xm_api.c revision 894844a8d956a0ee5f95836331dc318f49fdb845 
1/*
2 * Mesa 3-D graphics library
3 * Version:  6.1
4 *
5 * Copyright (C) 1999-2004  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
25/*
26 * This file contains the implementations of all the XMesa* functions.
27 *
28 *
29 * NOTES:
30 *
31 * The window coordinate system origin (0,0) is in the lower-left corner
32 * of the window.  X11's window coordinate origin is in the upper-left
33 * corner of the window.  Therefore, most drawing functions in this
34 * file have to flip Y coordinates.
35 *
36 * Define USE_XSHM in the Makefile with -DUSE_XSHM if you want to compile
37 * in support for the MIT Shared Memory extension.  If enabled, when you
38 * use an Ximage for the back buffer in double buffered mode, the "swap"
39 * operation will be faster.  You must also link with -lXext.
40 *
41 * Byte swapping:  If the Mesa host and the X display use a different
42 * byte order then there's some trickiness to be aware of when using
43 * XImages.  The byte ordering used for the XImage is that of the X
44 * display, not the Mesa host.
45 * The color-to-pixel encoding for True/DirectColor must be done
46 * according to the display's visual red_mask, green_mask, and blue_mask.
47 * If XPutPixel is used to put a pixel into an XImage then XPutPixel will
48 * do byte swapping if needed.  If one wants to directly "poke" the pixel
49 * into the XImage's buffer then the pixel must be byte swapped first.  In
50 * Mesa, when byte swapping is needed we use the PF_TRUECOLOR pixel format
51 * and use XPutPixel everywhere except in the implementation of
52 * glClear(GL_COLOR_BUFFER_BIT).  We want this function to be fast so
53 * instead of using XPutPixel we "poke" our values after byte-swapping
54 * the clear pixel value if needed.
55 *
56 */
57
58#ifdef __CYGWIN__
59#undef WIN32
60#undef __WIN32__
61#endif
62
63#include "glxheader.h"
64#include "GL/xmesa.h"
65#include "xmesaP.h"
66#include "context.h"
67#include "extensions.h"
68#include "glthread.h"
69#include "imports.h"
70#include "matrix.h"
71#include "mtypes.h"
72#include "macros.h"
73#include "texformat.h"
74#include "texobj.h"
75#include "texstore.h"
76#include "swrast/swrast.h"
77#include "swrast_setup/swrast_setup.h"
78#include "array_cache/acache.h"
79#include "tnl/tnl.h"
80#include "tnl/t_context.h"
81#include "tnl/t_pipeline.h"
82#include "drivers/common/driverfuncs.h"
83
84#ifdef XFree86Server
85#include <GL/glxtokens.h>
86#endif
87
88/*
89 * Global X driver lock
90 */
91_glthread_Mutex _xmesa_lock;
92
93
94
95/*
96 * Lookup tables for HPCR pixel format:
97 */
98static short hpcr_rgbTbl[3][256] = {
99{
100 16,  16,  17,  17,  18,  18,  19,  19,  20,  20,  21,  21,  22,  22,  23,  23,
101 24,  24,  25,  25,  26,  26,  27,  27,  28,  28,  29,  29,  30,  30,  31,  31,
102 32,  32,  33,  33,  34,  34,  35,  35,  36,  36,  37,  37,  38,  38,  39,  39,
103 32,  33,  34,  35,  36,  37,  38,  39,  40,  41,  42,  43,  44,  45,  46,  47,
104 48,  49,  50,  51,  52,  53,  54,  55,  56,  57,  58,  59,  60,  61,  62,  63,
105 64,  65,  66,  67,  68,  69,  70,  71,  72,  73,  74,  75,  76,  77,  78,  79,
106 80,  81,  82,  83,  84,  85,  86,  87,  88,  89,  90,  91,  92,  93,  94,  95,
107 96,  97,  98,  99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111,
108112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127,
109128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143,
110144, 145, 146, 147, 148, 149, 150, 151, 152, 153, 154, 155, 156, 157, 158, 159,
111160, 161, 162, 163, 164, 165, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175,
112176, 177, 178, 179, 180, 181, 182, 183, 184, 185, 186, 187, 188, 189, 190, 191,
113192, 193, 194, 195, 196, 197, 198, 199, 200, 201, 202, 203, 204, 205, 206, 207,
114208, 209, 210, 211, 212, 213, 214, 215, 216, 217, 218, 219, 220, 221, 222, 223,
115224, 225, 226, 227, 228, 229, 230, 231, 232, 233, 234, 235, 236, 237, 238, 239
116},
117{
118 16,  16,  17,  17,  18,  18,  19,  19,  20,  20,  21,  21,  22,  22,  23,  23,
119 24,  24,  25,  25,  26,  26,  27,  27,  28,  28,  29,  29,  30,  30,  31,  31,
120 32,  32,  33,  33,  34,  34,  35,  35,  36,  36,  37,  37,  38,  38,  39,  39,
121 32,  33,  34,  35,  36,  37,  38,  39,  40,  41,  42,  43,  44,  45,  46,  47,
122 48,  49,  50,  51,  52,  53,  54,  55,  56,  57,  58,  59,  60,  61,  62,  63,
123 64,  65,  66,  67,  68,  69,  70,  71,  72,  73,  74,  75,  76,  77,  78,  79,
124 80,  81,  82,  83,  84,  85,  86,  87,  88,  89,  90,  91,  92,  93,  94,  95,
125 96,  97,  98,  99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111,
126112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127,
127128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143,
128144, 145, 146, 147, 148, 149, 150, 151, 152, 153, 154, 155, 156, 157, 158, 159,
129160, 161, 162, 163, 164, 165, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175,
130176, 177, 178, 179, 180, 181, 182, 183, 184, 185, 186, 187, 188, 189, 190, 191,
131192, 193, 194, 195, 196, 197, 198, 199, 200, 201, 202, 203, 204, 205, 206, 207,
132208, 209, 210, 211, 212, 213, 214, 215, 216, 217, 218, 219, 220, 221, 222, 223,
133224, 225, 226, 227, 228, 229, 230, 231, 232, 233, 234, 235, 236, 237, 238, 239
134},
135{
136 32,  32,  33,  33,  34,  34,  35,  35,  36,  36,  37,  37,  38,  38,  39,  39,
137 40,  40,  41,  41,  42,  42,  43,  43,  44,  44,  45,  45,  46,  46,  47,  47,
138 48,  48,  49,  49,  50,  50,  51,  51,  52,  52,  53,  53,  54,  54,  55,  55,
139 56,  56,  57,  57,  58,  58,  59,  59,  60,  60,  61,  61,  62,  62,  63,  63,
140 64,  64,  65,  65,  66,  66,  67,  67,  68,  68,  69,  69,  70,  70,  71,  71,
141 72,  72,  73,  73,  74,  74,  75,  75,  76,  76,  77,  77,  78,  78,  79,  79,
142 80,  80,  81,  81,  82,  82,  83,  83,  84,  84,  85,  85,  86,  86,  87,  87,
143 80,  81,  82,  83,  84,  85,  86,  87,  88,  89,  90,  91,  92,  93,  94,  95,
144 96,  97,  98,  99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111,
145112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127,
146128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143,
147144, 145, 146, 147, 148, 149, 150, 151, 152, 153, 154, 155, 156, 157, 158, 159,
148160, 161, 162, 163, 164, 165, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175,
149176, 177, 178, 179, 180, 181, 182, 183, 184, 185, 186, 187, 188, 189, 190, 191,
150192, 193, 194, 195, 196, 197, 198, 199, 200, 201, 202, 203, 204, 205, 206, 207,
151208, 209, 210, 211, 212, 213, 214, 215, 216, 217, 218, 219, 220, 221, 222, 223
152}
153};
154
155
156
157/**********************************************************************/
158/*****                     X Utility Functions                    *****/
159/**********************************************************************/
160
161
162/*
163 * Return the host's byte order as LSBFirst or MSBFirst ala X.
164 */
165#ifndef XFree86Server
166static int host_byte_order( void )
167{
168   int i = 1;
169   char *cptr = (char *) &i;
170   return (*cptr==1) ? LSBFirst : MSBFirst;
171}
172#endif
173
174
175/*
176 * Error handling.
177 */
178#ifndef XFree86Server
179static volatile int mesaXErrorFlag = 0;
180
181static int mesaHandleXError( XMesaDisplay *dpy, XErrorEvent *event )
182{
183   (void) dpy;
184   (void) event;
185   mesaXErrorFlag = 1;
186   return 0;
187}
188#endif
189
190
191/*
192 * Check if the X Shared Memory extension is available.
