update for HEAD-2003050101
[reactos.git] / lib / freetype / src / pshinter / pshglob.c
diff --git a/lib/freetype/src/pshinter/pshglob.c b/lib/freetype/src/pshinter/pshglob.c
new file mode 100644 (file)
index 0000000..e5ead54
--- /dev/null
@@ -0,0 +1,743 @@
+/***************************************************************************/
+/*                                                                         */
+/*  pshglob.c                                                              */
+/*                                                                         */
+/*    PostScript hinter global hinting management (body).                  */
+/*    Inspired by the new auto-hinter module.                              */
+/*                                                                         */
+/*  Copyright 2001, 2002 by                                                */
+/*  David Turner, Robert Wilhelm, and Werner Lemberg.                      */
+/*                                                                         */
+/*  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.                                        */
+/*                                                                         */
+/***************************************************************************/
+
+
+#include <ft2build.h>
+#include FT_FREETYPE_H
+#include FT_INTERNAL_OBJECTS_H
+#include "pshglob.h"
+
+#ifdef DEBUG_HINTER
+  PSH_Globals  ps_debug_globals = 0;
+#endif
+
+
+  /*************************************************************************/
+  /*************************************************************************/
+  /*****                                                               *****/
+  /*****                       STANDARD WIDTHS                         *****/
+  /*****                                                               *****/
+  /*************************************************************************/
+  /*************************************************************************/
+
+
+  /* scale the widths/heights table */
+  static void
+  psh_globals_scale_widths( PSH_Globals  globals,
+                            FT_UInt      direction )
+  {
+    PSH_Dimension  dim   = &globals->dimension[direction];
+    PSH_Widths     stdw  = &dim->stdw;
+    FT_UInt        count = stdw->count;
+    PSH_Width      width = stdw->widths;
+    PSH_Width      stand = width;               /* standard width/height */
+    FT_Fixed       scale = dim->scale_mult;
+
+
+    if ( count > 0 )
+    {
+      width->cur = FT_MulFix( width->org, scale );
+      width->fit = FT_RoundFix( width->cur );
+
+      width++;
+      count--;
+
+      for ( ; count > 0; count--, width++ )
+      {
+        FT_Pos  w, dist;
+
+
+        w    = FT_MulFix( width->org, scale );
+        dist = w - stand->cur;
+
+        if ( dist < 0 )
+          dist = -dist;
+
+        if ( dist < 128 )
+          w = stand->cur;
+
+        width->cur = w;
+        width->fit = FT_RoundFix( w );
+      }
+    }
+  }
+
+
+  /* org_width is is font units, result in device pixels, 26.6 format */
+  FT_LOCAL_DEF( FT_Pos )
+  psh_dimension_snap_width( PSH_Dimension  dimension,
+                            FT_Int         org_width )
+  {
+    FT_UInt  n;
+    FT_Pos   width     = FT_MulFix( org_width, dimension->scale_mult );
+    FT_Pos   best      = 64 + 32 + 2;
+    FT_Pos   reference = width;
+
+
+    for ( n = 0; n < dimension->stdw.count; n++ )
+    {
+      FT_Pos  w;
+      FT_Pos  dist;
+
+
+      w = dimension->stdw.widths[n].cur;
+      dist = width - w;
+      if ( dist < 0 )
+        dist = -dist;
+      if ( dist < best )
+      {
+        best      = dist;
+        reference = w;
+      }
+    }
+
+    if ( width >= reference )
+    {
+      width -= 0x21;
+      if ( width < reference )
+        width = reference;
+    }
+    else
+    {
+      width += 0x21;
+      if ( width > reference )
+        width = reference;
+    }
+
+    return width;
+  }
+
+
+  /*************************************************************************/
+  /*************************************************************************/
+  /*****                                                               *****/
+  /*****                       BLUE ZONES                              *****/
+  /*****                                                               *****/
