xm_api.c revision 0983163fde91f1026146903155fd414725a79879
1/*
2 * Mesa 3-D graphics library
3 * Version:  5.1
4 *
5 * Copyright (C) 1999-2003  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 * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
21 * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
22 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
23 */
24/* $XFree86: xc/extras/Mesa/src/X/xm_api.c,v 1.2 2002/02/26 23:37:31 tsi Exp $ */
25
26/*
27 * This file contains the implementations of all the XMesa* functions.
28 *
29 *
30 * NOTES:
31 *
32 * The window coordinate system origin (0,0) is in the lower-left corner
33 * of the window.  X11's window coordinate origin is in the upper-left
34 * corner of the window.  Therefore, most drawing functions in this
35 * file have to flip Y coordinates.
36 *
37 * Define USE_XSHM in the Makefile with -DUSE_XSHM if you want to compile
38 * in support for the MIT Shared Memory extension.  If enabled, when you
39 * use an Ximage for the back buffer in double buffered mode, the "swap"
40 * operation will be faster.  You must also link with -lXext.
41 *
42 * Byte swapping:  If the Mesa host and the X display use a different
43 * byte order then there's some trickiness to be aware of when using
44 * XImages.  The byte ordering used for the XImage is that of the X
45 * display, not the Mesa host.
46 * The color-to-pixel encoding for True/DirectColor must be done
47 * according to the display's visual red_mask, green_mask, and blue_mask.
48 * If XPutPixel is used to put a pixel into an XImage then XPutPixel will
49 * do byte swapping if needed.  If one wants to directly "poke" the pixel
50 * into the XImage's buffer then the pixel must be byte swapped first.  In
51 * Mesa, when byte swapping is needed we use the PF_TRUECOLOR pixel format
52 * and use XPutPixel everywhere except in the implementation of
53 * glClear(GL_COLOR_BUFFER_BIT).  We want this function to be fast so
54 * instead of using XPutPixel we "poke" our values after byte-swapping
55 * the clear pixel value if needed.
56 *
57 */
58
59#ifdef __CYGWIN__
60#undef WIN32
61#undef __WIN32__
62#endif
63
64#include "glxheader.h"
65#include "GL/xmesa.h"
66#include "xmesaP.h"
67#include "context.h"
68#include "extensions.h"
69#include "glthread.h"
70#include "imports.h"
71#include "matrix.h"
72#include "mtypes.h"
73#include "macros.h"
74#include "texformat.h"
75#include "texobj.h"
76#include "texstore.h"
77#include "swrast/swrast.h"
78#include "swrast_setup/swrast_setup.h"
79#include "array_cache/acache.h"
80#include "tnl/tnl.h"
81
82#ifndef GLX_NONE_EXT
83#define GLX_NONE_EXT 0x8000
84#endif
85
86
87/*
88 * Global X driver lock
89 */
90_glthread_Mutex _xmesa_lock;
91
92
93
94/*
95 * Lookup tables for HPCR pixel format:
96 */
97static short hpcr_rgbTbl[3][256] = {
98{
99 16,  16,  17,  17,  18,  18,  19,  19,  20,  20,  21,  21,  22,  22,  23,  23,
100 24,  24,  25,  25,  26,  26,  27,  27,  28,  28,  29,  29,  30,  30,  31,  31,
101 32,  32,  33,  33,  34,  34,  35,  35,  36,  36,  37,  37,  38,  38,  39,  39,
102 32,  33,  34,  35,  36,  37,  38,  39,  40,  41,  42,  43,  44,  45,  46,  47,
103 48,  49,  50,  51,  52,  53,  54,  55,  56,  57,  58,  59,  60,  61,  62,  63,
104 64,  65,  66,  67,  68,  69,  70,  71,  72,  73,  74,  75,  76,  77,  78,  79,
105 80,  81,  82,  83,  84,  85,  86,  87,  88,  89,  90,  91,  92,  93,  94,  95,
106 96,  97,  98,  99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111,
107112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127,
108128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143,
109144, 145, 146, 147, 148, 149, 150, 151, 152, 153, 154, 155, 156, 157, 158, 159,
110160, 161, 162, 163, 164, 165, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175,
111176, 177, 178, 179, 180, 181, 182, 183, 184, 185, 186, 187, 188, 189, 190, 191,
112192, 193, 194, 195, 196, 197, 198, 199, 200, 201, 202, 203, 204, 205, 206, 207,
113208, 209, 210, 211, 212, 213, 214, 215, 216, 217, 218, 219, 220, 221, 222, 223,
114224, 225, 226, 227, 228, 229, 230, 231, 232, 233, 234, 235, 236, 237, 238, 239
115},
116{
117 16,  16,  17,  17,  18,  18,  19,  19,  20,  20,  21,  21,  22,  22,  23,  23,
118 24,  24,  25,  25,  26,  26,  27,  27,  28,  28,  29,  29,  30,  30,  31,  31,
119 32,  32,  33,  33,  34,  34,  35,  35,  36,  36,  37,  37,  38,  38,  39,  39,
120 32,  33,  34,  35,  36,  37,  38,  39,  40,  41,  42,  43,  44,  45,  46,  47,
121 48,  49,  50,  51,  52,  53,  54,  55,  56,  57,  58,  59,  60,  61,  62,  63,
122 64,  65,  66,  67,  68,  69,  70,  71,  72,  73,  74,  75,  76,  77,  78,  79,
123 80,  81,  82,  83,  84,  85,  86,  87,  88,  89,  90,  91,  92,  93,  94,  95,
124 96,  97,  98,  99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111,
125112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127,
126128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143,
127144, 145, 146, 147, 148, 149, 150, 151, 152, 153, 154, 155, 156, 157, 158, 159,
128160, 161, 162, 163, 164, 165, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175,
129176, 177, 178, 179, 180, 181, 182, 183, 184, 185, 186, 187, 188, 189, 190, 191,
130192, 193, 194, 195, 196, 197, 198, 199, 200, 201, 202, 203, 204, 205, 206, 207,
131208, 209, 210, 211, 212, 213, 214, 215, 216, 217, 218, 219, 220, 221, 222, 223,
132224, 225, 226, 227, 228, 229, 230, 231, 232, 233, 234, 235, 236, 237, 238, 239
133},
134{
135 32,  32,  33,  33,  34,  34,  35,  35,  36,  36,  37,  37,  38,  38,  39,  39,
136 40,  40,  41,  41,  42,  42,  43,  43,  44,  44,  45,  45,  46,  46,  47,  47,
137 48,  48,  49,  49,  50,  50,  51,  51,  52,  52,  53,  53,  54,  54,  55,  55,
138 56,  56,  57,  57,  58,  58,  59,  59,  60,  60,  61,  61,  62,  62,  63,  63,
139 64,  64,  65,  65,  66,  66,  67,  67,  68,  68,  69,  69,  70,  70,  71,  71,
140 72,  72,  73,  73,  74,  74,  75,  75,  76,  76,  77,  77,  78,  78,  79,  79,
141 80,  80,  81,  81,  82,  82,  83,  83,  84,  84,  85,  85,  86,  86,  87,  87,
142 80,  81,  82,  83,  84,  85,  86,  87,  88,  89,  90,  91,  92,  93,  94,  95,
143 96,  97,  98,  99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111,
144112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127,
145128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143,
146144, 145, 146, 147, 148, 149, 150, 151, 152, 153, 154, 155, 156, 157, 158, 159,
147160, 161, 162, 163, 164, 165, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175,
148176, 177, 178, 179, 180, 181, 182, 183, 184, 185, 186, 187, 188, 189, 190, 191,
149192, 193, 194, 195, 196, 197, 198, 199, 200, 201, 202, 203, 204, 205, 206, 207,
150208, 209, 210, 211, 212, 213, 214, 215, 216, 217, 218, 219, 220, 221, 222, 223
151}
152};
153
154
155
156/**********************************************************************/
157/*****                     X Utility Functions                    *****/
158/**********************************************************************/
159
160
161/*
162 * Return the host's byte order as LSBFirst or MSBFirst ala X.
163 */
164#ifndef XFree86Server
165static int host_byte_order( void )
166{
167   int i = 1;
168   char *cptr = (char *) &i;
169   return (*cptr==1) ? LSBFirst : MSBFirst;
170}
171#endif
172
173
174/*
175 * Error handling.
176 */
177#ifndef XFree86Server
178static int mesaXErrorFlag = 0;
179
180static int mesaHandleXError( XMesaDisplay *dpy, XErrorEvent *event )
181{
182   (void) dpy;
183   (void) event;
184   mesaXErrorFlag = 1;
185   return 0;
186}
187#endif
188
189
190/*
191 * Check if the X Shared Memory extension is available.
192 * Return:  0 = not available
193 *          1 = shared XImage support available
194 *          2 = shared Pixmap support available also
195 */
196#ifndef XFree86Server
197static int check_for_xshm( XMesaDisplay *display )
198{
199#ifdef USE_XSHM
200   int major, minor, ignore;
201   Bool pixmaps;
202
203   if (XQueryExtension( display, "MIT-SHM", &ignore, &ignore, &ignore )) {
204      if (XShmQueryVersion( display, &major, &minor, &pixmaps )==True) {
205	 return (pixmaps==True) ? 2 : 1;
206      }
207      else {
208	 return 0;
209      }
210   }
211   else {
212      return 0;
213   }
214#else
215   /* Can't compile XSHM support */
216   return 0;
217#endif
218}
219#endif
220
221
222/*
223 * Return the width and height of the given drawable.
224 */
225static void get_drawable_size( XMesaDisplay *dpy, XMesaDrawable d,
226                               unsigned int *width, unsigned int *height)
227{
228#ifdef XFree86Server
229    (void) dpy;
230    *width = d->width;
231    *height = d->height;
232#else
233   Window root;
234   int x, y;
235   unsigned int bw, depth;
236
237   _glthread_LOCK_MUTEX(_xmesa_lock);
238   XGetGeometry( dpy, d, &root, &x, &y, width, height, &bw, &depth );
239   _glthread_UNLOCK_MUTEX(_xmesa_lock);
240#endif
241}
242
243
244/*
245 * Apply gamma correction to an intensity value in [0..max].  Return the
246 * new intensity value.
247 */
248static GLint gamma_adjust( GLfloat gamma, GLint value, GLint max )
249{
250   if (gamma == 1.0) {
251      return value;
252   }
253   else {
254      double x = (double) value / (double) max;
255      return IROUND_POS((GLfloat) max * _mesa_pow(x, 1.0F/gamma));
256   }
257}
258
259
260
261/*
262 * Return the true number of bits per pixel for XImages.
263 * For example, if we request a 24-bit deep visual we may actually need/get
264 * 32bpp XImages.  This function returns the appropriate bpp.
265 * Input:  dpy - the X display
266 *         visinfo - desribes the visual to be used for XImages
267 * Return:  true number of bits per pixel for XImages
268 */
269#ifdef XFree86Server
270
271static int bits_per_pixel( XMesaVisual xmv )
272{
273   XMesaVisualInfo visinfo = xmv->visinfo;
274   const int depth = visinfo->nplanes;
275   int i;
276   for (i = 0; i < screenInfo.numPixmapFormats; i++) {
277      if (screenInfo.formats[i].depth == depth)
278         return screenInfo.formats[i].bitsPerPixel;
279   }
280   return depth;  /* should never get here, but this should be safe */
281}
282
283#else
284
285static int bits_per_pixel( XMesaVisual xmv )
286{
287   XMesaDisplay *dpy = xmv->display;
288   XMesaVisualInfo visinfo = xmv->visinfo;
289   XMesaImage *img;
290   int bitsPerPixel;
291   /* Create a temporary XImage */
292   img = XCreateImage( dpy, visinfo->visual, visinfo->depth,
293		       ZPixmap, 0,           /*format, offset*/
294		       (char*) MALLOC(8),    /*data*/
295		       1, 1,                 /*width, height*/
296		       32,                   /*bitmap_pad*/
297		       0                     /*bytes_per_line*/
298                     );
299   assert(img);
300   /* grab the bits/pixel value */
301   bitsPerPixel = img->bits_per_pixel;
302   /* free the XImage */
303   FREE( img->data );
304   img->data = NULL;
305   XMesaDestroyImage( img );
306   return bitsPerPixel;
307}
308#endif
309
310
311
312/*
313 * Determine if a given X window ID is valid (window exists).
314 * Do this by calling XGetWindowAttributes() for the window and
315 * checking if we catch an X error.