193 * Return:  0 = not available
194 *          1 = shared XImage support available
195 *          2 = shared Pixmap support available also
196 */
197#ifndef XFree86Server
198static int check_for_xshm( XMesaDisplay *display )
199{
200#ifdef USE_XSHM
201   int major, minor, ignore;
202   Bool pixmaps;
203
204   if (XQueryExtension( display, "MIT-SHM", &ignore, &ignore, &ignore )) {
205      if (XShmQueryVersion( display, &major, &minor, &pixmaps )==True) {
206	 return (pixmaps==True) ? 2 : 1;
207      }
208      else {
209	 return 0;
210      }
211   }
212   else {
213      return 0;
214   }
215#else
216   /* Can't compile XSHM support */
217   return 0;
218#endif
219}
220#endif
221
222
223/*
224 * Return the width and height of the given drawable.
225 */
226static void get_drawable_size( XMesaDisplay *dpy, XMesaDrawable d,
227                               unsigned int *width, unsigned int *height)
228{
229#ifdef XFree86Server
230    (void) dpy;
231    *width = d->width;
232    *height = d->height;
233#else
234   Window root;
235   int x, y;
236   unsigned int bw, depth;
237
238   _glthread_LOCK_MUTEX(_xmesa_lock);
239   XGetGeometry( dpy, d, &root, &x, &y, width, height, &bw, &depth );
240   _glthread_UNLOCK_MUTEX(_xmesa_lock);
241#endif
242}
243
244
245/*
246 * Apply gamma correction to an intensity value in [0..max].  Return the
247 * new intensity value.
248 */
249static GLint gamma_adjust( GLfloat gamma, GLint value, GLint max )
250{
251   if (gamma == 1.0) {
252      return value;
253   }
254   else {
255      double x = (double) value / (double) max;
256      return IROUND_POS((GLfloat) max * _mesa_pow(x, 1.0F/gamma));
257   }
258}
259
260
261
262/*
263 * Return the true number of bits per pixel for XImages.
264 * For example, if we request a 24-bit deep visual we may actually need/get
265 * 32bpp XImages.  This function returns the appropriate bpp.
266 * Input:  dpy - the X display
267 *         visinfo - desribes the visual to be used for XImages
268 * Return:  true number of bits per pixel for XImages
269 */
270#ifdef XFree86Server
271
272static int bits_per_pixel( XMesaVisual xmv )
273{
274   const int depth = xmv->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->mesa_visual.indexBits = GET_VISUAL_DEPTH(v);
1199   }
1200   else {
1201      /* RGB WINDOW:
1202       * We support RGB rendering into almost any kind of visual.
1203       */
1204      const int xclass = v->mesa_visual.visualType;
1205      if (xclass==GLX_TRUE_COLOR || xclass==GLX_DIRECT_COLOR) {
1206	 setup_truecolor( v, b, cmap );
1207      }
1208      else if (xclass==GLX_STATIC_GRAY && GET_VISUAL_DEPTH(v)==1) {
1209	 setup_monochrome( v, b );
1210      }
1211      else if (xclass==GLX_GRAY_SCALE || xclass==GLX_STATIC_GRAY) {
1212         if (!setup_grayscale( client, v, b, cmap )) {
1213            return GL_FALSE;
1214         }
1215      }
1216      else if ((xclass==GLX_PSEUDO_COLOR || xclass==GLX_STATIC_COLOR)
1217               && GET_VISUAL_DEPTH(v)>=4 && GET_VISUAL_DEPTH(v)<=16) {
1218	 if (!setup_dithered_color( client, v, b, cmap )) {
1219            return GL_FALSE;
1220         }
1221      }
1222      else {
1223	 _mesa_warning(NULL, "XMesa: RGB mode rendering not supported in given visual.");
1224	 return GL_FALSE;
1225      }
1226      v->mesa_visual.indexBits = 0;
1227
1228      if (_mesa_getenv("MESA_NO_DITHER")) {
1229	 v->dithered_pf = v->undithered_pf;
1230      }
1231   }
1232
1233
1234   /*
1235    * If MESA_INFO env var is set print out some debugging info
1236    * which can help Brian figure out what's going on when a user
1237    * reports bugs.
1238    */
1239   if (_mesa_getenv("MESA_INFO")) {
1240      _mesa_printf("X/Mesa visual = %p\n", (void *) v);
1241      _mesa_printf("X/Mesa dithered pf = %u\n", v->dithered_pf);
1242      _mesa_printf("X/Mesa undithered pf = %u\n", v->undithered_pf);
1243      _mesa_printf("X/Mesa level = %d\n", v->mesa_visual.level);
1244      _mesa_printf("X/Mesa depth = %d\n", GET_VISUAL_DEPTH(v));
1245      _mesa_printf("X/Mesa bits per pixel = %d\n", v->BitsPerPixel);
1246   }
1247
1248   if (b && window) {
1249      /* Do window-specific initializations */
1250
1251      /* Window dimensions */
1252      unsigned int w, h;
1253      get_drawable_size( v->display, window, &w, &h );
1254      b->width = w;
1255      b->height = h;
1256
1257      b->frontbuffer = window;
1258
1259      /* Setup for single/double buffering */
1260      if (v->mesa_visual.doubleBufferMode) {
1261         /* Double buffered */
1262#ifndef XFree86Server
1263         b->shm = check_for_xshm( v->display );
1264#endif
1265         xmesa_alloc_back_buffer( b );
1266         if (b->db_state==BACK_PIXMAP) {
1267            b->buffer = (XMesaDrawable)b->backpixmap;
1268         }
1269         else {
1270            b->buffer = XIMAGE;
1271         }
1272      }
1273      else {
1274         /* Single Buffered */
1275         b->buffer = b->frontbuffer;
1276      }
1277
1278      /* X11 graphics contexts */
1279#ifdef XFree86Server
1280      b->gc = CreateScratchGC(v->display, window->depth);
1281#else
1282      b->gc = XCreateGC( v->display, window, 0, NULL );
1283#endif
1284      XMesaSetFunction( v->display, b->gc, GXcopy );
1285
1286      /* cleargc - for glClear() */
1287#ifdef XFree86Server
1288      b->cleargc = CreateScratchGC(v->display, window->depth);
1289#else
1290      b->cleargc = XCreateGC( v->display, window, 0, NULL );
1291#endif
1292      XMesaSetFunction( v->display, b->cleargc, GXcopy );
1293
1294      /*
1295       * Don't generate Graphics Expose/NoExpose events in swapbuffers().
1296       * Patch contributed by Michael Pichler May 15, 1995.
1297       */
1298#ifdef XFree86Server
1299      b->swapgc = CreateScratchGC(v->display, window->depth);
1300      {
1301	  CARD32 v[1];
1302	  v[0] = FALSE;
1303	  dixChangeGC(NullClient, b->swapgc, GCGraphicsExposures, v, NULL);
1304      }
1305#else
1306      gcvalues.graphics_exposures = False;
1307      b->swapgc = XCreateGC( v->display, window,
1308                              GCGraphicsExposures, &gcvalues);
1309#endif
1310      XMesaSetFunction( v->display, b->swapgc, GXcopy );
1311      /*
1312       * Set fill style and tile pixmap once for all for HPCR stuff
1313       * (instead of doing it each time in clear_color_HPCR_pixmap())
1314       * Initialize whole stuff
1315       * Patch contributed by Jacques Leroy March 8, 1998.
1316       */
1317      if (v->hpcr_clear_flag && b->buffer!=XIMAGE) {
1318	int i;
1319	for (i=0; i<16; i++)
1320        {
1321	   XMesaPutPixel(v->hpcr_clear_ximage, i, 0, 0);
1322	   XMesaPutPixel(v->hpcr_clear_ximage, i, 1, 0);
1323        }
1324        XMesaPutImage(b->display, (XMesaDrawable)v->hpcr_clear_pixmap,
1325		      b->cleargc, v->hpcr_clear_ximage, 0, 0, 0, 0, 16, 2);
1326	XMesaSetFillStyle( v->display, b->cleargc, FillTiled);
1327	XMesaSetTile( v->display, b->cleargc, v->hpcr_clear_pixmap );
1328      }
1329
1330      /* Initialize the row buffer XImage for use in write_color_span() */
1331#ifdef XFree86Server
1332      b->rowimage = XMesaCreateImage(GET_VISUAL_DEPTH(v), MAX_WIDTH, 1,
1333				     (char *)MALLOC(MAX_WIDTH*4));
1334#else
1335      b->rowimage = XCreateImage( v->display,
1336                                  v->visinfo->visual,
1337                                  v->visinfo->depth,
1338                                  ZPixmap, 0,           /*format, offset*/
1339                                  (char*) MALLOC(MAX_WIDTH*4),  /*data*/
1340                                  MAX_WIDTH, 1,         /*width, height*/
1341                                  32,                   /*bitmap_pad*/
1342                                  0                     /*bytes_per_line*/ );
1343#endif
1344   }
1345
1346   return GL_TRUE;
1347}
1348
1349
1350
1351/*
1352 * Convert an RGBA color to a pixel value.