+  /*************************************************************************/
+  /*************************************************************************/
+
+  static void
+  psh_blues_set_zones_0( PSH_Blues       target,
+                         FT_Bool         is_others,
+                         FT_UInt         read_count,
+                         FT_Short*       read,
+                         PSH_Blue_Table  top_table,
+                         PSH_Blue_Table  bot_table )
+  {
+    FT_UInt  count_top = top_table->count;
+    FT_UInt  count_bot = bot_table->count;
+    FT_Bool  first     = 1;
+
+    FT_UNUSED( target );
+
+
+    for ( ; read_count > 0; read_count -= 2 )
+    {
+      FT_Int         reference, delta;
+      FT_UInt        count;
+      PSH_Blue_Zone  zones, zone;
+      FT_Bool        top;
+
+
+      /* read blue zone entry, and select target top/bottom zone */
+      top = 0;
+      if ( first || is_others )
+      {
+        reference = read[1];
+        delta     = read[0] - reference;
+
+        zones = bot_table->zones;
+        count = count_bot;
+        first = 0;
+      }
+      else
+      {
+        reference = read[0];
+        delta     = read[1] - reference;
+
+        zones = top_table->zones;
+        count = count_top;
+        top   = 1;
+      }
+
+      /* insert into sorted table */
+      zone = zones;
+      for ( ; count > 0; count--, zone++ )
+      {
+        if ( reference < zone->org_ref )
+          break;
+
+        if ( reference == zone->org_ref )
+        {
+          FT_Int  delta0 = zone->org_delta;
+
+
+          /* we have two zones on the same reference position -- */
+          /* only keep the largest one                           */
+          if ( delta < 0 )
+          {
+            if ( delta < delta0 )
+              zone->org_delta = delta;
+          }
+          else
+          {
+            if ( delta > delta0 )
+              zone->org_delta = delta;
+          }
+          goto Skip;
+        }
+      }
+
+      for ( ; count > 0; count-- )
+        zone[count] = zone[count-1];
+
+      zone->org_ref   = reference;
+      zone->org_delta = delta;
+
+      if ( top )
+        count_top++;
+      else
+        count_bot++;
+
+    Skip:
+      read += 2;
+    }
+
+    top_table->count = count_top;
+    bot_table->count = count_bot;
+  }
+
+
+  /* Re-read blue zones from the original fonts and store them into out */
+  /* private structure.  This function re-orders, sanitizes and         */
+  /* fuzz-expands the zones as well.                                    */
+  static void
+  psh_blues_set_zones( PSH_Blues  target,
+                       FT_UInt    count,
+                       FT_Short*  blues,
+                       FT_UInt    count_others,
+                       FT_Short*  other_blues,
+                       FT_Int     fuzz,
+                       FT_Int     family )
+  {
+    PSH_Blue_Table  top_table, bot_table;
+    FT_Int          count_top, count_bot;
+
+
+    if ( family )
+    {
+      top_table = &target->family_top;
+      bot_table = &target->family_bottom;
+    }
+    else
+    {
+      top_table = &target->normal_top;
+      bot_table = &target->normal_bottom;
+    }
+
+    /* read the input blue zones, and build two sorted tables  */
+    /* (one for the top zones, the other for the bottom zones) */
+    top_table->count = 0;
+    bot_table->count = 0;
+
+    /* first, the blues */
+    psh_blues_set_zones_0( target, 0,
+                           count, blues, top_table, bot_table );
+    psh_blues_set_zones_0( target, 1,
+                           count_others, other_blues, top_table, bot_table );
+
+    count_top = top_table->count;
+    count_bot = bot_table->count;
+
+    /* sanitize top table */
+    if ( count_top > 0 )
+    {
+      PSH_Blue_Zone  zone = top_table->zones;
+
+
+      for ( count = count_top; count > 0; count--, zone++ )
+      {
+        FT_Int  delta;
+
+
+        if ( count > 1 )
+        {
+          delta = zone[1].org_ref - zone[0].org_ref;
+          if ( zone->org_delta > delta )
+            zone->org_delta = delta;
+        }
+
+        zone->org_bottom = zone->org_ref;
+        zone->org_top    = zone->org_delta + zone->org_ref;
+      }
+    }
+
+    /* sanitize bottom table */
+    if ( count_bot > 0 )
+    {
+      PSH_Blue_Zone  zone = bot_table->zones;
+
+