316 * Input:  dpy - the display
317 *         win - the window to check for existance
318 * Return:  GL_TRUE - window exists
319 *          GL_FALSE - window doesn't exist
320 */
321#ifndef XFree86Server
322static GLboolean WindowExistsFlag;
323
324static int window_exists_err_handler( XMesaDisplay* dpy, XErrorEvent* xerr )
325{
326   (void) dpy;
327   if (xerr->error_code == BadWindow) {
328      WindowExistsFlag = GL_FALSE;
329   }
330   return 0;
331}
332
333static GLboolean window_exists( XMesaDisplay *dpy, Window win )
334{
335   XWindowAttributes wa;
336   int (*old_handler)( XMesaDisplay*, XErrorEvent* );
337   WindowExistsFlag = GL_TRUE;
338   old_handler = XSetErrorHandler(window_exists_err_handler);
339   XGetWindowAttributes( dpy, win, &wa ); /* dummy request */
340   XSetErrorHandler(old_handler);
341   return WindowExistsFlag;
342}
343#endif
344
345
346
347/**********************************************************************/
348/*****                Linked list of XMesaBuffers                 *****/
349/**********************************************************************/
350
351static XMesaBuffer XMesaBufferList = NULL;
352
353
354/* Allocate a new XMesaBuffer, add to linked list */
355static XMesaBuffer alloc_xmesa_buffer(void)
356{
357   XMesaBuffer b = (XMesaBuffer) CALLOC_STRUCT(xmesa_buffer);
358   if (b) {
359      b->Next = XMesaBufferList;
360      XMesaBufferList = b;
361   }
362   return b;
363}
364
365
366/*
367 * Find an XMesaBuffer by matching X display and colormap but NOT matching
368 * the notThis buffer.
369 */
370static XMesaBuffer find_xmesa_buffer(XMesaDisplay *dpy,
371                                     XMesaColormap cmap,
372                                     XMesaBuffer notThis)
373{
374   XMesaBuffer b;
375   for (b=XMesaBufferList; b; b=b->Next) {
376      if (b->display==dpy && b->cmap==cmap && b!=notThis) {
377         return b;
378      }
379   }
380   return NULL;
381}
382
383
384/*
385 * Free an XMesaBuffer, remove from linked list, perhaps free X colormap
386 * entries.
387 */
388static void free_xmesa_buffer(int client, XMesaBuffer buffer)
389{
390   XMesaBuffer prev = NULL, b;
391   (void) client;
392   for (b=XMesaBufferList; b; b=b->Next) {
393      if (b==buffer) {
394         /* unlink bufer from list */
395         if (prev)
396            prev->Next = buffer->Next;
397         else
398            XMesaBufferList = buffer->Next;
399         /* Check to free X colors */
400         if (buffer->num_alloced>0) {
401            /* If no other buffer uses this X colormap then free the colors. */
402            if (!find_xmesa_buffer(buffer->display, buffer->cmap, buffer)) {
403#ifdef XFree86Server
404               (void)FreeColors(buffer->cmap, client,
405				buffer->num_alloced, buffer->alloced_colors,
406				0);
407#else
408               XFreeColors(buffer->display, buffer->cmap,
409                           buffer->alloced_colors, buffer->num_alloced, 0);
410#endif
411            }
412         }
413
414         _mesa_free_framebuffer_data(&buffer->mesa_buffer);
415         FREE(buffer);
416
417         return;
418      }
419      /* continue search */
420      prev = b;
421   }
422   /* buffer not found in XMesaBufferList */
423   _mesa_problem(NULL,"free_xmesa_buffer() - buffer not found\n");
424}
425
426
427/* Copy X color table stuff from one XMesaBuffer to another. */
428static void copy_colortable_info(XMesaBuffer dst, const XMesaBuffer src)
429{
430   MEMCPY(dst->color_table, src->color_table, sizeof(src->color_table));
431   MEMCPY(dst->pixel_to_r, src->pixel_to_r, sizeof(src->pixel_to_r));
432   MEMCPY(dst->pixel_to_g, src->pixel_to_g, sizeof(src->pixel_to_g));
433   MEMCPY(dst->pixel_to_b, src->pixel_to_b, sizeof(src->pixel_to_b));
434   dst->num_alloced = src->num_alloced;
435   MEMCPY(dst->alloced_colors, src->alloced_colors,
436          sizeof(src->alloced_colors));
437}
438
439
440
441/**********************************************************************/
442/*****                   Misc Private Functions                   *****/
443/**********************************************************************/
444
445
446/*
447 * Return number of bits set in n.
448 */
449static int bitcount( unsigned long n )
450{
451   int bits;
452   for (bits=0; n>0; n=n>>1) {
453      if (n&1) {
454         bits++;
455      }
456   }
457   return bits;
458}
459
460
461
462/*
463 * Allocate a shared memory XImage back buffer for the given XMesaBuffer.
464 * Return:  GL_TRUE if success, GL_FALSE if error
465 */
466#ifndef XFree86Server
467static GLboolean alloc_shm_back_buffer( XMesaBuffer b )
468{
469#ifdef USE_XSHM
470   /*
471    * We have to do a _lot_ of error checking here to be sure we can
472    * really use the XSHM extension.  It seems different servers trigger
473    * errors at different points if the extension won't work.  Therefore
474    * we have to be very careful...
475    */
476   GC gc;
477   int (*old_handler)( XMesaDisplay *, XErrorEvent * );
478
479   b->backimage = XShmCreateImage( b->xm_visual->display,
480                                   b->xm_visual->visinfo->visual,
481                                   b->xm_visual->visinfo->depth,
482				   ZPixmap, NULL, &b->shminfo,
483				   b->width, b->height );
484   if (b->backimage == NULL) {
485      _mesa_warning(NULL, "alloc_back_buffer: Shared memory error (XShmCreateImage), disabling.");
486      b->shm = 0;
487      return GL_FALSE;
488   }
489
490   b->shminfo.shmid = shmget( IPC_PRIVATE, b->backimage->bytes_per_line
491			     * b->backimage->height, IPC_CREAT|0777 );
492   if (b->shminfo.shmid < 0) {
493      _mesa_warning(NULL, "shmget failed while allocating back buffer");
494      XDestroyImage( b->backimage );
495      b->backimage = NULL;
496      _mesa_warning(NULL, "alloc_back_buffer: Shared memory error (shmget), disabling.");
497      b->shm = 0;
498      return GL_FALSE;
499   }
500
501   b->shminfo.shmaddr = b->backimage->data
502                      = (char*)shmat( b->shminfo.shmid, 0, 0 );
503   if (b->shminfo.shmaddr == (char *) -1) {
504      _mesa_warning(NULL, "shmat() failed while allocating back buffer");
505      XDestroyImage( b->backimage );
506      shmctl( b->shminfo.shmid, IPC_RMID, 0 );
507      b->backimage = NULL;
508      _mesa_warning(NULL, "alloc_back_buffer: Shared memory error (shmat), disabling.");
509      b->shm = 0;
510      return GL_FALSE;
511   }
512
513   b->shminfo.readOnly = False;
514   mesaXErrorFlag = 0;
515   old_handler = XSetErrorHandler( mesaHandleXError );
516   /* This may trigger the X protocol error we're ready to catch: */
517   XShmAttach( b->xm_visual->display, &b->shminfo );
518   XSync( b->xm_visual->display, False );
519
520   if (mesaXErrorFlag) {
521      /* we are on a remote display, this error is normal, don't print it */
522      XFlush( b->xm_visual->display );
523      mesaXErrorFlag = 0;
524      XDestroyImage( b->backimage );
525      shmdt( b->shminfo.shmaddr );
526      shmctl( b->shminfo.shmid, IPC_RMID, 0 );
527      b->backimage = NULL;
528      b->shm = 0;
529      (void) XSetErrorHandler( old_handler );
530      return GL_FALSE;
531   }
532
533   shmctl( b->shminfo.shmid, IPC_RMID, 0 ); /* nobody else needs it */
534
535   /* Finally, try an XShmPutImage to be really sure the extension works */
536   gc = XCreateGC( b->xm_visual->display, b->frontbuffer, 0, NULL );
537   XShmPutImage( b->xm_visual->display, b->frontbuffer, gc,
538		 b->backimage, 0, 0, 0, 0, 1, 1 /*one pixel*/, False );
539   XSync( b->xm_visual->display, False );
540   XFreeGC( b->xm_visual->display, gc );
541   (void) XSetErrorHandler( old_handler );
542   if (mesaXErrorFlag) {
543      XFlush( b->xm_visual->display );
544      mesaXErrorFlag = 0;
545      XDestroyImage( b->backimage );
546      shmdt( b->shminfo.shmaddr );
547      shmctl( b->shminfo.shmid, IPC_RMID, 0 );
548      b->backimage = NULL;
549      b->shm = 0;
550      return GL_FALSE;
551   }
552
553   if (b->backimage) {
554      int height = b->backimage->height;
555      /* Needed by PIXELADDR1 macro */
556      b->ximage_width1 = b->backimage->bytes_per_line;
557      b->ximage_origin1 = (GLubyte *) b->backimage->data
558                        + b->ximage_width1 * (height-1);
559      /* Needed by PIXELADDR2 macro */
560      b->ximage_width2 = b->backimage->bytes_per_line / 2;
561      b->ximage_origin2 = (GLushort *) b->backimage->data
562                        + b->ximage_width2 * (height-1);
563      /* Needed by PIXELADDR3 macro */
564      b->ximage_width3 = b->backimage->bytes_per_line;
565      b->ximage_origin3 = (GLubyte *) b->backimage->data
566                        + b->ximage_width3 * (height-1);
567      /* Needed by PIXELADDR4 macro */
568      b->ximage_width4 = b->backimage->width;
569      b->ximage_origin4 = (GLuint *) b->backimage->data
570                        + b->ximage_width4 * (height-1);
571   }
572
573   return GL_TRUE;
574#else
575   /* Can't compile XSHM support */
576   return GL_FALSE;
577#endif
578}
579#endif
580
581
582
583/*
584 * Setup an off-screen pixmap or Ximage to use as the back buffer.
585 * Input:  b - the X/Mesa buffer
586 */
587void xmesa_alloc_back_buffer( XMesaBuffer b )
588{
589   if (b->db_state==BACK_XIMAGE) {
590      /* Deallocate the old backimage, if any */
591      if (b->backimage) {
592#if defined(USE_XSHM) && !defined(XFree86Server)
593	 if (b->shm) {
594	    XShmDetach( b->xm_visual->display, &b->shminfo );
595	    XDestroyImage( b->backimage );
596	    shmdt( b->shminfo.shmaddr );
597	 }
598	 else
599#endif
600	   XMesaDestroyImage( b->backimage );
601	 b->backimage = NULL;
602      }
603
604      /* Allocate new back buffer */
605#ifdef XFree86Server
606      {
607	 /* Allocate a regular XImage for the back buffer. */
608	 b->backimage = XMesaCreateImage(b->xm_visual->BitsPerPixel,
609					 b->width, b->height, NULL);
610#else
611      if (b->shm==0 || alloc_shm_back_buffer(b)==GL_FALSE) {
612	 /* Allocate a regular XImage for the back buffer. */
613	 b->backimage = XCreateImage( b->xm_visual->display,
614                                      b->xm_visual->visinfo->visual,
615                                      GET_VISUAL_DEPTH(b->xm_visual),
616				      ZPixmap, 0,   /* format, offset */
617				      NULL, b->width, b->height,
618				      8, 0 );  /* pad, bytes_per_line */
619#endif
620	 if (!b->backimage) {
621	    _mesa_warning(NULL, "alloc_back_buffer: XCreateImage failed.");
622	 }
623         b->backimage->data = (char *) MALLOC( b->backimage->height
624                                             * b->backimage->bytes_per_line );
625         if (!b->backimage->data) {
626            _mesa_warning(NULL, "alloc_back_buffer: MALLOC failed.");
627            XMesaDestroyImage( b->backimage );
628            b->backimage = NULL;
629         }
630      }
631      b->backpixmap = None;
632   }
633   else if (b->db_state==BACK_PIXMAP) {
634      XMesaPixmap old_pixmap = b->backpixmap;
635      /* Free the old back pixmap */
636      if (b->backpixmap) {
637	 XMesaFreePixmap( b->xm_visual->display, b->backpixmap );
638      }
639      /* Allocate new back pixmap */
640      b->backpixmap = XMesaCreatePixmap( b->xm_visual->display, b->frontbuffer,
641					 b->width, b->height,
642					 GET_VISUAL_DEPTH(b->xm_visual) );
643      b->backimage = NULL;
644      /* update other references to backpixmap */
645      if (b->buffer==(XMesaDrawable)old_pixmap) {
646	 b->buffer = (XMesaDrawable)b->backpixmap;
647      }
648   }
649}
650
651
652
653/*
654 * A replacement for XAllocColor.  This function should never
655 * fail to allocate a color.  When XAllocColor fails, we return
656 * the nearest matching color.  If we have to allocate many colors
657 * this function isn't too efficient; the XQueryColors() could be
658 * done just once.