1353 */
1354unsigned long
1355xmesa_color_to_pixel( XMesaContext xmesa, GLubyte r, GLubyte g, GLubyte b, GLubyte a,
1356                      GLuint pixelFormat)
1357{
1358   switch (pixelFormat) {
1359      case PF_Index:
1360         return 0;
1361      case PF_Truecolor:
1362         {
1363            unsigned long p;
1364            PACK_TRUECOLOR( p, r, g, b );
1365            return p;
1366         }
1367      case PF_8A8B8G8R:
1368         return PACK_8A8B8G8R( r, g, b, a );
1369      case PF_8R8G8B:
1370         /* fall through */
1371      case PF_8R8G8B24:
1372         return PACK_8R8G8B( r, g, b );
1373      case PF_5R6G5B:
1374         return PACK_5R6G5B( r, g, b );
1375      case PF_Dither:
1376         {
1377            DITHER_SETUP;
1378            return DITHER( 1, 0, r, g, b );
1379         }
1380      case PF_1Bit:
1381         /* 382 = (3*255)/2 */
1382         return ((r+g+b) > 382) ^ xmesa->xm_visual->bitFlip;
1383      case PF_HPCR:
1384         return DITHER_HPCR(1, 1, r, g, b);
1385      case PF_Lookup:
1386         {
1387            LOOKUP_SETUP;
1388            return LOOKUP( r, g, b );
1389         }
1390      case PF_Grayscale:
1391         return GRAY_RGB( r, g, b );
1392      case PF_Dither_True:
1393         /* fall through */
1394      case PF_Dither_5R6G5B:
1395         {
1396            unsigned long p;
1397            PACK_TRUEDITHER(p, 1, 0, r, g, b);
1398            return p;
1399         }
1400      default:
1401         _mesa_problem(NULL, "Bad pixel format in xmesa_color_to_pixel");
1402   }
1403   return 0;
1404}
1405
1406
1407#define NUM_VISUAL_TYPES   6
1408
1409/**
1410 * Convert an X visual type to a GLX visual type.
1411 *
1412 * \param visualType X visual type (i.e., \c TrueColor, \c StaticGray, etc.)
1413 *        to be converted.
1414 * \return If \c visualType is a valid X visual type, a GLX visual type will
1415 *         be returned.  Otherwise \c GLX_NONE will be returned.
1416 *
1417 * \note
1418 * This code was lifted directly from lib/GL/glx/glcontextmodes.c in the
1419 * DRI CVS tree.
1420 */
1421static GLint
1422xmesa_convert_from_x_visual_type( int visualType )
1423{
1424    static const int glx_visual_types[ NUM_VISUAL_TYPES ] = {
1425	GLX_STATIC_GRAY,  GLX_GRAY_SCALE,
1426	GLX_STATIC_COLOR, GLX_PSEUDO_COLOR,
1427	GLX_TRUE_COLOR,   GLX_DIRECT_COLOR
1428    };
1429
1430    return ( (unsigned) visualType < NUM_VISUAL_TYPES )
1431	? glx_visual_types[ visualType ] : GLX_NONE;
1432}
1433
1434
1435/**********************************************************************/
1436/*****                       Public Functions                     *****/
1437/**********************************************************************/
1438
1439
1440/*
1441 * Create a new X/Mesa visual.
1442 * Input:  display - X11 display
1443 *         visinfo - an XVisualInfo pointer
1444 *         rgb_flag - GL_TRUE = RGB mode,
1445 *                    GL_FALSE = color index mode
1446 *         alpha_flag - alpha buffer requested?
1447 *         db_flag - GL_TRUE = double-buffered,
1448 *                   GL_FALSE = single buffered
1449 *         stereo_flag - stereo visual?
1450 *         ximage_flag - GL_TRUE = use an XImage for back buffer,
1451 *                       GL_FALSE = use an off-screen pixmap for back buffer
1452 *         depth_size - requested bits/depth values, or zero
1453 *         stencil_size - requested bits/stencil values, or zero
1454 *         accum_red_size - requested bits/red accum values, or zero
1455 *         accum_green_size - requested bits/green accum values, or zero
1456 *         accum_blue_size - requested bits/blue accum values, or zero
1457 *         accum_alpha_size - requested bits/alpha accum values, or zero
1458 *         num_samples - number of samples/pixel if multisampling, or zero
1459 *         level - visual level, usually 0
1460 *         visualCaveat - ala the GLX extension, usually GLX_NONE
1461 * Return;  a new XMesaVisual or 0 if error.
1462 */
1463XMesaVisual XMesaCreateVisual( XMesaDisplay *display,
1464                               XMesaVisualInfo visinfo,
1465                               GLboolean rgb_flag,
1466                               GLboolean alpha_flag,
1467                               GLboolean db_flag,
1468                               GLboolean stereo_flag,
1469                               GLboolean ximage_flag,
1470                               GLint depth_size,
1471                               GLint stencil_size,
1472                               GLint accum_red_size,
1473                               GLint accum_green_size,
1474                               GLint accum_blue_size,
1475                               GLint accum_alpha_size,
1476                               GLint num_samples,
1477                               GLint level,
1478                               GLint visualCaveat )
1479{
1480   char *gamma;
1481   XMesaVisual v;
1482   GLint red_bits, green_bits, blue_bits, alpha_bits;
1483
1484   /* For debugging only */
1485   if (_mesa_getenv("MESA_XSYNC")) {
1486      /* This makes debugging X easier.
1487       * In your debugger, set a breakpoint on _XError to stop when an
1488       * X protocol error is generated.
1489       */
1490#ifdef XFree86Server
1491      /* NOT_NEEDED */
1492#else
1493      XSynchronize( display, 1 );
1494#endif
1495   }
1496
1497   v = (XMesaVisual) CALLOC_STRUCT(xmesa_visual);
1498   if (!v) {
1499      return NULL;
1500   }
1501
1502   /*
1503    * In the X server, NULL is passed in for the display.  It will have
1504    * to be set before using this visual.  See XMesaSetVisualDisplay()
1505    * below.
1506    */
1507   v->display = display;
1508
1509   /* Save a copy of the XVisualInfo struct because the user may XFREE()
1510    * the struct but we may need some of the information contained in it
1511    * at a later time.
1512    */
1513#ifndef XFree86Server
1514   v->visinfo = (XVisualInfo *) MALLOC(sizeof(*visinfo));
1515   if(!v->visinfo) {
1516      FREE(v);
1517      return NULL;
1518   }
1519   MEMCPY(v->visinfo, visinfo, sizeof(*visinfo));
1520#endif
1521
1522   /* check for MESA_GAMMA environment variable */
1523   gamma = _mesa_getenv("MESA_GAMMA");
1524   if (gamma) {
1525      v->RedGamma = v->GreenGamma = v->BlueGamma = 0.0;
1526      sscanf( gamma, "%f %f %f", &v->RedGamma, &v->GreenGamma, &v->BlueGamma );
1527      if (v->RedGamma<=0.0)    v->RedGamma = 1.0;
1528      if (v->GreenGamma<=0.0)  v->GreenGamma = v->RedGamma;
1529      if (v->BlueGamma<=0.0)   v->BlueGamma = v->RedGamma;
1530   }
1531   else {
1532      v->RedGamma = v->GreenGamma = v->BlueGamma = 1.0;
1533   }
1534
1535   v->ximage_flag = ximage_flag;
1536
1537#ifdef XFree86Server
1538   /* We could calculate these values by ourselves.  nplanes is either the sum
1539    * of the red, green, and blue bits or the number index bits.
1540    * ColormapEntries is either (1U << index_bits) or
1541    * (1U << max(redBits, greenBits, blueBits)).