+      for ( count = count_bot; count > 0; count--, zone++ )
+      {
+        FT_Int  delta;
+
+
+        if ( count > 1 )
+        {
+          delta = zone[0].org_ref - zone[1].org_ref;
+          if ( zone->org_delta < delta )
+            zone->org_delta = delta;
+        }
+
+        zone->org_top    = zone->org_ref;
+        zone->org_bottom = zone->org_delta + zone->org_ref;
+      }
+    }
+
+    /* expand top and bottom tables with blue fuzz */
+    {
+      FT_Int         dim, top, bot, delta;
+      PSH_Blue_Zone  zone;
+
+
+      zone  = top_table->zones;
+      count = count_top;
+
+      for ( dim = 1; dim >= 0; dim-- )
+      {
+        if ( count > 0 )
+        {
+          /* expand the bottom of the lowest zone normally */
+          zone->org_bottom -= fuzz;
+
+          /* expand the top and bottom of intermediate zones;    */
+          /* checking that the interval is smaller than the fuzz */
+          top = zone->org_top;
+
+          for ( count--; count > 0; count-- )
+          {
+            bot   = zone[1].org_bottom;
+            delta = bot - top;
+
+            if ( delta < 2 * fuzz )
+              zone[0].org_top = zone[1].org_bottom = top + delta / 2;
+            else
+            {
+              zone[0].org_top    = top + fuzz;
+              zone[1].org_bottom = bot - fuzz;
+            }
+
+            zone++;
+            top = zone->org_top;
+          }
+
+          /* expand the top of the highest zone normally */
+          zone->org_top = top + fuzz;
+        }
+        zone  = bot_table->zones;
+        count = count_bot;
+      }
+    }
+  }
+
+
+  /* reset the blues table when the device transform changes */
+  static void
+  psh_blues_scale_zones( PSH_Blues  blues,
+                         FT_Fixed   scale,
+                         FT_Pos     delta )
+  {
+    FT_UInt         count;
+    FT_UInt         num;
+    PSH_Blue_Table  table = 0;
+
+    /*                                                        */
+    /* Determine whether we need to suppress overshoots or    */
+    /* not.  We simply need to compare the vertical scale     */
+    /* parameter to the raw bluescale value.  Here is why:    */
+    /*                                                        */
+    /*   We need to suppress overshoots for all pointsizes.   */
+    /*   At 300dpi that satisfy:                              */
+    /*                                                        */
+    /*      pointsize < 240*bluescale + 0.49                  */
+    /*                                                        */
+    /*   This corresponds to:                                 */
+    /*                                                        */
+    /*      pixelsize < 1000*bluescale + 49/24                */
+    /*                                                        */
+    /*      scale*EM_Size < 1000*bluescale + 49/24            */
+    /*                                                        */
+    /*   However, for normal Type 1 fonts, EM_Size is 1000!   */
+    /*   We thus only check:                                  */
+    /*                                                        */
+    /*      scale < bluescale + 49/24000                      */
+    /*                                                        */
+    /*   which we shorten to                                  */
+    /*                                                        */
+    /*      "scale < bluescale"                               */
+    /*                                                        */
+    blues->no_overshoots = FT_BOOL( scale < blues->blue_scale );
+
+    /*                                                        */
+    /*  The blue threshold is the font units distance under   */
+    /*  which overshoots are suppressed due to the BlueShift  */
+    /*  even if the scale is greater than BlueScale.          */
+    /*                                                        */
+    /*  It is the smallest distance such that                 */
+    /*                                                        */
+    /*    dist <= BlueShift && dist*scale <= 0.5 pixels       */
+    /*                                                        */
+    {
+      FT_Int  threshold = blues->blue_shift;
+
+
+      while ( threshold > 0 && FT_MulFix( threshold, scale ) > 32 )
+        threshold --;
+
+      blues->blue_threshold = threshold;
