENTER( blend->tuplecount * gvar_head.axisCount * 2L )                   )
+      if ( FT_STREAM_SEEK( gvar_start + gvar_head.offsetToCoord )         ||
+           FT_FRAME_ENTER( blend->tuplecount * gvar_head.axisCount * 2L ) )
         goto Exit;
 
-      for ( i = 0; i < blend->tuplecount; ++i )
-        for ( j = 0 ; j < (FT_UInt)gvar_head.axisCount; ++j )
+      for ( i = 0; i < blend->tuplecount; i++ )
+      {
+        FT_TRACE5(( "  [ " ));
+        for ( j = 0 ; j < (FT_UInt)gvar_head.axisCount; j++ )
+        {
           blend->tuplecoords[i * gvar_head.axisCount + j] =
-            FT_GET_SHORT() << 2;                /* convert to FT_Fixed */
+            FT_GET_SHORT() * 4;                 /* convert to FT_Fixed */
+          FT_TRACE5(( "%.4f ",
+            blend->tuplecoords[i * gvar_head.axisCount + j] / 65536.0 ));
+        }
+        FT_TRACE5(( "]\n" ));
+      }
+
+      FT_TRACE5(( "\n" ));
 
       FT_FRAME_EXIT();
     }
 
   Exit:
     return error;
   }
 
 
   /*************************************************************************/
@@ skipping 27 matching lines @@
   ft_var_apply_tuple( GX_Blend   blend,
                       FT_UShort  tupleIndex,
                       FT_Fixed*  tuple_coords,
                       FT_Fixed*  im_start_coords,
                       FT_Fixed*  im_end_coords )
   {
     FT_UInt   i;
     FT_Fixed  apply = 0x10000L;
 
 
-    for ( i = 0; i < blend->num_axis; ++i )
+    for ( i = 0; i < blend->num_axis; i++ )
     {
+      FT_TRACE6(( "    axis coordinate %d (%.4f):\n",
+                  i, blend->normalizedcoords[i] / 65536.0 ));
+
+      /* It's not clear why (for intermediate tuples) we don't need     */
+      /* to check against start/end -- the documentation says we don't. */
+      /* Similarly, it's unclear why we don't need to scale along the   */
+      /* axis.                                                          */
+
       if ( tuple_coords[i] == 0 )
-        /* It's not clear why (for intermediate tuples) we don't need     */
-        /* to check against start/end -- the documentation says we don't. */
-        /* Similarly, it's unclear why we don't need to scale along the   */
-        /* axis.                                                          */
+      {
+        FT_TRACE6(( "      tuple coordinate is zero, ignored\n", i ));
         continue;
+      }
 
-      else if ( blend->normalizedcoords[i] == 0                           ||
-                ( blend->normalizedcoords[i] < 0 && tuple_coords[i] > 0 ) ||
+      else if ( blend->normalizedcoords[i] == 0 )
+      {
+        FT_TRACE6(( "      axis coordinate is zero, stop\n" ));
+        apply = 0;
+        break;
+      }
+
+      else if ( ( blend->normalizedcoords[i] < 0 && tuple_coords[i] > 0 ) ||
                 ( blend->normalizedcoords[i] > 0 && tuple_coords[i] < 0 ) )
       {
+        FT_TRACE6(( "      tuple coordinate value %.4f is exceeded, stop\n",
+                    tuple_coords[i] / 65536.0 ));
         apply = 0;
         break;
       }
 
       else if ( !( tupleIndex & GX_TI_INTERMEDIATE_TUPLE ) )
+      {
+        FT_TRACE6(( "      tuple coordinate value %.4f fits\n",
+                    tuple_coords[i] / 65536.0 ));
         /* not an intermediate tuple */
         apply = FT_MulFix( apply,
                            blend->normalizedcoords[i] > 0
                              ? blend->normalizedcoords[i]
                              : -blend->normalizedcoords[i] );
+      }
 
-      else if ( blend->normalizedcoords[i] <= im_start_coords[i] ||
-                blend->normalizedcoords[i] >= im_end_coords[i]   )
+      else if ( blend->normalizedcoords[i] < im_start_coords[i] ||
+                blend->normalizedcoords[i] > im_end_coords[i]   )
       {
+        FT_TRACE6(( "      intermediate tuple range [%.4f;%.4f] is exceeded,"
+                    " stop\n",
+                    im_start_coords[i] / 65536.0,
+                    im_end_coords[i] / 65536.0 ));
         apply = 0;
         break;
       }
 
       else if ( blend->normalizedcoords[i] < tuple_coords[i] )
+      {
+        FT_TRACE6(( "      intermediate tuple range [%.4f;%.4f] fits\n",
+                    im_start_coords[i] / 65536.0,
+                    im_end_coords[i] / 65536.0 ));
         apply = FT_MulDiv( apply,
                            blend->normalizedcoords[i] - im_start_coords[i],
                            tuple_coords[i] - im_start_coords[i] );
+      }
 
       else
+      {
+        FT_TRACE6(( "      intermediate tuple range [%.4f;%.4f] fits\n",
+                    im_start_coords[i] / 65536.0,
+                    im_end_coords[i] / 65536.0 ));
         apply = FT_MulDiv( apply,
                            im_end_coords[i] - blend->normalizedcoords[i],
                            im_end_coords[i] - tuple_coords[i] );
+      }
     }
 
+    FT_TRACE6(( "    apply factor is %.4f\n", apply / 65536.0 ));
+
     return apply;
   }
 
 
   /*************************************************************************/
   /*************************************************************************/
   /*****                                                               *****/
   /*****               MULTIPLE MASTERS SERVICE FUNCTIONS              *****/
   /*****                                                               *****/
   /*************************************************************************/
   /*************************************************************************/
 
 
   typedef struct  GX_FVar_Head_
   {
     FT_Long    version;
     FT_UShort  offsetToData;
     FT_UShort  countSizePairs;
     FT_UShort  axisCount;
     FT_UShort  axisSize;
     FT_UShort  instanceCount;
     FT_UShort  instanceSize;
 
   } GX_FVar_Head;
 
 
   typedef struct  fvar_axis_
   {
     FT_ULong   axisTag;
-    FT_ULong   minValue;
-    FT_ULong   defaultValue;
-    FT_ULong   maxValue;
+    FT_Fixed   minValue;
+    FT_Fixed   defaultValue;
+    FT_Fixed   maxValue;
     FT_UShort  flags;
     FT_UShort  nameID;
 
   } GX_FVar_Axis;
 
