xm_api.c revision 3c9faa448ccef15a514a5580fe76838822dd2a9e
1/*
2 * Mesa 3-D graphics library
3 * Version:  6.3
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      if (!b->rowimage)
1345         return GL_FALSE;
1346   }
1347
1348   return GL_TRUE;
1349}
1350
1351
1352
1353/*
1354 * Convert an RGBA color to a pixel value.
1355 */
1356unsigned long
1357xmesa_color_to_pixel( XMesaContext xmesa, GLubyte r, GLubyte g, GLubyte b, GLubyte a,
1358                      GLuint pixelFormat)
1359{
1360   switch (pixelFormat) {
1361      case PF_Index:
1362         return 0;
1363      case PF_Truecolor:
1364         {
1365            unsigned long p;
1366            PACK_TRUECOLOR( p, r, g, b );
1367            return p;
1368         }
1369      case PF_8A8B8G8R:
1370         return PACK_8A8B8G8R( r, g, b, a );
1371      case PF_8R8G8B:
1372         /* fall through */
1373      case PF_8R8G8B24:
1374         return PACK_8R8G8B( r, g, b );
1375      case PF_5R6G5B:
1376         return PACK_5R6G5B( r, g, b );
1377      case PF_Dither:
1378         {
1379            DITHER_SETUP;
1380            return DITHER( 1, 0, r, g, b );
1381         }
1382      case PF_1Bit:
1383         /* 382 = (3*255)/2 */
1384         return ((r+g+b) > 382) ^ xmesa->xm_visual->bitFlip;
1385      case PF_HPCR:
1386         return DITHER_HPCR(1, 1, r, g, b);
1387      case PF_Lookup:
1388         {
1389            LOOKUP_SETUP;
1390            return LOOKUP( r, g, b );
1391         }
1392      case PF_Grayscale:
1393         return GRAY_RGB( r, g, b );
1394      case PF_Dither_True:
1395         /* fall through */
1396      case PF_Dither_5R6G5B:
1397         {
1398            unsigned long p;
1399            PACK_TRUEDITHER(p, 1, 0, r, g, b);
1400            return p;
1401         }
1402      default:
1403         _mesa_problem(NULL, "Bad pixel format in xmesa_color_to_pixel");
1404   }
1405   return 0;
1406}
1407
1408
1409#define NUM_VISUAL_TYPES   6
1410
1411/**
1412 * Convert an X visual type to a GLX visual type.
1413 *
1414 * \param visualType X visual type (i.e., \c TrueColor, \c StaticGray, etc.)
1415 *        to be converted.
1416 * \return If \c visualType is a valid X visual type, a GLX visual type will
1417 *         be returned.  Otherwise \c GLX_NONE will be returned.
1418 *
1419 * \note
1420 * This code was lifted directly from lib/GL/glx/glcontextmodes.c in the
1421 * DRI CVS tree.
1422 */
1423static GLint
1424xmesa_convert_from_x_visual_type( int visualType )
1425{
1426    static const int glx_visual_types[ NUM_VISUAL_TYPES ] = {
1427	GLX_STATIC_GRAY,  GLX_GRAY_SCALE,
1428	GLX_STATIC_COLOR, GLX_PSEUDO_COLOR,
1429	GLX_TRUE_COLOR,   GLX_DIRECT_COLOR
1430    };
1431
1432    return ( (unsigned) visualType < NUM_VISUAL_TYPES )
1433	? glx_visual_types[ visualType ] : GLX_NONE;
1434}
1435
1436
1437/**********************************************************************/
1438/*****                       Public Functions                     *****/
1439/**********************************************************************/
1440
1441
1442/*
1443 * Create a new X/Mesa visual.
1444 * Input:  display - X11 display
1445 *         visinfo - an XVisualInfo pointer
1446 *         rgb_flag - GL_TRUE = RGB mode,
1447 *                    GL_FALSE = color index mode
1448 *         alpha_flag - alpha buffer requested?
1449 *         db_flag - GL_TRUE = double-buffered,
1450 *                   GL_FALSE = single buffered
1451 *         stereo_flag - stereo visual?
1452 *         ximage_flag - GL_TRUE = use an XImage for back buffer,
1453 *                       GL_FALSE = use an off-screen pixmap for back buffer
1454 *         depth_size - requested bits/depth values, or zero
1455 *         stencil_size - requested bits/stencil values, or zero
1456 *         accum_red_size - requested bits/red accum values, or zero
1457 *         accum_green_size - requested bits/green accum values, or zero
1458 *         accum_blue_size - requested bits/blue accum values, or zero
1459 *         accum_alpha_size - requested bits/alpha accum values, or zero
1460 *         num_samples - number of samples/pixel if multisampling, or zero
1461 *         level - visual level, usually 0
1462 *         visualCaveat - ala the GLX extension, usually GLX_NONE
1463 * Return;  a new XMesaVisual or 0 if error.
