summaryrefslogtreecommitdiff
path: root/Build/source/texk/dvipng/t1.c
blob: 84a15a5bf6768f06863650a85e2c0c8fe20286d5 (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
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
/* t1.c */

/************************************************************************

  Part of the dvipng distribution

  This program is free software: you can redistribute it and/or modify
  it under the terms of the GNU Lesser General Public License as
  published by the Free Software Foundation, either version 3 of the
  License, or (at your option) any later version.

  This program is distributed in the hope that it will be useful, but
  WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  Lesser General Public License for more details.

  You should have received a copy of the GNU Lesser General Public
  License along with this program. If not, see
  <http://www.gnu.org/licenses/>.

  Copyright (C) 2002-2008 Jan-Åke Larsson

************************************************************************/

#include "dvipng.h"
#ifdef HAVE_ALLOCA_H
# include <alloca.h>
#endif

void LoadT1(int32_t c, struct char_entry * ptr)
{
  GLYPH *glyph;
  int original_width,original_height;
  int i,j,k,width,height;
  unsigned short   shrunk_width,shrunk_height;
  short   xoffset,yoffset;
  unsigned short   i_offset,j_offset;

  DEBUG_PRINT(DEBUG_T1,("\n  LOAD T1 CHAR\t%d",c));
  if ((glyph=
       T1_SetChar(currentfont->T1id, c,
		  (float)currentfont->dpi*currentfont->d/65536/72.27,
		  currentfont->psfontmap==NULL ? NULL : currentfont->psfontmap->t1_transformp))
      ==NULL)
      Fatal("cannot load T1 char %d",c);

  DEBUG_PRINT(DEBUG_T1,(" (%d)",ptr->tfmw));
  
  original_width = glyph->metrics.rightSideBearing 
    - glyph->metrics.leftSideBearing;
  original_height  = glyph->metrics.ascent - glyph->metrics.descent;
  DEBUG_PRINT(DEBUG_T1,(" %dx%d",original_width,original_height));

  if (original_width > 0x7fff || original_height > 0x7fff)
    Fatal("character %d too large in file %s", c, currentfont->name);

  /* 
   * Hotspot issues: Shrinking to the topleft corner rather than the
     hotspot will displace glyphs a fraction of a pixel. We deal with
     this in as follows: The glyph is shrunk to its hotspot by
     offsetting the bitmap somewhat to put the hotspot in the lower
     left corner of a "shrink square". Shrinking to the topleft corner
     will then act as shrinking to the hotspot. This may enlarge the
     bitmap somewhat, of course.  (Also remember that the below
     calculation of i/j_offset is in integer arithmetics.)
     
     There will still be a displacement from rounding the dvi
     position, but vertically it will be equal for all glyphs on a
     line, so we displace a whole line vertically by fractions of a
     pixel. This is acceptible, IMHO. Sometime there will be support
     for subpixel positioning, horizontally. Will do for now, I
     suppose.
   */
  xoffset = -glyph->metrics.leftSideBearing;
  /* printf("xoffset: %d\n",xoffset); */
  i_offset = ( shrinkfactor - xoffset % shrinkfactor ) % shrinkfactor;
  width = original_width+i_offset;
  ptr->xOffset = xoffset+i_offset;

  yoffset = glyph->metrics.ascent-1;
  /* printf("yoffset: %d\n",yoffset); */
  j_offset = ( shrinkfactor - (yoffset-(shrinkfactor-1)) % shrinkfactor )
    % shrinkfactor;
  height = original_height+j_offset;
  ptr->yOffset = yoffset+j_offset;

  DEBUG_PRINT(DEBUG_T1,(" (%dx%d)",width,height));
  /* 
     Extra marginal so that we do not crop the image when shrinking.
  */
  shrunk_width = (width + shrinkfactor - 1) / shrinkfactor;
  shrunk_height = (height + shrinkfactor - 1) / shrinkfactor;
  ptr->w = shrunk_width;
  ptr->h = shrunk_height;

