app/diapsft2renderer.c

   1 /* Dia -- an diagram creation/manipulation program
   2  * Copyright (C) 1998 Alexander Larsson
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation; either version 2 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  17  */
  18
  19 #include <config.h>
  20
  21 #include <string.h>
  22
  23 #include "font.h"
  24
  25 #include "diapsft2renderer.h"
  26
  27 #include <pango/pango.h>
  28 #include <pango/pangoft2.h>
  29 /* I'd really rather avoid this */
  30 #include <freetype/ftglyph.h>
  31 #include <freetype/ftoutln.h>
  32
  33 #define DPI 300
  34
  35 /* These routines stolen mercilessly from PAPS
  36  * http://imagic.weizmann.ac.il/~dov/freesw/paps
  37  */
  38 /* Information passed in user data when drawing outlines */
  39 typedef struct _OutlineInfo OutlineInfo;
  40 struct _OutlineInfo {
  41   FILE *OUT;
  42   FT_Vector glyph_origin;
  43   int dpi;
  44 };
  45
  46 void postscript_contour_headers(FILE *OUT, int dpi_x, int dpi_y);
  47 void postscript_draw_contour(DiaPsRenderer *renderer,
  48                              int dpi_x,
  49                              PangoLayoutLine *pango_line,
  50                              double x_pos,
  51                              double y_pos
  52                              );
  53 void draw_bezier_outline(DiaPsRenderer *renderer,
  54                          int dpi_x,
  55                          FT_Face face,
  56                          FT_UInt glyph_index,
  57                          double pos_x,
  58                          double pos_y
  59                          );
  60 /* Countour traveling functions */
  61 static int paps_move_to( FT_Vector* to,
  62                          void *user_data);
  63 static int paps_line_to( FT_Vector*  to,
  64                          void *user_data);
  65 static int paps_conic_to( FT_Vector*  control,
  66                           FT_Vector*  to,
  67                           void *user_data);
  68 static int paps_cubic_to( FT_Vector*  control1,
  69                           FT_Vector*  control2,
  70                           FT_Vector*  to,
  71                           void *user_data);
  72
  73 static void dia_ps_ft2_renderer_class_init (DiaPsFt2RendererClass *klass);
  74
  75 static gpointer parent_class = NULL;
  76
  77 static void
  78 set_font(DiaRenderer *self, DiaFont *font, real height)
  79 {
  80   DiaPsFt2Renderer *renderer = DIA_PS_FT2_RENDERER(self);
  81
  82   renderer->current_font = font;
  83   /* Dammit!  We have a random factor once again! */
  84   renderer->current_height = height*4.3;
  85   pango_context_set_font_description(dia_font_get_context(), font->pfd);
  86 }
  87
  88 /* ********************************************************* */
  89 /*                 String rendering using PangoFt2           */
  90 /* ********************************************************* */
  91 /* Such a big mark really is a sign that this should go in its own file:) */
  92 /* And so it did. */
  93
  94 /*======================================================================
  95   outline traversing functions.