659 * Written by Michael Pichler, Brian Paul, Mark Kilgard
660 * Input:  dpy - X display
661 *         cmap - X colormap
662 *         cmapSize - size of colormap
663 * In/Out: color - the XColor struct
664 * Output:  exact - 1=exact color match, 0=closest match
665 *          alloced - 1=XAlloc worked, 0=XAlloc failed
666 */
667static void
668noFaultXAllocColor( int client,
669                    XMesaDisplay *dpy,
670                    XMesaColormap cmap,
671                    int cmapSize,
672                    XMesaColor *color,
673                    int *exact, int *alloced )
674{
675#ifdef XFree86Server
676   Pixel *ppixIn;
677   xrgb *ctable;
678#else
679   /* we'll try to cache ctable for better remote display performance */
680   static Display *prevDisplay = NULL;
681   static XMesaColormap prevCmap = 0;
682   static int prevCmapSize = 0;
683   static XMesaColor *ctable = NULL;
684#endif
685   XMesaColor subColor;
686   int i, bestmatch;
687   double mindist;       /* 3*2^16^2 exceeds long int precision. */
688
689   (void) client;
690
691   /* First try just using XAllocColor. */
692#ifdef XFree86Server
693   if (AllocColor(cmap,
694		  &color->red, &color->green, &color->blue,
695		  &color->pixel,
696		  client) == Success) {
697#else
698   if (XAllocColor(dpy, cmap, color)) {
699#endif
700      *exact = 1;
701      *alloced = 1;
702      return;
703   }
704
705   /* Alloc failed, search for closest match */
706
707   /* Retrieve color table entries. */
708   /* XXX alloca candidate. */
709#ifdef XFree86Server
710   ppixIn = (Pixel *) MALLOC(cmapSize * sizeof(Pixel));
711   ctable = (xrgb *) MALLOC(cmapSize * sizeof(xrgb));
712   for (i = 0; i < cmapSize; i++) {
713      ppixIn[i] = i;
714   }
715   QueryColors(cmap, cmapSize, ppixIn, ctable);
716#else
717   if (prevDisplay != dpy || prevCmap != cmap
718       || prevCmapSize != cmapSize || !ctable) {
719      /* free previously cached color table */
720      if (ctable)
721         FREE(ctable);
722      /* Get the color table from X */
723      ctable = (XMesaColor *) MALLOC(cmapSize * sizeof(XMesaColor));
724      assert(ctable);
725      for (i = 0; i < cmapSize; i++) {
726         ctable[i].pixel = i;
727      }
728      XQueryColors(dpy, cmap, ctable, cmapSize);
729      prevDisplay = dpy;
730      prevCmap = cmap;
731      prevCmapSize = cmapSize;
732   }
733#endif
734
735   /* Find best match. */
736   bestmatch = -1;
737   mindist = 0.0;
738   for (i = 0; i < cmapSize; i++) {
739      double dr = 0.30 * ((double) color->red - (double) ctable[i].red);
740      double dg = 0.59 * ((double) color->green - (double) ctable[i].green);
741      double db = 0.11 * ((double) color->blue - (double) ctable[i].blue);
742      double dist = dr * dr + dg * dg + db * db;
743      if (bestmatch < 0 || dist < mindist) {
744         bestmatch = i;
745         mindist = dist;
746      }
747   }
748
749   /* Return result. */
750   subColor.red   = ctable[bestmatch].red;
751   subColor.green = ctable[bestmatch].green;
752   subColor.blue  = ctable[bestmatch].blue;
753   /* Try to allocate the closest match color.  This should only
754    * fail if the cell is read/write.  Otherwise, we're incrementing
755    * the cell's reference count.
756    */
757#ifdef XFree86Server
758   if (AllocColor(cmap,
759		  &subColor.red, &subColor.green, &subColor.blue,
760		  &subColor.pixel,
761		  client) == Success) {
762#else
763   if (XAllocColor(dpy, cmap, &subColor)) {
764#endif
765      *alloced = 1;
766   }
767   else {
768      /* do this to work around a problem reported by Frank Ortega */
769      subColor.pixel = (unsigned long) bestmatch;
770      subColor.red   = ctable[bestmatch].red;
771      subColor.green = ctable[bestmatch].green;
772      subColor.blue  = ctable[bestmatch].blue;
773      subColor.flags = DoRed | DoGreen | DoBlue;
774      *alloced = 0;
775   }
776#ifdef XFree86Server
777   FREE(ppixIn);
778   FREE(ctable);
779#else
780   /* don't free table, save it for next time */
781#endif
782
783   *color = subColor;
784   *exact = 0;
785}
786
787
788
789
790/*
791 * Do setup for PF_GRAYSCALE pixel format.
792 * Note that buffer may be NULL.
793 */
794static GLboolean setup_grayscale( int client, XMesaVisual v,
795                                  XMesaBuffer buffer, XMesaColormap cmap )
796{
797   if (GET_VISUAL_DEPTH(v)<4 || GET_VISUAL_DEPTH(v)>16) {
798      return GL_FALSE;
799   }
800
801   if (buffer) {
802      XMesaBuffer prevBuffer;
803
804      if (!cmap) {
805         return GL_FALSE;
806      }
807
808      prevBuffer = find_xmesa_buffer(v->display, cmap, buffer);
809      if (prevBuffer &&
810          (buffer->xm_visual->mesa_visual.rgbMode ==
811           prevBuffer->xm_visual->mesa_visual.rgbMode)) {
812         /* Copy colormap stuff from previous XMesaBuffer which uses same
813          * X colormap.  Do this to avoid time spent in noFaultXAllocColor.
814          */
815         copy_colortable_info(buffer, prevBuffer);
816      }
817      else {
818         /* Allocate 256 shades of gray */
819         int gray;
820         int colorsfailed = 0;
821         for (gray=0;gray<256;gray++) {
822            GLint r = gamma_adjust( v->RedGamma,   gray, 255 );
823            GLint g = gamma_adjust( v->GreenGamma, gray, 255 );
824            GLint b = gamma_adjust( v->BlueGamma,  gray, 255 );
825            int exact, alloced;
826            XMesaColor xcol;
827            xcol.red   = (r << 8) | r;
828            xcol.green = (g << 8) | g;
829            xcol.blue  = (b << 8) | b;
830            noFaultXAllocColor( client, v->display,
831                                cmap, GET_COLORMAP_SIZE(v),
832                                &xcol, &exact, &alloced );
833            if (!exact) {
834               colorsfailed++;
835            }
836            if (alloced) {
837               assert(buffer->num_alloced<256);
838               buffer->alloced_colors[buffer->num_alloced] = xcol.pixel;
839               buffer->num_alloced++;
840            }
841
842            /*OLD
843            assert(gray < 576);
844            buffer->color_table[gray*3+0] = xcol.pixel;
845            buffer->color_table[gray*3+1] = xcol.pixel;
846            buffer->color_table[gray*3+2] = xcol.pixel;
847            assert(xcol.pixel < 65536);
848            buffer->pixel_to_r[xcol.pixel] = gray * 30 / 100;
849            buffer->pixel_to_g[xcol.pixel] = gray * 59 / 100;
850            buffer->pixel_to_b[xcol.pixel] = gray * 11 / 100;
851            */
852            buffer->color_table[gray] = xcol.pixel;
853            assert(xcol.pixel < 65536);
854            buffer->pixel_to_r[xcol.pixel] = gray;
855            buffer->pixel_to_g[xcol.pixel] = gray;
856            buffer->pixel_to_b[xcol.pixel] = gray;
857         }
858
859         if (colorsfailed && _mesa_getenv("MESA_DEBUG")) {
860            _mesa_warning(NULL,
861                  "Note: %d out of 256 needed colors do not match exactly.\n",
862                  colorsfailed );
863         }
864      }
865   }
866
867   v->dithered_pf = PF_Grayscale;
868   v->undithered_pf = PF_Grayscale;
869   return GL_TRUE;
870}
871
872
873
874/*
875 * Setup RGB rendering for a window with a PseudoColor, StaticColor,
876 * or 8-bit TrueColor visual visual.  We try to allocate a palette of 225
877 * colors (5 red, 9 green, 5 blue) and dither to approximate a 24-bit RGB
878 * color.  While this function was originally designed just for 8-bit
879 * visuals, it has also proven to work from 4-bit up to 16-bit visuals.
880 * Dithering code contributed by Bob Mercier.
881 */
882static GLboolean setup_dithered_color( int client, XMesaVisual v,
883                                       XMesaBuffer buffer, XMesaColormap cmap )
884{
885   if (GET_VISUAL_DEPTH(v)<4 || GET_VISUAL_DEPTH(v)>16) {
886      return GL_FALSE;
887   }
888
889   if (buffer) {
890      XMesaBuffer prevBuffer;
891
892      if (!cmap) {
893         return GL_FALSE;
894      }
895
896      prevBuffer = find_xmesa_buffer(v->display, cmap, buffer);
897      if (prevBuffer &&
898          (buffer->xm_visual->mesa_visual.rgbMode ==
899           prevBuffer->xm_visual->mesa_visual.rgbMode)) {
900         /* Copy colormap stuff from previous, matching XMesaBuffer.
901          * Do this to avoid time spent in noFaultXAllocColor.
902          */
903         copy_colortable_info(buffer, prevBuffer);
904      }
905      else {
906         /* Allocate X colors and initialize color_table[], red_table[], etc */
907         int r, g, b, i;
908         int colorsfailed = 0;
909         for (r = 0; r < DITH_R; r++) {
910            for (g = 0; g < DITH_G; g++) {
911               for (b = 0; b < DITH_B; b++) {
912                  XMesaColor xcol;
913                  int exact, alloced;
914                  xcol.red  =gamma_adjust(v->RedGamma,   r*65535/(DITH_R-1),65535);
915                  xcol.green=gamma_adjust(v->GreenGamma, g*65535/(DITH_G-1),65535);
916                  xcol.blue =gamma_adjust(v->BlueGamma,  b*65535/(DITH_B-1),65535);
917                  noFaultXAllocColor( client, v->display,
918                                      cmap, GET_COLORMAP_SIZE(v),
919                                      &xcol, &exact, &alloced );
920                  if (!exact) {
921                     colorsfailed++;
922                  }
923                  if (alloced) {
924                     assert(buffer->num_alloced<256);
925                     buffer->alloced_colors[buffer->num_alloced] = xcol.pixel;
926                     buffer->num_alloced++;
927                  }
928                  i = DITH_MIX( r, g, b );
929                  assert(i < 576);
930                  buffer->color_table[i] = xcol.pixel;
931                  assert(xcol.pixel < 65536);
932                  buffer->pixel_to_r[xcol.pixel] = r * 255 / (DITH_R-1);
933                  buffer->pixel_to_g[xcol.pixel] = g * 255 / (DITH_G-1);
934                  buffer->pixel_to_b[xcol.pixel] = b * 255 / (DITH_B-1);
935               }
936            }
937         }
938
939         if (colorsfailed && _mesa_getenv("MESA_DEBUG")) {
940            _mesa_warning(NULL,
941                  "Note: %d out of %d needed colors do not match exactly.\n",
942                  colorsfailed, DITH_R * DITH_G * DITH_B );
943         }
944      }
945   }
946
947   v->dithered_pf = PF_Dither;
948   v->undithered_pf = PF_Lookup;
949   return GL_TRUE;
950}
951
952
953/*
954 * Setup for Hewlett Packard Color Recovery 8-bit TrueColor mode.
955 * HPCR simulates 24-bit color fidelity with an 8-bit frame buffer.
956 * Special dithering tables have to be initialized.
957 */
958static void setup_8bit_hpcr( XMesaVisual v )
959{
960   /* HP Color Recovery contributed by:  Alex De Bruyn (ad@lms.be)
961    * To work properly, the atom _HP_RGB_SMOOTH_MAP_LIST must be defined
962    * on the root window AND the colormap obtainable by XGetRGBColormaps
963    * for that atom must be set on the window.  (see also tkInitWindow)
964    * If that colormap is not set, the output will look stripy.