 
   /*************************************************************************/
   /*                                                                       */
   /* <Function>                                                            */
   /*    TT_Get_MM_Var                                                      */
   /*                                                                       */
   /* <Description>                                                         */
   /*    Check that the font's `fvar' table is valid, parse it, and return  */
   /*    those data.                                                        */
   /*                                                                       */
   /* <InOut>                                                               */
   /*    face   :: The font face.                                           */
   /*              TT_Get_MM_Var initializes the blend structure.           */
   /*                                                                       */
   /* <Output>                                                              */
-  /*    master :: The `fvar' data (must be freed by caller).               */
+  /*    master :: The `fvar' data (must be freed by caller).  Can be NULL, */
+  /*              which makes this function simply load MM support.        */
   /*                                                                       */
   /* <Return>                                                              */
   /*    FreeType error code.  0 means success.                             */
   /*                                                                       */
   FT_LOCAL_DEF( FT_Error )
   TT_Get_MM_Var( TT_Face      face,
                  FT_MM_Var*  *master )
   {
     FT_Stream            stream = face->root.stream;
     FT_Memory            memory = face->root.memory;
@@ skipping 26 matching lines @@
     };
 
     static const FT_Frame_Field  fvaraxis_fields[] =
     {
 
 #undef  FT_STRUCTURE
 #define FT_STRUCTURE  GX_FVar_Axis
 
       FT_FRAME_START( 20 ),
         FT_FRAME_ULONG ( axisTag ),
-        FT_FRAME_ULONG ( minValue ),
-        FT_FRAME_ULONG ( defaultValue ),
-        FT_FRAME_ULONG ( maxValue ),
+        FT_FRAME_LONG  ( minValue ),
+        FT_FRAME_LONG  ( defaultValue ),
+        FT_FRAME_LONG  ( maxValue ),
         FT_FRAME_USHORT( flags ),
         FT_FRAME_USHORT( nameID ),
       FT_FRAME_END
     };
 
 
+    /* read the font data and set up the internal representation */
+    /* if not already done                                       */
+
     if ( face->blend == NULL )
     {
+      FT_TRACE2(( "FVAR " ));
+
       /* both `fvar' and `gvar' must be present */
-      if ( (error = face->goto_table( face, TTAG_gvar,
-                                      stream, &table_len )) != 0 )
+      if ( ( error = face->goto_table( face, TTAG_gvar,
+                                       stream, &table_len ) ) != 0 )
+      {
+        FT_TRACE1(( "\n"
+                    "TT_Get_MM_Var: `gvar' table is missing\n" ));
         goto Exit;
+      }
 
-      if ( (error = face->goto_table( face, TTAG_fvar,
-                                      stream, &table_len )) != 0 )
+      if ( ( error = face->goto_table( face, TTAG_fvar,
+                                       stream, &table_len ) ) != 0 )
+      {
+        FT_TRACE1(( "is missing\n" ));
         goto Exit;
+      }
 
       fvar_start = FT_STREAM_POS( );
 
       if ( FT_STREAM_READ_FIELDS( fvar_fields, &fvar_head ) )
         goto Exit;
 
       if ( fvar_head.version != (FT_Long)0x00010000L                      ||
+#if 0
+           /* fonts like `JamRegular.ttf' have an incorrect value for */
+           /* `countSizePairs'; since value 2 is hard-coded in `fvar' */
+           /* version 1.0, we simply ignore it                        */
            fvar_head.countSizePairs != 2                                  ||
+#endif
            fvar_head.axisSize != 20                                       ||
            /* axisCount limit implied by 16-bit instanceSize */
            fvar_head.axisCount > 0x3FFE                                   ||
            fvar_head.instanceSize != 4 + 4 * fvar_head.axisCount          ||
            /* instanceCount limit implied by limited range of name IDs */
            fvar_head.instanceCount > 0x7EFF                               ||
            fvar_head.offsetToData + fvar_head.axisCount * 20U +
              fvar_head.instanceCount * fvar_head.instanceSize > table_len )
       {
+        FT_TRACE1(( "\n"
+                    "TT_Get_MM_Var: invalid `fvar' header\n" ));
         error = FT_THROW( Invalid_Table );
         goto Exit;
       }
 
+      FT_TRACE2(( "loaded\n" ));
+
+      FT_TRACE5(( "number of GX style axes: %d\n", fvar_head.axisCount ));
+
       if ( FT_NEW( face->blend ) )
         goto Exit;
 
       /* cannot overflow 32-bit arithmetic because of limits above */
       face->blend->mmvar_len =
         sizeof ( FT_MM_Var ) +
         fvar_head.axisCount * sizeof ( FT_Var_Axis ) +
         fvar_head.instanceCount * sizeof ( FT_Var_Named_Style ) +
         fvar_head.instanceCount * fvar_head.axisCount * sizeof ( FT_Fixed ) +
         5 * fvar_head.axisCount;
 
       if ( FT_ALLOC( mmvar, face->blend->mmvar_len ) )
         goto Exit;
       face->blend->mmvar = mmvar;
 
+      /* set up pointers and offsets into the `mmvar' array; */
+      /* the data gets filled in later on                    */
+
       mmvar->num_axis =
         fvar_head.axisCount;
       mmvar->num_designs =
         ~0U;                   /* meaningless in this context; each glyph */
                                /* may have a different number of designs  */
                                /* (or tuples, as called by Apple)         */
       mmvar->num_namedstyles =
         fvar_head.instanceCount;
       mmvar->axis =
-        (FT_Var_Axis*)&(mmvar[1]);
+        (FT_Var_Axis*)&( mmvar[1] );
       mmvar->namedstyle =
-        (FT_Var_Named_Style*)&(mmvar->axis[fvar_head.axisCount]);
+        (FT_Var_Named_Style*)&( mmvar->axis[fvar_head.axisCount] );
 
       next_coords =
-        (FT_Fixed*)&(mmvar->namedstyle[fvar_head.instanceCount]);
-      for ( i = 0; i < fvar_head.instanceCount; ++i )
+        (FT_Fixed*)&( mmvar->namedstyle[fvar_head.instanceCount] );
+      for ( i = 0; i < fvar_head.instanceCount; i++ )
       {
         mmvar->namedstyle[i].coords  = next_coords;
         next_coords                 += fvar_head.axisCount;
       }
 
       next_name = (FT_String*)next_coords;
-      for ( i = 0; i < fvar_head.axisCount; ++i )
+      for ( i = 0; i < fvar_head.axisCount; i++ )
       {
         mmvar->axis[i].name  = next_name;
         next_name           += 5;
       }
 