  96   ----------------------------------------------------------------------*/
  97 static int paps_move_to( FT_Vector* to,
  98                          void *user_data)
  99 {
 100   OutlineInfo *outline_info = (OutlineInfo*)user_data;
 101   fprintf(outline_info->OUT, "%d %d moveto\n",
 102           to->x ,
 103           to->y );
 104   return 0;
 105 }
 106
 107 static int paps_line_to( FT_Vector*  to,
 108                          void *user_data)
 109 {
 110   OutlineInfo *outline_info = (OutlineInfo*)user_data;
 111   fprintf(outline_info->OUT, "%d %d lineto\n",
 112           to->x ,
 113           to->y );
 114   return 0;
 115 }
 116
 117 static int paps_conic_to( FT_Vector*  control,
 118                           FT_Vector*  to,
 119                           void *user_data)
 120 {
 121   OutlineInfo *outline_info = (OutlineInfo*)user_data;
 122   fprintf(outline_info->OUT, "%d %d %d %d conicto\n",
 123           control->x  ,
 124           control->y  ,
 125           to->x   ,
 126           to->y  );
 127   return 0;
 128 }
 129
 130 static int paps_cubic_to( FT_Vector*  control1,
 131                           FT_Vector*  control2,
 132                           FT_Vector*  to,
 133                           void *user_data)
 134 {
 135   OutlineInfo *outline_info = (OutlineInfo*)user_data;
 136   fprintf(outline_info->OUT,
 137           "%d %d %d %d %d %d curveto\n",
 138           control1->x ,
 139           control1->y ,
 140           control2->x ,
 141           control2->y ,
 142           to->x ,
 143           to->y );
 144   return 0;
 145 }
 146
 147 /* These must go in the prologue section */
 148 void postscript_contour_headers(FILE *OUT, int dpi_x, int dpi_y)
 149 {
 150   /* /dpi_x needed for /conicto */
 151   fprintf(OUT,
 152           "/dpi_x %d def\n"
 153           "/dpi_y %d def\n", dpi_x, dpi_y);
 154   /* Outline support */
 155   fprintf(OUT,
 156           "/conicto {\n"
 157           "    /to_y exch def\n"
 158           "    /to_x exch def\n"
 159           "    /conic_cntrl_y exch def\n"
 160           "    /conic_cntrl_x exch def\n"
 161           "    currentpoint\n"
 162           "    /p0_y exch def\n"
 163           "    /p0_x exch def\n"
 164           "    /p1_x p0_x conic_cntrl_x p0_x sub 2 3 div mul add def\n"
 165           "    /p1_y p0_y conic_cntrl_y p0_y sub 2 3 div mul add def\n"
 166           "    /p2_x p1_x to_x p0_x sub 1 3 div mul add def\n"
 167           "    /p2_y p1_y to_y p0_y sub 1 3 div mul add def\n"
 168           "    p1_x p1_y p2_x p2_y to_x to_y curveto\n"
 169           "} bind def\n"
 170           "/start_ol { gsave 1.1 dpi_x div dup scale} bind def\n"
 171           "/end_ol { closepath fill grestore } bind def\n"
 172           );
 173 }
 174
 175
 176 /* postscript_draw_contour() dumps out the information of a line. It shows how
 177    to access the ft font information out of the pango font info.
 178 */
 179 void postscript_draw_contour(DiaPsRenderer *renderer,
 180                              int dpi_x,
 181                              PangoLayoutLine *pango_line,
 182                              double line_start_pos_x,
 183                              double line_start_pos_y)
 184 {
 185   GSList *runs_list;
 186   int num_runs = 0;
 187   PangoRectangle ink_rect, logical_rect;
 188   int byte_width;
 189   FT_Bitmap bitmap;
 190   guchar *buf;
 191
 192   /* First calculate number of runs in text */
 193   runs_list = pango_line->runs;
 194   while(runs_list)
 195   {
 196     PangoLayoutRun *run = runs_list->data;
 197     num_runs++;
 198     runs_list = runs_list->next;
 199   }
 200   /* Loop over the runs and output font info */
 201   runs_list = pango_line->runs;
 202   while(runs_list)
 203   {
 204     PangoLayoutRun *run = runs_list->data;
 205     PangoItem *item = run->item;
 206     PangoGlyphString *glyphs = run->glyphs;
 207     PangoAnalysis *analysis = &item->analysis;
 208     PangoFont *font = analysis->font;
 209     /*
 210       PangoFont *font = pango_context_load_font(renderer->context,
 211       renderer->current_font->pfd);