1464 */
1465XMesaVisual XMesaCreateVisual( XMesaDisplay *display,
1466                               XMesaVisualInfo visinfo,
1467                               GLboolean rgb_flag,
1468                               GLboolean alpha_flag,
1469                               GLboolean db_flag,
1470                               GLboolean stereo_flag,
1471                               GLboolean ximage_flag,
1472                               GLint depth_size,
1473                               GLint stencil_size,
1474                               GLint accum_red_size,
1475                               GLint accum_green_size,
1476                               GLint accum_blue_size,
1477                               GLint accum_alpha_size,
1478                               GLint num_samples,
1479                               GLint level,
1480                               GLint visualCaveat )
1481{
1482   char *gamma;
1483   XMesaVisual v;
1484   GLint red_bits, green_bits, blue_bits, alpha_bits;
1485
1486   /* For debugging only */
1487   if (_mesa_getenv("MESA_XSYNC")) {
1488      /* This makes debugging X easier.
1489       * In your debugger, set a breakpoint on _XError to stop when an
1490       * X protocol error is generated.
1491       */
1492#ifdef XFree86Server
1493      /* NOT_NEEDED */
1494#else
1495      XSynchronize( display, 1 );
1496#endif
1497   }
1498
1499   v = (XMesaVisual) CALLOC_STRUCT(xmesa_visual);
1500   if (!v) {
1501      return NULL;
1502   }
1503
1504   /*
1505    * In the X server, NULL is passed in for the display.  It will have
1506    * to be set before using this visual.  See XMesaSetVisualDisplay()
1507    * below.
1508    */
1509   v->display = display;
1510
1511   /* Save a copy of the XVisualInfo struct because the user may XFREE()
1512    * the struct but we may need some of the information contained in it
1513    * at a later time.
1514    */
1515#ifndef XFree86Server
1516   v->visinfo = (XVisualInfo *) MALLOC(sizeof(*visinfo));
1517   if(!v->visinfo) {
1518      FREE(v);
1519      return NULL;
1520   }
1521   MEMCPY(v->visinfo, visinfo, sizeof(*visinfo));
1522#endif
1523
1524   /* check for MESA_GAMMA environment variable */
1525   gamma = _mesa_getenv("MESA_GAMMA");
1526   if (gamma) {
1527      v->RedGamma = v->GreenGamma = v->BlueGamma = 0.0;
1528      sscanf( gamma, "%f %f %f", &v->RedGamma, &v->GreenGamma, &v->BlueGamma );
1529      if (v->RedGamma<=0.0)    v->RedGamma = 1.0;
1530      if (v->GreenGamma<=0.0)  v->GreenGamma = v->RedGamma;
1531      if (v->BlueGamma<=0.0)   v->BlueGamma = v->RedGamma;
1532   }
1533   else {
1534      v->RedGamma = v->GreenGamma = v->BlueGamma = 1.0;
1535   }
1536
1537   v->ximage_flag = ximage_flag;
1538
1539#ifdef XFree86Server
1540   /* We could calculate these values by ourselves.  nplanes is either the sum
1541    * of the red, green, and blue bits or the number index bits.
1542    * ColormapEntries is either (1U << index_bits) or
1543    * (1U << max(redBits, greenBits, blueBits)).
1544    */
1545   v->nplanes = visinfo->nplanes;
1546   v->ColormapEntries = visinfo->ColormapEntries;
1547
1548   v->mesa_visual.redMask = visinfo->redMask;
1549   v->mesa_visual.greenMask = visinfo->greenMask;
1550   v->mesa_visual.blueMask = visinfo->blueMask;
1551   v->mesa_visual.visualID = visinfo->vid;
1552   v->mesa_visual.screen = 0; /* FIXME: What should be done here? */
1553#else
1554   v->mesa_visual.redMask = visinfo->red_mask;
1555   v->mesa_visual.greenMask = visinfo->green_mask;
1556   v->mesa_visual.blueMask = visinfo->blue_mask;
1557   v->mesa_visual.visualID = visinfo->visualid;
1558   v->mesa_visual.screen = visinfo->screen;
1559#endif
1560
1561#if defined(XFree86Server) || !(defined(__cplusplus) || defined(c_plusplus))
1562   v->mesa_visual.visualType = xmesa_convert_from_x_visual_type(visinfo->class);
1563#else
1564   v->mesa_visual.visualType = xmesa_convert_from_x_visual_type(visinfo->c_class);
1565#endif
1566
1567   v->mesa_visual.visualRating = visualCaveat;
1568
1569   (void) initialize_visual_and_buffer( 0, v, NULL, rgb_flag, 0, 0 );
1570
1571   {
1572      const int xclass = v->mesa_visual.visualType;
1573      if (xclass==GLX_TRUE_COLOR || xclass==GLX_DIRECT_COLOR) {
1574         red_bits   = bitcount(GET_REDMASK(v));
1575         green_bits = bitcount(GET_GREENMASK(v));
1576         blue_bits  = bitcount(GET_BLUEMASK(v));
1577         alpha_bits = 0;
1578      }
1579      else {
1580         /* this is an approximation */
1581         int depth;
1582         depth = GET_VISUAL_DEPTH(v);
1583         red_bits = depth / 3;
1584         depth -= red_bits;
1585         green_bits = depth / 2;
1586         depth -= green_bits;
1587         blue_bits = depth;
1588         alpha_bits = 0;
1589         assert( red_bits + green_bits + blue_bits == GET_VISUAL_DEPTH(v) );
1590      }
1591   }
1592
1593   if (alpha_flag && alpha_bits == 0)
1594      alpha_bits = 8;
1595
1596   _mesa_initialize_visual( &v->mesa_visual,
1597                            rgb_flag, db_flag, stereo_flag,
1598                            red_bits, green_bits,
1599                            blue_bits, alpha_bits,
1600                            v->mesa_visual.indexBits,
1601                            depth_size,
1602                            stencil_size,
1603                            accum_red_size, accum_green_size,
1604                            accum_blue_size, accum_alpha_size,
1605                            0 );
1606
1607   /* XXX minor hack */
1608   v->mesa_visual.level = level;
1609   return v;
1610}
1611
1612
1613void XMesaSetVisualDisplay( XMesaDisplay *dpy, XMesaVisual v )
1614{
1615    v->display = dpy;
1616}
1617
1618
1619void XMesaDestroyVisual( XMesaVisual v )
1620{
1621#ifndef XFree86Server
1622   FREE(v->visinfo);
1623#endif
1624   FREE(v);
1625}
1626
1627
1628
1629/**
1630 * Create a new XMesaContext.