1542    */
1543   v->nplanes = visinfo->nplanes;
1544   v->ColormapEntries = visinfo->ColormapEntries;
1545
1546   v->mesa_visual.redMask = visinfo->redMask;
1547   v->mesa_visual.greenMask = visinfo->greenMask;
1548   v->mesa_visual.blueMask = visinfo->blueMask;
1549   v->mesa_visual.visualID = visinfo->vid;
1550   v->mesa_visual.screen = 0; /* FIXME: What should be done here? */
1551#else
1552   v->mesa_visual.redMask = visinfo->red_mask;
1553   v->mesa_visual.greenMask = visinfo->green_mask;
1554   v->mesa_visual.blueMask = visinfo->blue_mask;
1555   v->mesa_visual.visualID = visinfo->visualid;
1556   v->mesa_visual.screen = visinfo->screen;
1557#endif
1558
1559#if defined(XFree86Server) || !(defined(__cplusplus) || defined(c_plusplus))
1560   v->mesa_visual.visualType = xmesa_convert_from_x_visual_type(visinfo->class);
1561#else
1562   v->mesa_visual.visualType = xmesa_convert_from_x_visual_type(visinfo->c_class);
1563#endif
1564
1565   v->mesa_visual.visualRating = visualCaveat;
1566
1567   (void) initialize_visual_and_buffer( 0, v, NULL, rgb_flag, 0, 0 );
1568
1569   {
1570      const int xclass = v->mesa_visual.visualType;
1571      if (xclass==GLX_TRUE_COLOR || xclass==GLX_DIRECT_COLOR) {
1572         red_bits   = bitcount(GET_REDMASK(v));
1573         green_bits = bitcount(GET_GREENMASK(v));
1574         blue_bits  = bitcount(GET_BLUEMASK(v));
1575         alpha_bits = 0;
1576      }
1577      else {
1578         /* this is an approximation */
1579         int depth;
1580         depth = GET_VISUAL_DEPTH(v);
1581         red_bits = depth / 3;
1582         depth -= red_bits;
1583         green_bits = depth / 2;
1584         depth -= green_bits;
1585         blue_bits = depth;
1586         alpha_bits = 0;
1587         assert( red_bits + green_bits + blue_bits == GET_VISUAL_DEPTH(v) );
1588      }
1589   }
1590
1591   if (alpha_flag && alpha_bits == 0)
1592      alpha_bits = 8;
1593
1594   _mesa_initialize_visual( &v->mesa_visual,
1595                            rgb_flag, db_flag, stereo_flag,
1596                            red_bits, green_bits,
1597                            blue_bits, alpha_bits,
1598                            v->mesa_visual.indexBits,
1599                            depth_size,
1600                            stencil_size,
1601                            accum_red_size, accum_green_size,
1602                            accum_blue_size, accum_alpha_size,
1603                            0 );
1604
1605   /* XXX minor hack */
1606   v->mesa_visual.level = level;
1607   return v;
1608}
1609
1610
1611void XMesaSetVisualDisplay( XMesaDisplay *dpy, XMesaVisual v )
1612{
1613    v->display = dpy;
1614}
1615
1616
1617void XMesaDestroyVisual( XMesaVisual v )
1618{
1619#ifndef XFree86Server
1620   FREE(v->visinfo);
1621#endif
1622   FREE(v);
1623}
1624
1625
1626
1627/**
1628 * Create a new XMesaContext.
1629 * \param v  the XMesaVisual
1630 * \param share_list  another XMesaContext with which to share display
1631 *                    lists or NULL if no sharing is wanted.
1632 * \return an XMesaContext or NULL if error.
1633 */
1634XMesaContext XMesaCreateContext( XMesaVisual v, XMesaContext share_list )
1635{
1636   static GLboolean firstTime = GL_TRUE;
1637   XMesaContext c;
1638   GLcontext *mesaCtx;
1639   struct dd_function_table functions;
1640   TNLcontext *tnl;
1641
1642   if (firstTime) {
1643      _glthread_INIT_MUTEX(_xmesa_lock);
1644      firstTime = GL_FALSE;
1645   }
1646
1647   /* Note: the XMesaContext contains a Mesa GLcontext struct (inheritance) */
1648   c = (XMesaContext) CALLOC_STRUCT(xmesa_context);
1649   if (!c)
1650      return NULL;
1651
1652   mesaCtx = &(c->mesa);
1653
1654   /* initialize with default driver functions, then plug in XMesa funcs */
1655   _mesa_init_driver_functions(&functions);
1656   xmesa_init_driver_functions(v, &functions);
1657   if (!_mesa_initialize_context(mesaCtx, &v->mesa_visual,
1658                      share_list ? &(share_list->mesa) : (GLcontext *) NULL,
1659                      &functions, (void *) c)) {
1660      FREE(c);
1661      return NULL;
1662   }
1663
1664   _mesa_enable_sw_extensions(mesaCtx);
1665   _mesa_enable_1_3_extensions(mesaCtx);
1666   _mesa_enable_1_4_extensions(mesaCtx);
1667   _mesa_enable_1_5_extensions(mesaCtx);
1668
1669   /* finish up xmesa context initializations */
1670   c->swapbytes = CHECK_BYTE_ORDER(v) ? GL_FALSE : GL_TRUE;
1671   c->xm_visual = v;
1672   c->xm_draw_buffer = NULL;   /* set later by XMesaMakeCurrent */
1673   c->xm_read_buffer = NULL;   /* set later by XMesaMakeCurrent */
1674   c->xm_buffer = NULL;   /* set later by XMesaMakeCurrent */
1675   c->display = v->display;
1676   c->pixelformat = v->dithered_pf;      /* Dithering is enabled by default */
1677
1678   /* Initialize the software rasterizer and helper modules.
1679    */
1680   _swrast_CreateContext( mesaCtx );
1681   _ac_CreateContext( mesaCtx );
1682   _tnl_CreateContext( mesaCtx );
1683   _swsetup_CreateContext( mesaCtx );
1684
1685   /* tnl setup */
1686   tnl = TNL_CONTEXT(mesaCtx);
1687   tnl->Driver.RunPipeline = _tnl_run_pipeline;
1688   /* swrast setup */
1689   xmesa_register_swrast_functions( mesaCtx );
1690   _swsetup_Wakeup(mesaCtx);
1691
1692   return c;
1693}
1694
1695
1696
1697void XMesaDestroyContext( XMesaContext c )
1698{
1699   GLcontext *mesaCtx = &c->mesa;
1700#ifdef FX
1701   if (c->xm_draw_buffer && c->xm_buffer->FXctx)
1702      fxMesaDestroyContext(c->xm_draw_buffer->FXctx);
1703#endif
1704   _swsetup_DestroyContext( mesaCtx );
1705   _swrast_DestroyContext( mesaCtx );
1706   _tnl_DestroyContext( mesaCtx );
1707   _ac_DestroyContext( mesaCtx );
1708   _mesa_free_context_data( mesaCtx );
1709   _mesa_free( c );
1710}
1711
1712
1713
1714/*
1715 * XXX this isn't a public function!  It's a hack for the 3Dfx driver.
1716 * Create a new XMesaBuffer from an X window.