+      /* now fill in the data */
+
       if ( FT_STREAM_SEEK( fvar_start + fvar_head.offsetToData ) )
         goto Exit;
 
       a = mmvar->axis;
-      for ( i = 0; i < fvar_head.axisCount; ++i )
+      for ( i = 0; i < fvar_head.axisCount; i++ )
       {
         GX_FVar_Axis  axis_rec;
 
 
         if ( FT_STREAM_READ_FIELDS( fvaraxis_fields, &axis_rec ) )
           goto Exit;
         a->tag     = axis_rec.axisTag;
-        a->minimum = axis_rec.minValue;     /* A Fixed */
-        a->def     = axis_rec.defaultValue; /* A Fixed */
-        a->maximum = axis_rec.maxValue;     /* A Fixed */
+        a->minimum = axis_rec.minValue;
+        a->def     = axis_rec.defaultValue;
+        a->maximum = axis_rec.maxValue;
         a->strid   = axis_rec.nameID;
 
         a->name[0] = (FT_String)(   a->tag >> 24 );
         a->name[1] = (FT_String)( ( a->tag >> 16 ) & 0xFF );
         a->name[2] = (FT_String)( ( a->tag >>  8 ) & 0xFF );
         a->name[3] = (FT_String)( ( a->tag       ) & 0xFF );
-        a->name[4] = 0;
+        a->name[4] = '\0';
 
-        ++a;
+        FT_TRACE5(( "  \"%s\": minimum=%.4f, default=%.4f, maximum=%.4f\n",
+                    a->name,
+                    a->minimum / 65536.0,
+                    a->def / 65536.0,
+                    a->maximum / 65536.0 ));
+
+        a++;
       }
 
+      FT_TRACE5(( "\n" ));
+
       ns = mmvar->namedstyle;
-      for ( i = 0; i < fvar_head.instanceCount; ++i, ++ns )
+      for ( i = 0; i < fvar_head.instanceCount; i++, ns++ )
       {
         if ( FT_FRAME_ENTER( 4L + 4L * fvar_head.axisCount ) )
           goto Exit;
 
         ns->strid       =    FT_GET_USHORT();
         (void) /* flags = */ FT_GET_USHORT();
 
-        for ( j = 0; j < fvar_head.axisCount; ++j )
-          ns->coords[j] = FT_GET_ULONG();     /* A Fixed */
+        for ( j = 0; j < fvar_head.axisCount; j++ )
+          ns->coords[j] = FT_GET_LONG();
 
         FT_FRAME_EXIT();
       }
     }
 
+    /* fill the output array if requested */
+
     if ( master != NULL )
     {
       FT_UInt  n;
 
 
       if ( FT_ALLOC( mmvar, face->blend->mmvar_len ) )
         goto Exit;
       FT_MEM_COPY( mmvar, face->blend->mmvar, face->blend->mmvar_len );
 
       mmvar->axis =
-        (FT_Var_Axis*)&(mmvar[1]);
+        (FT_Var_Axis*)&( mmvar[1] );
       mmvar->namedstyle =
-        (FT_Var_Named_Style*)&(mmvar->axis[mmvar->num_axis]);
+        (FT_Var_Named_Style*)&( mmvar->axis[mmvar->num_axis] );
       next_coords =
-        (FT_Fixed*)&(mmvar->namedstyle[mmvar->num_namedstyles]);
+        (FT_Fixed*)&( mmvar->namedstyle[mmvar->num_namedstyles] );
 
-      for ( n = 0; n < mmvar->num_namedstyles; ++n )
+      for ( n = 0; n < mmvar->num_namedstyles; n++ )
       {
         mmvar->namedstyle[n].coords  = next_coords;
         next_coords                 += mmvar->num_axis;
       }
 
-      a = mmvar->axis;
+      a         = mmvar->axis;
       next_name = (FT_String*)next_coords;
-      for ( n = 0; n < mmvar->num_axis; ++n )
+      for ( n = 0; n < mmvar->num_axis; n++ )
       {
         a->name = next_name;
 
         /* standard PostScript names for some standard apple tags */
         if ( a->tag == TTAG_wght )
-          a->name = (char *)"Weight";
+          a->name = (char*)"Weight";
         else if ( a->tag == TTAG_wdth )
-          a->name = (char *)"Width";
+          a->name = (char*)"Width";
         else if ( a->tag == TTAG_opsz )
-          a->name = (char *)"OpticalSize";
+          a->name = (char*)"OpticalSize";
         else if ( a->tag == TTAG_slnt )
-          a->name = (char *)"Slant";
+          a->name = (char*)"Slant";
 
         next_name += 5;
-        ++a;
+        a++;
       }
 
       *master = mmvar;
     }
 
   Exit:
     return error;
   }
 
 
   /*************************************************************************/
   /*                                                                       */
   /* <Function>                                                            */
   /*    TT_Set_MM_Blend                                                    */
   /*                                                                       */
   /* <Description>                                                         */
   /*    Set the blend (normalized) coordinates for this instance of the    */
   /*    font.  Check that the `gvar' table is reasonable and does some     */
   /*    initial preparation.                                               */
   /*                                                                       */
   /* <InOut>                                                               */
   /*    face       :: The font.                                            */
   /*                  Initialize the blend structure with `gvar' data.     */
   /*                                                                       */
   /* <Input>                                                               */
-  /*    num_coords :: Must be the axis count of the font.                  */
+  /*    num_coords :: The number of available coordinates.  If it is       */
+  /*                  larger than the number of axes, ignore the excess    */
+  /*                  values.  If it is smaller than the number of axes,   */
+  /*                  use the default value (0) for the remaining axes.    */
   /*                                                                       */
-  /*    coords     :: An array of num_coords, each between [-1,1].         */
+  /*    coords     :: An array of `num_coords', each between [-1,1].       */
   /*                                                                       */
   /* <Return>                                                              */
   /*    FreeType error code.  0 means success.                             */
   /*                                                                       */
   FT_LOCAL_DEF( FT_Error )
   TT_Set_MM_Blend( TT_Face    face,
                    FT_UInt    num_coords,
                    FT_Fixed*  coords )
   {
     FT_Error    error = FT_Err_Ok;
     GX_Blend    blend;
     FT_MM_Var*  mmvar;
     FT_UInt     i;
     FT_Memory   memory = face->root.memory;
 
     enum
     {
       mcvt_retain,
       mcvt_modify,
       mcvt_load
 
     } manageCvt;
 
 
     face->doblend = FALSE;
 
     if ( face->blend == NULL )
     {
-      if ( (error = TT_Get_MM_Var( face, NULL)) != 0 )
+      if ( ( error = TT_Get_MM_Var( face, NULL ) ) != 0 )
         goto Exit;
     }
 
     blend = face->blend;
     mmvar = blend->mmvar;
 
-    if ( num_coords != mmvar->num_axis )
+    if ( num_coords > mmvar->num_axis )
     {
-      error = FT_THROW( Invalid_Argument );
-      goto Exit;
+      FT_TRACE2(( "TT_Set_MM_Blend: only using first %d of %d coordinates\n",
+                  mmvar->num_axis, num_coords ));
+      num_coords = mmvar->num_axis;
     }
 