 212     */
 213     FT_Face ft_face;
 214     int bidi_level;
 215     int num_glyphs;
 216     int glyph_idx;
 217
 218     if (font == NULL) {
 219       fprintf(stderr, "No font found\n");
 220       continue;
 221     }
 222     ft_face = pango_ft2_font_get_face(font);
 223     if (ft_face == NULL) {
 224       fprintf(stderr, "Failed to get face for font %s\n",
 225               pango_font_description_to_string(pango_font_describe(font)));
 226       continue;
 227     }
 228
 229     /*
 230       printf("Got face %s (PS %s) for font %s (diafont %s)\n",
 231       ft_face->family_name,
 232       FT_Get_Postscript_Name(ft_face),
 233       pango_font_description_to_string(pango_font_describe(font)),
 234       dia_font_get_family(renderer->current_font));
 235     */
 236
 237     bidi_level = item->analysis.level;
 238     num_glyphs = glyphs->num_glyphs;
 239
 240     for (glyph_idx=0; glyph_idx<num_glyphs; glyph_idx++)
 241     {
 242       PangoGlyphGeometry geometry = glyphs->glyphs[glyph_idx].geometry;
 243       double pos_x;
 244       double pos_y;
 245       double scale = 2.54/PANGO_SCALE/dpi_x;/*72.0 / PANGO_SCALE  / dpi_x;*/
 246
 247       pos_x = line_start_pos_x + 1.0* geometry.x_offset * scale;
 248       pos_y = line_start_pos_y - 1.0*geometry.y_offset * scale;
 249
 250       line_start_pos_x += 1.0 * geometry.width * scale;
 251
 252       /*
 253         printf("Drawing glyph %d: index %d at %f, %f (w %d)\n", glyph_idx,
 254         glyphs->glyphs[glyph_idx].glyph, pos_x, pos_y,
 255         geometry.width);
 256       */
 257       draw_bezier_outline(renderer,
 258                           dpi_x,
 259                           ft_face,
 260                           (FT_UInt)(glyphs->glyphs[glyph_idx].glyph),
 261                           pos_x, pos_y
 262                           );
 263     }
 264
 265     runs_list = runs_list->next;
 266   }
 267
 268 }
 269
 270 void draw_bezier_outline(DiaPsRenderer *renderer,
 271                          int dpi_x,
 272                          FT_Face face,
 273                          FT_UInt glyph_index,
 274                          double pos_x,
 275                          double pos_y
 276                          )
 277 {
 278   FT_Int load_flags = FT_LOAD_DEFAULT|FT_LOAD_NO_BITMAP;
 279   FT_Glyph glyph;
 280   FT_Error error;
 281
 282   /* Need to transform */
 283
 284   /* Output outline */
 285   FT_Outline_Funcs outlinefunc =
 286     {
 287       paps_move_to,
 288       paps_line_to,
 289       paps_conic_to,
 290       paps_cubic_to
 291     };
 292   OutlineInfo outline_info;
 293
 294   outline_info.glyph_origin.x = pos_x;
 295   outline_info.glyph_origin.y = pos_y;
 296   outline_info.dpi = dpi_x;
 297   outline_info.OUT = renderer->file;
 298
 299   fprintf(renderer->file,
 300           "gsave %f %f translate %f %f scale\n",
 301           pos_x, pos_y, 2.54/72.0, -2.54/72.0);
 302   fprintf(renderer->file, "start_ol\n");
 303
 304   if ((error=FT_Load_Glyph(face, glyph_index, load_flags))) {
 305     fprintf(stderr, "Can't load glyph: %d\n", error);
 306     return;
 307   }
 308   FT_Get_Glyph (face->glyph, &glyph);
 309   FT_Outline_Decompose (&(((FT_OutlineGlyph)glyph)->outline),
 310                         &outlinefunc, &outline_info);
 311   fprintf(renderer->file, "end_ol grestore \n");
 312
 313   FT_Done_Glyph (glyph);
 314 }
 315
 316 static void
 317 draw_string(DiaRenderer *self,
 318             const char *text,
 319             Point *pos, Alignment alignment,
 320             Color *color)
 321 {
 322   //DiaPsRenderer *renderer = DIA_PS_RENDERER(self);
 323   DiaPsFt2Renderer *renderer = DIA_PS_FT2_RENDERER(self);
 324   PangoLayout *layout;
 325   int width;
 326   int line, linecount;
 327   double xpos = pos->x, ypos = pos->y;
 328   PangoAttrList* list;
 329   PangoAttribute* attr;
 330   guint length;
 331
 332   if ((!text)||(text == (const char *)(1))) return;
 333
 334   lazy_setcolor(DIA_PS_RENDERER(renderer),color);
 335
 336   /* Make sure the letters aren't too wide. */