1717 * Input:  v - the XMesaVisual
1718 *         w - the window
1719 *         c - the context
1720 * Return:  new XMesaBuffer or NULL if error
1721 */
1722XMesaBuffer XMesaCreateWindowBuffer2( XMesaVisual v, XMesaWindow w,
1723                                      XMesaContext c )
1724{
1725#ifndef XFree86Server
1726   XWindowAttributes attr;
1727#endif
1728#ifdef FX
1729   char *fxEnvVar;
1730#endif
1731   int client = 0;
1732
1733   XMesaBuffer b = alloc_xmesa_buffer();
1734   if (!b) {
1735      return NULL;
1736   }
1737
1738   (void) c;
1739
1740#ifdef XFree86Server
1741   client = CLIENT_ID(((XMesaDrawable)w)->id);
1742#endif
1743
1744   assert(v);
1745
1746#ifdef XFree86Server
1747   if (GET_VISUAL_DEPTH(v) != ((XMesaDrawable)w)->depth) {
1748#else
1749   XGetWindowAttributes( v->display, w, &attr );
1750
1751   if (GET_VISUAL_DEPTH(v) != attr.depth) {
1752#endif
1753      _mesa_warning(NULL, "XMesaCreateWindowBuffer: depth mismatch between visual and window!\n");
1754      return NULL;
1755   }
1756
1757   b->xm_visual = v;
1758   b->type = WINDOW;
1759   b->display = v->display;
1760#ifdef XFree86Server
1761   b->cmap = (ColormapPtr)LookupIDByType(wColormap(w), RT_COLORMAP);
1762#else
1763   if (attr.colormap) {
1764      b->cmap = attr.colormap;
1765   }
1766   else {
1767      _mesa_warning(NULL, "Window %u has no colormap!\n", (unsigned int) w);
1768      /* this is weird, a window w/out a colormap!? */
1769      /* OK, let's just allocate a new one and hope for the best */
1770      b->cmap = XCreateColormap(v->display, w, attr.visual, AllocNone);
1771   }
1772#endif
1773
1774   /* determine back buffer implementation */
1775   if (v->mesa_visual.doubleBufferMode) {
1776      if (v->ximage_flag) {
1777	 b->db_state = BACK_XIMAGE;
1778      }
1779      else {
1780	 b->db_state = BACK_PIXMAP;
1781      }
1782   }
1783   else {
1784      b->db_state = 0;
1785   }
1786
1787   _mesa_initialize_framebuffer(&b->mesa_buffer,
1788                                &v->mesa_visual,
1789                                v->mesa_visual.depthBits > 0,
1790                                v->mesa_visual.stencilBits > 0,
1791                                v->mesa_visual.accumRedBits > 0,
1792                                v->mesa_visual.alphaBits > 0 );
1793   /* XXX hack */
1794   b->mesa_buffer.UseSoftwareAuxBuffers = GL_TRUE;
1795
1796   if (!initialize_visual_and_buffer( client, v, b, v->mesa_visual.rgbMode,
1797                                      (XMesaDrawable)w, b->cmap )) {
1798      free_xmesa_buffer(client, b);
1799      return NULL;
1800   }
1801
1802#ifdef FX
1803   fxEnvVar = _mesa_getenv("MESA_GLX_FX");
1804   if (fxEnvVar) {
1805     if (fxEnvVar[0]!='d') {
1806       int attribs[100];
1807       int numAttribs = 0;
1808       int hw;
1809       if (v->mesa_visual.depthBits > 0) {
1810	 attribs[numAttribs++] = FXMESA_DEPTH_SIZE;
1811	 attribs[numAttribs++] = v->mesa_visual.depthBits;
1812       }
1813       if (v->mesa_visual.doubleBufferMode) {
1814	 attribs[numAttribs++] = FXMESA_DOUBLEBUFFER;
1815       }
1816       if (v->mesa_visual.accumRedBits > 0) {
1817	 attribs[numAttribs++] = FXMESA_ACCUM_SIZE;
1818	 attribs[numAttribs++] = v->mesa_visual.accumRedBits;
1819       }
1820       if (v->mesa_visual.stencilBits > 0) {
1821         attribs[numAttribs++] = FXMESA_STENCIL_SIZE;
1822         attribs[numAttribs++] = v->mesa_visual.stencilBits;
1823       }
1824       if (v->mesa_visual.alphaBits > 0) {
1825         attribs[numAttribs++] = FXMESA_ALPHA_SIZE;
1826         attribs[numAttribs++] = v->mesa_visual.alphaBits;
1827       }
1828       if (1) {
1829         attribs[numAttribs++] = FXMESA_SHARE_CONTEXT;
1830         attribs[numAttribs++] = (int) &(c->mesa);
1831       }
1832       attribs[numAttribs++] = FXMESA_NONE;
1833
1834       /* [dBorca] we should take an envvar for `fxMesaSelectCurrentBoard'!!! */
1835       hw = fxMesaSelectCurrentBoard(0);
1836       if ((hw == GR_SSTTYPE_VOODOO) || (hw == GR_SSTTYPE_Voodoo2)) {
1837         b->FXctx = fxMesaCreateBestContext(0, b->width, b->height, attribs);
1838         if ((v->undithered_pf!=PF_Index) && (b->backimage)) {
1839	   b->FXisHackUsable = b->FXctx ? GL_TRUE : GL_FALSE;
1840	   if (b->FXctx && (fxEnvVar[0]=='w' || fxEnvVar[0]=='W')) {
1841	     b->FXwindowHack = GL_TRUE;
1842	     FX_grSstControl(GR_CONTROL_DEACTIVATE);
1843	   }
1844           else {
1845	     b->FXwindowHack = GL_FALSE;
1846	   }
1847         }
1848       }
1849       else {
1850         if (fxEnvVar[0]=='w' || fxEnvVar[0]=='W')
1851	   b->FXctx = fxMesaCreateContext(w, GR_RESOLUTION_NONE,
1852					  GR_REFRESH_75Hz, attribs);
1853         else
1854	   b->FXctx = fxMesaCreateBestContext(0, b->width, b->height, attribs);
1855         b->FXisHackUsable = GL_FALSE;
1856         b->FXwindowHack = GL_FALSE;
1857       }
1858       /*
1859       fprintf(stderr,
1860               "voodoo %d, wid %d height %d hack: usable %d active %d\n",
1861               hw, b->width, b->height, b->FXisHackUsable, b->FXwindowHack);
1862       */
1863     }
1864   }
1865   else {
1866      _mesa_warning(NULL, "WARNING: This Mesa Library includes the Glide driver but\n");
1867      _mesa_warning(NULL, "         you have not defined the MESA_GLX_FX env. var.\n");
1868      _mesa_warning(NULL, "         (check the README.3DFX file for more information).\n\n");
1869      _mesa_warning(NULL, "         you can disable this message with a 'export MESA_GLX_FX=disable'.\n");
1870   }
1871#endif
1872
1873   return b;
1874}
1875
1876
1877XMesaBuffer XMesaCreateWindowBuffer( XMesaVisual v, XMesaWindow w )
1878{
1879   return XMesaCreateWindowBuffer2( v, w, NULL );
1880}
1881
1882
1883/**
1884 * Create a new XMesaBuffer from an X pixmap.
1885 *
1886 * \param v    the XMesaVisual
1887 * \param p    the pixmap
1888 * \param cmap the colormap, may be 0 if using a \c GLX_TRUE_COLOR or
1889 *             \c GLX_DIRECT_COLOR visual for the pixmap
1890 * \returns new XMesaBuffer or NULL if error
1891 */
1892XMesaBuffer XMesaCreatePixmapBuffer( XMesaVisual v,
1893				     XMesaPixmap p, XMesaColormap cmap )
1894{
1895   int client = 0;
1896   XMesaBuffer b = alloc_xmesa_buffer();
1897   if (!b) {
1898      return NULL;
1899   }
1900
1901
1902#ifdef XFree86Server
1903   client = CLIENT_ID(((XMesaDrawable)p)->id);
1904#endif
1905
1906   assert(v);
1907
1908   b->xm_visual = v;
1909   b->type = PIXMAP;
1910   b->display = v->display;
1911   b->cmap = cmap;
1912
1913   /* determine back buffer implementation */
1914   if (v->mesa_visual.doubleBufferMode) {
1915      if (v->ximage_flag) {
1916	 b->db_state = BACK_XIMAGE;
1917      }
1918      else {
1919	 b->db_state = BACK_PIXMAP;
1920      }
1921   }
1922   else {
1923      b->db_state = 0;
1924   }
1925
1926   _mesa_initialize_framebuffer(&b->mesa_buffer,
1927                                &v->mesa_visual,
1928                                v->mesa_visual.depthBits > 0,
1929                                v->mesa_visual.stencilBits > 0,
1930                                v->mesa_visual.accumRedBits +
1931                                v->mesa_visual.accumGreenBits +
1932                                v->mesa_visual.accumBlueBits > 0,
1933                                v->mesa_visual.alphaBits > 0 );
1934
1935   if (!initialize_visual_and_buffer(client, v, b, v->mesa_visual.rgbMode,
1936				     (XMesaDrawable)p, cmap)) {
1937      free_xmesa_buffer(client, b);
1938      return NULL;
1939   }
1940
1941   return b;
1942}
1943
1944
1945
1946XMesaBuffer XMesaCreatePBuffer( XMesaVisual v, XMesaColormap cmap,
1947                                unsigned int width, unsigned int height )
1948{
1949#ifdef XFree86Server
1950   return 0;
1951#else
1952   int client = 0;
1953   XMesaWindow root;
1954   XMesaDrawable drawable;  /* X Pixmap Drawable */
1955   XMesaBuffer b = alloc_xmesa_buffer();
1956   if (!b) {
1957      return NULL;
1958   }
1959
1960   b->xm_visual = v;
1961   b->type = PBUFFER;
1962   b->display = v->display;
1963   b->cmap = cmap;
1964
1965   /* allocate pixmap for front buffer */
1966   root = RootWindow( v->display, v->visinfo->screen );
1967   drawable = XCreatePixmap( v->display, root, width, height, v->visinfo->depth );
1968
1969   /* determine back buffer implementation */
1970   if (v->mesa_visual.doubleBufferMode) {
1971      if (v->ximage_flag) {
1972	 b->db_state = BACK_XIMAGE;
1973      }
1974      else {
1975	 b->db_state = BACK_PIXMAP;
1976      }
1977   }
1978   else {
1979      b->db_state = 0;
1980   }
1981
1982   _mesa_initialize_framebuffer(&b->mesa_buffer,
1983                                &v->mesa_visual,
1984                                v->mesa_visual.depthBits > 0,
1985                                v->mesa_visual.stencilBits > 0,
1986                                v->mesa_visual.accumRedBits +
1987                                v->mesa_visual.accumGreenBits +
1988                                v->mesa_visual.accumBlueBits > 0,
1989                                v->mesa_visual.alphaBits > 0 );
1990
1991   if (!initialize_visual_and_buffer(client, v, b, v->mesa_visual.rgbMode,
1992				     drawable, cmap)) {
1993      free_xmesa_buffer(client, b);
1994      return NULL;
1995   }
1996
1997   return b;
1998#endif
1999}
2000
2001
2002
2003/*
2004 * Deallocate an XMesaBuffer structure and all related info.