-    for ( i = 0; i < num_coords; ++i )
+    FT_TRACE5(( "normalized design coordinates:\n" ));
+
+    for ( i = 0; i < num_coords; i++ )
+    {
+      FT_TRACE5(( "  %.4f\n", coords[i] / 65536.0 ));
       if ( coords[i] < -0x00010000L || coords[i] > 0x00010000L )
       {
+        FT_TRACE1(( "TT_Set_MM_Blend: normalized design coordinate %.4f\n"
+                    "                 is out of range [-1;1]\n",
+                    coords[i] / 65536.0 ));
         error = FT_THROW( Invalid_Argument );
         goto Exit;
       }
+    }
+
+    FT_TRACE5(( "\n" ));
 
     if ( blend->glyphoffsets == NULL )
-      if ( (error = ft_var_load_gvar( face )) != 0 )
+      if ( ( error = ft_var_load_gvar( face ) ) != 0 )
         goto Exit;
 
     if ( blend->normalizedcoords == NULL )
     {
-      if ( FT_NEW_ARRAY( blend->normalizedcoords, num_coords ) )
+      if ( FT_NEW_ARRAY( blend->normalizedcoords, mmvar->num_axis ) )
         goto Exit;
 
       manageCvt = mcvt_modify;
 
       /* If we have not set the blend coordinates before this, then the  */
       /* cvt table will still be what we read from the `cvt ' table and  */
       /* we don't need to reload it.  We may need to change it though... */
     }
     else
     {
       manageCvt = mcvt_retain;
-      for ( i = 0; i < num_coords; ++i )
+
+      for ( i = 0; i < num_coords; i++ )
       {
         if ( blend->normalizedcoords[i] != coords[i] )
         {
           manageCvt = mcvt_load;
           break;
         }
       }
 
+      for ( ; i < mmvar->num_axis; i++ )
+      {
+        if ( blend->normalizedcoords[i] != 0 )
+        {
+          manageCvt = mcvt_load;
+          break;
+        }
+      }
+
       /* If we don't change the blend coords then we don't need to do  */
       /* anything to the cvt table.  It will be correct.  Otherwise we */
       /* no longer have the original cvt (it was modified when we set  */
       /* the blend last time), so we must reload and then modify it.   */
     }
 
-    blend->num_axis = num_coords;
+    blend->num_axis = mmvar->num_axis;
     FT_MEM_COPY( blend->normalizedcoords,
                  coords,
                  num_coords * sizeof ( FT_Fixed ) );
 
     face->doblend = TRUE;
 
     if ( face->cvt != NULL )
     {
       switch ( manageCvt )
       {
@@ skipping 31 matching lines @@
   /* <Description>                                                         */
   /*    Set the coordinates for the instance, measured in the user         */
   /*    coordinate system.  Parse the `avar' table (if present) to convert */
   /*    from user to normalized coordinates.                               */
   /*                                                                       */
   /* <InOut>                                                               */
   /*    face       :: The font face.                                       */
   /*                  Initialize the blend struct with `gvar' data.        */
   /*                                                                       */
   /* <Input>                                                               */
-  /*    num_coords :: This must be the axis count of the font.             */
+  /*    num_coords :: The number of available coordinates.  If it is       */
+  /*                  larger than the number of axes, ignore the excess    */
+  /*                  values.  If it is smaller than the number of axes,   */
+  /*                  use the default values for the remaining axes.       */
   /*                                                                       */
   /*    coords     :: A coordinate array with `num_coords' elements.       */
   /*                                                                       */
   /* <Return>                                                              */
   /*    FreeType error code.  0 means success.                             */
   /*                                                                       */
   FT_LOCAL_DEF( FT_Error )
   TT_Set_Var_Design( TT_Face    face,
                      FT_UInt    num_coords,
                      FT_Fixed*  coords )
   {
     FT_Error        error      = FT_Err_Ok;
     FT_Fixed*       normalized = NULL;
     GX_Blend        blend;
     FT_MM_Var*      mmvar;
     FT_UInt         i, j;
     FT_Var_Axis*    a;
     GX_AVarSegment  av;
     FT_Memory       memory = face->root.memory;
 
 
     if ( face->blend == NULL )
     {
-      if ( (error = TT_Get_MM_Var( face, NULL )) != 0 )
+      if ( ( error = TT_Get_MM_Var( face, NULL ) ) != 0 )
         goto Exit;
     }
 
     blend = face->blend;
     mmvar = blend->mmvar;
 
-    if ( num_coords != mmvar->num_axis )
+    if ( num_coords > mmvar->num_axis )
     {
-      error = FT_THROW( Invalid_Argument );
-      goto Exit;
+      FT_TRACE2(( "TT_Set_Var_Design:"
+                  " only using first %d of %d coordinates\n",
+                  mmvar->num_axis, num_coords ));
+      num_coords = mmvar->num_axis;
     }
 
     /* Axis normalization is a two stage process.  First we normalize */
     /* based on the [min,def,max] values for the axis to be [-1,0,1]. */
     /* Then, if there's an `avar' table, we renormalize this range.   */
 
     if ( FT_NEW_ARRAY( normalized, mmvar->num_axis ) )
       goto Exit;
 
+    FT_TRACE5(( "design coordinates:\n" ));
+
     a = mmvar->axis;
-    for ( i = 0; i < mmvar->num_axis; ++i, ++a )
+    for ( i = 0; i < num_coords; i++, a++ )
     {
+      FT_TRACE5(( "  %.4f\n", coords[i] / 65536.0 ));
       if ( coords[i] > a->maximum || coords[i] < a->minimum )
       {
+        FT_TRACE1(( "TT_Set_Var_Design: normalized design coordinate %.4f\n"
+                    "                   is out of range [%.4f;%.4f]\n",
+                    coords[i] / 65536.0,
+                    a->minimum / 65536.0,
+                    a->maximum / 65536.0 ));
         error = FT_THROW( Invalid_Argument );
         goto Exit;
       }
 
       if ( coords[i] < a->def )
-        normalized[i] = -FT_DivFix( coords[i] - a->def, a->minimum - a->def );
+        normalized[i] = -FT_DivFix( coords[i] - a->def,
+                                    a->minimum - a->def );
       else if ( a->maximum == a->def )
         normalized[i] = 0;
       else
-        normalized[i] = FT_DivFix( coords[i] - a->def, a->maximum - a->def );
+        normalized[i] = FT_DivFix( coords[i] - a->def,
+                                   a->maximum - a->def );
     }
 