1631 * \param v  the XMesaVisual
1632 * \param share_list  another XMesaContext with which to share display
1633 *                    lists or NULL if no sharing is wanted.
1634 * \return an XMesaContext or NULL if error.
1635 */
1636XMesaContext XMesaCreateContext( XMesaVisual v, XMesaContext share_list )
1637{
1638   static GLboolean firstTime = GL_TRUE;
1639   XMesaContext c;
1640   GLcontext *mesaCtx;
1641   struct dd_function_table functions;
1642   TNLcontext *tnl;
1643
1644   if (firstTime) {
1645      _glthread_INIT_MUTEX(_xmesa_lock);
1646      firstTime = GL_FALSE;
1647   }
1648
1649   /* Note: the XMesaContext contains a Mesa GLcontext struct (inheritance) */
1650   c = (XMesaContext) CALLOC_STRUCT(xmesa_context);
1651   if (!c)
1652      return NULL;
1653
1654   mesaCtx = &(c->mesa);
1655
1656   /* initialize with default driver functions, then plug in XMesa funcs */
1657   _mesa_init_driver_functions(&functions);
1658   xmesa_init_driver_functions(v, &functions);
1659   if (!_mesa_initialize_context(mesaCtx, &v->mesa_visual,
1660                      share_list ? &(share_list->mesa) : (GLcontext *) NULL,
1661                      &functions, (void *) c)) {
1662      FREE(c);
1663      return NULL;
1664   }
1665
1666   _mesa_enable_sw_extensions(mesaCtx);
1667   _mesa_enable_1_3_extensions(mesaCtx);
1668   _mesa_enable_1_4_extensions(mesaCtx);
1669   _mesa_enable_1_5_extensions(mesaCtx);
1670   _mesa_enable_2_0_extensions(mesaCtx);
1671#if SWTC
1672    if (c->Mesa_DXTn) {
1673       _mesa_enable_extension(c, "GL_EXT_texture_compression_s3tc");
1674       _mesa_enable_extension(c, "GL_S3_s3tc");
1675    }
1676    _mesa_enable_extension(c, "GL_3DFX_texture_compression_FXT1");
1677#endif
1678
1679   /* finish up xmesa context initializations */
1680   c->swapbytes = CHECK_BYTE_ORDER(v) ? GL_FALSE : GL_TRUE;
1681   c->xm_visual = v;
1682   c->xm_draw_buffer = NULL;   /* set later by XMesaMakeCurrent */
1683   c->xm_read_buffer = NULL;   /* set later by XMesaMakeCurrent */
1684   c->xm_buffer = NULL;   /* set later by XMesaMakeCurrent */
1685   c->display = v->display;
1686   c->pixelformat = v->dithered_pf;      /* Dithering is enabled by default */
1687
1688   /* Initialize the software rasterizer and helper modules.
1689    */
1690   if (!_swrast_CreateContext( mesaCtx ) ||
1691       !_ac_CreateContext( mesaCtx ) ||
1692       !_tnl_CreateContext( mesaCtx ) ||
1693       !_swsetup_CreateContext( mesaCtx )) {
1694      _mesa_free_context_data(&c->mesa);
1695      _mesa_free(c);
1696      return NULL;
1697   }
1698
1699   /* tnl setup */
1700   tnl = TNL_CONTEXT(mesaCtx);
1701   tnl->Driver.RunPipeline = _tnl_run_pipeline;
1702   /* swrast setup */
1703   xmesa_register_swrast_functions( mesaCtx );
1704   _swsetup_Wakeup(mesaCtx);
1705
1706   return c;
1707}
1708
1709
1710
1711void XMesaDestroyContext( XMesaContext c )
1712{
1713   GLcontext *mesaCtx = &c->mesa;
1714#ifdef FX
1715   if (c->xm_draw_buffer && c->xm_buffer->FXctx)
1716      fxMesaDestroyContext(c->xm_draw_buffer->FXctx);
1717#endif
1718   _swsetup_DestroyContext( mesaCtx );
1719   _swrast_DestroyContext( mesaCtx );
1720   _tnl_DestroyContext( mesaCtx );
1721   _ac_DestroyContext( mesaCtx );
1722   _mesa_free_context_data( mesaCtx );
1723   _mesa_free( c );
1724}
1725
1726
1727
1728/*
1729 * XXX this isn't a public function!  It's a hack for the 3Dfx driver.