2005 */
2006void XMesaDestroyBuffer( XMesaBuffer b )
2007{
2008   int client = 0;
2009
2010#ifdef XFree86Server
2011   if (b->frontbuffer)
2012       client = CLIENT_ID(b->frontbuffer->id);
2013#endif
2014
2015   if (b->gc)  XMesaFreeGC( b->xm_visual->display, b->gc );
2016   if (b->cleargc)  XMesaFreeGC( b->xm_visual->display, b->cleargc );
2017   if (b->swapgc)  XMesaFreeGC( b->xm_visual->display, b->swapgc );
2018
2019   if (b->backimage) {
2020#if defined(USE_XSHM) && !defined(XFree86Server)
2021       if (b->shm) {
2022	   XShmDetach( b->xm_visual->display, &b->shminfo );
2023	   XDestroyImage( b->backimage );
2024	   shmdt( b->shminfo.shmaddr );
2025       }
2026       else
2027#endif
2028	   XMesaDestroyImage( b->backimage );
2029   }
2030   if (b->backpixmap) {
2031      XMesaFreePixmap( b->xm_visual->display, b->backpixmap );
2032      if (b->xm_visual->hpcr_clear_flag) {
2033	XMesaFreePixmap( b->xm_visual->display,
2034			 b->xm_visual->hpcr_clear_pixmap );
2035	XMesaDestroyImage( b->xm_visual->hpcr_clear_ximage );
2036      }
2037   }
2038   if (b->rowimage) {
2039      FREE( b->rowimage->data );
2040      b->rowimage->data = NULL;
2041      XMesaDestroyImage( b->rowimage );
2042   }
2043
2044   free_xmesa_buffer(client, b);
2045}
2046
2047
2048
2049/*
2050 * Bind buffer b to context c and make c the current rendering context.
2051 */
2052GLboolean XMesaMakeCurrent( XMesaContext c, XMesaBuffer b )
2053{
2054   return XMesaMakeCurrent2( c, b, b );
2055}
2056
2057
2058/*
2059 * Bind buffer b to context c and make c the current rendering context.
2060 */
2061GLboolean XMesaMakeCurrent2( XMesaContext c, XMesaBuffer drawBuffer,
2062                             XMesaBuffer readBuffer )
2063{
2064   if (c) {
2065      if (!drawBuffer || !readBuffer)
2066         return GL_FALSE;  /* must specify buffers! */
2067
2068#ifdef FX
2069      if (drawBuffer->FXctx) {
2070         fxMesaMakeCurrent(drawBuffer->FXctx);
2071
2072         c->xm_draw_buffer = drawBuffer;
2073         c->xm_read_buffer = readBuffer;
2074         c->xm_buffer = drawBuffer;
2075
2076         return GL_TRUE;
2077      }
2078#endif
2079      if (&(c->mesa) == _mesa_get_current_context()
2080          && c->xm_draw_buffer == drawBuffer
2081          && c->xm_read_buffer == readBuffer
2082          && c->xm_draw_buffer->wasCurrent) {
2083         /* same context and buffer, do nothing */
2084         return GL_TRUE;
2085      }
2086
2087      c->xm_draw_buffer = drawBuffer;
2088      c->xm_read_buffer = readBuffer;
2089      c->xm_buffer = drawBuffer;
2090
2091      _mesa_make_current2(&(c->mesa),
2092                          &drawBuffer->mesa_buffer,
2093                          &readBuffer->mesa_buffer);
2094
2095      if (c->mesa.Viewport.Width == 0) {
2096	 /* initialize viewport to window size */
2097	 _mesa_Viewport( 0, 0, drawBuffer->width, drawBuffer->height );
2098	 c->mesa.Scissor.Width = drawBuffer->width;
2099	 c->mesa.Scissor.Height = drawBuffer->height;
2100      }
2101
2102      if (c->xm_visual->mesa_visual.rgbMode) {
2103         /*
2104          * Must recompute and set these pixel values because colormap
2105          * can be different for different windows.
2106          */
2107         c->clearpixel = xmesa_color_to_pixel( c,
2108                                               c->clearcolor[0],
2109                                               c->clearcolor[1],
2110                                               c->clearcolor[2],
2111                                               c->clearcolor[3],
2112                                               c->xm_visual->undithered_pf);
2113         XMesaSetForeground(c->display, c->xm_draw_buffer->cleargc, c->clearpixel);
2114      }
2115
2116      /* Solution to Stephane Rehel's problem with glXReleaseBuffersMESA(): */
2117      c->xm_draw_buffer->wasCurrent = GL_TRUE;
2118   }
2119   else {
2120      /* Detach */
2121      _mesa_make_current2( NULL, NULL, NULL );
2122   }
2123   return GL_TRUE;
2124}
2125
2126
2127/*
2128 * Unbind the context c from its buffer.
2129 */
2130GLboolean XMesaUnbindContext( XMesaContext c )
2131{
2132   /* A no-op for XFree86 integration purposes */
2133   return GL_TRUE;
2134}
2135
2136
2137XMesaContext XMesaGetCurrentContext( void )
2138{
2139   GET_CURRENT_CONTEXT(ctx);
2140   if (ctx) {
2141      XMesaContext xmesa = XMESA_CONTEXT(ctx);
2142      return xmesa;
2143   }
2144   else {
2145      return 0;
2146   }
2147}
2148
2149
2150XMesaBuffer XMesaGetCurrentBuffer( void )
2151{
2152   GET_CURRENT_CONTEXT(ctx);
2153   if (ctx) {
2154      XMesaContext xmesa = XMESA_CONTEXT(ctx);
2155      return xmesa->xm_draw_buffer;
2156   }
2157   else {
2158      return 0;
2159   }
2160}
2161
2162
2163/* New in Mesa 3.1 */
2164XMesaBuffer XMesaGetCurrentReadBuffer( void )
2165{
2166   GET_CURRENT_CONTEXT(ctx);
2167   if (ctx) {
2168      XMesaContext xmesa = XMESA_CONTEXT(ctx);
2169      return xmesa->xm_read_buffer;
2170   }
2171   else {
2172      return 0;
2173   }
2174}
2175
2176
2177GLboolean XMesaForceCurrent(XMesaContext c)
2178{
2179   if (c) {
2180      if (&(c->mesa) != _mesa_get_current_context()) {
2181	 _mesa_make_current(&(c->mesa), &c->xm_draw_buffer->mesa_buffer);
2182      }
2183   }
2184   else {
2185      _mesa_make_current(NULL, NULL);
2186   }
2187   return GL_TRUE;
2188}
2189
2190
2191GLboolean XMesaLoseCurrent(XMesaContext c)
2192{
2193   (void) c;
2194   _mesa_make_current(NULL, NULL);
2195   return GL_TRUE;
2196}
2197
2198
2199/*
2200 * Switch 3Dfx support hack between window and full-screen mode.