965    */
966
967   /* Setup color tables with gamma correction */
968   int i;
969   double g;
970
971   g = 1.0 / v->RedGamma;
972   for (i=0; i<256; i++) {
973      GLint red = IROUND_POS(255.0 * _mesa_pow( hpcr_rgbTbl[0][i]/255.0, g ));
974      v->hpcr_rgbTbl[0][i] = CLAMP( red, 16, 239 );
975   }
976
977   g = 1.0 / v->GreenGamma;
978   for (i=0; i<256; i++) {
979      GLint green = IROUND_POS(255.0 * _mesa_pow( hpcr_rgbTbl[1][i]/255.0, g ));
980      v->hpcr_rgbTbl[1][i] = CLAMP( green, 16, 239 );
981   }
982
983   g = 1.0 / v->BlueGamma;
984   for (i=0; i<256; i++) {
985      GLint blue = IROUND_POS(255.0 * _mesa_pow( hpcr_rgbTbl[2][i]/255.0, g ));
986      v->hpcr_rgbTbl[2][i] = CLAMP( blue, 32, 223 );
987   }
988   v->undithered_pf = PF_HPCR;  /* can't really disable dithering for now */
989   v->dithered_pf = PF_HPCR;
990
991   /* which method should I use to clear */
992   /* GL_FALSE: keep the ordinary method  */
993   /* GL_TRUE : clear with dither pattern */
994   v->hpcr_clear_flag = _mesa_getenv("MESA_HPCR_CLEAR") ? GL_TRUE : GL_FALSE;
995
996   if (v->hpcr_clear_flag) {
997      v->hpcr_clear_pixmap = XMesaCreatePixmap(v->display,
998                                               DefaultRootWindow(v->display),
999                                               16, 2, 8);
1000#ifndef XFree86Server
1001      v->hpcr_clear_ximage = XGetImage(v->display, v->hpcr_clear_pixmap,
1002                                       0, 0, 16, 2, AllPlanes, ZPixmap);
1003#endif
1004   }
1005}
1006
1007
1008/*
1009 * Setup RGB rendering for a window with a True/DirectColor visual.
1010 */
1011static void setup_truecolor( XMesaVisual v, XMesaBuffer buffer,
1012                             XMesaColormap cmap )
1013{
1014   unsigned long rmask, gmask, bmask;
1015   (void) buffer;
1016   (void) cmap;
1017
1018   /* Compute red multiplier (mask) and bit shift */
1019   v->rshift = 0;
1020   rmask = GET_REDMASK(v);
1021   while ((rmask & 1)==0) {
1022      v->rshift++;
1023      rmask = rmask >> 1;
1024   }
1025
1026   /* Compute green multiplier (mask) and bit shift */
1027   v->gshift = 0;
1028   gmask = GET_GREENMASK(v);
1029   while ((gmask & 1)==0) {
1030      v->gshift++;
1031      gmask = gmask >> 1;
1032   }
1033
1034   /* Compute blue multiplier (mask) and bit shift */
1035   v->bshift = 0;
1036   bmask = GET_BLUEMASK(v);
1037   while ((bmask & 1)==0) {
1038      v->bshift++;
1039      bmask = bmask >> 1;
1040   }
1041
1042   /*
1043    * Compute component-to-pixel lookup tables and dithering kernel
1044    */
1045   {
1046      static GLubyte kernel[16] = {
1047          0*16,  8*16,  2*16, 10*16,
1048         12*16,  4*16, 14*16,  6*16,
1049          3*16, 11*16,  1*16,  9*16,
1050         15*16,  7*16, 13*16,  5*16,
1051      };
1052      GLint rBits = bitcount(rmask);
1053      GLint gBits = bitcount(gmask);
1054      GLint bBits = bitcount(bmask);
1055      GLint maxBits;
1056      GLuint i;
1057
1058      /* convert pixel components in [0,_mask] to RGB values in [0,255] */
1059      for (i=0; i<=rmask; i++)
1060         v->PixelToR[i] = (unsigned char) ((i * 255) / rmask);
1061      for (i=0; i<=gmask; i++)
1062         v->PixelToG[i] = (unsigned char) ((i * 255) / gmask);
1063      for (i=0; i<=bmask; i++)
1064         v->PixelToB[i] = (unsigned char) ((i * 255) / bmask);
1065
1066      /* convert RGB values from [0,255] to pixel components */
1067
1068      for (i=0;i<256;i++) {
1069         GLint r = gamma_adjust(v->RedGamma,   i, 255);
1070         GLint g = gamma_adjust(v->GreenGamma, i, 255);
1071         GLint b = gamma_adjust(v->BlueGamma,  i, 255);
1072         v->RtoPixel[i] = (r >> (8-rBits)) << v->rshift;
1073         v->GtoPixel[i] = (g >> (8-gBits)) << v->gshift;
1074         v->BtoPixel[i] = (b >> (8-bBits)) << v->bshift;
1075      }
1076      /* overflow protection */
1077      for (i=256;i<512;i++) {
1078         v->RtoPixel[i] = v->RtoPixel[255];
1079         v->GtoPixel[i] = v->GtoPixel[255];
1080         v->BtoPixel[i] = v->BtoPixel[255];
1081      }
1082
1083      /* setup dithering kernel */
1084      maxBits = rBits;
1085      if (gBits > maxBits)  maxBits = gBits;
1086      if (bBits > maxBits)  maxBits = bBits;
1087      for (i=0;i<16;i++) {
1088         v->Kernel[i] = kernel[i] >> maxBits;
1089      }
1090
1091      v->undithered_pf = PF_Truecolor;
1092      v->dithered_pf = (GET_VISUAL_DEPTH(v)<24) ? PF_Dither_True : PF_Truecolor;
1093   }
1094
1095   /*
1096    * Now check for TrueColor visuals which we can optimize.
1097    */
1098   if (   GET_REDMASK(v)  ==0x0000ff
1099       && GET_GREENMASK(v)==0x00ff00
1100       && GET_BLUEMASK(v) ==0xff0000
1101       && CHECK_BYTE_ORDER(v)
1102       && v->BitsPerPixel==32
1103       && sizeof(GLuint)==4
1104       && v->RedGamma==1.0 && v->GreenGamma==1.0 && v->BlueGamma==1.0) {
1105      /* common 32 bpp config used on SGI, Sun */
1106      v->undithered_pf = v->dithered_pf = PF_8A8B8G8R;
1107   }
1108   else if (GET_REDMASK(v)  ==0xff0000
1109       &&   GET_GREENMASK(v)==0x00ff00
1110       &&   GET_BLUEMASK(v) ==0x0000ff
1111       && CHECK_BYTE_ORDER(v)
1112       && v->BitsPerPixel==32
1113       && sizeof(GLuint)==4
1114       && v->RedGamma==1.0 && v->GreenGamma==1.0 && v->BlueGamma==1.0) {
1115      /* common 32 bpp config used on Linux, HP, IBM */
1116      v->undithered_pf = v->dithered_pf = PF_8R8G8B;
1117   }
1118   else if (GET_REDMASK(v)  ==0xff0000
1119       &&   GET_GREENMASK(v)==0x00ff00
1120       &&   GET_BLUEMASK(v) ==0x0000ff
1121       && CHECK_BYTE_ORDER(v)
1122       && v->BitsPerPixel==24
1123       && sizeof(GLuint)==4
1124       && v->RedGamma==1.0 && v->GreenGamma==1.0 && v->BlueGamma==1.0) {
1125      /* common packed 24 bpp config used on Linux */
1126      v->undithered_pf = v->dithered_pf = PF_8R8G8B24;
1127   }
1128   else if (GET_REDMASK(v)  ==0xf800
1129       &&   GET_GREENMASK(v)==0x07e0
1130       &&   GET_BLUEMASK(v) ==0x001f
1131       && CHECK_BYTE_ORDER(v)
1132       && v->BitsPerPixel==16
1133       && sizeof(GLushort)==2
1134       && v->RedGamma==1.0 && v->GreenGamma==1.0 && v->BlueGamma==1.0) {
1135      /* 5-6-5 color weight on common PC VGA boards */
1136      v->undithered_pf = PF_5R6G5B;
1137      v->dithered_pf = PF_Dither_5R6G5B;
1138   }
1139   else if (GET_REDMASK(v)  ==0xe0
1140       &&   GET_GREENMASK(v)==0x1c
1141       &&   GET_BLUEMASK(v) ==0x03
1142       && CHECK_FOR_HPCR(v)) {
1143      setup_8bit_hpcr( v );
1144   }
1145}
1146
1147
1148
1149/*
1150 * Setup RGB rendering for a window with a monochrome visual.
1151 */
1152static void setup_monochrome( XMesaVisual v, XMesaBuffer b )
1153{
1154   (void) b;
1155   v->dithered_pf = v->undithered_pf = PF_1Bit;
1156   /* if black=1 then we must flip pixel values */
1157   v->bitFlip = (GET_BLACK_PIXEL(v) != 0);
1158}
1159
1160
1161
1162/*
1163 * When a context is "made current" for the first time, we can finally
1164 * finish initializing the context's visual and buffer information.
1165 * Input:  v - the XMesaVisual to initialize
1166 *         b - the XMesaBuffer to initialize (may be NULL)
1167 *         rgb_flag - TRUE = RGBA mode, FALSE = color index mode
1168 *         window - the window/pixmap we're rendering into
1169 *         cmap - the colormap associated with the window/pixmap
1170 * Return:  GL_TRUE=success, GL_FALSE=failure
1171 */
1172static GLboolean initialize_visual_and_buffer( int client,
1173                                               XMesaVisual v,
1174                                               XMesaBuffer b,
1175                                               GLboolean rgb_flag,
1176                                               XMesaDrawable window,
1177                                               XMesaColormap cmap )
1178{
1179#ifndef XFree86Server
1180   XGCValues gcvalues;
1181#endif
1182
1183   if (b) {
1184      assert(b->xm_visual == v);
1185   }
1186
1187   /* Save true bits/pixel */
1188   v->BitsPerPixel = bits_per_pixel(v);
1189   assert(v->BitsPerPixel > 0);
1190
1191
1192   if (rgb_flag==GL_FALSE) {
1193      /* COLOR-INDEXED WINDOW:
1194       * Even if the visual is TrueColor or DirectColor we treat it as
1195       * being color indexed.  This is weird but might be useful to someone.
1196       */
1197      v->dithered_pf = v->undithered_pf = PF_Index;
1198      v->index_bits = GET_VISUAL_DEPTH(v);
1199   }
1200   else {
1201      /* RGB WINDOW:
1202       * We support RGB rendering into almost any kind of visual.
1203       */
1204      int xclass;
1205      xclass = GET_VISUAL_CLASS(v);
1206      if (xclass==TrueColor || xclass==DirectColor) {
1207	 setup_truecolor( v, b, cmap );
1208      }
1209      else if (xclass==StaticGray && GET_VISUAL_DEPTH(v)==1) {
1210	 setup_monochrome( v, b );
1211      }
1212      else if (xclass==GrayScale || xclass==StaticGray) {
1213         if (!setup_grayscale( client, v, b, cmap )) {
1214            return GL_FALSE;
1215         }
1216      }
1217      else if ((xclass==PseudoColor || xclass==StaticColor)
1218               && GET_VISUAL_DEPTH(v)>=4 && GET_VISUAL_DEPTH(v)<=16) {
1219	 if (!setup_dithered_color( client, v, b, cmap )) {
1220            return GL_FALSE;
1221         }
1222      }
1223      else {
1224	 _mesa_warning(NULL, "XMesa: RGB mode rendering not supported in given visual.");
1225	 return GL_FALSE;
1226      }
1227      v->index_bits = 0;
1228
1229      if (_mesa_getenv("MESA_NO_DITHER")) {
1230	 v->dithered_pf = v->undithered_pf;
1231      }
1232   }
1233
1234
1235   /*
1236    * If MESA_INFO env var is set print out some debugging info
1237    * which can help Brian figure out what's going on when a user
1238    * reports bugs.
