src/mesa/drivers/x11/xfonts.c

   1 /* $Id: xfonts.c,v 1.6 2000/04/19 01:44:02 brianp Exp $ */
   2
   3 /*
   4  * Mesa 3-D graphics library
   5  * Version:  3.3
   6  *
   7  * Copyright (C) 1999-2000  Brian Paul   All Rights Reserved.
   8  *
   9  * Permission is hereby granted, free of charge, to any person obtaining a
  10  * copy of this software and associated documentation files (the "Software"),
  11  * to deal in the Software without restriction, including without limitation
  12  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  13  * and/or sell copies of the Software, and to permit persons to whom the
  14  * Software is furnished to do so, subject to the following conditions:
  15  *
  16  * The above copyright notice and this permission notice shall be included
  17  * in all copies or substantial portions of the Software.
  18  *
  19  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  20  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  21  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  22  * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
  23  * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  24  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  25  */
  26
  27
  28 /* xfonts.c -- glXUseXFont() for Mesa written by
  29  * Copyright (C) 1995 Thorsten.Ohl @ Physik.TH-Darmstadt.de
  30  */
  31
  32
  33 #ifdef HAVE_CONFIG_H
  34 #include "conf.h"
  35 #endif
  36
  37 #include <stdio.h>
  38 #include <stdlib.h>
  39 #include <string.h>
  40 #include <X11/Xlib.h>
  41 #include <X11/Xutil.h>
  42 #include "GL/gl.h"
  43 #include "GL/glx.h"
  44 #include "GL/xmesa.h"
  45 #include "context.h"
  46 #include "mem.h"
  47 #include "xfonts.h"
  48 #include "xmesaP.h"
  49
  50
  51 /* Some debugging info.  */
  52
  53 #ifdef DEBUG
  54 #undef _R
  55 #undef _G
  56 #undef _B
  57 #include <ctype.h>
  58
  59 int debug_xfonts = 0;
  60
  61 static void
  62 dump_char_struct (XCharStruct *ch, char *prefix)
  63 {
  64   printf ("%slbearing = %d, rbearing = %d, width = %d\n",
  65           prefix, ch->lbearing, ch->rbearing, ch->width);
  66   printf ("%sascent = %d, descent = %d, attributes = %u\n",
  67           prefix, ch->ascent, ch->descent, (unsigned int) ch->attributes);
  68 }
  69
  70 static void
  71 dump_font_struct (XFontStruct *font)
  72 {
  73   printf ("ascent = %d, descent = %d\n", font->ascent, font->descent);
  74   printf ("char_or_byte2 = (%u,%u)\n",
  75           font->min_char_or_byte2, font->max_char_or_byte2);
  76   printf ("byte1 = (%u,%u)\n", font->min_byte1, font->max_byte1);
  77   printf ("all_chars_exist = %s\n", font->all_chars_exist ? "True" :
  78 "False");
  79   printf ("default_char = %c (\\%03o)\n",
  80           (char) (isprint (font->default_char) ? font->default_char : ' '),
  81           font->default_char);
  82   dump_char_struct (&font->min_bounds, "min> ");
  83   dump_char_struct (&font->max_bounds, "max> ");
  84 #if 0
  85   for (c = font->min_char_or_byte2; c <= font->max_char_or_byte2; c++)
  86     {
  87       char prefix[8];
  88       sprintf (prefix, "%d> ", c);
  89       dump_char_struct (&font->per_char[c], prefix);
  90     }
  91 #endif
  92 }
  93
  94 static void
  95 dump_bitmap (unsigned int width, unsigned int height, GLubyte *bitmap)
  96 {
  97   unsigned int x, y;
  98
  99   printf ("    ");
 100   for (x = 0; x < 8*width; x++)
 101     printf ("%o", 7 - (x % 8));
 102   putchar ('\n');
 103   for (y = 0; y < height; y++)
 104     {
 105       printf ("%3o:", y);
 106       for (x = 0; x < 8*width; x++)
 107         putchar ((bitmap[width*(height - y - 1) + x/8] & (1 << (7 - (x %
 108 8))))
 109                  ? '*' : '.');
 110       printf ("   ");
 111       for (x = 0; x < width; x++)
 112         printf ("0x%02x, ", bitmap[width*(height - y - 1) + x]);
 113       putchar ('\n');
 114     }
 115 }
 116 #endif /* DEBUG */
 117
 118
 119 /* Implementation.  */
 120
 121 /* Fill a BITMAP with a character C from thew current font
 122    in the graphics context GC.  WIDTH is the width in bytes
 123    and HEIGHT is the height in bits.