2201 */
2202GLboolean XMesaSetFXmode( GLint mode )
2203{
2204#ifdef FX
2205   const char *fx = _mesa_getenv("MESA_GLX_FX");
2206   if (fx && fx[0] != 'd') {
2207      GET_CURRENT_CONTEXT(ctx);
2208      GrHwConfiguration hw;
2209      if (!FX_grSstQueryHardware(&hw)) {
2210         /*fprintf(stderr, "!grSstQueryHardware\n");*/
2211         return GL_FALSE;
2212      }
2213      if (hw.num_sst < 1) {
2214         /*fprintf(stderr, "hw.num_sst < 1\n");*/
2215         return GL_FALSE;
2216      }
2217      if (ctx) {
2218         /* [dBorca] Hack alert:
2219	  * oh, this is sooo wrong: ctx above is
2220	  * really an fxMesaContext, not an XMesaContext
2221	  */
2222         XMesaContext xmesa = XMESA_CONTEXT(ctx);
2223         if (mode == XMESA_FX_WINDOW) {
2224	    if (xmesa->xm_draw_buffer->FXisHackUsable) {
2225	       FX_grSstControl(GR_CONTROL_DEACTIVATE);
2226	       xmesa->xm_draw_buffer->FXwindowHack = GL_TRUE;
2227	       return GL_TRUE;
2228	    }
2229	 }
2230	 else if (mode == XMESA_FX_FULLSCREEN) {
2231	    FX_grSstControl(GR_CONTROL_ACTIVATE);
2232	    xmesa->xm_draw_buffer->FXwindowHack = GL_FALSE;
2233	    return GL_TRUE;
2234	 }
2235	 else {
2236	    /* Error: Bad mode value */
2237	 }
2238      }
2239   }
2240   /*fprintf(stderr, "fallthrough\n");*/
2241#else
2242   (void) mode;
2243#endif
2244   return GL_FALSE;
2245}
2246
2247
2248
2249#ifdef FX
2250/*
2251 * Read image from VooDoo frame buffer into X/Mesa's back XImage.
2252 */
2253static void FXgetImage( XMesaBuffer b )
2254{
2255   GET_CURRENT_CONTEXT(ctx);
2256   static unsigned short pixbuf[MAX_WIDTH];
2257   GLuint x, y;
2258   int xpos, ypos;
2259   XMesaWindow root;
2260   unsigned int bw, depth, width, height;
2261   XMesaContext xmesa = XMESA_CONTEXT(ctx);
2262
2263#ifdef XFree86Server
2264   x = b->frontbuffer->x;
2265   y = b->frontbuffer->y;
2266   width = b->frontbuffer->width;
2267   height = b->frontbuffer->height;
2268   depth = b->frontbuffer->depth;
2269#else
2270   XGetGeometry( b->xm_visual->display, b->frontbuffer,
2271                 &root, &xpos, &ypos, &width, &height, &bw, &depth);
2272#endif
2273   if (b->width != width || b->height != height) {
2274      b->width = MIN2((int)width, b->FXctx->width);
2275      b->height = MIN2((int)height, b->FXctx->height);
2276      if (b->width & 1)
2277         b->width--;  /* prevent odd width */
2278      xmesa_alloc_back_buffer( b );
2279   }
2280
2281   /* [dBorca] we're always in the right GR_COLORFORMAT... aren't we? */
2282   /* grLfbWriteColorFormat(GR_COLORFORMAT_ARGB); */
2283   if (b->xm_visual->undithered_pf==PF_5R6G5B) {
2284      /* Special case: 16bpp RGB */
2285      grLfbReadRegion( GR_BUFFER_FRONTBUFFER,       /* src buffer */
2286                       0, b->FXctx->height - b->height,  /*pos*/
2287                       b->width, b->height,         /* size */
2288                       b->width * sizeof(GLushort), /* stride */
2289                       b->backimage->data);         /* dest buffer */
2290   }
2291   else if (b->xm_visual->dithered_pf==PF_Dither
2292	    && GET_VISUAL_DEPTH(b->xm_visual)==8) {
2293      /* Special case: 8bpp RGB */
2294      for (y=0;y<b->height;y++) {
2295         GLubyte *ptr = (GLubyte*) b->backimage->data
2296                        + b->backimage->bytes_per_line * y;
2297         XDITHER_SETUP(y);
2298
2299         /* read row from 3Dfx frame buffer */
2300         grLfbReadRegion( GR_BUFFER_FRONTBUFFER,
2301                          0, b->FXctx->height-(b->height-y),
2302                          b->width, 1,
2303                          0,
2304                          pixbuf );
2305
2306         /* write to XImage back buffer */
2307         for (x=0;x<b->width;x++) {
2308            GLubyte r = (pixbuf[x] & 0xf800) >> 8;
2309            GLubyte g = (pixbuf[x] & 0x07e0) >> 3;
2310            GLubyte b = (pixbuf[x] & 0x001f) << 3;
2311            *ptr++ = XDITHER( x, r, g, b);
2312         }
2313      }
2314   }
2315   else {
2316      /* General case: slow! */
2317      for (y=0;y<b->height;y++) {
2318         /* read row from 3Dfx frame buffer */
2319         grLfbReadRegion( GR_BUFFER_FRONTBUFFER,
2320                          0, b->FXctx->height-(b->height-y),
2321                          b->width, 1,
2322                          0,
2323                          pixbuf );
2324
2325         /* write to XImage back buffer */
2326         for (x=0;x<b->width;x++) {
2327            XMesaPutPixel(b->backimage,x,y,
2328			  xmesa_color_to_pixel(xmesa,
2329					       (pixbuf[x] & 0xf800) >> 8,
2330					       (pixbuf[x] & 0x07e0) >> 3,
2331					       (pixbuf[x] & 0x001f) << 3,
2332					       0xff,
2333                                               b->xm_visual->undithered_pf));
2334         }
2335      }
2336   }
2337   /* grLfbWriteColorFormat(GR_COLORFORMAT_ABGR); */
2338}
2339#endif
2340
2341
2342/*
2343 * Copy the back buffer to the front buffer.  If there's no back buffer
2344 * this is a no-op.
2345 */
2346void XMesaSwapBuffers( XMesaBuffer b )
2347{
2348   GET_CURRENT_CONTEXT(ctx);
2349
2350   /* If we're swapping the buffer associated with the current context
2351    * we have to flush any pending rendering commands first.
2352    */
2353   if (ctx && ctx->DrawBuffer == &(b->mesa_buffer))
2354      _mesa_notifySwapBuffers(ctx);
2355
2356   if (b->db_state) {
2357#ifdef FX
2358      if (b->FXctx) {
2359         fxMesaSwapBuffers();
2360
2361         if (b->FXwindowHack)
2362            FXgetImage(b);
2363         else
2364            return;
2365      }
2366#endif
2367     if (b->backimage) {
2368	 /* Copy Ximage from host's memory to server's window */
2369#if defined(USE_XSHM) && !defined(XFree86Server)
2370	 if (b->shm) {
2371            /*_glthread_LOCK_MUTEX(_xmesa_lock);*/
2372	    XShmPutImage( b->xm_visual->display, b->frontbuffer,
2373			  b->swapgc,
2374			  b->backimage, 0, 0,
2375			  0, 0, b->width, b->height, False );
2376            /*_glthread_UNLOCK_MUTEX(_xmesa_lock);*/
2377	 }
2378	 else
2379#endif
2380         {
2381            /*_glthread_LOCK_MUTEX(_xmesa_lock);*/
2382            XMesaPutImage( b->xm_visual->display, b->frontbuffer,
2383			   b->swapgc,
2384			   b->backimage, 0, 0,
2385			   0, 0, b->width, b->height );
2386            /*_glthread_UNLOCK_MUTEX(_xmesa_lock);*/
2387         }
2388      }
2389      else {
2390	 /* Copy pixmap to window on server */
2391         /*_glthread_LOCK_MUTEX(_xmesa_lock);*/
2392	 XMesaCopyArea( b->xm_visual->display,
2393			b->backpixmap,   /* source drawable */
2394			b->frontbuffer,  /* dest. drawable */
2395			b->swapgc,
2396			0, 0, b->width, b->height,  /* source region */
2397			0, 0                 /* dest region */
2398		      );
2399         /*_glthread_UNLOCK_MUTEX(_xmesa_lock);*/
2400      }
2401   }
2402#if !defined(XFree86Server)
2403   XSync( b->xm_visual->display, False );
2404#endif
2405}
2406
2407
2408
2409/*
2410 * Copy sub-region of back buffer to front buffer
2411 */
2412void XMesaCopySubBuffer( XMesaBuffer b, int x, int y, int width, int height )
2413{
2414   GET_CURRENT_CONTEXT(ctx);
2415
2416   /* If we're swapping the buffer associated with the current context
2417    * we have to flush any pending rendering commands first.
