summaryrefslogtreecommitdiffstats
path: root/src/formula.cpp
blob: 0a961ca64a6c96b0f03cbe7a23b377e9c69a0643 (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
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
/******************************************************************************
 *
 * $Id$
 *
 * Copyright (C) 1997-1999 by Dimitri van Heesch.
 *
 * Permission to use, copy, modify, and distribute this software and its
 * documentation under the terms of the GNU General Public License is hereby 
 * granted. No representations are made about the suitability of this software 
 * for any purpose. It is provided "as is" without express or implied warranty.
 * See the GNU General Public License for more details.
 *
 * All output generated with Doxygen is not covered by this license.
 *
 */

#include <stdlib.h>
#include <unistd.h>

#include "qtbc.h"
#include <qfile.h>
#include <qtstream.h>
#include <qfileinf.h>
#include <qdir.h>

#include "formula.h"
#include "image.h"
#include "util.h"
#include "message.h"

Formula::Formula(const char *text)
{
  static int count=0;
  number = count++;
  form=text;
}

Formula::~Formula()
{
}

int Formula::getId()
{
  return number;
}

void FormulaList::generateBitmaps(const char *path)
{
  int x1,y1,x2,y2;
  QDir d(path);
  // store the original directory
  if (!d.exists()) { err("Error: Output dir %s does not exist!\n",path); exit(1); }
  QCString oldDir = convertToQCString(QDir::currentDirPath());
  // goto the html output directory (i.e. path)
  QDir::setCurrent(d.absPath());
  QDir thisDir;
  // generate a latex file containing one formula per page.
  QCString texName="_formulas.tex";
  QList<int> pagesToGenerate;
  pagesToGenerate.setAutoDelete(TRUE);
  FormulaListIterator fli(*this);
  Formula *formula;
  QFile f(texName);
  if (f.open(IO_WriteOnly))
  {
    QTextStream t(&f);
    t << "\\documentclass{article}" << endl;
    t << "\\usepackage{epsf}" << endl; // for those who want to include images
    t << "\\pagestyle{empty}" << endl; 
    t << "\\begin{document}" << endl;
    int page=0;
    for (fli.toFirst();(formula=fli.current());++fli)
    {
      QCString resultName;
      resultName.sprintf("form-%d.gif",formula->getId());
      // only formulas for which no image exists are generated
      QFileInfo fi(resultName);
      if (!fi.exists())
      {
        // we force a pagebreak after each formula
        t << formula->getFormulaText() << endl << "\\pagebreak\n\n";
        pagesToGenerate.append(new int(page));
      }
      page++;
    }
    t << "\\end{document}" << endl;
    f.close();
  }
  if (pagesToGenerate.count()>0) // there are new formulas
  {
    //printf("Running latex...\n");
    //system("latex _formulas.tex </dev/null >/dev/null");
    system("latex _formulas.tex");
    //printf("Running dvips...\n");
    QListIterator<int> pli(pagesToGenerate);
    int *pagePtr;
    int pageIndex=1;
    for (;(pagePtr=pli.current());++pli,++pageIndex)
    {
      int pageNum=*pagePtr;
      msg("Generating image form-%d.gif for formula\n",pageNum);
      char dviCmd[256];
      QCString formBase;
      formBase.sprintf("_form%d",pageNum);
      // run dvips to convert the page with number pageIndex to an
      // encapsulated postscript.
      sprintf(dviCmd,"dvips -q -D 600 -E -n 1 -p %d -o %s.eps _formulas.dvi",
          pageIndex,formBase.data());
      system(dviCmd);
      // now we read the generated postscript file to extract the bounding box
      QFileInfo fi(formBase+".eps");
      if (fi.exists())
      {
        QCString eps = fileToString(formBase+".eps");
        int i=eps.find("%%BoundingBox:");
        if (i!=-1)
        {
          sscanf(eps.data()+i,"%%%%BoundingBox:%d %d %d %d",&x1,&y1,&x2,&y2);
        }
        else
        {
          err("Error: Couldn't extract bounding box!\n");
        }
      } 
      // next we generate a postscript file which contains the eps
      // and displays it in the right colors and the right bounding box
      f.setName(formBase+".ps");
      if (f.open(IO_WriteOnly))
      {
        QTextStream t(&f);
        t << "1 1 1 setrgbcolor" << endl;  // anti-alias to white background
        t << "newpath" << endl;
        t << "-1 -1 moveto" << endl;
        t << x2-x1+2 << " -1 lineto" << endl;
        t << x2-x1+2 << " " << y2-y1+2 << " lineto" << endl;
        t << "-1 " << y2-y1+2 << " lineto" <<endl;
        t << "closepath" << endl;
        t << "fill" << endl;
        t << -x1 << " " << -y1 << " translate" << endl;
        t << "0 0 0 setrgbcolor" << endl;
        t << "(" << formBase << ".eps) run" << endl;
        f.close();
      }
      // scale the image so that it is four times larger than needed.
      // and the sizes are a multiple of four.
      const double scaleFactor = 16.0/3.0; 
      int gx = (((int)((x2-x1)*scaleFactor))+3)&~2;
      int gy = (((int)((y2-y1)*scaleFactor))+3)&~2;
      char gsCmd[256];
      // Then we run ghostscript to convert the postscript to a pixmap
      // The pixmap is a truecolor image, where only black and white are