  /* printf("(%d,%d) ",ptr->w,ptr->h); */
  DEBUG_PRINT(DEBUG_GLYPH,("\nDRAW GLYPH %d\n", (int)c));

  /*
    Shrink raster while doing antialiasing. 
  */
  if ((ptr->data = calloc(shrunk_width*shrunk_height,sizeof(char))) == NULL)
    Fatal("unable to allocate image space for char %c", (char)c);
  for (j = 0; j < original_height; j++) {	
    for (i = 0; i < (original_width+7)/8 ; i++) {    
      for (k = 0; k < 8 ; k++) {
	DEBUG_PRINT(DEBUG_GLYPH,
		    ("%c",
		     (glyph->bits[i+j*((original_width+7)/8)] & (1<<k)) ?
		      'x' : ' '));
	ptr->data[(i*8+k+i_offset)/shrinkfactor
		  +(j+j_offset)/shrinkfactor*shrunk_width] += 
	  (glyph->bits[i+j*((original_width+7)/8)] & (1<<k) ? 1 : 0);
      }
    }    
    DEBUG_PRINT(DEBUG_GLYPH,("|\n"));
  }	
  for (j = 0; j < shrunk_height; j++) {	
    for (i = 0; i < shrunk_width; i++) {    
      ptr->data[i+j*shrunk_width] = ptr->data[i+j*shrunk_width]
	*255/shrinkfactor/shrinkfactor;
      DEBUG_PRINT(DEBUG_GLYPH,("%3u ",ptr->data[i+j*shrunk_width]));
    }
    DEBUG_PRINT(DEBUG_GLYPH,("|\n"));
  }	 
}

bool InitT1(struct font_entry * tfontp)
{
  if (libt1==NULL) {
    if ((libt1=T1_InitLib( NO_LOGFILE | IGNORE_CONFIGFILE
			   | IGNORE_FONTDATABASE | T1_NO_AFM)) == NULL) {
      Warning("an error occured during t1lib initialisation, disabling it"); 
      option_flags &= ~USE_LIBT1;
      return(false);
    }
# ifdef DEBUG
    else 
      DEBUG_PRINT(DEBUG_T1,("\n  T1LIB VERSION: %s", T1_GetLibIdent()));
# endif
  }

  DEBUG_PRINT((DEBUG_DVI|DEBUG_T1),("\n  OPEN T1 FONT:\t'%s'", tfontp->name));
  tfontp->T1id = T1_AddFont( tfontp->name );
  if (tfontp->T1id < 0) {
    Warning("t1lib could not open font file %s", tfontp->name);
    return(false);
  } 
  if (T1_LoadFont(tfontp->T1id)) {
    Warning("t1lib could not load font file %s", tfontp->name);
    return(false);
  } 
  Message(BE_VERBOSE,"<%s>", tfontp->name);
  if (tfontp->psfontmap!=NULL && tfontp->psfontmap->encoding != NULL) {
    DEBUG_PRINT(DEBUG_T1,("\n  USE ENCODING:\t'%s'", tfontp->psfontmap->encoding->name));
    if (T1_ReencodeFont(tfontp->T1id,tfontp->psfontmap->encoding->charname)) {
      Warning("unable to use font encoding '%s' for %s", 
	      tfontp->psfontmap->encoding->name,tfontp->name);
      return(false);
    }
  }
  tfontp->type = FONT_TYPE_T1;
  return(true);
}


static void UnLoadT1(struct char_entry *ptr)
{
  if (ptr->data!=NULL)
    free(ptr->data);
  ptr->data=NULL;
}


void DoneT1(struct font_entry *tfontp)
{
  int c=0;

  int error = T1_DeleteFont( tfontp->T1id );
  if (error)
    Warning("font file %s could not be closed", tfontp->name);
  while(c<NFNTCHARS) {
    if (tfontp->chr[c]!=NULL) {
      UnLoadT1((struct char_entry*)tfontp->chr[c]);
      free(tfontp->chr[c]);
      tfontp->chr[c]=NULL;
    }
    c++;
  }
  tfontp->name[0]='\0';
}