1 /* 2 * Mesa 3-D graphics library 3 * 4 * Copyright (C) 1995 Thorsten.Ohl @ Physik.TH-Darmstadt.de 5 * Copyright (C) 1999-2008 Brian Paul All Rights Reserved. 6 * Copyright (C) 2009 VMware, Inc. All Rights Reserved. 7 * 8 * Permission is hereby granted, free of charge, to any person obtaining a 9 * copy of this software and associated documentation files (the "Software"), 10 * to deal in the Software without restriction, including without limitation 11 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 12 * and/or sell copies of the Software, and to permit persons to whom the 13 * Software is furnished to do so, subject to the following conditions: 14 * 15 * The above copyright notice and this permission notice shall be included 16 * in all copies or substantial portions of the Software. 17 * 18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS 19 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 20 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 21 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR 22 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, 23 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR 24 * OTHER DEALINGS IN THE SOFTWARE. 25 */ 26 27 28 /** 29 * Fake implementation of glXUseXFont(). 30 */ 31 32 33 #include <stdio.h> 34 #include "main/core.h" 35 #include <GL/glx.h> 36 37 38 /* Some debugging info. */ 39 40 #ifdef DEBUG 41 #include <ctype.h> 42 43 int debug_xfonts = 0; 44 45 static void 46 dump_char_struct(XCharStruct * ch, char *prefix) 47 { 48 printf("%slbearing = %d, rbearing = %d, width = %d\n", 49 prefix, ch->lbearing, ch->rbearing, ch->width); 50 printf("%sascent = %d, descent = %d, attributes = %u\n", 51 prefix, ch->ascent, ch->descent, (unsigned int) ch->attributes); 52 } 53 54 static void 55 dump_font_struct(XFontStruct * font) 56 { 57 printf("ascent = %d, descent = %d\n", font->ascent, font->descent); 58 printf("char_or_byte2 = (%u,%u)\n", 59 font->min_char_or_byte2, font->max_char_or_byte2); 60 printf("byte1 = (%u,%u)\n", font->min_byte1, font->max_byte1); 61 printf("all_chars_exist = %s\n", font->all_chars_exist ? "True" : "False"); 62 printf("default_char = %c (\\%03o)\n", 63 (char) (isprint(font->default_char) ? font->default_char : ' '), 64 font->default_char); 65 dump_char_struct(&font->min_bounds, "min> "); 66 dump_char_struct(&font->max_bounds, "max> "); 67 #if 0 68 for (c = font->min_char_or_byte2; c <= font->max_char_or_byte2; c++) { 69 char prefix[8]; 70 sprintf(prefix, "%d> ", c); 71 dump_char_struct(&font->per_char[c], prefix); 72 } 73 #endif 74 } 75 76 static void 77 dump_bitmap(unsigned int width, unsigned int height, GLubyte * bitmap) 78 { 79 unsigned int x, y; 80 81 printf(" "); 82 for (x = 0; x < 8 * width; x++) 83 printf("%o", 7 - (x % 8)); 84 putchar('\n'); 85 for (y = 0; y < height; y++) { 86 printf("%3o:", y); 87 for (x = 0; x < 8 * width; x++) 88 putchar((bitmap[width * (height - y - 1) + x / 8] & (1 << (7 - (x % 89 8)))) 90 ? '*' : '.'); 91 printf(" "); 92 for (x = 0; x < width; x++) 93 printf("0x%02x, ", bitmap[width * (height - y - 1) + x]); 94 putchar('\n'); 95 } 96 } 97 #endif /* DEBUG */ 98 99 100 /* Implementation. */ 101 102 /* Fill a BITMAP with a character C from thew current font 103 in the graphics context GC. WIDTH is the width in bytes 104 and HEIGHT is the height in bits. 105 106 Note that the generated bitmaps must be used with 107 108 glPixelStorei (GL_UNPACK_SWAP_BYTES, GL_FALSE); 109 glPixelStorei (GL_UNPACK_LSB_FIRST, GL_FALSE); 110 glPixelStorei (GL_UNPACK_ROW_LENGTH, 0); 111 glPixelStorei (GL_UNPACK_SKIP_ROWS, 0); 112 glPixelStorei (GL_UNPACK_SKIP_PIXELS, 0); 113 glPixelStorei (GL_UNPACK_ALIGNMENT, 1); 114 115 Possible optimizations: 116 117 * use only one reusable pixmap with the maximum dimensions. 