 124
 125    Note that the generated bitmaps must be used with
 126
 127         glPixelStorei (GL_UNPACK_SWAP_BYTES, GL_FALSE);
 128         glPixelStorei (GL_UNPACK_LSB_FIRST, GL_FALSE);
 129         glPixelStorei (GL_UNPACK_ROW_LENGTH, 0);
 130         glPixelStorei (GL_UNPACK_SKIP_ROWS, 0);
 131         glPixelStorei (GL_UNPACK_SKIP_PIXELS, 0);
 132         glPixelStorei (GL_UNPACK_ALIGNMENT, 1);
 133
 134    Possible optimizations:
 135
 136      * use only one reusable pixmap with the maximum dimensions.
 137      * draw the entire font into a single pixmap (careful with
 138        proportional fonts!).
 139 */
 140
 141
 142 /*
 143  * Generate OpenGL-compatible bitmap.
 144  */
 145 static void
 146 fill_bitmap (Display *dpy, Window win, GC gc,
 147              unsigned int width, unsigned int height,
 148              int x0, int y0, unsigned int c, GLubyte *bitmap)
 149 {
 150   XImage *image;
 151   unsigned int x, y;
 152   Pixmap pixmap;
 153   XChar2b char2b;
 154
 155   pixmap = XCreatePixmap (dpy, win, 8*width, height, 1);
 156   XSetForeground(dpy, gc, 0);
 157   XFillRectangle (dpy, pixmap, gc, 0, 0, 8*width, height);
 158   XSetForeground(dpy, gc, 1);
 159
 160   char2b.byte1 = (c >> 8) & 0xff;
 161   char2b.byte2 = (c & 0xff);
 162
 163   XDrawString16 (dpy, pixmap, gc, x0, y0, &char2b, 1);
 164
 165   image = XGetImage (dpy, pixmap, 0, 0, 8*width, height, 1, XYPixmap);
 166   if (image) {
 167     /* Fill the bitmap (X11 and OpenGL are upside down wrt each other).  */
 168     for (y = 0; y < height; y++)
 169       for (x = 0; x < 8*width; x++)
 170         if (XGetPixel (image, x, y))
 171           bitmap[width*(height - y - 1) + x/8] |= (1 << (7 - (x % 8)));
 172     XDestroyImage (image);
 173   }
 174
 175   XFreePixmap (dpy, pixmap);
 176 }
 177
 178 /*
 179  * determine if a given glyph is valid and return the
 180  * corresponding XCharStruct.