1730 * Create a new XMesaBuffer from an X window.
1731 * Input:  v - the XMesaVisual
1732 *         w - the window
1733 *         c - the context
1734 * Return:  new XMesaBuffer or NULL if error
1735 */
1736XMesaBuffer XMesaCreateWindowBuffer2( XMesaVisual v, XMesaWindow w,
1737                                      XMesaContext c )
1738{
1739#ifndef XFree86Server
1740   XWindowAttributes attr;
1741#endif
1742#ifdef FX
1743   char *fxEnvVar;
1744#endif
1745   int client = 0;
1746
1747   XMesaBuffer b = alloc_xmesa_buffer();
1748   if (!b) {
1749      return NULL;
1750   }
1751
1752   (void) c;
1753
1754#ifdef XFree86Server
1755   client = CLIENT_ID(((XMesaDrawable)w)->id);
1756#endif
1757
1758   assert(v);
1759
1760#ifdef XFree86Server
1761   if (GET_VISUAL_DEPTH(v) != ((XMesaDrawable)w)->depth) {
1762#else
1763   XGetWindowAttributes( v->display, w, &attr );
1764
1765   if (GET_VISUAL_DEPTH(v) != attr.depth) {
1766#endif
1767      _mesa_warning(NULL, "XMesaCreateWindowBuffer: depth mismatch between visual and window!\n");
1768      return NULL;
1769   }
1770
1771   b->xm_visual = v;
1772   b->type = WINDOW;
1773   b->display = v->display;
1774#ifdef XFree86Server
1775   b->cmap = (ColormapPtr)LookupIDByType(wColormap(w), RT_COLORMAP);
1776#else
1777   if (attr.colormap) {
1778      b->cmap = attr.colormap;
1779   }
1780   else {
1781      _mesa_warning(NULL, "Window %u has no colormap!\n", (unsigned int) w);
1782      /* this is weird, a window w/out a colormap!? */
1783      /* OK, let's just allocate a new one and hope for the best */
1784      b->cmap = XCreateColormap(v->display, w, attr.visual, AllocNone);
1785   }
1786#endif
1787
1788   /* determine back buffer implementation */
1789   if (v->mesa_visual.doubleBufferMode) {
1790      if (v->ximage_flag) {
1791	 b->db_state = BACK_XIMAGE;
1792      }
1793      else {
1794	 b->db_state = BACK_PIXMAP;
1795      }
1796   }
1797   else {
1798      b->db_state = 0;
1799   }
1800
1801   _mesa_initialize_framebuffer(&b->mesa_buffer,
1802                                &v->mesa_visual,
1803                                v->mesa_visual.depthBits > 0,
1804                                v->mesa_visual.stencilBits > 0,
1805                                v->mesa_visual.accumRedBits > 0,
1806                                v->mesa_visual.alphaBits > 0 );
1807   /* XXX hack */
1808   b->mesa_buffer.UseSoftwareAuxBuffers = GL_TRUE;
1809
1810   if (!initialize_visual_and_buffer( client, v, b, v->mesa_visual.rgbMode,
1811                                      (XMesaDrawable)w, b->cmap )) {
1812      free_xmesa_buffer(client, b);
1813      return NULL;
1814   }
1815
1816#ifdef FX
1817   fxEnvVar = _mesa_getenv("MESA_GLX_FX");
1818   if (fxEnvVar) {
1819     if (fxEnvVar[0]!='d') {
1820       int attribs[100];
1821       int numAttribs = 0;
1822       int hw;
1823       if (v->mesa_visual.depthBits > 0) {
1824	 attribs[numAttribs++] = FXMESA_DEPTH_SIZE;
1825	 attribs[numAttribs++] = v->mesa_visual.depthBits;
1826       }
1827       if (v->mesa_visual.doubleBufferMode) {
1828	 attribs[numAttribs++] = FXMESA_DOUBLEBUFFER;
1829       }
1830       if (v->mesa_visual.accumRedBits > 0) {
1831	 attribs[numAttribs++] = FXMESA_ACCUM_SIZE;
1832	 attribs[numAttribs++] = v->mesa_visual.accumRedBits;
1833       }
1834       if (v->mesa_visual.stencilBits > 0) {
1835         attribs[numAttribs++] = FXMESA_STENCIL_SIZE;
1836         attribs[numAttribs++] = v->mesa_visual.stencilBits;
1837       }
1838       if (v->mesa_visual.alphaBits > 0) {
1839         attribs[numAttribs++] = FXMESA_ALPHA_SIZE;
1840         attribs[numAttribs++] = v->mesa_visual.alphaBits;
1841       }
1842       if (1) {
1843         attribs[numAttribs++] = FXMESA_SHARE_CONTEXT;
1844         attribs[numAttribs++] = (int) &(c->mesa);
1845       }
1846       attribs[numAttribs++] = FXMESA_NONE;
1847
1848       /* [dBorca] we should take an envvar for `fxMesaSelectCurrentBoard'!!! */
1849       hw = fxMesaSelectCurrentBoard(0);
1850       if ((hw == GR_SSTTYPE_VOODOO) || (hw == GR_SSTTYPE_Voodoo2)) {
1851         b->FXctx = fxMesaCreateBestContext(0, b->width, b->height, attribs);
1852         if ((v->undithered_pf!=PF_Index) && (b->backimage)) {