+    FT_TRACE5(( "\n" ));
+
+    for ( ; i < mmvar->num_axis; i++ )
+      normalized[i] = 0;
+
     if ( !blend->avar_checked )
       ft_var_load_avar( face );
 
     if ( blend->avar_segment != NULL )
     {
+      FT_TRACE5(( "normalized design coordinates"
+                  " before applying `avar' data:\n" ));
+
       av = blend->avar_segment;
-      for ( i = 0; i < mmvar->num_axis; ++i, ++av )
+      for ( i = 0; i < mmvar->num_axis; i++, av++ )
       {
-        for ( j = 1; j < (FT_UInt)av->pairCount; ++j )
+        for ( j = 1; j < (FT_UInt)av->pairCount; j++ )
+        {
+          FT_TRACE5(( "  %.4f\n", normalized[i] / 65536.0 ));
           if ( normalized[i] < av->correspondence[j].fromCoord )
           {
             normalized[i] =
               FT_MulDiv( normalized[i] - av->correspondence[j - 1].fromCoord,
                          av->correspondence[j].toCoord -
                            av->correspondence[j - 1].toCoord,
                          av->correspondence[j].fromCoord -
                            av->correspondence[j - 1].fromCoord ) +
               av->correspondence[j - 1].toCoord;
             break;
           }
+        }
       }
     }
 
-    error = TT_Set_MM_Blend( face, num_coords, normalized );
+    error = TT_Set_MM_Blend( face, mmvar->num_axis, normalized );
 
   Exit:
     FT_FREE( normalized );
     return error;
   }
 
 
   /*************************************************************************/
   /*************************************************************************/
   /*****                                                               *****/
@@ skipping 42 matching lines @@
     GX_Blend    blend           = face->blend;
     FT_UInt     point_count;
     FT_UShort*  localpoints;
     FT_Short*   deltas;
 
 
     FT_TRACE2(( "CVAR " ));
 
     if ( blend == NULL )
     {
-      FT_TRACE2(( "tt_face_vary_cvt: no blend specified\n" ));
-
+      FT_TRACE2(( "\n"
+                  "tt_face_vary_cvt: no blend specified\n" ));
       error = FT_Err_Ok;
       goto Exit;
     }
 
     if ( face->cvt == NULL )
     {
-      FT_TRACE2(( "tt_face_vary_cvt: no `cvt ' table\n" ));
-
+      FT_TRACE2(( "\n"
+                  "tt_face_vary_cvt: no `cvt ' table\n" ));
       error = FT_Err_Ok;
       goto Exit;
     }
 
     error = face->goto_table( face, TTAG_cvar, stream, &table_len );
     if ( error )
     {
       FT_TRACE2(( "is missing\n" ));
 
       error = FT_Err_Ok;
       goto Exit;
     }
 
     if ( FT_FRAME_ENTER( table_len ) )
     {
       error = FT_Err_Ok;
       goto Exit;
     }
 
     table_start = FT_Stream_FTell( stream );
     if ( FT_GET_LONG() != 0x00010000L )
     {
       FT_TRACE2(( "bad table version\n" ));
 
       error = FT_Err_Ok;
       goto FExit;
     }
 
+    FT_TRACE2(( "loaded\n" ));
+
     if ( FT_NEW_ARRAY( tuple_coords, blend->num_axis )    ||
          FT_NEW_ARRAY( im_start_coords, blend->num_axis ) ||
          FT_NEW_ARRAY( im_end_coords, blend->num_axis )   )
       goto FExit;
 
     tupleCount   = FT_GET_USHORT();
     offsetToData = table_start + FT_GET_USHORT();
 
     /* The documentation implies there are flags packed into the        */
     /* tuplecount, but John Jenkins says that shared points don't apply */
     /* to `cvar', and no other flags are defined.                       */
 
-    for ( i = 0; i < ( tupleCount & 0xFFF ); ++i )
+    FT_TRACE5(( "cvar: there are %d tuples:\n", tupleCount ));
+
+    for ( i = 0; i < ( tupleCount & 0xFFF ); i++ )
     {
       FT_UInt   tupleDataSize;
       FT_UInt   tupleIndex;
       FT_Fixed  apply;
 
 
+      FT_TRACE6(( "  tuple %d:\n", i ));
+
       tupleDataSize = FT_GET_USHORT();
       tupleIndex    = FT_GET_USHORT();
 
       /* There is no provision here for a global tuple coordinate section, */
       /* so John says.  There are no tuple indices, just embedded tuples.  */
 
       if ( tupleIndex & GX_TI_EMBEDDED_TUPLE_COORD )
       {
-        for ( j = 0; j < blend->num_axis; ++j )
-          tuple_coords[j] = FT_GET_SHORT() << 2; /* convert from        */
+        for ( j = 0; j < blend->num_axis; j++ )
+          tuple_coords[j] = FT_GET_SHORT() * 4;  /* convert from        */
                                                  /* short frac to fixed */
       }
       else
       {
         /* skip this tuple; it makes no sense */
 
         if ( tupleIndex & GX_TI_INTERMEDIATE_TUPLE )
-          for ( j = 0; j < 2 * blend->num_axis; ++j )
+          for ( j = 0; j < 2 * blend->num_axis; j++ )
             (void)FT_GET_SHORT();
 
         offsetToData += tupleDataSize;
         continue;
       }
 
       if ( tupleIndex & GX_TI_INTERMEDIATE_TUPLE )
       {
-        for ( j = 0; j < blend->num_axis; ++j )
-          im_start_coords[j] = FT_GET_SHORT() << 2;
-        for ( j = 0; j < blend->num_axis; ++j )
-          im_end_coords[j] = FT_GET_SHORT() << 2;
+        for ( j = 0; j < blend->num_axis; j++ )
+          im_start_coords[j] = FT_GET_SHORT() * 4;
+        for ( j = 0; j < blend->num_axis; j++ )
+          im_end_coords[j] = FT_GET_SHORT() * 4;
       }
 
       apply = ft_var_apply_tuple( blend,
                                   (FT_UShort)tupleIndex,
                                   tuple_coords,
                                   im_start_coords,
                                   im_end_coords );
       if ( /* tuple isn't active for our blend */
            apply == 0                                    ||
            /* global points not allowed,           */
            /* if they aren't local, makes no sense */
            !( tupleIndex & GX_TI_PRIVATE_POINT_NUMBERS ) )
       {
         offsetToData += tupleDataSize;
         continue;
       }
 
       here = FT_Stream_FTell( stream );
 