 181  */
 182 static XCharStruct *isvalid(XFontStruct *fs, int which)
 183 {
 184   unsigned int  rows,pages;
 185   int           byte1,byte2;
 186   int           i,valid = 1;
 187
 188   rows = fs->max_byte1 - fs->min_byte1 + 1;
 189   pages = fs->max_char_or_byte2 - fs->min_char_or_byte2 + 1;
 190
 191   if (rows == 1) {
 192     /* "linear" fonts */
 193     if ((fs->min_char_or_byte2 > which) ||
 194         (fs->max_char_or_byte2 < which)) valid = 0;
 195   } else {
 196     /* "matrix" fonts */
 197     byte2 = which & 0xff;
 198     byte1 = which >> 8;
 199     if ((fs->min_char_or_byte2 > byte2) ||
 200         (fs->max_char_or_byte2 < byte2) ||
 201         (fs->min_byte1 > byte1) ||
 202         (fs->max_byte1 < byte1)) valid = 0;
 203   }
 204
 205   if (valid) {
 206     if (fs->per_char) {
 207       if (rows == 1) {
 208         /* "linear" fonts */
 209         return(fs->per_char + (which-fs->min_char_or_byte2) );
 210       } else {
 211         /* "matrix" fonts */
 212         i = ((byte1 - fs->min_byte1) * pages) +
 213              (byte2 - fs->min_char_or_byte2);
 214         return(fs->per_char + i);
 215       }
 216     } else {
 217         return(&fs->min_bounds);
 218     }
 219   }
 220   return(NULL);
 221 }
 222
 223
 224 void Fake_glXUseXFont( Font font, int first, int count, int listbase )
 225 {
 226   XMesaContext CC;
 227   Display *dpy;
 228   Window win;
 229   Pixmap pixmap;
 230   GC gc;
 231   XGCValues values;
 232   unsigned long valuemask;
 233   XFontStruct *fs;
 234
 235   GLint swapbytes, lsbfirst, rowlength;
 236   GLint skiprows, skippixels, alignment;
 237
 238   unsigned int max_width, max_height, max_bm_width, max_bm_height;
 239   GLubyte *bm;
 240
 241   int i;
 242
 243   CC = XMesaGetCurrentContext();
 244   dpy = CC->display;
 245   win = CC->xm_buffer->frontbuffer;
 246
 247   fs = XQueryFont (dpy, font);
 248   if (!fs)
 249     {
 250       gl_error (CC->gl_ctx, GL_INVALID_VALUE,
 251                 "Couldn't get font structure information");
 252       return;
 253     }
 254
 255   /* Allocate a bitmap that can fit all characters.  */
 256   max_width = fs->max_bounds.rbearing - fs->min_bounds.lbearing;
 257   max_height = fs->max_bounds.ascent + fs->max_bounds.descent;
 258   max_bm_width = (max_width + 7) / 8;
 259   max_bm_height = max_height;
 260
 261   bm = (GLubyte *) MALLOC((max_bm_width * max_bm_height) * sizeof
 262 (GLubyte));
 263   if (!bm) {
 264       XFreeFontInfo( NULL, fs, 0 );
 265       gl_error (CC->gl_ctx, GL_OUT_OF_MEMORY,
 266                 "Couldn't allocate bitmap in glXUseXFont()");
 267       return;
 268     }
 269
 270 #if 0
 271   /* get the page info */
 272   pages = fs->max_char_or_byte2 - fs->min_char_or_byte2 + 1;
 273   firstchar = (fs->min_byte1 << 8) + fs->min_char_or_byte2;
 274   lastchar = (fs->max_byte1 << 8) + fs->max_char_or_byte2;
 275   rows = fs->max_byte1 - fs->min_byte1 + 1;
 276   unsigned int first_char, last_char, pages, rows;
 277 #endif
 278
 279   /* Save the current packing mode for bitmaps.  */
 280   glGetIntegerv (GL_UNPACK_SWAP_BYTES, &swapbytes);
 281   glGetIntegerv (GL_UNPACK_LSB_FIRST, &lsbfirst);
 282   glGetIntegerv (GL_UNPACK_ROW_LENGTH, &rowlength);
 283   glGetIntegerv (GL_UNPACK_SKIP_ROWS, &skiprows);
 284   glGetIntegerv (GL_UNPACK_SKIP_PIXELS, &skippixels);
 285   glGetIntegerv (GL_UNPACK_ALIGNMENT, &alignment);
 286
 287   /* Enforce a standard packing mode which is compatible with
 288      fill_bitmap() from above.  This is actually the default mode,
 289      except for the (non)alignment.  */
 290   glPixelStorei (GL_UNPACK_SWAP_BYTES, GL_FALSE);
 291   glPixelStorei (GL_UNPACK_LSB_FIRST, GL_FALSE);