1239    */
1240   if (_mesa_getenv("MESA_INFO")) {
1241      _mesa_printf("X/Mesa visual = %p\n", (void *) v);
1242      _mesa_printf("X/Mesa dithered pf = %u\n", v->dithered_pf);
1243      _mesa_printf("X/Mesa undithered pf = %u\n", v->undithered_pf);
1244      _mesa_printf("X/Mesa level = %d\n", v->level);
1245      _mesa_printf("X/Mesa depth = %d\n", GET_VISUAL_DEPTH(v));
1246      _mesa_printf("X/Mesa bits per pixel = %d\n", v->BitsPerPixel);
1247   }
1248
1249   if (b && window) {
1250      /* Do window-specific initializations */
1251
1252      /* Window dimensions */
1253      unsigned int w, h;
1254      get_drawable_size( v->display, window, &w, &h );
1255      b->width = w;
1256      b->height = h;
1257
1258      b->frontbuffer = window;
1259
1260      /* Setup for single/double buffering */
1261      if (v->mesa_visual.doubleBufferMode) {
1262         /* Double buffered */
1263#ifndef XFree86Server
1264         b->shm = check_for_xshm( v->display );
1265#endif
1266         xmesa_alloc_back_buffer( b );
1267         if (b->db_state==BACK_PIXMAP) {
1268            b->buffer = (XMesaDrawable)b->backpixmap;
1269         }
1270         else {
1271            b->buffer = XIMAGE;
1272         }
1273      }
1274      else {
1275         /* Single Buffered */
1276         b->buffer = b->frontbuffer;
1277      }
1278
1279      /* X11 graphics contexts */
1280#ifdef XFree86Server
1281      b->gc = CreateScratchGC(v->display, window->depth);
1282#else
1283      b->gc = XCreateGC( v->display, window, 0, NULL );
1284#endif
1285      XMesaSetFunction( v->display, b->gc, GXcopy );
1286
1287      /* cleargc - for glClear() */
1288#ifdef XFree86Server
1289      b->cleargc = CreateScratchGC(v->display, window->depth);
1290#else
1291      b->cleargc = XCreateGC( v->display, window, 0, NULL );
1292#endif
1293      XMesaSetFunction( v->display, b->cleargc, GXcopy );
1294
1295      /*
1296       * Don't generate Graphics Expose/NoExpose events in swapbuffers().
1297       * Patch contributed by Michael Pichler May 15, 1995.
1298       */
1299#ifdef XFree86Server
1300      b->swapgc = CreateScratchGC(v->display, window->depth);
1301      {
1302	  CARD32 v[1];
1303	  v[0] = FALSE;
1304	  dixChangeGC(NullClient, b->swapgc, GCGraphicsExposures, v, NULL);
1305      }
1306#else
1307      gcvalues.graphics_exposures = False;
1308      b->swapgc = XCreateGC( v->display, window,
1309                              GCGraphicsExposures, &gcvalues);
1310#endif
1311      XMesaSetFunction( v->display, b->swapgc, GXcopy );
1312      /*
1313       * Set fill style and tile pixmap once for all for HPCR stuff
1314       * (instead of doing it each time in clear_color_HPCR_pixmap())
1315       * Initialize whole stuff
1316       * Patch contributed by Jacques Leroy March 8, 1998.
1317       */
1318      if (v->hpcr_clear_flag && b->buffer!=XIMAGE) {
1319	int i;
1320	for (i=0; i<16; i++)
1321        {
1322	   XMesaPutPixel(v->hpcr_clear_ximage, i, 0, 0);
1323	   XMesaPutPixel(v->hpcr_clear_ximage, i, 1, 0);
1324        }
1325        XMesaPutImage(b->display, (XMesaDrawable)v->hpcr_clear_pixmap,
1326		      b->cleargc, v->hpcr_clear_ximage, 0, 0, 0, 0, 16, 2);
1327	XMesaSetFillStyle( v->display, b->cleargc, FillTiled);
1328	XMesaSetTile( v->display, b->cleargc, v->hpcr_clear_pixmap );
1329      }
1330
1331      /* Initialize the row buffer XImage for use in write_color_span() */
1332#ifdef XFree86Server
1333      b->rowimage = XMesaCreateImage(GET_VISUAL_DEPTH(v), MAX_WIDTH, 1,
1334				     (char *)MALLOC(MAX_WIDTH*4));
1335#else
1336      b->rowimage = XCreateImage( v->display,
1337                                  v->visinfo->visual,
1338                                  v->visinfo->depth,
1339                                  ZPixmap, 0,           /*format, offset*/
1340                                  (char*) MALLOC(MAX_WIDTH*4),  /*data*/
1341                                  MAX_WIDTH, 1,         /*width, height*/
1342                                  32,                   /*bitmap_pad*/
1343                                  0                     /*bytes_per_line*/ );
1344#endif
1345   }
1346
1347   return GL_TRUE;
1348}
1349
1350
1351
1352/*
1353 * Convert an RGBA color to a pixel value.
1354 */
1355unsigned long
1356xmesa_color_to_pixel( XMesaContext xmesa, GLubyte r, GLubyte g, GLubyte b, GLubyte a,
1357                      GLuint pixelFormat)
1358{
1359   switch (pixelFormat) {
1360      case PF_Index:
1361         return 0;
1362      case PF_Truecolor:
1363         {
1364            unsigned long p;
1365            PACK_TRUECOLOR( p, r, g, b );
1366            return p;
1367         }
1368      case PF_8A8B8G8R:
1369         return PACK_8A8B8G8R( r, g, b, a );
1370      case PF_8R8G8B:
1371         /* fall through */
1372      case PF_8R8G8B24:
1373         return PACK_8R8G8B( r, g, b );
1374      case PF_5R6G5B:
1375         return PACK_5R6G5B( r, g, b );
1376      case PF_Dither:
1377         {
1378            DITHER_SETUP;
1379            return DITHER( 1, 0, r, g, b );
1380         }
1381      case PF_1Bit:
1382         /* 382 = (3*255)/2 */
1383         return ((r+g+b) > 382) ^ xmesa->xm_visual->bitFlip;
1384      case PF_HPCR:
1385         return DITHER_HPCR(1, 1, r, g, b);
1386      case PF_Lookup:
1387         {
1388            LOOKUP_SETUP;
1389            return LOOKUP( r, g, b );
1390         }
1391      case PF_Grayscale:
1392         return GRAY_RGB( r, g, b );
1393      case PF_Dither_True:
1394         /* fall through */
1395      case PF_Dither_5R6G5B:
1396         {
1397            unsigned long p;
1398            PACK_TRUEDITHER(p, 1, 0, r, g, b);
1399            return p;
1400         }
1401      default:
1402         _mesa_problem(NULL, "Bad pixel format in xmesa_color_to_pixel");
1403   }
1404   return 0;
1405}
1406
1407
1408/**********************************************************************/
1409/*****                       Public Functions                     *****/
1410/**********************************************************************/
1411
1412
1413/*
1414 * Create a new X/Mesa visual.
1415 * Input:  display - X11 display
1416 *         visinfo - an XVisualInfo pointer
1417 *         rgb_flag - GL_TRUE = RGB mode,
1418 *                    GL_FALSE = color index mode
1419 *         alpha_flag - alpha buffer requested?
1420 *         db_flag - GL_TRUE = double-buffered,
1421 *                   GL_FALSE = single buffered
1422 *         stereo_flag - stereo visual?
1423 *         ximage_flag - GL_TRUE = use an XImage for back buffer,
1424 *                       GL_FALSE = use an off-screen pixmap for back buffer
1425 *         depth_size - requested bits/depth values, or zero
1426 *         stencil_size - requested bits/stencil values, or zero
1427 *         accum_red_size - requested bits/red accum values, or zero
1428 *         accum_green_size - requested bits/green accum values, or zero
1429 *         accum_blue_size - requested bits/blue accum values, or zero
1430 *         accum_alpha_size - requested bits/alpha accum values, or zero
1431 *         num_samples - number of samples/pixel if multisampling, or zero
1432 *         level - visual level, usually 0
1433 *         visualCaveat - ala the GLX extension, usually GLX_NONE_EXT
1434 * Return;  a new XMesaVisual or 0 if error.
1435 */
1436XMesaVisual XMesaCreateVisual( XMesaDisplay *display,
1437                               XMesaVisualInfo visinfo,
1438                               GLboolean rgb_flag,
1439                               GLboolean alpha_flag,
1440                               GLboolean db_flag,
1441                               GLboolean stereo_flag,
1442                               GLboolean ximage_flag,
1443                               GLint depth_size,
1444                               GLint stencil_size,
1445                               GLint accum_red_size,
1446                               GLint accum_green_size,
1447                               GLint accum_blue_size,
1448                               GLint accum_alpha_size,
1449                               GLint num_samples,
1450                               GLint level,
1451                               GLint visualCaveat )
1452{
1453   char *gamma;
1454   XMesaVisual v;
1455   GLint red_bits, green_bits, blue_bits, alpha_bits;
1456
1457   /* For debugging only */
1458   if (_mesa_getenv("MESA_XSYNC")) {
1459      /* This makes debugging X easier.
1460       * In your debugger, set a breakpoint on _XError to stop when an
1461       * X protocol error is generated.
1462       */
1463#ifdef XFree86Server
1464      /* NOT_NEEDED */
1465#else
1466      XSynchronize( display, 1 );
1467#endif
1468   }
1469
1470   v = (XMesaVisual) CALLOC_STRUCT(xmesa_visual);
1471   if (!v) {
1472      return NULL;
1473   }
1474
1475   /*
1476    * In the X server, NULL is passed in for the display.  It will have
1477    * to be set before using this visual.  See XMesaSetVisualDisplay()
1478    * below.
1479    */
1480   v->display = display;
1481
1482   /* Save a copy of the XVisualInfo struct because the user may XFREE()
1483    * the struct but we may need some of the information contained in it
1484    * at a later time.
1485    */
1486#ifdef XFree86Server
1487   v->visinfo = visinfo;
1488#else
1489   v->visinfo = (XVisualInfo *) MALLOC(sizeof(*visinfo));
1490   if(!v->visinfo) {
1491      FREE(v);
1492      return NULL;
1493   }
1494   MEMCPY(v->visinfo, visinfo, sizeof(*visinfo));
1495#endif
1496
1497#ifdef XFree86Server
1498   /* Initialize the depth of the screen */
1499   {
1500       PixmapFormatRec *format;
1501
1502       for (format = screenInfo.formats;
1503	    format->depth != display->rootDepth;
1504	    format++)
1505	   ;
1506       v->screen_depth = format->bitsPerPixel;
1507   }
1508#endif
1509
1510   /* check for MESA_GAMMA environment variable */
1511   gamma = _mesa_getenv("MESA_GAMMA");
1512   if (gamma) {
1513      v->RedGamma = v->GreenGamma = v->BlueGamma = 0.0;
1514      sscanf( gamma, "%f %f %f", &v->RedGamma, &v->GreenGamma, &v->BlueGamma );
1515      if (v->RedGamma<=0.0)    v->RedGamma = 1.0;
1516      if (v->GreenGamma<=0.0)  v->GreenGamma = v->RedGamma;
1517      if (v->BlueGamma<=0.0)   v->BlueGamma = v->RedGamma;
1518   }
1519   else {
1520      v->RedGamma = v->GreenGamma = v->BlueGamma = 1.0;
1521   }
1522
1523   v->ximage_flag = ximage_flag;
1524   v->level = level;
1525   v->VisualCaveat = visualCaveat;
1526
1527   (void) initialize_visual_and_buffer( 0, v, NULL, rgb_flag, 0, 0 );
1528
1529   {
1530      int xclass;
1531      xclass = GET_VISUAL_CLASS(v);
1532      if (xclass==TrueColor || xclass==DirectColor) {
1533         red_bits   = bitcount(GET_REDMASK(v));
1534         green_bits = bitcount(GET_GREENMASK(v));
1535         blue_bits  = bitcount(GET_BLUEMASK(v));
1536         alpha_bits = 0;
1537      }
1538      else {
1539         /* this is an approximation */
1540         int depth;
1541         depth = GET_VISUAL_DEPTH(v);
1542         red_bits = depth / 3;
1543         depth -= red_bits;
1544         green_bits = depth / 2;
1545         depth -= green_bits;
1546         blue_bits = depth;
1547         alpha_bits = 0;
1548         assert( red_bits + green_bits + blue_bits == GET_VISUAL_DEPTH(v) );
1549      }
1550   }
1551
1552   if (alpha_flag && alpha_bits == 0)
1553      alpha_bits = 8;
1554
1555   _mesa_initialize_visual( &v->mesa_visual,
1556                            rgb_flag, db_flag, stereo_flag,
1557                            red_bits, green_bits,
1558                            blue_bits, alpha_bits,
1559                            v->index_bits,
1560                            depth_size,
1561                            stencil_size,
1562                            accum_red_size, accum_green_size,
1563                            accum_blue_size, accum_alpha_size,
1564                            0 );
1565   return v;
1566}
1567
1568
1569void XMesaSetVisualDisplay( XMesaDisplay *dpy, XMesaVisual v )
1570{
1571    v->display = dpy;
1572}
1573
1574
1575void XMesaDestroyVisual( XMesaVisual v )
1576{
1577#ifndef XFree86Server
1578   FREE(v->visinfo);
1579#endif
1580   FREE(v);
1581}
1582
1583
1584
1585/*
1586 * Create a new XMesaContext.
1587 * Input:  v - XMesaVisual
1588 *         share_list - another XMesaContext with which to share display
1589 *                      lists or NULL if no sharing is wanted.