1853	   b->FXisHackUsable = b->FXctx ? GL_TRUE : GL_FALSE;
1854	   if (b->FXctx && (fxEnvVar[0]=='w' || fxEnvVar[0]=='W')) {
1855	     b->FXwindowHack = GL_TRUE;
1856	     FX_grSstControl(GR_CONTROL_DEACTIVATE);
1857	   }
1858           else {
1859	     b->FXwindowHack = GL_FALSE;
1860	   }
1861         }
1862       }
1863       else {
1864         if (fxEnvVar[0]=='w' || fxEnvVar[0]=='W')
1865	   b->FXctx = fxMesaCreateContext(w, GR_RESOLUTION_NONE,
1866					  GR_REFRESH_75Hz, attribs);
1867         else
1868	   b->FXctx = fxMesaCreateBestContext(0, b->width, b->height, attribs);
1869         b->FXisHackUsable = GL_FALSE;
1870         b->FXwindowHack = GL_FALSE;
1871       }
1872       /*
1873       fprintf(stderr,
1874               "voodoo %d, wid %d height %d hack: usable %d active %d\n",
1875               hw, b->width, b->height, b->FXisHackUsable, b->FXwindowHack);
1876       */
1877     }
1878   }
1879   else {
1880      _mesa_warning(NULL, "WARNING: This Mesa Library includes the Glide driver but\n");
1881      _mesa_warning(NULL, "         you have not defined the MESA_GLX_FX env. var.\n");
1882      _mesa_warning(NULL, "         (check the README.3DFX file for more information).\n\n");
1883      _mesa_warning(NULL, "         you can disable this message with a 'export MESA_GLX_FX=disable'.\n");
1884   }
1885#endif
1886
1887   return b;
1888}
1889
1890
1891XMesaBuffer XMesaCreateWindowBuffer( XMesaVisual v, XMesaWindow w )
1892{
1893   return XMesaCreateWindowBuffer2( v, w, NULL );
1894}
1895
1896
1897/**
1898 * Create a new XMesaBuffer from an X pixmap.
1899 *
1900 * \param v    the XMesaVisual
1901 * \param p    the pixmap
1902 * \param cmap the colormap, may be 0 if using a \c GLX_TRUE_COLOR or
1903 *             \c GLX_DIRECT_COLOR visual for the pixmap
1904 * \returns new XMesaBuffer or NULL if error
1905 */
1906XMesaBuffer XMesaCreatePixmapBuffer( XMesaVisual v,
1907				     XMesaPixmap p, XMesaColormap cmap )
1908{
1909   int client = 0;
1910   XMesaBuffer b = alloc_xmesa_buffer();
1911   if (!b) {
1912      return NULL;
1913   }
1914
1915
1916#ifdef XFree86Server
1917   client = CLIENT_ID(((XMesaDrawable)p)->id);
1918#endif
1919
1920   assert(v);
1921
1922   b->xm_visual = v;
1923   b->type = PIXMAP;
1924   b->display = v->display;
1925   b->cmap = cmap;
1926
1927   /* determine back buffer implementation */
1928   if (v->mesa_visual.doubleBufferMode) {
1929      if (v->ximage_flag) {
1930	 b->db_state = BACK_XIMAGE;
1931      }
1932      else {
1933	 b->db_state = BACK_PIXMAP;
1934      }
1935   }
1936   else {
1937      b->db_state = 0;
1938   }
1939
1940   _mesa_initialize_framebuffer(&b->mesa_buffer,
1941                                &v->mesa_visual,
1942                                v->mesa_visual.depthBits > 0,
1943                                v->mesa_visual.stencilBits > 0,
1944                                v->mesa_visual.accumRedBits +
1945                                v->mesa_visual.accumGreenBits +
1946                                v->mesa_visual.accumBlueBits > 0,
1947                                v->mesa_visual.alphaBits > 0 );
1948
1949   if (!initialize_visual_and_buffer(client, v, b, v->mesa_visual.rgbMode,
1950				     (XMesaDrawable)p, cmap)) {
1951      free_xmesa_buffer(client, b);
1952      return NULL;
1953   }
1954
1955   return b;
1956}
1957
1958
1959
1960XMesaBuffer XMesaCreatePBuffer( XMesaVisual v, XMesaColormap cmap,
1961                                unsigned int width, unsigned int height )
1962{
1963#ifdef XFree86Server
1964   return 0;
1965#else
1966   int client = 0;
1967   XMesaWindow root;
1968   XMesaDrawable drawable;  /* X Pixmap Drawable */
1969   XMesaBuffer b = alloc_xmesa_buffer();
1970   if (!b) {
1971      return NULL;
1972   }
1973
1974   b->xm_visual = v;
1975   b->type = PBUFFER;
1976   b->display = v->display;
1977   b->cmap = cmap;
1978
1979   /* allocate pixmap for front buffer */
1980   root = RootWindow( v->display, v->visinfo->screen );
1981   drawable = XCreatePixmap( v->display, root, width, height, v->visinfo->depth );
1982
1983   /* determine back buffer implementation */
1984   if (v->mesa_visual.doubleBufferMode) {
1985      if (v->ximage_flag) {