 337   layout = dia_font_scaled_build_layout(text, renderer->current_font,
 338                                         renderer->current_height/0.7,
 339                                         20.0);
 340   /*
 341   dia_font_set_height(renderer->current_font, renderer->current_height);
 342   layout = pango_layout_new(dia_font_get_context());
 343
 344   length = text ? strlen(text) : 0;
 345   pango_layout_set_text(layout,text,length);
 346
 347   list = pango_attr_list_new();
 348
 349   attr = pango_attr_font_desc_new(renderer->current_font->pfd);
 350   attr->start_index = 0;
 351   attr->end_index = length;
 352   pango_attr_list_insert(list,attr);
 353
 354   pango_layout_set_attributes(layout,list);
 355   pango_attr_list_unref(list);
 356
 357   pango_layout_set_indent(layout,0);
 358   pango_layout_set_justify(layout,FALSE);
 359   */
 360   switch (alignment) {
 361   case ALIGN_LEFT:
 362     pango_layout_set_alignment(layout,PANGO_ALIGN_LEFT);
 363     break;
 364   case ALIGN_CENTER:
 365     pango_layout_set_alignment(layout,PANGO_ALIGN_CENTER);
 366     break;
 367   case ALIGN_RIGHT:
 368     pango_layout_set_alignment(layout,PANGO_ALIGN_RIGHT);
 369     break;
 370   }
 371
 372   pango_layout_get_size(layout, &width, NULL);
 373   linecount = pango_layout_get_line_count(layout);
 374   for (line = 0; line < linecount; line++) {
 375     PangoLayoutLine *layoutline = pango_layout_get_line(layout, line);
 376     real width, xoff = 0.0;
 377     PangoRectangle rectangle;
 378
 379     pango_layout_line_get_extents(layoutline, &rectangle, NULL);
 380     width = rectangle.width;
 381
 382     switch (alignment) {
 383     case ALIGN_LEFT:
 384       xoff = 0.0;
 385       break;
 386     case ALIGN_CENTER:
 387       xoff = width/2.0;
 388       break;
 389     case ALIGN_RIGHT:
 390       xoff = width;
 391       break;
 392     }
 393     xoff *= 2.54/PANGO_SCALE/DPI /* dpi_x */;
 394
 395     postscript_draw_contour(DIA_PS_RENDERER(renderer),
 396                             DPI, /* dpi_x */
 397                             layoutline,
 398                             xpos-xoff, ypos);
 399     /* xpos should be adjusted for align and/or RTL */
 400     ypos += 10;/* Some line height thing??? */
 401   }
 402 }
 403
 404 static void
 405 dump_fonts (DiaPsRenderer *renderer)
 406 {
 407   postscript_contour_headers(renderer->file, DPI, DPI);
 408 }
 409
 410 GType
 411 dia_ps_ft2_renderer_get_type (void)
 412 {
 413   static GType object_type = 0;
 414
 415   if (!object_type)
 416     {
 417       static const GTypeInfo object_info =
 418       {
 419         sizeof (DiaPsFt2RendererClass),
 420         (GBaseInitFunc) NULL,
 421         (GBaseFinalizeFunc) NULL,
 422         (GClassInitFunc) dia_ps_ft2_renderer_class_init,
 423         NULL,           /* class_finalize */
 424         NULL,           /* class_data */
 425         sizeof (DiaPsFt2Renderer),
 426         0,              /* n_preallocs */
 427         NULL            /* init */
 428       };
 429
 430       object_type = g_type_register_static (DIA_TYPE_PS_RENDERER,
 431                                             "DiaPsFt2Renderer",
 432                                             &object_info, 0);
 433     }
 434
 435   return object_type;
 436 }
 437
 438 static void
 439 dia_ps_ft2_renderer_finalize (GObject *object)
 440 {
 441   DiaPsFt2Renderer *dia_ps_ft2_renderer = DIA_PS_FT2_RENDERER (object);
 442
 443   G_OBJECT_CLASS (parent_class)->finalize (object);
 444 }
 445
 446 static void
 447 dia_ps_ft2_renderer_class_init (DiaPsFt2RendererClass *klass)
 448 {
 449   GObjectClass *object_class = G_OBJECT_CLASS (klass);
 450   DiaRendererClass *renderer_class = DIA_RENDERER_CLASS (klass);
 451   DiaPsRendererClass *ps_renderer_class = DIA_PS_RENDERER_CLASS (klass);
 452
 453   parent_class = g_type_class_peek_parent (klass);
 454
 455   object_class->finalize = dia_ps_ft2_renderer_finalize;
 456
 457   renderer_class->set_font     = set_font;
 458   renderer_class->draw_string  = draw_string;
 459
 460   /* ps specific */
 461   ps_renderer_class->dump_fonts   = dump_fonts;
 462 }