 292   glPixelStorei (GL_UNPACK_ROW_LENGTH, 0);
 293   glPixelStorei (GL_UNPACK_SKIP_ROWS, 0);
 294   glPixelStorei (GL_UNPACK_SKIP_PIXELS, 0);
 295   glPixelStorei (GL_UNPACK_ALIGNMENT, 1);
 296
 297   pixmap = XCreatePixmap (dpy, win, 10, 10, 1);
 298   values.foreground = BlackPixel (dpy, DefaultScreen (dpy));
 299   values.background = WhitePixel (dpy, DefaultScreen (dpy));
 300   values.font = fs->fid;
 301   valuemask = GCForeground | GCBackground | GCFont;
 302   gc = XCreateGC (dpy, pixmap, valuemask, &values);
 303   XFreePixmap (dpy, pixmap);
 304
 305 #ifdef DEBUG
 306   if (debug_xfonts)
 307     dump_font_struct (fs);
 308 #endif
 309
 310   for (i = 0; i < count; i++)
 311     {
 312       unsigned int width, height, bm_width, bm_height;
 313       GLfloat x0, y0, dx, dy;
 314       XCharStruct *ch;
 315       int x, y;
 316       unsigned int c = first + i;
 317       int list = listbase + i;
 318       int valid;
 319
 320       /* check on index validity and get the bounds */
 321       ch = isvalid(fs, c);
 322       if (!ch) {
 323         ch = &fs->max_bounds;
 324         valid = 0;
 325       } else {
 326         valid = 1;
 327       }
 328
 329 #ifdef DEBUG
 330       if (debug_xfonts) {
 331           char s[7];
 332           sprintf (s, isprint (c) ? "%c> " : "\\%03o> ", c);
 333           dump_char_struct (ch, s);
 334       }
 335 #endif
 336
 337       /* glBitmap()' parameters:
 338          straight from the glXUseXFont(3) manpage.  */
 339       width = ch->rbearing - ch->lbearing;
 340       height = ch->ascent + ch->descent;
 341       x0 = - ch->lbearing;
 342       y0 = ch->descent - 0;  /* XXX used to subtract 1 here */
 343                              /* but that caused a conformace failure */
 344       dx = ch->width;
 345       dy = 0;
 346
 347       /* X11's starting point.  */
 348       x = - ch->lbearing;
 349       y = ch->ascent;
 350
 351       /* Round the width to a multiple of eight.  We will use this also
 352          for the pixmap for capturing the X11 font.  This is slightly
 353          inefficient, but it makes the OpenGL part real easy.  */
 354       bm_width = (width + 7) / 8;
 355       bm_height = height;
 356
 357       glNewList (list, GL_COMPILE);
 358         if (valid && (bm_width > 0) && (bm_height > 0)) {
 359
 360             MEMSET (bm, '\0', bm_width * bm_height);
 361             fill_bitmap (dpy, win, gc, bm_width, bm_height, x, y, c, bm);
 362
 363             glBitmap (width, height, x0, y0, dx, dy, bm);
 364 #ifdef DEBUG
 365             if (debug_xfonts) {
 366                 printf ("width/height = %u/%u\n", width, height);
 367                 printf ("bm_width/bm_height = %u/%u\n", bm_width,
 368 bm_height);
 369                 dump_bitmap (bm_width, bm_height, bm);
 370               }
 371 #endif
 372           } else {
 373             glBitmap (0, 0, 0.0, 0.0, dx, dy, NULL);
 374           }
 375       glEndList ();
 376     }
 377
 378   FREE(bm);
 379   XFreeFontInfo( NULL, fs, 0 );
 380   XFreeGC (dpy, gc);
 381
 382   /* Restore saved packing modes.  */
 383   glPixelStorei(GL_UNPACK_SWAP_BYTES, swapbytes);
 384   glPixelStorei(GL_UNPACK_LSB_FIRST, lsbfirst);
 385   glPixelStorei(GL_UNPACK_ROW_LENGTH, rowlength);
 386   glPixelStorei(GL_UNPACK_SKIP_ROWS, skiprows);
 387   glPixelStorei(GL_UNPACK_SKIP_PIXELS, skippixels);
 388   glPixelStorei(GL_UNPACK_ALIGNMENT, alignment);
 389 }
 390
 391
 392 extern void xmesa_xfonts_dummy( void );
 393 void xmesa_xfonts_dummy( void )
 394 {
 395    /* silence unused var warnings */
 396    (void) kernel8;
 397    (void) DitherValues;
 398    (void) HPCR_DRGB;
 399    (void) kernel1;
 400 }
 401
 402 /* The End. */