1986	 b->db_state = BACK_XIMAGE;
1987      }
1988      else {
1989	 b->db_state = BACK_PIXMAP;
1990      }
1991   }
1992   else {
1993      b->db_state = 0;
1994   }
1995
1996   _mesa_initialize_framebuffer(&b->mesa_buffer,
1997                                &v->mesa_visual,
1998                                v->mesa_visual.depthBits > 0,
1999                                v->mesa_visual.stencilBits > 0,
2000                                v->mesa_visual.accumRedBits +
2001                                v->mesa_visual.accumGreenBits +
2002                                v->mesa_visual.accumBlueBits > 0,
2003                                v->mesa_visual.alphaBits > 0 );
2004
2005   if (!initialize_visual_and_buffer(client, v, b, v->mesa_visual.rgbMode,
2006				     drawable, cmap)) {
2007      free_xmesa_buffer(client, b);
2008      return NULL;
2009   }
2010
2011   return b;
2012#endif
2013}
2014
2015
2016
2017/*
2018 * Deallocate an XMesaBuffer structure and all related info.
2019 */
2020void XMesaDestroyBuffer( XMesaBuffer b )
2021{
2022   int client = 0;
2023
2024#ifdef XFree86Server
2025   if (b->frontbuffer)
2026       client = CLIENT_ID(b->frontbuffer->id);
2027#endif
2028
2029   if (b->gc)  XMesaFreeGC( b->xm_visual->display, b->gc );
2030   if (b->cleargc)  XMesaFreeGC( b->xm_visual->display, b->cleargc );
2031   if (b->swapgc)  XMesaFreeGC( b->xm_visual->display, b->swapgc );
2032
2033   if (b->backimage) {
2034#if defined(USE_XSHM) && !defined(XFree86Server)
2035       if (b->shm) {
2036	   XShmDetach( b->xm_visual->display, &b->shminfo );
2037	   XDestroyImage( b->backimage );
2038	   shmdt( b->shminfo.shmaddr );
2039       }
2040       else
2041#endif
2042	   XMesaDestroyImage( b->backimage );
2043   }
2044   if (b->backpixmap) {
2045      XMesaFreePixmap( b->xm_visual->display, b->backpixmap );
2046      if (b->xm_visual->hpcr_clear_flag) {
2047	XMesaFreePixmap( b->xm_visual->display,
2048			 b->xm_visual->hpcr_clear_pixmap );
2049	XMesaDestroyImage( b->xm_visual->hpcr_clear_ximage );
2050      }
2051   }
2052   if (b->rowimage) {
2053      FREE( b->rowimage->data );
2054      b->rowimage->data = NULL;
2055      XMesaDestroyImage( b->rowimage );
2056   }
2057
2058   free_xmesa_buffer(client, b);
2059}
2060
2061
2062
2063/*
2064 * Bind buffer b to context c and make c the current rendering context.
2065 */
2066GLboolean XMesaMakeCurrent( XMesaContext c, XMesaBuffer b )
2067{
2068   return XMesaMakeCurrent2( c, b, b );
2069}
2070
2071
2072/*
2073 * Bind buffer b to context c and make c the current rendering context.
2074 */
2075GLboolean XMesaMakeCurrent2( XMesaContext c, XMesaBuffer drawBuffer,
2076                             XMesaBuffer readBuffer )
2077{
2078   if (c) {
2079      if (!drawBuffer || !readBuffer)
2080         return GL_FALSE;  /* must specify buffers! */
2081
2082#ifdef FX
2083      if (drawBuffer->FXctx) {
2084         fxMesaMakeCurrent(drawBuffer->FXctx);
2085
2086         c->xm_draw_buffer = drawBuffer;
2087         c->xm_read_buffer = readBuffer;
2088         c->xm_buffer = drawBuffer;
2089
2090         return GL_TRUE;
2091      }
2092#endif
2093      if (&(c->mesa) == _mesa_get_current_context()
2094          && c->xm_draw_buffer == drawBuffer
2095          && c->xm_read_buffer == readBuffer
2096          && c->xm_draw_buffer->wasCurrent) {
2097         /* same context and buffer, do nothing */
2098         return GL_TRUE;
2099      }
2100
2101      c->xm_draw_buffer = drawBuffer;
2102      c->xm_read_buffer = readBuffer;
2103      c->xm_buffer = drawBuffer;
2104
2105      _mesa_make_current2(&(c->mesa),
2106                          &drawBuffer->mesa_buffer,
2107                          &readBuffer->mesa_buffer);
2108
2109      if (c->mesa.Viewport.Width == 0) {
2110	 /* initialize viewport to window size */
2111	 _mesa_Viewport( 0, 0, drawBuffer->width, drawBuffer->height );
2112	 c->mesa.Scissor.Width = drawBuffer->width;
2113	 c->mesa.Scissor.Height = drawBuffer->height;
2114      }
2115
2116      if (c->xm_visual->mesa_visual.rgbMode) {
2117         /*
2118          * Must recompute and set these pixel values because colormap
2119          * can be different for different windows.