       FT_Stream_SeekSet( stream, offsetToData );
 
       localpoints = ft_var_readpackedpoints( stream, &point_count );
       deltas      = ft_var_readpackeddeltas( stream,
                                              point_count == 0 ? face->cvt_size
                                                               : point_count );
       if ( localpoints == NULL || deltas == NULL )
-        /* failure, ignore it */;
+        ; /* failure, ignore it */
 
       else if ( localpoints == ALL_POINTS )
       {
+#ifdef FT_DEBUG_LEVEL_TRACE
+        int  count = 0;
+#endif
+
+
+        FT_TRACE7(( "    CVT deltas:\n" ));
+
         /* this means that there are deltas for every entry in cvt */
-        for ( j = 0; j < face->cvt_size; ++j )
-          face->cvt[j] = (FT_Short)( face->cvt[j] +
+        for ( j = 0; j < face->cvt_size; j++ )
+        {
+          FT_Long  orig_cvt = face->cvt[j];
+
+
+          face->cvt[j] = (FT_Short)( orig_cvt +
                                      FT_MulFix( deltas[j], apply ) );
+
+#ifdef FT_DEBUG_LEVEL_TRACE
+          if ( orig_cvt != face->cvt[j] )
+          {
+            FT_TRACE7(( "      %d: %d -> %d\n",
+                        j, orig_cvt, face->cvt[j] ));
+            count++;
+          }
+#endif
+        }
+
+#ifdef FT_DEBUG_LEVEL_TRACE
+        if ( !count )
+          FT_TRACE7(( "      none\n" ));
+#endif
       }
 
       else
       {
-        for ( j = 0; j < point_count; ++j )
+#ifdef FT_DEBUG_LEVEL_TRACE
+        int  count = 0;
+#endif
+
+
+        FT_TRACE7(( "    CVT deltas:\n" ));
+
+        for ( j = 0; j < point_count; j++ )
         {
-          int  pindex = localpoints[j];
+          int      pindex   = localpoints[j];
+          FT_Long  orig_cvt = face->cvt[pindex];
 
-          face->cvt[pindex] = (FT_Short)( face->cvt[pindex] +
+
+          face->cvt[pindex] = (FT_Short)( orig_cvt +
                                           FT_MulFix( deltas[j], apply ) );
+
+#ifdef FT_DEBUG_LEVEL_TRACE
+          if ( orig_cvt != face->cvt[pindex] )
+          {
+            FT_TRACE7(( "      %d: %d -> %d\n",
+                        pindex, orig_cvt, face->cvt[pindex] ));
+            count++;
+          }
+#endif
         }
+
+#ifdef FT_DEBUG_LEVEL_TRACE
+        if ( !count )
+          FT_TRACE7(( "      none\n" ));
+#endif
       }
 
       if ( localpoints != ALL_POINTS )
         FT_FREE( localpoints );
       FT_FREE( deltas );
 
       offsetToData += tupleDataSize;
 
       FT_Stream_SeekSet( stream, here );
     }
 
+    FT_TRACE5(( "\n" ));
+
   FExit:
     FT_FRAME_EXIT();
 
   Exit:
     FT_FREE( tuple_coords );
     FT_FREE( im_start_coords );
     FT_FREE( im_end_coords );
 
     return error;
   }
 
 
+  /* Shift the original coordinates of all points between indices `p1' */
+  /* and `p2', using the same difference as given by index `ref'.      */
+
+  /* modeled after `af_iup_shift' */
+
+  static void
+  tt_delta_shift( int         p1,
+                  int         p2,
+                  int         ref,
+                  FT_Vector*  in_points,
+                  FT_Vector*  out_points )
+  {
+    int        p;
+    FT_Vector  delta;
+
+
+    delta.x = out_points[ref].x - in_points[ref].x;
+    delta.y = out_points[ref].y - in_points[ref].y;
+
+    if ( delta.x == 0 && delta.y == 0 )
+      return;
+
+    for ( p = p1; p < ref; p++ )
+    {
+      out_points[p].x += delta.x;
+      out_points[p].y += delta.y;
+    }
+
+    for ( p = ref + 1; p <= p2; p++ )
+    {
+      out_points[p].x += delta.x;
+      out_points[p].y += delta.y;
+    }
+  }
+
+
+  /* Interpolate the original coordinates of all points with indices */
+  /* between `p1' and `p2', using `ref1' and `ref2' as the reference */
+  /* point indices.                                                  */
+
+  /* modeled after `af_iup_interp', `_iup_worker_interpolate', and */
+  /* `Ins_IUP'                                                     */
+
+  static void
+  tt_delta_interpolate( int         p1,
+                        int         p2,
+                        int         ref1,
+                        int         ref2,
+                        FT_Vector*  in_points,
+                        FT_Vector*  out_points )
+  {
+    int  p, i;
+
+    FT_Pos  out, in1, in2, out1, out2, d1, d2;
+
+
+    if ( p1 > p2 )
+      return;
+
+    /* handle both horizontal and vertical coordinates */
+    for ( i = 0; i <= 1; i++ )
+    {
+      /* shift array pointers so that we can access `foo.y' as `foo.x' */
+      in_points  = (FT_Vector*)( (FT_Pos*)in_points + i );
+      out_points = (FT_Vector*)( (FT_Pos*)out_points + i );
+
+      if ( in_points[ref1].x > in_points[ref2].x )
+      {
+        p    = ref1;
+        ref1 = ref2;
+        ref2 = p;
+      }
+
+      in1  = in_points[ref1].x;
+      in2  = in_points[ref2].x;
+      out1 = out_points[ref1].x;
+      out2 = out_points[ref2].x;
+      d1   = out1 - in1;
+      d2   = out2 - in2;
+
+      if ( out1 == out2 || in1 == in2 )
+      {
+        for ( p = p1; p <= p2; p++ )
+        {
+          out = in_points[p].x;
+
+          if ( out <= in1 )
+            out += d1;
+          else if ( out >= in2 )
+            out += d2;
+          else
+            out = out1;
+
+          out_points[p].x = out;
+        }
+      }
+      else
+      {
+        FT_Fixed  scale = FT_DivFix( out2 - out1, in2 - in1 );
+
+
+        for ( p = p1; p <= p2; p++ )
+        {
+          out = in_points[p].x;
+
+          if ( out <= in1 )
+            out += d1;
+          else if ( out >= in2 )
+            out += d2;
+          else
+            out = out1 + FT_MulFix( out - in1, scale );
+
+          out_points[p].x = out;
+        }
+      }
+    }
+  }
+
+
+  /* Interpolate points without delta values, similar to */
+  /* the `IUP' hinting instruction.                      */
+
+  /* modeled after `Ins_IUP */
+
+  static void
+  tt_handle_deltas( FT_Outline*  outline,
+                    FT_Vector*   in_points,
+                    FT_Bool*     has_delta )
+  {
+    FT_Vector*  out_points;
+
+    FT_Int  first_point;
+    FT_Int  end_point;
+
+    FT_Int  first_delta;
+    FT_Int  cur_delta;
+
+    FT_Int    point;
+    FT_Short  contour;
+
+
+    /* ignore empty outlines */
+    if ( !outline->n_contours )
+      return;
+
+    out_points = outline->points;
+
+    contour = 0;
+    point   = 0;
+
+    do
+    {
+      end_point   = outline->contours[contour];
+      first_point = point;
+
+      /* search first point that has a delta */
+      while ( point <= end_point && !has_delta[point] )
+        point++;
+
+      if ( point <= end_point )
+      {
+        first_delta = point;
+        cur_delta   = point;
+
+        point++;
+
+        while ( point <= end_point )
+        {
+          /* search next point that has a delta  */
+          /* and interpolate intermediate points */
+          if ( has_delta[point] )
+          {
+            tt_delta_interpolate( cur_delta + 1,
+                                  point - 1,
+                                  cur_delta,
+                                  point,
+                                  in_points,
+                                  out_points );
+            cur_delta = point;
+          }
+
+          point++;
+        }
+
+        /* shift contour if we only have a single delta */
+        if ( cur_delta == first_delta )
+          tt_delta_shift( first_point,
+                          end_point,
+                          cur_delta,
+                          in_points,
+                          out_points );
+        else
+        {
+          /* otherwise handle remaining points       */
+          /* at the end and beginning of the contour */
+          tt_delta_interpolate( cur_delta + 1,
+                                end_point,
+                                cur_delta,
+                                first_delta,
+                                in_points,
+                                out_points );
+
+          if ( first_delta > 0 )
+            tt_delta_interpolate( first_point,
+                                  first_delta - 1,
+                                  cur_delta,
+                                  first_delta,
+                                  in_points,
+                                  out_points );
+        }
+      }
+      contour++;
+
+    } while ( contour < outline->n_contours );
+  }
+
+
   /*************************************************************************/
   /*                                                                       */
   /* <Function>                                                            */
-  /*    TT_Vary_Get_Glyph_Deltas                                           */
+  /*    TT_Vary_Apply_Glyph_Deltas                                         */
   /*                                                                       */
   /* <Description>                                                         */
-  /*    Load the appropriate deltas for the current glyph.                 */
+  /*    Apply the appropriate deltas to the current glyph.                 */
   /*                                                                       */
   /* <Input>                                                               */
   /*    face        :: A handle to the target face object.                 */
   /*                                                                       */
   /*    glyph_index :: The index of the glyph being modified.              */
   /*                                                                       */
   /*    n_points    :: The number of the points in the glyph, including    */
   /*                   phantom points.                                     */
   /*                                                                       */
-  /* <Output>                                                              */
-  /*    deltas      :: The array of points to change.                      */
+  /* <InOut>                                                               */
+  /*    outline     :: The outline to change.                              */
   /*                                                                       */
   /* <Return>                                                              */
   /*    FreeType error code.  0 means success.                             */
   /*                                                                       */
   FT_LOCAL_DEF( FT_Error )
-  TT_Vary_Get_Glyph_Deltas( TT_Face      face,
-                            FT_UInt      glyph_index,
-                            FT_Vector*  *deltas,
-                            FT_UInt      n_points )
+  TT_Vary_Apply_Glyph_Deltas( TT_Face      face,
+                              FT_UInt      glyph_index,
+                              FT_Outline*  outline,
+                              FT_UInt      n_points )
   {
     FT_Stream   stream = face->root.stream;
     FT_Memory   memory = stream->memory;
     GX_Blend    blend  = face->blend;
-    FT_Vector*  delta_xy = NULL;
+
+    FT_Vector*  points_org = NULL;
+    FT_Bool*    has_delta  = NULL;
 
