1
2 /*
3 * Mesa 3-D graphics library
4 *
5 * Copyright (C) 1999-2000 Brian Paul All Rights Reserved.
6 *
7 * Permission is hereby granted, free of charge, to any person obtaining a
8 * copy of this software and associated documentation files (the "Software"),
9 * to deal in the Software without restriction, including without limitation
10 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
11 * and/or sell copies of the Software, and to permit persons to whom the
12 * Software is furnished to do so, subject to the following conditions:
13 *
14 * The above copyright notice and this permission notice shall be included
15 * in all copies or substantial portions of the Software.
16 *
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
18 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
20 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
21 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
22 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
23 * OTHER DEALINGS IN THE SOFTWARE.
24 */
25
26
27 /* xfonts.c -- glXUseXFont() for Mesa written by
28 * Copyright (C) 1995 Thorsten.Ohl @ Physik.TH-Darmstadt.de
29 */
30
31 #include <stdio.h>
32 #include "glxheader.h"
33 #include "main/context.h"
34 #include "main/imports.h"
35 #include "xfonts.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
dump_char_struct(XCharStruct * ch,char * prefix)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
dump_font_struct(XFontStruct * font)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
dump_bitmap(unsigned int width,unsigned int height,GLubyte * bitmap)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
fill_bitmap(Display * dpy,Window win,GC gc,unsigned int width,unsigned int height,int x0,int y0,unsigned int c,GLubyte * bitmap)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 *
isvalid(XFontStruct * fs,unsigned int which)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 void
Fake_glXUseXFont(Font font,int first,int count,int listbase)211 Fake_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 win = RootWindow(dpy, DefaultScreen(dpy));
230
231 fs = XQueryFont(dpy, font);
232 if (!fs) {
233 _mesa_error(NULL, GL_INVALID_VALUE,
234 "Couldn't get font structure information");
235 return;
236 }
237
238 /* Allocate a bitmap that can fit all characters. */
239 max_width = fs->max_bounds.rbearing - fs->min_bounds.lbearing;
240 max_height = fs->max_bounds.ascent + fs->max_bounds.descent;
241 max_bm_width = (max_width + 7) / 8;
242 max_bm_height = max_height;
243
244 bm = malloc((max_bm_width * max_bm_height) * sizeof(GLubyte));
245 if (!bm) {
246 XFreeFontInfo(NULL, fs, 1);
247 _mesa_error(NULL, GL_OUT_OF_MEMORY,
248 "Couldn't allocate bitmap in glXUseXFont()");
249 return;
250 }
251
252 #if 0
253 /* get the page info */
254 pages = fs->max_char_or_byte2 - fs->min_char_or_byte2 + 1;
255 firstchar = (fs->min_byte1 << 8) + fs->min_char_or_byte2;
256 lastchar = (fs->max_byte1 << 8) + fs->max_char_or_byte2;
257 rows = fs->max_byte1 - fs->min_byte1 + 1;
258 unsigned int first_char, last_char, pages, rows;
259 #endif
260
261 /* Save the current packing mode for bitmaps. */
262 glGetIntegerv(GL_UNPACK_SWAP_BYTES, &swapbytes);
263 glGetIntegerv(GL_UNPACK_LSB_FIRST, &lsbfirst);
264 glGetIntegerv(GL_UNPACK_ROW_LENGTH, &rowlength);