2120          */
2121         c->clearpixel = xmesa_color_to_pixel( c,
2122                                               c->clearcolor[0],
2123                                               c->clearcolor[1],
2124                                               c->clearcolor[2],
2125                                               c->clearcolor[3],
2126                                               c->xm_visual->undithered_pf);
2127         XMesaSetForeground(c->display, c->xm_draw_buffer->cleargc, c->clearpixel);
2128      }
2129
2130      /* Solution to Stephane Rehel's problem with glXReleaseBuffersMESA(): */
2131      c->xm_draw_buffer->wasCurrent = GL_TRUE;
2132   }
2133   else {
2134      /* Detach */
2135      _mesa_make_current2( NULL, NULL, NULL );
2136   }
2137   return GL_TRUE;
2138}
2139
2140
2141/*
2142 * Unbind the context c from its buffer.
2143 */
2144GLboolean XMesaUnbindContext( XMesaContext c )
2145{
2146   /* A no-op for XFree86 integration purposes */
2147   return GL_TRUE;
2148}
2149
2150
2151XMesaContext XMesaGetCurrentContext( void )
2152{
2153   GET_CURRENT_CONTEXT(ctx);
2154   if (ctx) {
2155      XMesaContext xmesa = XMESA_CONTEXT(ctx);
2156      return xmesa;
2157   }
2158   else {
2159      return 0;
2160   }
2161}
2162
2163
2164XMesaBuffer XMesaGetCurrentBuffer( void )
2165{
2166   GET_CURRENT_CONTEXT(ctx);
2167   if (ctx) {
2168      XMesaContext xmesa = XMESA_CONTEXT(ctx);
2169      return xmesa->xm_draw_buffer;
2170   }
2171   else {
2172      return 0;
2173   }
2174}
2175
2176
2177/* New in Mesa 3.1 */
2178XMesaBuffer XMesaGetCurrentReadBuffer( void )
2179{
2180   GET_CURRENT_CONTEXT(ctx);
2181   if (ctx) {
2182      XMesaContext xmesa = XMESA_CONTEXT(ctx);
2183      return xmesa->xm_read_buffer;
2184   }
2185   else {
2186      return 0;
2187   }
2188}
2189
2190
2191GLboolean XMesaForceCurrent(XMesaContext c)
2192{
2193   if (c) {
2194      if (&(c->mesa) != _mesa_get_current_context()) {
2195	 _mesa_make_current(&(c->mesa), &c->xm_draw_buffer->mesa_buffer);
2196      }
2197   }
2198   else {
2199      _mesa_make_current(NULL, NULL);
2200   }
2201   return GL_TRUE;
2202}
2203
2204
2205GLboolean XMesaLoseCurrent(XMesaContext c)
2206{
2207   (void) c;
2208   _mesa_make_current(NULL, NULL);
2209   return GL_TRUE;
2210}
2211
2212
2213/*
2214 * Switch 3Dfx support hack between window and full-screen mode.
2215 */
2216GLboolean XMesaSetFXmode( GLint mode )
2217{
2218#ifdef FX
2219   const char *fx = _mesa_getenv("MESA_GLX_FX");
2220   if (fx && fx[0] != 'd') {
2221      GET_CURRENT_CONTEXT(ctx);
2222      GrHwConfiguration hw;
2223      if (!FX_grSstQueryHardware(&hw)) {
2224         /*fprintf(stderr, "!grSstQueryHardware\n");*/
2225         return GL_FALSE;
2226      }
2227      if (hw.num_sst < 1) {
2228         /*fprintf(stderr, "hw.num_sst < 1\n");*/
2229         return GL_FALSE;
2230      }
2231      if (ctx) {
2232         /* [dBorca] Hack alert:
2233	  * oh, this is sooo wrong: ctx above is
2234	  * really an fxMesaContext, not an XMesaContext
2235	  */
2236         XMesaContext xmesa = XMESA_CONTEXT(ctx);
2237         if (mode == XMESA_FX_WINDOW) {
2238	    if (xmesa->xm_draw_buffer->FXisHackUsable) {
2239	       FX_grSstControl(GR_CONTROL_DEACTIVATE);
2240	       xmesa->xm_draw_buffer->FXwindowHack = GL_TRUE;
2241	       return GL_TRUE;
2242	    }
2243	 }
2244	 else if (mode == XMESA_FX_FULLSCREEN) {
2245	    FX_grSstControl(GR_CONTROL_ACTIVATE);
2246	    xmesa->xm_draw_buffer->FXwindowHack = GL_FALSE;
2247	    return GL_TRUE;
2248	 }
2249	 else {
2250	    /* Error: Bad mode value */
2251	 }
2252      }
2253   }
2254   /*fprintf(stderr, "fallthrough\n");*/
2255#else
2256   (void) mode;
2257#endif
2258   return GL_FALSE;
2259}
2260
2261
2262
2263#ifdef FX
2264/*
2265 * Read image from VooDoo frame buffer into X/Mesa's back XImage.