     FT_Error    error;
     FT_ULong    glyph_start;
     FT_UInt     tupleCount;
     FT_ULong    offsetToData;
     FT_ULong    here;
     FT_UInt     i, j;
     FT_Fixed*   tuple_coords    = NULL;
     FT_Fixed*   im_start_coords = NULL;
     FT_Fixed*   im_end_coords   = NULL;
     FT_UInt     point_count, spoint_count = 0;
     FT_UShort*  sharedpoints = NULL;
     FT_UShort*  localpoints  = NULL;
     FT_UShort*  points;
     FT_Short    *deltas_x, *deltas_y;
 
 
     if ( !face->doblend || blend == NULL )
       return FT_THROW( Invalid_Argument );
 
-    /* to be freed by the caller */
-    if ( FT_NEW_ARRAY( delta_xy, n_points ) )
-      goto Exit;
-    *deltas = delta_xy;
-
     if ( glyph_index >= blend->gv_glyphcnt      ||
          blend->glyphoffsets[glyph_index] ==
            blend->glyphoffsets[glyph_index + 1] )
-      return FT_Err_Ok;               /* no variation data for this glyph */
+    {
+      FT_TRACE2(( "TT_Vary_Apply_Glyph_Deltas:"
+                  " no variation data for this glyph\n" ));
+      return FT_Err_Ok;
+    }
+
+    if ( FT_NEW_ARRAY( points_org, n_points ) ||
+         FT_NEW_ARRAY( has_delta, n_points )  )
+      goto Fail1;
 
     if ( FT_STREAM_SEEK( blend->glyphoffsets[glyph_index] )   ||
          FT_FRAME_ENTER( blend->glyphoffsets[glyph_index + 1] -
                            blend->glyphoffsets[glyph_index] ) )
       goto Fail1;
 
     glyph_start = FT_Stream_FTell( stream );
 
     /* each set of glyph variation data is formatted similarly to `cvar' */
     /* (except we get shared points and global tuples)                   */
@@ skipping 11 matching lines @@
       here = FT_Stream_FTell( stream );
 
       FT_Stream_SeekSet( stream, offsetToData );
 
       sharedpoints = ft_var_readpackedpoints( stream, &spoint_count );
       offsetToData = FT_Stream_FTell( stream );
 
       FT_Stream_SeekSet( stream, here );
     }
 
-    for ( i = 0; i < ( tupleCount & GX_TC_TUPLE_COUNT_MASK ); ++i )
+    FT_TRACE5(( "gvar: there are %d tuples:\n", tupleCount ));
+
+    for ( i = 0; i < ( tupleCount & GX_TC_TUPLE_COUNT_MASK ); i++ )
     {
       FT_UInt   tupleDataSize;
       FT_UInt   tupleIndex;
       FT_Fixed  apply;
 