118 * draw the entire font into a single pixmap (careful with 119 proportional fonts!). 120 */ 121 122 123 /* 124 * Generate OpenGL-compatible bitmap. 125 */ 126 static void 127 fill_bitmap(Display * dpy, Window win, GC gc, 128 unsigned int width, unsigned int height, 129 int x0, int y0, unsigned int c, GLubyte * bitmap) 130 { 131 XImage *image; 132 unsigned int x, y; 133 Pixmap pixmap; 134 XChar2b char2b; 135 136 pixmap = XCreatePixmap(dpy, win, 8 * width, height, 1); 137 XSetForeground(dpy, gc, 0); 138 XFillRectangle(dpy, pixmap, gc, 0, 0, 8 * width, height); 139 XSetForeground(dpy, gc, 1); 140 141 char2b.byte1 = (c >> 8) & 0xff; 142 char2b.byte2 = (c & 0xff); 143 144 XDrawString16(dpy, pixmap, gc, x0, y0, &char2b, 1); 145 146 image = XGetImage(dpy, pixmap, 0, 0, 8 * width, height, 1, XYPixmap); 147 if (image) { 148 /* Fill the bitmap (X11 and OpenGL are upside down wrt each other). */ 149 for (y = 0; y < height; y++) 150 for (x = 0; x < 8 * width; x++) 151 if (XGetPixel(image, x, y)) 152 bitmap[width * (height - y - 1) + x / 8] |= 153 (1 << (7 - (x % 8))); 154 XDestroyImage(image); 155 } 156 157 XFreePixmap(dpy, pixmap); 158 } 159 160 /* 161 * determine if a given glyph is valid and return the 162 * corresponding XCharStruct. 163 */ 164 static XCharStruct * 165 isvalid(XFontStruct * fs, unsigned int which) 166 { 167 unsigned int rows, pages; 168 unsigned int byte1 = 0, byte2 = 0; 169 int i, valid = 1; 170 171 rows = fs->max_byte1 - fs->min_byte1 + 1; 172 pages = fs->max_char_or_byte2 - fs->min_char_or_byte2 + 1; 173 174 if (rows == 1) { 175 /* "linear" fonts */ 176 if ((fs->min_char_or_byte2 > which) || (fs->max_char_or_byte2 < which)) 177 valid = 0; 178 } 179 else { 180 /* "matrix" fonts */ 181 byte2 = which & 0xff; 182 byte1 = which >> 8; 183 if ((fs->min_char_or_byte2 > byte2) || 184 (fs->max_char_or_byte2 < byte2) || 185 (fs->min_byte1 > byte1) || (fs->max_byte1 < byte1)) 186 valid = 0; 187 } 188 189 if (valid) { 190 if (fs->per_char) { 191 if (rows == 1) { 192 /* "linear" fonts */ 193 return (fs->per_char + (which - fs->min_char_or_byte2)); 194 } 195 else { 196 /* "matrix" fonts */ 197 i = ((byte1 - fs->min_byte1) * pages) + 198 (byte2 - fs->min_char_or_byte2); 199 return (fs->per_char + i); 200 } 201 } 202 else { 203 return (&fs->min_bounds); 204 } 205 } 206 return (NULL); 207 } 208 209 210 PUBLIC void 211 glXUseXFont(Font font, int first, int count, int listbase) 212 { 213 Display *dpy; 214 Window win; 215 Pixmap pixmap; 216 GC gc; 217 XGCValues values; 218 unsigned long valuemask; 219 XFontStruct *fs; 220 GLint swapbytes, lsbfirst, rowlength; 221 GLint skiprows, skippixels, alignment; 222 unsigned int max_width, max_height, max_bm_width, max_bm_height; 223 GLubyte *bm; 224 int i; 225 226 dpy = glXGetCurrentDisplay(); 227 if (!dpy) 228 return; /* I guess glXMakeCurrent wasn't called */ 229 i = DefaultScreen(dpy); 230 win = RootWindow(dpy, i); 231 232 fs = XQueryFont(dpy, font); 233 if (!fs) { 234 _mesa_error(NULL, GL_INVALID_VALUE, 235 "Couldn't get font structure information"); 236 return; 237 } 238 239 /* Allocate a bitmap that can fit all characters. */ 240 max_width = fs->max_bounds.rbearing - fs->min_bounds.lbearing; 241 max_height = fs->max_bounds.ascent + fs->max_bounds.descent; 242 max_bm_width = (max_width + 7) / 8; 243 max_bm_height = max_height; 244 245 bm = malloc((max_bm_width * max_bm_height) * sizeof(GLubyte)); 246 if (!bm) { 247 XFreeFontInfo(NULL, fs, 1); 248 _mesa_error(NULL, GL_OUT_OF_MEMORY, 249 "Couldn't allocate bitmap in glXUseXFont()"); 250 return; 251 } 252 253 #if 0 254 /* get the page info */ 255 pages = fs->max_char_or_byte2 - fs->min_char_or_byte2 + 1; 256 firstchar = (fs->min_byte1 << 8) + fs->min_char_or_byte2; 257 lastchar = (fs->max_byte1 << 8) + fs->max_char_or_byte2; 258 rows = fs->max_byte1 - fs->min_byte1 + 1; 259 unsigned int first_char, last_char, pages, rows; 260 #endif 261 262 /* Save the current packing mode for bitmaps. */ 263 glGetIntegerv(GL_UNPACK_SWAP_BYTES, &swapbytes); 264 glGetIntegerv(GL_UNPACK_LSB_FIRST, &lsbfirst); 265 glGetIntegerv(GL_UNPACK_ROW_LENGTH, &rowlength); 266 glGetIntegerv(GL_UNPACK_SKIP_ROWS, &skiprows); 267 glGetIntegerv(GL_UNPACK_SKIP_PIXELS, &skippixels); 268 glGetIntegerv(GL_UNPACK_ALIGNMENT, &alignment); 269 270 /* Enforce a standard packing mode which is compatible with 271 fill_bitmap() from above. This is actually the default mode, 272 except for the (non)alignment. */ 273 glPixelStorei(GL_UNPACK_SWAP_BYTES, GL_FALSE); 274 glPixelStorei(GL_UNPACK_LSB_FIRST, GL_FALSE); 275 glPixelStorei(GL_UNPACK_ROW_LENGTH, 0); 276 glPixelStorei(GL_UNPACK_SKIP_ROWS, 0); 277 glPixelStorei(GL_UNPACK_SKIP_PIXELS, 0); 278 glPixelStorei(GL_UNPACK_ALIGNMENT, 1); 279 280 pixmap = XCreatePixmap(dpy, win, 10, 10, 1); 281 values.foreground = BlackPixel(dpy, DefaultScreen(dpy)); 282 values.background = WhitePixel(dpy, DefaultScreen(dpy)); 283 values.font = fs->fid; 284 valuemask = GCForeground | GCBackground | GCFont; 285 gc = XCreateGC(dpy, pixmap, valuemask, &values); 286 XFreePixmap(dpy, pixmap); 287 288 #ifdef DEBUG 289 if (debug_xfonts) 290 dump_font_struct(fs); 291 #endif 292 293 for (i = 0; i < count; i++) { 294 unsigned int width, height, bm_width, bm_height; 295 GLfloat x0, y0, dx, dy; 296 XCharStruct *ch; 297 int x, y; 298 unsigned int c = first + i; 299 int list = listbase + i; 300 int valid; 301 302 /* check on index validity and get the bounds */ 303 ch = isvalid(fs, c); 304 if (!ch) { 305 ch = &fs->max_bounds; 306 valid = 0; 307 } 308 else { 309 valid = 1; 310 } 311 312 #ifdef DEBUG 313 if (debug_xfonts) { 314 char s[7]; 315 sprintf(s, isprint(c) ? "%c> " : "\\%03o> ", c); 316 dump_char_struct(ch, s); 317 } 318 #endif 319 320 /* glBitmap()' parameters: 321 straight from the glXUseXFont(3) manpage. */ 322 width = ch->rbearing - ch->lbearing; 323 height = ch->ascent + ch->descent; 324 x0 = -ch->lbearing; 325 y0 = ch->descent - 0; /* XXX used to subtract 1 here */ 326 /* but that caused a conformace failure */ 327 dx = ch->width; 328 dy = 0; 329 330 /* X11's starting point. */ 331 x = -ch->lbearing; 332 y = ch->ascent; 333 334 /* Round the width to a multiple of eight. We will use this also 335 for the pixmap for capturing the X11 font. This is slightly 336 inefficient, but it makes the OpenGL part real easy. */ 337 bm_width = (width + 7) / 8; 338 bm_height = height; 339 340 glNewList(list, GL_COMPILE); 341 if (valid && (bm_width > 0) && (bm_height > 0)) { 342 343 memset(bm, '\0', bm_width * bm_height); 344 fill_bitmap(dpy, win, gc, bm_width, bm_height, x, y, c, bm); 345 346 glBitmap(width, height, x0, y0, dx, dy, bm); 347 #ifdef DEBUG 348 if (debug_xfonts) { 349 printf("width/height = %u/%u\n", width, height); 350 printf("bm_width/bm_height = %u/%u\n", bm_width, bm_height); 351 dump_bitmap(bm_width, bm_height, bm); 352 } 353 #endif 354 } 355 else { 356 glBitmap(0, 0, 0.0, 0.0, dx, dy, NULL); 357 } 358 glEndList(); 359 } 360 361 free(bm); 362 XFreeFontInfo(NULL, fs, 1); 363 XFreeGC(dpy, gc); 364 365 /* Restore saved packing modes. */ 366 glPixelStorei(GL_UNPACK_SWAP_BYTES, swapbytes); 367 glPixelStorei(GL_UNPACK_LSB_FIRST, lsbfirst); 368 glPixelStorei(GL_UNPACK_ROW_LENGTH, rowlength); 369 glPixelStorei(GL_UNPACK_SKIP_ROWS, skiprows); 370 glPixelStorei(GL_UNPACK_SKIP_PIXELS, skippixels); 371 glPixelStorei(GL_UNPACK_ALIGNMENT, alignment); 372 } 373