+    }
+
+    for ( num = 0; num < 4; num++ )
+    {
+      PSH_Blue_Zone  zone;
+
+
+      switch ( num )
+      {
+      case 0:
+        table = &blues->normal_top;
+        break;
+      case 1:
+        table = &blues->normal_bottom;
+        break;
+      case 2:
+        table = &blues->family_top;
+        break;
+      default:
+        table = &blues->family_bottom;
+        break;
+      }
+
+      zone  = table->zones;
+      count = table->count;
+      for ( ; count > 0; count--, zone++ )
+      {
+        zone->cur_top    = FT_MulFix( zone->org_top,    scale ) + delta;
+        zone->cur_bottom = FT_MulFix( zone->org_bottom, scale ) + delta;
+        zone->cur_ref    = FT_MulFix( zone->org_ref,    scale ) + delta;
+        zone->cur_delta  = FT_MulFix( zone->org_delta,  scale );
+
+        /* round scaled reference position */
+        zone->cur_ref = ( zone->cur_ref + 32 ) & -64;
+
+#if 0
+        if ( zone->cur_ref > zone->cur_top )
+          zone->cur_ref -= 64;
+        else if ( zone->cur_ref < zone->cur_bottom )
+          zone->cur_ref += 64;
+#endif
+      }
+    }
+
+    /* process the families now */
+
+    for ( num = 0; num < 2; num++ )
+    {
+      PSH_Blue_Zone   zone1, zone2;
+      FT_UInt         count1, count2;
+      PSH_Blue_Table  normal, family;
+
+
+      switch ( num )
+      {
+      case 0:
+        normal = &blues->normal_top;
+        family = &blues->family_top;
+        break;
+
+      default:
+        normal = &blues->normal_bottom;
+        family = &blues->family_bottom;
+      }
+
+      zone1  = normal->zones;
+      count1 = normal->count;
+
+      for ( ; count1 > 0; count1--, zone1++ )
+      {
+        /* try to find a family zone whose reference position is less */
+        /* than 1 pixel far from the current zone                     */
+        zone2  = family->zones;
+        count2 = family->count;
+
+        for ( ; count2 > 0; count2--, zone2++ )
+        {
+          FT_Pos  Delta;
+
+
+          Delta = zone1->org_ref - zone2->org_ref;
+          if ( Delta < 0 )
+            Delta = -Delta;
+
+          if ( FT_MulFix( Delta, scale ) < 64 )
+          {
+            zone1->cur_top    = zone2->cur_top;
+            zone1->cur_bottom = zone2->cur_bottom;
+            zone1->cur_ref    = zone2->cur_ref;
+            zone1->cur_delta  = zone2->cur_delta;
+            break;
+          }
+        }
+      }
+    }
+  }
+
+
+  FT_LOCAL_DEF( void )
+  psh_blues_snap_stem( PSH_Blues      blues,
+                       FT_Int         stem_top,
+                       FT_Int         stem_bot,
+                       PSH_Alignment  alignment )
+  {
+    PSH_Blue_Table  table;
+    FT_UInt         count;
+    FT_Pos          delta;
+    PSH_Blue_Zone   zone;
+    FT_Int          no_shoots;
+
+
+    alignment->align = PSH_BLUE_ALIGN_NONE;
+
+    no_shoots = blues->no_overshoots;
+
+    /* lookup stem top in top zones table */
+    table = &blues->normal_top;
+    count = table->count;
+    zone  = table->zones;
+
+    for ( ; count > 0; count--, zone++ )
+    {
+      delta = stem_top - zone->org_bottom;
+      if ( delta < -blues->blue_fuzz )
+        break;
+
+      if ( stem_top <= zone->org_top + blues->blue_fuzz )
+      {
+        if ( no_shoots || delta <= blues->blue_threshold )
+        {
+          alignment->align    |= PSH_BLUE_ALIGN_TOP;
+          alignment->align_top = zone->cur_ref;
+        }
+        break;
+      }
+    }
+
+    /* look up stem bottom in bottom zones table */
+    table = &blues->normal_bottom;
+    count = table->count;
+    zone  = table->zones + count-1;
+
+    for ( ; count > 0; count--, zone-- )
+    {
+      delta = zone->org_top - stem_bot;
+      if ( delta < -blues->blue_fuzz )
+        break;
+
+      if ( stem_bot >= zone->org_bottom - blues->blue_fuzz )
+      {
+        if ( no_shoots || delta < blues->blue_shift )
+        {
+          alignment->align    |= PSH_BLUE_ALIGN_BOT;
+          alignment->align_bot = zone->cur_ref;
+        }
+        break;
+      }
+    }
+  }
+
+
+  /*************************************************************************/
+  /*************************************************************************/
+  /*****                                                               *****/
+  /*****                        GLOBAL HINTS                           *****/