1590 * Return:  an XMesaContext or NULL if error.
1591 */
1592XMesaContext XMesaCreateContext( XMesaVisual v, XMesaContext share_list )
1593{
1594   static GLboolean firstTime = GL_TRUE;
1595   XMesaContext c;
1596   GLboolean direct = GL_TRUE; /* not really */
1597   GLcontext *mesaCtx;
1598
1599   if (firstTime) {
1600      _glthread_INIT_MUTEX(_xmesa_lock);
1601      firstTime = GL_FALSE;
1602   }
1603
1604   c = (XMesaContext) CALLOC_STRUCT(xmesa_context);
1605   if (!c) {
1606      return NULL;
1607   }
1608
1609   mesaCtx = &(c->mesa);
1610
1611   /* Setup these pointers here since they're using for making the default
1612    * and proxy texture objects.  Actually, we don't really need to do
1613    * this since we're using the default fallback functions which
1614    * _mesa_initialize_context() would plug in if needed.
1615    */
1616   mesaCtx->Driver.NewTextureObject = _mesa_new_texture_object;
1617   mesaCtx->Driver.DeleteTexture = _mesa_delete_texture_object;
1618
1619   if (!_mesa_initialize_context(mesaCtx, &v->mesa_visual,
1620                      share_list ? &(share_list->mesa) : (GLcontext *) NULL,
1621                      (void *) c, direct)) {
1622      FREE(c);
1623      return NULL;
1624   }
1625
1626   _mesa_enable_sw_extensions(mesaCtx);
1627   _mesa_enable_1_3_extensions(mesaCtx);
1628   _mesa_enable_1_4_extensions(mesaCtx);
1629
1630   if (CHECK_BYTE_ORDER(v)) {
1631      c->swapbytes = GL_FALSE;
1632   }
1633   else {
1634      c->swapbytes = GL_TRUE;
1635   }
1636
1637   c->xm_visual = v;
1638   c->xm_draw_buffer = NULL;   /* set later by XMesaMakeCurrent */
1639   c->xm_read_buffer = NULL;   /* set later by XMesaMakeCurrent */
1640   c->xm_buffer = NULL;   /* set later by XMesaMakeCurrent */
1641   c->display = v->display;
1642   c->pixelformat = v->dithered_pf;      /* Dithering is enabled by default */
1643
1644   mesaCtx->Driver.UpdateState = xmesa_update_state;
1645
1646   /* Initialize the software rasterizer and helper modules.
1647    */
1648   _swrast_CreateContext( mesaCtx );
1649   _ac_CreateContext( mesaCtx );
1650   _tnl_CreateContext( mesaCtx );
1651   _swsetup_CreateContext( mesaCtx );
1652
1653   xmesa_register_swrast_functions( mesaCtx );
1654
1655   /* Set up some constant pointers:
1656    */
1657   xmesa_init_pointers( mesaCtx );
1658
1659   return c;
1660}
1661
1662
1663
1664
1665void XMesaDestroyContext( XMesaContext c )
1666{
1667   GLcontext *mesaCtx = &c->mesa;
1668#ifdef FX
1669   if (c->xm_draw_buffer && c->xm_buffer->FXctx)
1670      fxMesaDestroyContext(c->xm_draw_buffer->FXctx);
1671#endif
1672   _swsetup_DestroyContext( mesaCtx );
1673   _swrast_DestroyContext( mesaCtx );
1674   _tnl_DestroyContext( mesaCtx );
1675   _ac_DestroyContext( mesaCtx );
1676   _mesa_free_context_data( mesaCtx );
1677   _mesa_free( c );
1678}
1679
1680
1681
1682/*
1683 * XXX this isn't a public function!  It's a hack for the 3Dfx driver.
1684 * Create a new XMesaBuffer from an X window.
1685 * Input:  v - the XMesaVisual
1686 *         w - the window
1687 *         c - the context
1688 * Return:  new XMesaBuffer or NULL if error
1689 */
1690XMesaBuffer XMesaCreateWindowBuffer2( XMesaVisual v, XMesaWindow w,
1691                                      XMesaContext c )
1692{
1693#ifndef XFree86Server
1694   XWindowAttributes attr;
1695#endif
1696#ifdef FX
1697   char *fxEnvVar;
1698#endif
1699   int client = 0;
1700
1701   XMesaBuffer b = alloc_xmesa_buffer();
1702   if (!b) {
1703      return NULL;
1704   }
1705
1706   (void) c;
1707
1708#ifdef XFree86Server
1709   client = CLIENT_ID(((XMesaDrawable)w)->id);
1710#endif
1711
1712   assert(v);
1713
1714#ifdef XFree86Server
1715   if (GET_VISUAL_DEPTH(v) != ((XMesaDrawable)w)->depth) {
1716#else
1717   XGetWindowAttributes( v->display, w, &attr );
1718
1719   if (GET_VISUAL_DEPTH(v) != attr.depth) {
1720#endif
1721      _mesa_warning(NULL, "XMesaCreateWindowBuffer: depth mismatch between visual and window!\n");
1722      return NULL;
1723   }
1724
1725   b->xm_visual = v;
1726   b->type = WINDOW;
1727   b->display = v->display;
1728#ifdef XFree86Server
1729   b->cmap = (ColormapPtr)LookupIDByType(wColormap(w), RT_COLORMAP);
1730#else
1731   if (attr.colormap) {
1732      b->cmap = attr.colormap;
1733   }
1734   else {
1735      _mesa_warning(NULL, "Window %u has no colormap!\n", (unsigned int) w);
1736      /* this is weird, a window w/out a colormap!? */
1737      /* OK, let's just allocate a new one and hope for the best */
1738      b->cmap = XCreateColormap(v->display, w, attr.visual, AllocNone);
1739   }
1740#endif
1741
1742   /* determine back buffer implementation */
1743   if (v->mesa_visual.doubleBufferMode) {
1744      if (v->ximage_flag) {
1745	 b->db_state = BACK_XIMAGE;
1746      }
1747      else {
1748	 b->db_state = BACK_PIXMAP;
1749      }
1750   }
1751   else {
1752      b->db_state = 0;
1753   }
1754
1755   _mesa_initialize_framebuffer(&b->mesa_buffer,
1756                                &v->mesa_visual,
1757                                v->mesa_visual.depthBits > 0,
1758                                v->mesa_visual.stencilBits > 0,
1759                                v->mesa_visual.accumRedBits > 0,
1760                                v->mesa_visual.alphaBits > 0 );
1761
1762   if (!initialize_visual_and_buffer( client, v, b, v->mesa_visual.rgbMode,
1763                                      (XMesaDrawable)w, b->cmap )) {
1764      free_xmesa_buffer(client, b);
1765      return NULL;
1766   }
1767
1768#ifdef FX
1769   fxEnvVar = _mesa_getenv("MESA_GLX_FX");
1770   if (fxEnvVar) {
1771     if (fxEnvVar[0]!='d') {
1772       int attribs[100];
1773       int numAttribs = 0;
1774       int hw;
1775       if (v->mesa_visual.depthBits > 0) {
1776	 attribs[numAttribs++] = FXMESA_DEPTH_SIZE;
1777	 attribs[numAttribs++] = 1;
1778       }
1779       if (v->mesa_visual.doubleBufferMode) {
1780	 attribs[numAttribs++] = FXMESA_DOUBLEBUFFER;
1781       }
1782       if (v->mesa_visual.accumRedBits > 0) {
1783	 attribs[numAttribs++] = FXMESA_ACCUM_SIZE;
1784	 attribs[numAttribs++] = v->mesa_visual.accumRedBits;
1785       }
1786       if (v->mesa_visual.stencilBits > 0) {
1787         attribs[numAttribs++] = FXMESA_STENCIL_SIZE;
1788         attribs[numAttribs++] = v->mesa_visual.stencilBits;
1789       }
1790       if (v->mesa_visual.alphaBits > 0) {
1791         attribs[numAttribs++] = FXMESA_ALPHA_SIZE;
1792         attribs[numAttribs++] = 1;
1793       }
1794       if (1) {
1795#define FXMESA_SHARE_CONTEXT 990099  /* keep in sync with fxapi.c! */
1796         attribs[numAttribs++] = FXMESA_SHARE_CONTEXT;
1797         attribs[numAttribs++] = (int) &(c->mesa);
1798       }
1799       attribs[numAttribs++] = FXMESA_NONE;
1800
1801       if ((hw = fxQueryHardware())==GR_SSTTYPE_VOODOO) {
1802         b->FXctx = fxMesaCreateBestContext(0, b->width, b->height, attribs);
1803         if ((v->undithered_pf!=PF_Index) && (b->backimage)) {
1804	   b->FXisHackUsable = b->FXctx ? GL_TRUE : GL_FALSE;
1805	   if (fxEnvVar[0]=='w' || fxEnvVar[0]=='W')
1806	     b->FXwindowHack = b->FXctx ? GL_TRUE : GL_FALSE;
1807	   else
1808	     b->FXwindowHack = GL_FALSE;
1809         }
1810       }
1811       else {
1812         if (fxEnvVar[0]=='w' || fxEnvVar[0]=='W')
1813	   b->FXctx = fxMesaCreateContext(w, GR_RESOLUTION_NONE,
1814					  GR_REFRESH_75Hz, attribs);
1815         else
1816	   b->FXctx = fxMesaCreateBestContext(0, b->width, b->height, attribs);
1817         b->FXisHackUsable = GL_FALSE;
1818         b->FXwindowHack = GL_FALSE;
1819       }
1820       /*
1821       fprintf(stderr,
1822               "voodoo %d, wid %d height %d hack: usable %d active %d\n",
1823               hw, b->width, b->height, b->FXisHackUsable, b->FXwindowHack);
1824       */
1825     }
1826   }
1827   else {
1828      _mesa_warning(NULL, "WARNING: This Mesa Library includes the Glide driver but\n");
1829      _mesa_warning(NULL, "         you have not defined the MESA_GLX_FX env. var.\n");
1830      _mesa_warning(NULL, "         (check the README.3DFX file for more information).\n\n");
1831      _mesa_warning(NULL, "         you can disable this message with a 'export MESA_GLX_FX=disable'.\n");
1832   }
1833#endif
1834
1835   return b;
1836}
1837
1838
1839XMesaBuffer XMesaCreateWindowBuffer( XMesaVisual v, XMesaWindow w )
1840{
1841   return XMesaCreateWindowBuffer2( v, w, NULL );
1842}
1843
1844
1845/*
1846 * Create a new XMesaBuffer from an X pixmap.
1847 * Input:  v - the XMesaVisual
1848 *         p - the pixmap
1849 *         cmap - the colormap, may be 0 if using a TrueColor or DirectColor
1850 *                visual for the pixmap
1851 * Return:  new XMesaBuffer or NULL if error
1852 */
1853XMesaBuffer XMesaCreatePixmapBuffer( XMesaVisual v,
1854				     XMesaPixmap p, XMesaColormap cmap )
1855{
1856   int client = 0;
1857   XMesaBuffer b = alloc_xmesa_buffer();
1858   if (!b) {
1859      return NULL;
1860   }
1861
1862
1863#ifdef XFree86Server
1864   client = CLIENT_ID(((XMesaDrawable)p)->id);
1865#endif
1866
1867   assert(v);
1868
1869   b->xm_visual = v;
1870   b->type = PIXMAP;
1871   b->display = v->display;
1872   b->cmap = cmap;
1873
1874   /* determine back buffer implementation */
1875   if (v->mesa_visual.doubleBufferMode) {
1876      if (v->ximage_flag) {
1877	 b->db_state = BACK_XIMAGE;
1878      }
1879      else {
1880	 b->db_state = BACK_PIXMAP;
1881      }
1882   }
1883   else {
1884      b->db_state = 0;
1885   }
1886
1887   _mesa_initialize_framebuffer(&b->mesa_buffer,
1888                                &v->mesa_visual,
1889                                v->mesa_visual.depthBits > 0,
1890                                v->mesa_visual.stencilBits > 0,
1891                                v->mesa_visual.accumRedBits +
1892                                v->mesa_visual.accumGreenBits +
1893                                v->mesa_visual.accumBlueBits > 0,
1894                                v->mesa_visual.alphaBits > 0 );
1895
1896   if (!initialize_visual_and_buffer(client, v, b, v->mesa_visual.rgbMode,
1897				     (XMesaDrawable)p, cmap)) {
1898      free_xmesa_buffer(client, b);
1899      return NULL;
1900   }
1901
1902   return b;
1903}
1904
1905
1906
1907XMesaBuffer XMesaCreatePBuffer( XMesaVisual v, XMesaColormap cmap,
1908                                unsigned int width, unsigned int height )
1909{
1910#ifdef XFree86Server
1911   return 0;
1912#else
1913   int client = 0;
1914   XMesaWindow root;
1915   XMesaDrawable drawable;  /* X Pixmap Drawable */
1916   XMesaBuffer b = alloc_xmesa_buffer();
1917   if (!b) {
1918      return NULL;
1919   }
1920
1921   b->xm_visual = v;
1922   b->type = PBUFFER;
1923   b->display = v->display;
1924   b->cmap = cmap;
1925
1926   /* allocate pixmap for front buffer */
1927   root = RootWindow( v->display, v->visinfo->screen );
1928   drawable = XCreatePixmap( v->display, root, width, height, v->visinfo->depth );
1929
1930   /* determine back buffer implementation */
1931   if (v->mesa_visual.doubleBufferMode) {
1932      if (v->ximage_flag) {
1933	 b->db_state = BACK_XIMAGE;
1934      }
1935      else {
1936	 b->db_state = BACK_PIXMAP;
1937      }
1938   }
1939   else {
1940      b->db_state = 0;
1941   }
1942
1943   _mesa_initialize_framebuffer(&b->mesa_buffer,
1944                                &v->mesa_visual,
1945                                v->mesa_visual.depthBits > 0,
1946                                v->mesa_visual.stencilBits > 0,
1947                                v->mesa_visual.accumRedBits +
1948                                v->mesa_visual.accumGreenBits +
1949                                v->mesa_visual.accumBlueBits > 0,
1950                                v->mesa_visual.alphaBits > 0 );
1951
1952   if (!initialize_visual_and_buffer(client, v, b, v->mesa_visual.rgbMode,
1953				     drawable, cmap)) {
1954      free_xmesa_buffer(client, b);
1955      return NULL;
1956   }
1957
1958   return b;
1959#endif
1960}
1961
1962
1963
1964/*
1965 * Deallocate an XMesaBuffer structure and all related info.
