XFA: merge patch from CL 817753002
[pdfium.git] / core / src / fxge / fx_freetype / fxft2.5.01 / src / base / ftsynth.c
1 /***************************************************************************/
2 /*                                                                         */
3 /*  ftsynth.c                                                              */
4 /*                                                                         */
5 /*    FreeType synthesizing code for emboldening and slanting (body).      */
6 /*                                                                         */
7 /*  Copyright 2000-2006, 2010, 2012 by                                     */
8 /*  David Turner, Robert Wilhelm, and Werner Lemberg.                      */
9 /*                                                                         */
10 /*  This file is part of the FreeType project, and may only be used,       */
11 /*  modified, and distributed under the terms of the FreeType project      */
12 /*  license, LICENSE.TXT.  By continuing to use, modify, or distribute     */
13 /*  this file you indicate that you have read the license and              */
14 /*  understand and accept it fully.                                        */
15 /*                                                                         */
16 /***************************************************************************/
17
18
19 #include "../../include/ft2build.h"
20 #include "../../include/freetype/ftsynth.h"
21 #include "../../include/freetype/internal/ftdebug.h"
22 #include "../../include/freetype/internal/ftobjs.h"
23 #include "../../include/freetype/ftoutln.h"
24 #include "../../include/freetype/ftbitmap.h"
25
26
27   /*************************************************************************/
28   /*                                                                       */
29   /* The macro FT_COMPONENT is used in trace mode.  It is an implicit      */
30   /* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log  */
31   /* messages during execution.                                            */
32   /*                                                                       */
33 #undef  FT_COMPONENT
34 #define FT_COMPONENT  trace_synth
35
36
37   /*************************************************************************/
38   /*************************************************************************/
39   /****                                                                 ****/
40   /****   EXPERIMENTAL OBLIQUING SUPPORT                                ****/
41   /****                                                                 ****/
42   /*************************************************************************/
43   /*************************************************************************/
44
45   /* documentation is in ftsynth.h */
46
47   FT_EXPORT_DEF( void )
48   FT_GlyphSlot_Oblique( FT_GlyphSlot  slot )
49   {
50     FT_Matrix    transform;
51     FT_Outline*  outline = &slot->outline;
52
53
54     /* only oblique outline glyphs */
55     if ( slot->format != FT_GLYPH_FORMAT_OUTLINE )
56       return;
57
58     /* we don't touch the advance width */
59
60     /* For italic, simply apply a shear transform, with an angle */
61     /* of about 12 degrees.                                      */
62
63     transform.xx = 0x10000L;
64     transform.yx = 0x00000L;
65
66     transform.xy = 0x0366AL;
67     transform.yy = 0x10000L;
68
69     FT_Outline_Transform( outline, &transform );
70   }
71
72
73   /*************************************************************************/
74   /*************************************************************************/
75   /****                                                                 ****/
76   /****   EXPERIMENTAL EMBOLDENING SUPPORT                              ****/
77   /****                                                                 ****/
78   /*************************************************************************/
79   /*************************************************************************/
80
81
82   /* documentation is in ftsynth.h */
83
84   FT_EXPORT_DEF( void )
85   FT_GlyphSlot_Embolden( FT_GlyphSlot  slot )
86   {
87     FT_Library  library = slot->library;
88     FT_Face     face    = slot->face;
89     FT_Error    error;
90     FT_Pos      xstr, ystr;
91
92
93     if ( slot->format != FT_GLYPH_FORMAT_OUTLINE &&
94          slot->format != FT_GLYPH_FORMAT_BITMAP  )
95       return;
96
97     /* some reasonable strength */
98     xstr = FT_MulFix( face->units_per_EM,
99                       face->size->metrics.y_scale ) / 24;
100     ystr = xstr;
101
102     if ( slot->format == FT_GLYPH_FORMAT_OUTLINE )
103     {
104       /* ignore error */
105       (void)FT_Outline_EmboldenXY( &slot->outline, xstr, ystr );
106     }
107     else /* slot->format == FT_GLYPH_FORMAT_BITMAP */
108     {
109       /* round to full pixels */
110       xstr &= ~63;
111       if ( xstr == 0 )
112         xstr = 1 << 6;
113       ystr &= ~63;
114
115       /*
116        * XXX: overflow check for 16-bit system, for compatibility
117        *      with FT_GlyphSlot_Embolden() since freetype-2.1.10.
118        *      unfortunately, this function return no informations
119        *      about the cause of error.
120        */
121       if ( ( ystr >> 6 ) > FT_INT_MAX || ( ystr >> 6 ) < FT_INT_MIN )
122       {
123         FT_TRACE1(( "FT_GlyphSlot_Embolden:" ));
124         FT_TRACE1(( "too strong embolding parameter ystr=%d\n", ystr ));
125         return;
126       }
127       error = FT_GlyphSlot_Own_Bitmap( slot );
128       if ( error )
129         return;
130
131       error = FT_Bitmap_Embolden( library, &slot->bitmap, xstr, ystr );
132       if ( error )
133         return;
134     }
135
136     if ( slot->advance.x )
137       slot->advance.x += xstr;
138
139     if ( slot->advance.y )
140       slot->advance.y += ystr;
141
142     slot->metrics.width       += xstr;
143     slot->metrics.height      += ystr;
144     slot->metrics.horiAdvance += xstr;
145     slot->metrics.vertAdvance += ystr;
146
147     /* XXX: 16-bit overflow case must be excluded before here */
148     if ( slot->format == FT_GLYPH_FORMAT_BITMAP )
149       slot->bitmap_top += (FT_Int)( ystr >> 6 );
150   }
151
152
153 /* END */