265 glGetIntegerv(GL_UNPACK_SKIP_ROWS, &skiprows);
266 glGetIntegerv(GL_UNPACK_SKIP_PIXELS, &skippixels);
267 glGetIntegerv(GL_UNPACK_ALIGNMENT, &alignment);
268
269 /* Enforce a standard packing mode which is compatible with
270 fill_bitmap() from above. This is actually the default mode,
271 except for the (non)alignment. */
272 glPixelStorei(GL_UNPACK_SWAP_BYTES, GL_FALSE);
273 glPixelStorei(GL_UNPACK_LSB_FIRST, GL_FALSE);
274 glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
275 glPixelStorei(GL_UNPACK_SKIP_ROWS, 0);
276 glPixelStorei(GL_UNPACK_SKIP_PIXELS, 0);
277 glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
278
279 pixmap = XCreatePixmap(dpy, win, 10, 10, 1);
280 values.foreground = BlackPixel(dpy, DefaultScreen(dpy));
281 values.background = WhitePixel(dpy, DefaultScreen(dpy));
282 values.font = fs->fid;
283 valuemask = GCForeground | GCBackground | GCFont;
284 gc = XCreateGC(dpy, pixmap, valuemask, &values);
285 XFreePixmap(dpy, pixmap);
286
287 #ifdef DEBUG
288 if (debug_xfonts)
289 dump_font_struct(fs);
290 #endif
291
292 for (i = 0; i < count; i++) {
293 unsigned int width, height, bm_width, bm_height;
294 GLfloat x0, y0, dx, dy;
295 XCharStruct *ch;
296 int x, y;
297 unsigned int c = first + i;
298 int list = listbase + i;
299 int valid;
300
301 /* check on index validity and get the bounds */
302 ch = isvalid(fs, c);
303 if (!ch) {
304 ch = &fs->max_bounds;
305 valid = 0;
306 }
307 else {
308 valid = 1;
309 }
310
311 #ifdef DEBUG
312 if (debug_xfonts) {
313 char s[7];
314 sprintf(s, isprint(c) ? "%c> " : "\\%03o> ", c);
315 dump_char_struct(ch, s);
316 }
317 #endif
318
319 /* glBitmap()' parameters:
320 straight from the glXUseXFont(3) manpage. */
321 width = ch->rbearing - ch->lbearing;
322 height = ch->ascent + ch->descent;
323 x0 = -ch->lbearing;
324 y0 = ch->descent - 0; /* XXX used to subtract 1 here */
325 /* but that caused a conformace failure */
326 dx = ch->width;
327 dy = 0;
328
329 /* X11's starting point. */
330 x = -ch->lbearing;
331 y = ch->ascent;
332
333 /* Round the width to a multiple of eight. We will use this also
334 for the pixmap for capturing the X11 font. This is slightly
335 inefficient, but it makes the OpenGL part real easy. */
336 bm_width = (width + 7) / 8;
337 bm_height = height;
338
339 glNewList(list, GL_COMPILE);
340 if (valid && (bm_width > 0) && (bm_height > 0)) {
341
342 memset(bm, '\0', bm_width * bm_height);
343 fill_bitmap(dpy, win, gc, bm_width, bm_height, x, y, c, bm);
344
345 glBitmap(width, height, x0, y0, dx, dy, bm);
346 #ifdef DEBUG
347 if (debug_xfonts) {
348 printf("width/height = %u/%u\n", width, height);
349 printf("bm_width/bm_height = %u/%u\n", bm_width, bm_height);
350 dump_bitmap(bm_width, bm_height, bm);
351 }
352 #endif
353 }
354 else {
355 glBitmap(0, 0, 0.0, 0.0, dx, dy, NULL);
356 }
357 glEndList();
358 }
359
360 free(bm);
361 XFreeFontInfo(NULL, fs, 1);
362 XFreeGC(dpy, gc);
363
364 /* Restore saved packing modes. */
365 glPixelStorei(GL_UNPACK_SWAP_BYTES, swapbytes);
366 glPixelStorei(GL_UNPACK_LSB_FIRST, lsbfirst);
367 glPixelStorei(GL_UNPACK_ROW_LENGTH, rowlength);
368 glPixelStorei(GL_UNPACK_SKIP_ROWS, skiprows);
369 glPixelStorei(GL_UNPACK_SKIP_PIXELS, skippixels);
370 glPixelStorei(GL_UNPACK_ALIGNMENT, alignment);
371 }
372