      // used.  
      sprintf(gsCmd,"gs -q -g%dx%d -r%dx%dx -sDEVICE=ppmraw "
                    "-sOutputFile=%s.pnm -DNOPAUSE -- %s.ps",
                    gx,gy,(int)(scaleFactor*72),(int)(scaleFactor*72),
                    formBase.data(),formBase.data()
             );
      //printf("Running ghostscript...\n");
      system(gsCmd);
      f.setName(formBase+".pnm");
      uint imageX=0,imageY=0;
      // we read the generated image again, to obtain the pixel data.
      if (f.open(IO_ReadOnly))
      {
        QTextStream t(&f);
        QCString s;
        if (!t.eof())
          s=t.readLine();
        if (s.length()<2 || s.left(2)!="P6")
          err("Error: ghostscript produced an illegal image format!");
        else
        {
          // assume the size if after the first line that does not start with
          // # excluding the first line of the file.
          while (!t.eof() && (s=t.readLine()) && !s.isEmpty() && s.at(0)=='#');
          sscanf(s,"%d %d",&imageX,&imageY);
        }
        if (imageX>0 && imageY>0)
        {
          //printf("Converting image...\n");
          char *data = new char[imageX*imageY*3]; // rgb 8:8:8 format
          uint i,x,y,ix,iy;
          f.readBlock(data,imageX*imageY*3);
          Image srcImage(imageX,imageY),
                filteredImage(imageX,imageY),
                dstImage(imageX/4,imageY/4);
          uchar *ps=srcImage.getData();
          // convert image to black (1) and white (0) index.
          for (i=0;i<imageX*imageY;i++) *ps++= (data[i*3]==0 ? 1 : 0);
          // apply a simple box filter to the image 
          static int filterMask[]={1,2,1,2,8,2,1,2,1};
          for (y=0;y<srcImage.getHeight();y++)
          {
            for (x=0;x<srcImage.getWidth();x++)
            {
              int s=0;
              for (iy=0;iy<2;iy++)
              {
                for (ix=0;ix<2;ix++)
                {
                  s+=srcImage.getPixel(x+ix-1,y+iy-1)*filterMask[iy*3+ix];
                }
              }
              filteredImage.setPixel(x,y,s);
            }
          }
          // down-sample the image to 1/16th of the area using 16 gray scale
          // colors.
          for (y=0;y<dstImage.getHeight();y++)
          {
            for (x=0;x<dstImage.getWidth();x++)
            {
              int xp=x<<2;
              int yp=y<<2;
              int c=filteredImage.getPixel(xp+0,yp+0)+
                    filteredImage.getPixel(xp+1,yp+0)+
                    filteredImage.getPixel(xp+2,yp+0)+
                    filteredImage.getPixel(xp+3,yp+0)+
                    filteredImage.getPixel(xp+0,yp+1)+
                    filteredImage.getPixel(xp+1,yp+1)+
                    filteredImage.getPixel(xp+2,yp+1)+
                    filteredImage.getPixel(xp+3,yp+1)+
                    filteredImage.getPixel(xp+0,yp+2)+
                    filteredImage.getPixel(xp+1,yp+2)+
                    filteredImage.getPixel(xp+2,yp+2)+
                    filteredImage.getPixel(xp+3,yp+2)+
                    filteredImage.getPixel(xp+0,yp+3)+
                    filteredImage.getPixel(xp+1,yp+3)+
                    filteredImage.getPixel(xp+2,yp+3)+
                    filteredImage.getPixel(xp+3,yp+3);
              // here we scale and clip the color value so the
              // resulting image has a reasonable contrast
              dstImage.setPixel(x,y,QMIN(15,(c*15)/(16*10)));
            }
          }
          // save the result as a gif
          QCString resultName;
          resultName.sprintf("form-%d.gif",pageNum);
          // the option parameter 1 is used here as a temporary hack
          // to select the right color palette! 
          dstImage.save(resultName,1);
          delete[] data;
        }
        f.close();
      } 
      // remove intermediate image files
      thisDir.remove(formBase+".eps");
      thisDir.remove(formBase+".pnm");
      thisDir.remove(formBase+".ps");
    }
    // remove intermediate files produced by latex
    thisDir.remove("_formulas.dvi");
    thisDir.remove("_formulas.log");
    thisDir.remove("_formulas.aux");
  }
  // remove the latex file itself
  thisDir.remove("_formulas.tex");
  // write/update the formula repository so we know what text the 
  // generated gifs represent (we use this next time to avoid regeneration
  // of the gifs, and to avoid forcing the user to delete all gifs in order
  // to let a browser refresh the images).
  f.setName("formula.repository");
  if (f.open(IO_WriteOnly))
  {
    QTextStream t(&f);
    for (fli.toFirst();(formula=fli.current());++fli)
    {
      t << "\\form#" << formula->getId() << ":" << formula->getFormulaText() << endl;
    }
    f.close();
  }
  // reset the directory to the original location.
  QDir::setCurrent(oldDir);
}


#ifdef FORMULA_TEST
int main()
{
  FormulaList fl;
  fl.append(new Formula("$x^2$"));
  fl.append(new Formula("$y^2$"));
  fl.append(new Formula("$\\sqrt{x_0^2+x_1^2+x_2^2}$"));
  fl.generateBitmaps("dest");
  return 0;
}
#endif