1966 */
1967void XMesaDestroyBuffer( XMesaBuffer b )
1968{
1969   int client = 0;
1970
1971#ifdef XFree86Server
1972   if (b->frontbuffer)
1973       client = CLIENT_ID(b->frontbuffer->id);
1974#endif
1975
1976   if (b->gc)  XMesaFreeGC( b->xm_visual->display, b->gc );
1977   if (b->cleargc)  XMesaFreeGC( b->xm_visual->display, b->cleargc );
1978   if (b->swapgc)  XMesaFreeGC( b->xm_visual->display, b->swapgc );
1979
1980   if (b->backimage) {
1981#if defined(USE_XSHM) && !defined(XFree86Server)
1982       if (b->shm) {
1983	   XShmDetach( b->xm_visual->display, &b->shminfo );
1984	   XDestroyImage( b->backimage );
1985	   shmdt( b->shminfo.shmaddr );
1986       }
1987       else
1988#endif
1989	   XMesaDestroyImage( b->backimage );
1990   }
1991   if (b->backpixmap) {
1992      XMesaFreePixmap( b->xm_visual->display, b->backpixmap );
1993      if (b->xm_visual->hpcr_clear_flag) {
1994	XMesaFreePixmap( b->xm_visual->display,
1995			 b->xm_visual->hpcr_clear_pixmap );
1996	XMesaDestroyImage( b->xm_visual->hpcr_clear_ximage );
1997      }
1998   }
1999   if (b->rowimage) {
2000      FREE( b->rowimage->data );
2001      b->rowimage->data = NULL;
2002      XMesaDestroyImage( b->rowimage );
2003   }
2004
2005   free_xmesa_buffer(client, b);
2006}
2007
2008
2009
2010/*
2011 * Bind buffer b to context c and make c the current rendering context.
2012 */
2013GLboolean XMesaMakeCurrent( XMesaContext c, XMesaBuffer b )
2014{
2015   return XMesaMakeCurrent2( c, b, b );
2016}
2017
2018
2019/*
2020 * Bind buffer b to context c and make c the current rendering context.
2021 */
2022GLboolean XMesaMakeCurrent2( XMesaContext c, XMesaBuffer drawBuffer,
2023                             XMesaBuffer readBuffer )
2024{
2025   if (c) {
2026      if (!drawBuffer || !readBuffer)
2027         return GL_FALSE;  /* must specify buffers! */
2028
2029#ifdef FX
2030      if (drawBuffer->FXctx) {
2031         fxMesaMakeCurrent(drawBuffer->FXctx);
2032
2033         c->xm_draw_buffer = drawBuffer;
2034         c->xm_read_buffer = readBuffer;
2035         c->xm_buffer = drawBuffer;
2036
2037         return GL_TRUE;
2038      }
2039#endif
2040      if (&(c->mesa) == _mesa_get_current_context()
2041          && c->xm_draw_buffer == drawBuffer
2042          && c->xm_read_buffer == readBuffer
2043          && c->xm_draw_buffer->wasCurrent) {
2044         /* same context and buffer, do nothing */
2045         return GL_TRUE;
2046      }
2047
2048      c->xm_draw_buffer = drawBuffer;
2049      c->xm_read_buffer = readBuffer;
2050      c->xm_buffer = drawBuffer;
2051
2052      _mesa_make_current2(&(c->mesa),
2053                          &drawBuffer->mesa_buffer,
2054                          &readBuffer->mesa_buffer);
2055
2056      if (c->mesa.Viewport.Width == 0) {
2057	 /* initialize viewport to window size */
2058	 _mesa_Viewport( 0, 0, drawBuffer->width, drawBuffer->height );
2059	 c->mesa.Scissor.Width = drawBuffer->width;
2060	 c->mesa.Scissor.Height = drawBuffer->height;
2061      }
2062
2063      if (c->xm_visual->mesa_visual.rgbMode) {
2064         /*
2065          * Must recompute and set these pixel values because colormap
2066          * can be different for different windows.
2067          */
2068         c->clearpixel = xmesa_color_to_pixel( c,
2069                                               c->clearcolor[0],
2070                                               c->clearcolor[1],
2071                                               c->clearcolor[2],
2072                                               c->clearcolor[3],
2073                                               c->xm_visual->undithered_pf);
2074         XMesaSetForeground(c->display, c->xm_draw_buffer->cleargc, c->clearpixel);
2075      }
2076
2077      /* Solution to Stephane Rehel's problem with glXReleaseBuffersMESA(): */
2078      c->xm_draw_buffer->wasCurrent = GL_TRUE;
2079   }
2080   else {
2081      /* Detach */
2082      _mesa_make_current2( NULL, NULL, NULL );
2083   }
2084   return GL_TRUE;
2085}
2086
2087
2088/*
2089 * Unbind the context c from its buffer.
2090 */
2091GLboolean XMesaUnbindContext( XMesaContext c )
2092{
2093   /* A no-op for XFree86 integration purposes */
2094   return GL_TRUE;
2095}
2096
2097
2098XMesaContext XMesaGetCurrentContext( void )
2099{
2100   GET_CURRENT_CONTEXT(ctx);
2101   if (ctx) {
2102      XMesaContext xmesa = XMESA_CONTEXT(ctx);
2103      return xmesa;
2104   }
2105   else {
2106      return 0;
2107   }
2108}
2109
2110
2111XMesaBuffer XMesaGetCurrentBuffer( void )
2112{
2113   GET_CURRENT_CONTEXT(ctx);
2114   if (ctx) {
2115      XMesaContext xmesa = XMESA_CONTEXT(ctx);
2116      return xmesa->xm_draw_buffer;
2117   }
2118   else {
2119      return 0;
2120   }
2121}
2122
2123
2124/* New in Mesa 3.1 */
2125XMesaBuffer XMesaGetCurrentReadBuffer( void )
2126{
2127   GET_CURRENT_CONTEXT(ctx);
2128   if (ctx) {
2129      XMesaContext xmesa = XMESA_CONTEXT(ctx);
2130      return xmesa->xm_read_buffer;
2131   }
2132   else {
2133      return 0;
2134   }
2135}
2136
2137
2138GLboolean XMesaForceCurrent(XMesaContext c)
2139{
2140   if (c) {
2141      if (&(c->mesa) != _mesa_get_current_context()) {
2142	 _mesa_make_current(&(c->mesa), &c->xm_draw_buffer->mesa_buffer);
2143      }
2144   }
2145   else {
2146      _mesa_make_current(NULL, NULL);
2147   }
2148   return GL_TRUE;
2149}
2150
2151
2152GLboolean XMesaLoseCurrent(XMesaContext c)
2153{
2154   (void) c;
2155   _mesa_make_current(NULL, NULL);
2156   return GL_TRUE;
2157}
2158
2159
2160/*
2161 * Switch 3Dfx support hack between window and full-screen mode.
2162 */
2163GLboolean XMesaSetFXmode( GLint mode )
2164{
2165#ifdef FX
2166   const char *fx = _mesa_getenv("MESA_GLX_FX");
2167   if (fx && fx[0] != 'd') {
2168      GET_CURRENT_CONTEXT(ctx);
2169      GrHwConfiguration hw;
2170      if (!FX_grSstQueryHardware(&hw)) {
2171         /*fprintf(stderr, "!grSstQueryHardware\n");*/
2172         return GL_FALSE;
2173      }
2174      if (hw.num_sst < 1) {
2175         /*fprintf(stderr, "hw.num_sst < 1\n");*/
2176         return GL_FALSE;
2177      }
2178      if (ctx) {
2179         XMesaContext xmesa = XMESA_CONTEXT(ctx);
2180         if (mode == XMESA_FX_WINDOW) {
2181	    if (xmesa->xm_draw_buffer->FXisHackUsable) {
2182	       FX_grSstControl(GR_CONTROL_DEACTIVATE);
2183	       xmesa->xm_draw_buffer->FXwindowHack = GL_TRUE;
2184	       return GL_TRUE;
2185	    }
2186	 }
2187	 else if (mode == XMESA_FX_FULLSCREEN) {
2188	    FX_grSstControl(GR_CONTROL_ACTIVATE);
2189	    xmesa->xm_draw_buffer->FXwindowHack = GL_FALSE;
2190	    return GL_TRUE;
2191	 }
2192	 else {
2193	    /* Error: Bad mode value */
2194	 }
2195      }
2196   }
2197   /*fprintf(stderr, "fallthrough\n");*/
2198#else
2199   (void) mode;
2200#endif
2201   return GL_FALSE;
2202}
2203
2204
2205
2206#ifdef FX
2207/*
2208 * Read image from VooDoo frame buffer into X/Mesa's back XImage.
2209 */
2210static void FXgetImage( XMesaBuffer b )
2211{
2212   GET_CURRENT_CONTEXT(ctx);
2213   static unsigned short pixbuf[MAX_WIDTH];
2214   GLuint x, y;
2215   int xpos, ypos;
2216   XMesaWindow root;
2217   unsigned int bw, depth, width, height;
2218   XMesaContext xmesa = XMESA_CONTEXT(ctx);
2219
2220#ifdef XFree86Server
2221   x = b->frontbuffer->x;
2222   y = b->frontbuffer->y;
2223   width = b->frontbuffer->width;
2224   height = b->frontbuffer->height;
2225   depth = b->frontbuffer->depth;
2226#else
2227   XGetGeometry( b->xm_visual->display, b->frontbuffer,
2228                 &root, &xpos, &ypos, &width, &height, &bw, &depth);
2229#endif
2230   if (b->width != width || b->height != height) {
2231      b->width = MIN2((int)width, b->FXctx->width);
2232      b->height = MIN2((int)height, b->FXctx->height);
2233      if (b->width & 1)
2234         b->width--;  /* prevent odd width */
2235      xmesa_alloc_back_buffer( b );
2236   }
2237
2238   grLfbWriteColorFormat(GR_COLORFORMAT_ARGB);
2239   if (b->xm_visual->undithered_pf==PF_5R6G5B) {
2240      /* Special case: 16bpp RGB */
2241      grLfbReadRegion( GR_BUFFER_FRONTBUFFER,       /* src buffer */
2242                       0, b->FXctx->height - b->height,  /*pos*/
2243                       b->width, b->height,         /* size */
2244                       b->width * sizeof(GLushort), /* stride */
2245                       b->backimage->data);         /* dest buffer */
2246   }
2247   else if (b->xm_visual->dithered_pf==PF_Dither
2248	    && GET_VISUAL_DEPTH(b->xm_visual)==8) {
2249      /* Special case: 8bpp RGB */
2250      for (y=0;y<b->height;y++) {
2251         GLubyte *ptr = (GLubyte*) b->backimage->data
2252                        + b->backimage->bytes_per_line * y;
2253         XDITHER_SETUP(y);
2254
2255         /* read row from 3Dfx frame buffer */
2256         grLfbReadRegion( GR_BUFFER_FRONTBUFFER,
2257                          0, b->FXctx->height-(b->height-y),
2258                          b->width, 1,
2259                          0,
2260                          pixbuf );
2261
2262         /* write to XImage back buffer */
2263         for (x=0;x<b->width;x++) {
2264            GLubyte r = (pixbuf[x] & 0xf800) >> 8;
2265            GLubyte g = (pixbuf[x] & 0x07e0) >> 3;
2266            GLubyte b = (pixbuf[x] & 0x001f) << 3;
2267            *ptr++ = XDITHER( x, r, g, b);
2268         }
2269      }
2270   }
2271   else {
2272      /* General case: slow! */
2273      for (y=0;y<b->height;y++) {
2274         /* read row from 3Dfx frame buffer */
2275         grLfbReadRegion( GR_BUFFER_FRONTBUFFER,
2276                          0, b->FXctx->height-(b->height-y),
2277                          b->width, 1,
2278                          0,
2279                          pixbuf );
2280
2281         /* write to XImage back buffer */
2282         for (x=0;x<b->width;x++) {
2283            XMesaPutPixel(b->backimage,x,y,
2284			  xmesa_color_to_pixel(xmesa,
2285					       (pixbuf[x] & 0xf800) >> 8,
2286					       (pixbuf[x] & 0x07e0) >> 3,
2287					       (pixbuf[x] & 0x001f) << 3,
2288					       0xff,
2289                                               b->xm_visual->undithered_pf));
2290         }
2291      }
2292   }
2293   grLfbWriteColorFormat(GR_COLORFORMAT_ABGR);
2294}
2295#endif
2296
2297
2298/*
2299 * Copy the back buffer to the front buffer.  If there's no back buffer
2300 * this is a no-op.