+  /*****                                                               *****/
+  /*************************************************************************/
+  /*************************************************************************/
+
+  static void
+  psh_globals_destroy( PSH_Globals  globals )
+  {
+    if ( globals )
+    {
+      FT_Memory  memory;
+
+
+      memory = globals->memory;
+      globals->dimension[0].stdw.count = 0;
+      globals->dimension[1].stdw.count = 0;
+
+      globals->blues.normal_top.count    = 0;
+      globals->blues.normal_bottom.count = 0;
+      globals->blues.family_top.count    = 0;
+      globals->blues.family_bottom.count = 0;
+
+      FT_FREE( globals );
+
+#ifdef DEBUG_HINTER
+      ps_debug_globals = 0;
+#endif
+    }
+  }
+
+
+  static FT_Error
+  psh_globals_new( FT_Memory     memory,
+                   T1_Private*   priv,
+                   PSH_Globals  *aglobals )
+  {
+    PSH_Globals  globals;
+    FT_Error     error;
+
+
+    if ( !FT_NEW( globals ) )
+    {
+      FT_UInt    count;
+      FT_Short*  read;
+
+
+      globals->memory = memory;
+
+      /* copy standard widths */
+      {
+        PSH_Dimension  dim   = &globals->dimension[1];
+        PSH_Width      write = dim->stdw.widths;
+
+
+        write->org = priv->standard_width[0];
+        write++;
+
+        read = priv->snap_widths;
+        for ( count = priv->num_snap_widths; count > 0; count-- )
+        {
+          write->org = *read;
+          write++;
+          read++;
+        }
+
+        dim->stdw.count = write - dim->stdw.widths;
+      }
+
+      /* copy standard heights */
+      {
+        PSH_Dimension  dim = &globals->dimension[0];
+        PSH_Width      write = dim->stdw.widths;
+
+
+        write->org = priv->standard_height[0];
+        write++;                           
+        read = priv->snap_heights;
+        for ( count = priv->num_snap_heights; count > 0; count-- )
+        {
+          write->org = *read;
+          write++;
+          read++;
+        }
+
+        dim->stdw.count = write - dim->stdw.widths;
+      }
+
+      /* copy blue zones */
+      psh_blues_set_zones( &globals->blues, priv->num_blue_values,
+                           priv->blue_values, priv->num_other_blues,
+                           priv->other_blues, priv->blue_fuzz, 0 );
+
+      psh_blues_set_zones( &globals->blues, priv->num_family_blues,
+                           priv->family_blues, priv->num_family_other_blues,
+                           priv->family_other_blues, priv->blue_fuzz, 1 );
+
+      globals->blues.blue_scale = priv->blue_scale
+                                  ? priv->blue_scale
+                                  : 0x28937L;   /* 0.039625 * 0x400000L */
+
+      globals->blues.blue_shift = priv->blue_shift
+                                  ? priv->blue_shift
+                                  : 7;
+
+      globals->blues.blue_fuzz = priv->blue_fuzz;
+
+      globals->dimension[0].scale_mult  = 0;
+      globals->dimension[0].scale_delta = 0;
+      globals->dimension[1].scale_mult  = 0;
+      globals->dimension[1].scale_delta = 0;
+
+#ifdef DEBUG_HINTER
+      ps_debug_globals = globals;
+#endif
+    }
+
+    *aglobals = globals;
+    return error;
+  }
+
+
+  static FT_Error
+  psh_globals_set_scale( PSH_Globals  globals,
+                         FT_Fixed     x_scale,
+                         FT_Fixed     y_scale,
+                         FT_Fixed     x_delta,
+                         FT_Fixed     y_delta )
+  {
+    PSH_Dimension  dim = &globals->dimension[0];
+
+
+    dim = &globals->dimension[0];
+    if ( x_scale != dim->scale_mult  ||
+         x_delta != dim->scale_delta )
+    {
+      dim->scale_mult  = x_scale;
+      dim->scale_delta = x_delta;
+
+      psh_globals_scale_widths( globals, 0 );
+    }
+
+    dim = &globals->dimension[1];
+    if ( y_scale != dim->scale_mult  ||
+         y_delta != dim->scale_delta )
+    {
+      dim->scale_mult  = y_scale;
+      dim->scale_delta = y_delta;
+
+      psh_globals_scale_widths( globals, 1 );
+      psh_blues_scale_zones( &globals->blues, y_scale, y_delta );
+    }
+
+    return 0;
+  }
+
+
+  FT_LOCAL_DEF( void )
+  psh_globals_funcs_init( PSH_Globals_FuncsRec*  funcs )
+  {
+    funcs->create    = psh_globals_new;
+    funcs->set_scale = psh_globals_set_scale;
+    funcs->destroy   = psh_globals_destroy;
+  }
+
+
+/* END */