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