2301 */
2302void XMesaSwapBuffers( XMesaBuffer b )
2303{
2304   GET_CURRENT_CONTEXT(ctx);
2305
2306   /* If we're swapping the buffer associated with the current context
2307    * we have to flush any pending rendering commands first.
2308    */
2309   if (ctx && ctx->DrawBuffer == &(b->mesa_buffer))
2310      _mesa_notifySwapBuffers(ctx);
2311
2312   if (b->db_state) {
2313#ifdef FX
2314      if (b->FXctx) {
2315         fxMesaSwapBuffers();
2316
2317         if (b->FXwindowHack)
2318            FXgetImage(b);
2319         else
2320            return;
2321      }
2322#endif
2323     if (b->backimage) {
2324	 /* Copy Ximage from host's memory to server's window */
2325#if defined(USE_XSHM) && !defined(XFree86Server)
2326	 if (b->shm) {
2327            /*_glthread_LOCK_MUTEX(_xmesa_lock);*/
2328	    XShmPutImage( b->xm_visual->display, b->frontbuffer,
2329			  b->swapgc,
2330			  b->backimage, 0, 0,
2331			  0, 0, b->width, b->height, False );
2332            /*_glthread_UNLOCK_MUTEX(_xmesa_lock);*/
2333	 }
2334	 else
2335#endif
2336         {
2337            /*_glthread_LOCK_MUTEX(_xmesa_lock);*/
2338            XMesaPutImage( b->xm_visual->display, b->frontbuffer,
2339			   b->swapgc,
2340			   b->backimage, 0, 0,
2341			   0, 0, b->width, b->height );
2342            /*_glthread_UNLOCK_MUTEX(_xmesa_lock);*/
2343         }
2344      }
2345      else {
2346	 /* Copy pixmap to window on server */
2347         /*_glthread_LOCK_MUTEX(_xmesa_lock);*/
2348	 XMesaCopyArea( b->xm_visual->display,
2349			b->backpixmap,   /* source drawable */
2350			b->frontbuffer,  /* dest. drawable */
2351			b->swapgc,
2352			0, 0, b->width, b->height,  /* source region */
2353			0, 0                 /* dest region */
2354		      );
2355         /*_glthread_UNLOCK_MUTEX(_xmesa_lock);*/
2356      }
2357   }
2358#if !defined(XFree86Server)
2359   XSync( b->xm_visual->display, False );
2360#endif
2361}
2362
2363
2364
2365/*
2366 * Copy sub-region of back buffer to front buffer
2367 */
2368void XMesaCopySubBuffer( XMesaBuffer b, int x, int y, int width, int height )
2369{
2370   GET_CURRENT_CONTEXT(ctx);
2371
2372   /* If we're swapping the buffer associated with the current context
2373    * we have to flush any pending rendering commands first.
2374    */
2375   if (ctx && ctx->DrawBuffer == &(b->mesa_buffer))
2376      _mesa_notifySwapBuffers(ctx);
2377
2378   if (b->db_state) {
2379      int yTop = b->height - y - height;
2380#ifdef FX
2381      if (b->FXctx) {
2382         fxMesaSwapBuffers();
2383         if (b->FXwindowHack)
2384            FXgetImage(b);
2385         else
2386            return;
2387      }
2388#endif
2389      if (b->backimage) {
2390         /* Copy Ximage from host's memory to server's window */
2391#if defined(USE_XSHM) && !defined(XFree86Server)
2392         if (b->shm) {
2393            /* XXX assuming width and height aren't too large! */
2394            XShmPutImage( b->xm_visual->display, b->frontbuffer,
2395                          b->swapgc,
2396                          b->backimage, x, yTop,
2397                          x, yTop, width, height, False );
2398            /* wait for finished event??? */
2399         }
2400         else
2401#endif
2402         {
2403            /* XXX assuming width and height aren't too large! */
2404            XMesaPutImage( b->xm_visual->display, b->frontbuffer,
2405			   b->swapgc,
2406			   b->backimage, x, yTop,
2407			   x, yTop, width, height );
2408         }
2409      }
2410      else {
2411         /* Copy pixmap to window on server */
2412         XMesaCopyArea( b->xm_visual->display,
2413			b->backpixmap,           /* source drawable */
2414			b->frontbuffer,          /* dest. drawable */
2415			b->swapgc,
2416			x, yTop, width, height,  /* source region */
2417			x, yTop                  /* dest region */
2418                      );
2419      }
2420   }
2421}
2422
2423
2424/*
2425 * Return a pointer to the XMesa backbuffer Pixmap or XImage.  This function
2426 * is a way to get "under the hood" of X/Mesa so one can manipulate the
2427 * back buffer directly.
2428 * Output:  pixmap - pointer to back buffer's Pixmap, or 0
2429 *          ximage - pointer to back buffer's XImage, or NULL
2430 * Return:  GL_TRUE = context is double buffered
2431 *          GL_FALSE = context is single buffered
2432 */
2433GLboolean XMesaGetBackBuffer( XMesaBuffer b,
2434                              XMesaPixmap *pixmap,
2435                              XMesaImage **ximage )
2436{
2437   if (b->db_state) {
2438      if (pixmap)  *pixmap = b->backpixmap;
2439      if (ximage)  *ximage = b->backimage;
2440      return GL_TRUE;
2441   }
2442   else {
2443      *pixmap = 0;
2444      *ximage = NULL;
2445      return GL_FALSE;
2446   }
2447}
2448
2449
2450/*
2451 * Return the depth buffer associated with an XMesaBuffer.
2452 * Input:  b - the XMesa buffer handle
2453 * Output:  width, height - size of buffer in pixels
2454 *          bytesPerValue - bytes per depth value (2 or 4)
2455 *          buffer - pointer to depth buffer values
2456 * Return:  GL_TRUE or GL_FALSE to indicate success or failure.
2457 */
2458GLboolean XMesaGetDepthBuffer( XMesaBuffer b, GLint *width, GLint *height,
2459                               GLint *bytesPerValue, void **buffer )
2460{
2461   if (!b->mesa_buffer.DepthBuffer) {
2462      *width = 0;
2463      *height = 0;
2464      *bytesPerValue = 0;
2465      *buffer = 0;
2466      return GL_FALSE;
2467   }
2468   else {
2469      *width = b->mesa_buffer.Width;
2470      *height = b->mesa_buffer.Height;
2471      *bytesPerValue = sizeof(GLdepth);
2472      *buffer = b->mesa_buffer.DepthBuffer;
2473      return GL_TRUE;
2474   }
2475}
2476
2477
2478void XMesaFlush( XMesaContext c )
2479{
2480   if (c && c->xm_visual) {
2481#ifdef XFree86Server
2482      /* NOT_NEEDED */
2483#else
2484      XSync( c->xm_visual->display, False );
2485#endif
2486   }
2487}
2488
2489
2490
2491const char *XMesaGetString( XMesaContext c, int name )
2492{
2493   (void) c;
2494   if (name==XMESA_VERSION) {
2495      return "5.0";
2496   }
2497   else if (name==XMESA_EXTENSIONS) {
2498      return "";
2499   }
2500   else {
2501      return NULL;
2502   }
2503}
2504
2505
2506
2507XMesaBuffer XMesaFindBuffer( XMesaDisplay *dpy, XMesaDrawable d )
2508{
2509   XMesaBuffer b;
2510   for (b=XMesaBufferList; b; b=b->Next) {
2511      if (b->frontbuffer==d && b->display==dpy) {
2512         return b;
2513      }
2514   }
2515   return NULL;
2516}
2517
2518
2519
2520/*
2521 * Look for XMesaBuffers whose X window has been destroyed.
2522 * Deallocate any such XMesaBuffers.
2523 */
2524void XMesaGarbageCollect( void )
2525{
2526   XMesaBuffer b, next;
2527   for (b=XMesaBufferList; b; b=next) {
2528      next = b->Next;
2529      if (b->display && b->frontbuffer && b->type == WINDOW) {
2530#ifdef XFree86Server
2531	 /* NOT_NEEDED */
2532#else
2533         XSync(b->display, False);
2534         if (!window_exists( b->display, b->frontbuffer )) {
2535            /* found a dead window, free the ancillary info */
2536            XMesaDestroyBuffer( b );
2537         }
2538#endif
2539      }
2540   }
2541}
2542
2543
2544void XMesaReset( void )
2545{
2546    while (XMesaBufferList)
2547	XMesaDestroyBuffer(XMesaBufferList);
2548
2549    XMesaBufferList = NULL;
2550}
2551
2552
2553unsigned long XMesaDitherColor( XMesaContext xmesa, GLint x, GLint y,
2554                                GLfloat red, GLfloat green,
2555                                GLfloat blue, GLfloat alpha )
2556{
2557   GLint r = (GLint) (red   * 255.0F);
2558   GLint g = (GLint) (green * 255.0F);
2559   GLint b = (GLint) (blue  * 255.0F);
2560   GLint a = (GLint) (alpha * 255.0F);
2561
2562   switch (xmesa->pixelformat) {
2563      case PF_Index:
2564         return 0;
2565      case PF_Truecolor:
2566         {
2567            unsigned long p;
2568            PACK_TRUECOLOR( p, r, g, b );
2569            return p;
2570         }
2571      case PF_8A8B8G8R:
2572         return PACK_8A8B8G8R( r, g, b, a );
2573      case PF_8R8G8B:
2574         return PACK_8R8G8B( r, g, b );
2575      case PF_5R6G5B:
2576         return PACK_5R6G5B( r, g, b );
2577      case PF_Dither:
2578         {
2579            DITHER_SETUP;
2580            return DITHER( x, y, r, g, b );
2581         }
2582      case PF_1Bit:
2583         /* 382 = (3*255)/2 */
2584         return ((r+g+b) > 382) ^ xmesa->xm_visual->bitFlip;
2585      case PF_HPCR:
2586         return DITHER_HPCR(x, y, r, g, b);
2587      case PF_Lookup:
2588         {
2589            LOOKUP_SETUP;
2590            return LOOKUP( r, g, b );
2591         }
2592      case PF_Grayscale:
2593         return GRAY_RGB( r, g, b );
2594      case PF_Dither_5R6G5B:
2595         /* fall through */
2596      case PF_Dither_True:
2597         {
2598            unsigned long p;
2599            PACK_TRUEDITHER(p, x, y, r, g, b);
2600            return p;
2601         }
2602      default:
2603         _mesa_problem(NULL, "Bad pixel format in XMesaDitherColor");
2604   }
2605   return 0;
2606}
2607
2608
2609/*
2610 * This is typically called when the window size changes and we need
2611 * to reallocate the buffer's back/depth/stencil/accum buffers.
2612 */
2613void XMesaResizeBuffers( XMesaBuffer b )
2614{
2615   xmesa_resize_buffers( &(b->mesa_buffer) );
2616
2617}
2618
2619