aboutsummaryrefslogtreecommitdiff
path: root/freetype/src/base/ftsynth.c
blob: 4f2396e9fdb1a35bc4aa8cdf443f10f7c86e56fb (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
/***************************************************************************/
/*                                                                         */
/*  ftsynth.c                                                              */
/*                                                                         */
/*    FreeType synthesizing code for emboldening and slanting (body).      */
/*                                                                         */
/*  Copyright 2000-2001, 2002, 2003, 2004, 2005, 2006 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_SYNTHESIS_H
#include <freetype/internal/ftobjs.h>
#include FT_OUTLINE_H
#include FT_BITMAP_H


  /*************************************************************************/
  /*************************************************************************/
  /****                                                                 ****/
  /****   EXPERIMENTAL OBLIQUING SUPPORT                                ****/
  /****                                                                 ****/
  /*************************************************************************/
  /*************************************************************************/

  /* documentation is in ftsynth.h */

  FT_EXPORT_DEF( void )
  FT_GlyphSlot_Oblique( FT_GlyphSlot  slot )
  {
    FT_Matrix    transform;
    FT_Outline*  outline = &slot->outline;


    /* only oblique outline glyphs */
    if ( slot->format != FT_GLYPH_FORMAT_OUTLINE )
      return;

    /* we don't touch the advance width */

    /* For italic, simply apply a shear transform, with an angle */
    /* of about 12 degrees.                                      */

    transform.xx = 0x10000L;
    transform.yx = 0x00000L;

    transform.xy = 0x06000L;
    transform.yy = 0x10000L;

    FT_Outline_Transform( outline, &transform );
  }


  /*************************************************************************/
  /*************************************************************************/
  /****                                                                 ****/
  /****   EXPERIMENTAL EMBOLDENING/OUTLINING SUPPORT                    ****/
  /****                                                                 ****/
  /*************************************************************************/
  /*************************************************************************/


  /* documentation is in ftsynth.h */

  FT_EXPORT_DEF( void )
  FT_GlyphSlot_Embolden( FT_GlyphSlot  slot )
  {
    FT_Library  library = slot->library;
    FT_Face     face    = slot->face;
    FT_Error    error;
    FT_Pos      xstr, ystr;


    if ( slot->format != FT_GLYPH_FORMAT_OUTLINE &&
         slot->format != FT_GLYPH_FORMAT_BITMAP )
      return;

    /* some reasonable strength */
    xstr = FT_MulFix( face->units_per_EM,
                      face->size->metrics.y_scale ) / 24;
    ystr = xstr;

    if ( slot->format == FT_GLYPH_FORMAT_OUTLINE )
    {
      error = FT_Outline_Embolden( &slot->outline, xstr );
      /* ignore error */

      /* this is more than enough for most glyphs; if you need accurate */
      /* values, you have to call FT_Outline_Get_CBox                   */
      xstr = xstr * 2;
      ystr = xstr;
    }
    else if ( slot->format == FT_GLYPH_FORMAT_BITMAP )
    {
      /* round to full pixels */
      xstr &= ~63;
      if ( xstr == 0 )
        xstr = 1 << 6;
      ystr &= ~63;

      error = FT_GlyphSlot_Own_Bitmap( slot );
      if ( error )
        return;

      error = FT_Bitmap_Embolden( library, &slot->bitmap, xstr, ystr );
      if ( error )
        return;
    }

    if ( slot->advance.x )
      slot->advance.x += xstr;

    if ( slot->advance.y )
      slot->advance.y += ystr;

    slot->metrics.width        += xstr;
    slot->metrics.height       += ystr;
    slot->metrics.horiBearingY += ystr;
    slot->metrics.horiAdvance  += xstr;
    slot->metrics.vertBearingX -= xstr / 2;
    slot->metrics.vertBearingY += ystr;
    slot->metrics.vertAdvance  += ystr;

    if ( slot->format == FT_GLYPH_FORMAT_BITMAP )
      slot->bitmap_top += ystr >> 6;
  }


/* END */