2418    */
2419   if (ctx && ctx->DrawBuffer == &(b->mesa_buffer))
2420      _mesa_notifySwapBuffers(ctx);
2421
2422   if (b->db_state) {
2423      int yTop = b->height - y - height;
2424#ifdef FX
2425      if (b->FXctx) {
2426         fxMesaSwapBuffers();
2427         if (b->FXwindowHack)
2428            FXgetImage(b);
2429         else
2430            return;
2431      }
2432#endif
2433      if (b->backimage) {
2434         /* Copy Ximage from host's memory to server's window */
2435#if defined(USE_XSHM) && !defined(XFree86Server)
2436         if (b->shm) {
2437            /* XXX assuming width and height aren't too large! */
2438            XShmPutImage( b->xm_visual->display, b->frontbuffer,
2439                          b->swapgc,
2440                          b->backimage, x, yTop,
2441                          x, yTop, width, height, False );
2442            /* wait for finished event??? */
2443         }
2444         else
2445#endif
2446         {
2447            /* XXX assuming width and height aren't too large! */
2448            XMesaPutImage( b->xm_visual->display, b->frontbuffer,
2449			   b->swapgc,
2450			   b->backimage, x, yTop,
2451			   x, yTop, width, height );
2452         }
2453      }
2454      else {
2455         /* Copy pixmap to window on server */
2456         XMesaCopyArea( b->xm_visual->display,
2457			b->backpixmap,           /* source drawable */
2458			b->frontbuffer,          /* dest. drawable */
2459			b->swapgc,
2460			x, yTop, width, height,  /* source region */
2461			x, yTop                  /* dest region */
2462                      );
2463      }
2464   }
2465}
2466
2467
2468/*
2469 * Return a pointer to the XMesa backbuffer Pixmap or XImage.  This function
2470 * is a way to get "under the hood" of X/Mesa so one can manipulate the
2471 * back buffer directly.
2472 * Output:  pixmap - pointer to back buffer's Pixmap, or 0
2473 *          ximage - pointer to back buffer's XImage, or NULL
2474 * Return:  GL_TRUE = context is double buffered
2475 *          GL_FALSE = context is single buffered
2476 */
2477GLboolean XMesaGetBackBuffer( XMesaBuffer b,
2478                              XMesaPixmap *pixmap,
2479                              XMesaImage **ximage )
2480{
2481   if (b->db_state) {
2482      if (pixmap)  *pixmap = b->backpixmap;
2483      if (ximage)  *ximage = b->backimage;
2484      return GL_TRUE;
2485   }
2486   else {
2487      *pixmap = 0;
2488      *ximage = NULL;
2489      return GL_FALSE;
2490   }
2491}
2492
2493
2494/*
2495 * Return the depth buffer associated with an XMesaBuffer.
2496 * Input:  b - the XMesa buffer handle
2497 * Output:  width, height - size of buffer in pixels
2498 *          bytesPerValue - bytes per depth value (2 or 4)
2499 *          buffer - pointer to depth buffer values
2500 * Return:  GL_TRUE or GL_FALSE to indicate success or failure.
2501 */
2502GLboolean XMesaGetDepthBuffer( XMesaBuffer b, GLint *width, GLint *height,
2503                               GLint *bytesPerValue, void **buffer )
2504{
2505   if (!b->mesa_buffer.DepthBuffer) {
2506      *width = 0;
2507      *height = 0;
2508      *bytesPerValue = 0;
2509      *buffer = 0;
2510      return GL_FALSE;
2511   }
2512   else {
2513      *width = b->mesa_buffer.Width;
2514      *height = b->mesa_buffer.Height;
2515      *bytesPerValue = sizeof(GLdepth);
2516      *buffer = b->mesa_buffer.DepthBuffer;
2517      return GL_TRUE;
2518   }
2519}
2520
2521
2522void XMesaFlush( XMesaContext c )
2523{
2524   if (c && c->xm_visual) {
2525#ifdef XFree86Server
2526      /* NOT_NEEDED */
2527#else
2528      XSync( c->xm_visual->display, False );
2529#endif
2530   }
2531}
2532
2533
2534
2535const char *XMesaGetString( XMesaContext c, int name )
2536{
2537   (void) c;
2538   if (name==XMESA_VERSION) {
2539      return "5.0";
2540   }
2541   else if (name==XMESA_EXTENSIONS) {
2542      return "";
2543   }
2544   else {
2545      return NULL;
2546   }
2547}
2548
2549
2550
2551XMesaBuffer XMesaFindBuffer( XMesaDisplay *dpy, XMesaDrawable d )
2552{
2553   XMesaBuffer b;
2554   for (b=XMesaBufferList; b; b=b->Next) {
2555      if (b->frontbuffer==d && b->display==dpy) {
2556         return b;
2557      }
2558   }
2559   return NULL;
2560}
2561
2562
2563
2564/*
2565 * Look for XMesaBuffers whose X window has been destroyed.
2566 * Deallocate any such XMesaBuffers.
2567 */
2568void XMesaGarbageCollect( void )
2569{
2570   XMesaBuffer b, next;
2571   for (b=XMesaBufferList; b; b=next) {
2572      next = b->Next;
2573      if (b->display && b->frontbuffer && b->type == WINDOW) {
2574#ifdef XFree86Server
2575	 /* NOT_NEEDED */
2576#else
2577         XSync(b->display, False);
2578         if (!window_exists( b->display, b->frontbuffer )) {
2579            /* found a dead window, free the ancillary info */
2580            XMesaDestroyBuffer( b );
2581         }
2582#endif
2583      }
2584   }
2585}
2586
2587
2588void XMesaReset( void )
2589{
2590    while (XMesaBufferList)
2591	XMesaDestroyBuffer(XMesaBufferList);
2592
2593    XMesaBufferList = NULL;
2594}
2595
2596
2597unsigned long XMesaDitherColor( XMesaContext xmesa, GLint x, GLint y,
2598                                GLfloat red, GLfloat green,
2599                                GLfloat blue, GLfloat alpha )
2600{
2601   GLint r = (GLint) (red   * 255.0F);
2602   GLint g = (GLint) (green * 255.0F);
2603   GLint b = (GLint) (blue  * 255.0F);
2604   GLint a = (GLint) (alpha * 255.0F);
2605
2606   switch (xmesa->pixelformat) {
2607      case PF_Index:
2608         return 0;
2609      case PF_Truecolor:
2610         {
2611            unsigned long p;
2612            PACK_TRUECOLOR( p, r, g, b );
2613            return p;
2614         }
2615      case PF_8A8B8G8R:
2616         return PACK_8A8B8G8R( r, g, b, a );
2617      case PF_8R8G8B:
2618         return PACK_8R8G8B( r, g, b );
2619      case PF_5R6G5B:
2620         return PACK_5R6G5B( r, g, b );
2621      case PF_Dither:
2622         {
2623            DITHER_SETUP;
2624            return DITHER( x, y, r, g, b );
2625         }
2626      case PF_1Bit:
2627         /* 382 = (3*255)/2 */
2628         return ((r+g+b) > 382) ^ xmesa->xm_visual->bitFlip;
2629      case PF_HPCR:
2630         return DITHER_HPCR(x, y, r, g, b);
2631      case PF_Lookup:
2632         {
2633            LOOKUP_SETUP;
2634            return LOOKUP( r, g, b );
2635         }
2636      case PF_Grayscale:
2637         return GRAY_RGB( r, g, b );
2638      case PF_Dither_5R6G5B:
2639         /* fall through */
2640      case PF_Dither_True:
2641         {
2642            unsigned long p;
2643            PACK_TRUEDITHER(p, x, y, r, g, b);
2644            return p;
2645         }
2646      default:
2647         _mesa_problem(NULL, "Bad pixel format in XMesaDitherColor");
2648   }
2649   return 0;
2650}
2651
2652
2653/*
2654 * This is typically called when the window size changes and we need
2655 * to reallocate the buffer's back/depth/stencil/accum buffers.
2656 */
2657void XMesaResizeBuffers( XMesaBuffer b )
2658{
2659   xmesa_resize_buffers( &(b->mesa_buffer) );
2660
2661}
2662
2663