 
+      FT_TRACE6(( "  tuple %d:\n", i ));
+
       tupleDataSize = FT_GET_USHORT();
       tupleIndex    = FT_GET_USHORT();
 
       if ( tupleIndex & GX_TI_EMBEDDED_TUPLE_COORD )
       {
-        for ( j = 0; j < blend->num_axis; ++j )
-          tuple_coords[j] = FT_GET_SHORT() << 2;  /* convert from        */
+        for ( j = 0; j < blend->num_axis; j++ )
+          tuple_coords[j] = FT_GET_SHORT() * 4;   /* convert from        */
                                                   /* short frac to fixed */
       }
       else if ( ( tupleIndex & GX_TI_TUPLE_INDEX_MASK ) >= blend->tuplecount )
       {
         error = FT_THROW( Invalid_Table );
-        goto Fail3;
+        goto Fail2;
       }
       else
-      {
         FT_MEM_COPY(
           tuple_coords,
-          &blend->tuplecoords[(tupleIndex & 0xFFF) * blend->num_axis],
+          &blend->tuplecoords[( tupleIndex & 0xFFF ) * blend->num_axis],
           blend->num_axis * sizeof ( FT_Fixed ) );
-      }
 
       if ( tupleIndex & GX_TI_INTERMEDIATE_TUPLE )
       {
-        for ( j = 0; j < blend->num_axis; ++j )
-          im_start_coords[j] = FT_GET_SHORT() << 2;
-        for ( j = 0; j < blend->num_axis; ++j )
-          im_end_coords[j] = FT_GET_SHORT() << 2;
+        for ( j = 0; j < blend->num_axis; j++ )
+          im_start_coords[j] = FT_GET_SHORT() * 4;
+        for ( j = 0; j < blend->num_axis; j++ )
+          im_end_coords[j] = FT_GET_SHORT() * 4;
       }
 
       apply = ft_var_apply_tuple( blend,
                                   (FT_UShort)tupleIndex,
                                   tuple_coords,
                                   im_start_coords,
                                   im_end_coords );
 
       if ( apply == 0 )              /* tuple isn't active for our blend */
       {
@@ skipping 21 matching lines @@
                                                            : point_count );
       deltas_y = ft_var_readpackeddeltas( stream,
                                           point_count == 0 ? n_points
                                                            : point_count );
 
       if ( points == NULL || deltas_y == NULL || deltas_x == NULL )
         ; /* failure, ignore it */
 
       else if ( points == ALL_POINTS )
       {
+#ifdef FT_DEBUG_LEVEL_TRACE
+        int  count = 0;
+#endif
+
+
+        FT_TRACE7(( "    point deltas:\n" ));
+
         /* this means that there are deltas for every point in the glyph */
-        for ( j = 0; j < n_points; ++j )
+        for ( j = 0; j < n_points; j++ )
         {
-          delta_xy[j].x += FT_MulFix( deltas_x[j], apply );
-          delta_xy[j].y += FT_MulFix( deltas_y[j], apply );
+#ifdef FT_DEBUG_LEVEL_TRACE
+          FT_Vector  point_org = outline->points[j];
+#endif
+
+
+          outline->points[j].x += FT_MulFix( deltas_x[j], apply );
+          outline->points[j].y += FT_MulFix( deltas_y[j], apply );
+
+#ifdef FT_DEBUG_LEVEL_TRACE
+          if ( ( point_org.x != outline->points[j].x ) ||
+               ( point_org.y != outline->points[j].y ) )
+          {
+            FT_TRACE7(( "      %d: (%d, %d) -> (%d, %d)\n",
+                        j,
+                        point_org.x,
+                        point_org.y,
+                        outline->points[j].x,
+                        outline->points[j].y ));
+            count++;
+          }
+#endif
         }
+
+#ifdef FT_DEBUG_LEVEL_TRACE
+        if ( !count )
+          FT_TRACE7(( "      none\n" ));
+#endif
       }
 
       else
       {
-        for ( j = 0; j < point_count; ++j )
+#ifdef FT_DEBUG_LEVEL_TRACE
+        int  count = 0;
+#endif
+
+
+        /* we have to interpolate the missing deltas similar to the */
+        /* IUP bytecode instruction                                 */
+        for ( j = 0; j < n_points; j++ )
         {
-          if ( localpoints[j] >= n_points )
+          points_org[j] = outline->points[j];
+          has_delta[j]  = FALSE;
+        }
+
+        for ( j = 0; j < point_count; j++ )
+        {
+          FT_UShort  idx = localpoints[j];
+
+
+          if ( idx >= n_points )
             continue;
 
-          delta_xy[localpoints[j]].x += FT_MulFix( deltas_x[j], apply );
-          delta_xy[localpoints[j]].y += FT_MulFix( deltas_y[j], apply );
+          has_delta[idx] = TRUE;
+
+          outline->points[idx].x += FT_MulFix( deltas_x[j], apply );
+          outline->points[idx].y += FT_MulFix( deltas_y[j], apply );
         }
+
+        /* no need to handle phantom points here,      */
+        /* since solitary points can't be interpolated */
+        tt_handle_deltas( outline,
+                          points_org,
+                          has_delta );
+
+#ifdef FT_DEBUG_LEVEL_TRACE
+        FT_TRACE7(( "    point deltas:\n" ));
+
+        for ( j = 0; j < n_points; j++)
+        {
+          if ( ( points_org[j].x != outline->points[j].x ) ||
+               ( points_org[j].y != outline->points[j].y ) )
+          {
+            FT_TRACE7(( "      %d: (%d, %d) -> (%d, %d)\n",
+                        j,
+                        points_org[j].x,
+                        points_org[j].y,
+                        outline->points[j].x,
+                        outline->points[j].y ));
+            count++;
+          }
+        }
+
+        if ( !count )
+          FT_TRACE7(( "      none\n" ));
+#endif
       }
 
       if ( localpoints != ALL_POINTS )
         FT_FREE( localpoints );
       FT_FREE( deltas_x );
       FT_FREE( deltas_y );
 
       offsetToData += tupleDataSize;
 
       FT_Stream_SeekSet( stream, here );
     }
 
-  Fail3:
+    FT_TRACE5(( "\n" ));
+
+  Fail2:
     FT_FREE( tuple_coords );
     FT_FREE( im_start_coords );
     FT_FREE( im_end_coords );
 
-  Fail2:
     FT_FRAME_EXIT();
 
   Fail1:
-    if ( error )
-    {
-      FT_FREE( delta_xy );
-      *deltas = NULL;
-    }
+    FT_FREE( points_org );
+    FT_FREE( has_delta );
 
-  Exit:
     return error;
   }
 
 
   /*************************************************************************/
   /*                                                                       */
   /* <Function>                                                            */
   /*    tt_done_blend                                                      */
   /*                                                                       */
   /* <Description>                                                         */
-  /*    Frees the blend internal data structure.                           */
+  /*    Free the blend internal data structure.                            */
   /*                                                                       */
   FT_LOCAL_DEF( void )
   tt_done_blend( FT_Memory  memory,
                  GX_Blend   blend )
   {
     if ( blend != NULL )
     {
       FT_UInt  i;
 
 
       FT_FREE( blend->normalizedcoords );
       FT_FREE( blend->mmvar );
 
       if ( blend->avar_segment != NULL )
       {
-        for ( i = 0; i < blend->num_axis; ++i )
+        for ( i = 0; i < blend->num_axis; i++ )
           FT_FREE( blend->avar_segment[i].correspondence );
         FT_FREE( blend->avar_segment );
       }
 
       FT_FREE( blend->tuplecoords );
       FT_FREE( blend->glyphoffsets );
       FT_FREE( blend );
     }
   }
 
 #endif /* TT_CONFIG_OPTION_GX_VAR_SUPPORT */
 
 
 /* END */