2266 */
2267static void FXgetImage( XMesaBuffer b )
2268{
2269   GET_CURRENT_CONTEXT(ctx);
2270   static unsigned short pixbuf[MAX_WIDTH];
2271   GLuint x, y;
2272   int xpos, ypos;
2273   XMesaWindow root;
2274   unsigned int bw, depth, width, height;
2275   XMesaContext xmesa = XMESA_CONTEXT(ctx);
2276
2277#ifdef XFree86Server
2278   x = b->frontbuffer->x;
2279   y = b->frontbuffer->y;
2280   width = b->frontbuffer->width;
2281   height = b->frontbuffer->height;
2282   depth = b->frontbuffer->depth;
2283#else
2284   XGetGeometry( b->xm_visual->display, b->frontbuffer,
2285                 &root, &xpos, &ypos, &width, &height, &bw, &depth);
2286#endif
2287   if (b->width != width || b->height != height) {
2288      b->width = MIN2((int)width, b->FXctx->width);
2289      b->height = MIN2((int)height, b->FXctx->height);
2290      if (b->width & 1)
2291         b->width--;  /* prevent odd width */
2292      xmesa_alloc_back_buffer( b );
2293   }
2294
2295   /* [dBorca] we're always in the right GR_COLORFORMAT... aren't we? */
2296   /* grLfbWriteColorFormat(GR_COLORFORMAT_ARGB); */
2297   if (b->xm_visual->undithered_pf==PF_5R6G5B) {
2298      /* Special case: 16bpp RGB */
2299      grLfbReadRegion( GR_BUFFER_FRONTBUFFER,       /* src buffer */
2300                       0, b->FXctx->height - b->height,  /*pos*/
2301                       b->width, b->height,         /* size */
2302                       b->width * sizeof(GLushort), /* stride */
2303                       b->backimage->data);         /* dest buffer */
2304   }
2305   else if (b->xm_visual->dithered_pf==PF_Dither
2306	    && GET_VISUAL_DEPTH(b->xm_visual)==8) {
2307      /* Special case: 8bpp RGB */
2308      for (y=0;y<b->height;y++) {
2309         GLubyte *ptr = (GLubyte*) b->backimage->data
2310                        + b->backimage->bytes_per_line * y;
2311         XDITHER_SETUP(y);
2312
2313         /* read row from 3Dfx frame buffer */
2314         grLfbReadRegion( GR_BUFFER_FRONTBUFFER,
2315                          0, b->FXctx->height-(b->height-y),
2316                          b->width, 1,
2317                          0,
2318                          pixbuf );
2319
2320         /* write to XImage back buffer */
2321         for (x=0;x<b->width;x++) {
2322            GLubyte r = (pixbuf[x] & 0xf800) >> 8;
2323            GLubyte g = (pixbuf[x] & 0x07e0) >> 3;
2324            GLubyte b = (pixbuf[x] & 0x001f) << 3;
2325            *ptr++ = XDITHER( x, r, g, b);
2326         }
2327      }
2328   }
2329   else {
2330      /* General case: slow! */
2331      for (y=0;y<b->height;y++) {
2332         /* read row from 3Dfx frame buffer */
2333         grLfbReadRegion( GR_BUFFER_FRONTBUFFER,
2334                          0, b->FXctx->height-(b->height-y),
2335                          b->width, 1,
2336                          0,
2337                          pixbuf );
2338
2339         /* write to XImage back buffer */
2340         for (x=0;x<b->width;x++) {
2341            XMesaPutPixel(b->backimage,x,y,
2342			  xmesa_color_to_pixel(xmesa,
2343					       (pixbuf[x] & 0xf800) >> 8,
2344					       (pixbuf[x] & 0x07e0) >> 3,
2345					       (pixbuf[x] & 0x001f) << 3,
2346					       0xff,
2347                                               b->xm_visual->undithered_pf));
2348         }
2349      }
2350   }
2351   /* grLfbWriteColorFormat(GR_COLORFORMAT_ABGR); */
2352}
2353#endif
2354
2355
2356/*
2357 * Copy the back buffer to the front buffer.  If there's no back buffer
2358 * this is a no-op.
2359 */
2360void XMesaSwapBuffers( XMesaBuffer b )
2361{
2362   GET_CURRENT_CONTEXT(ctx);
2363
2364   /* If we're swapping the buffer associated with the current context
2365    * we have to flush any pending rendering commands first.
2366    */
2367   if (ctx && ctx->DrawBuffer == &(b->mesa_buffer))
2368      _mesa_notifySwapBuffers(ctx);
2369
2370   if (b->db_state) {
2371#ifdef FX
2372      if (b->FXctx) {
2373         fxMesaSwapBuffers();
2374
2375         if (b->FXwindowHack)
2376            FXgetImage(b);
2377         else
2378            return;
2379      }
2380#endif
2381     if (b->backimage) {
2382	 /* Copy Ximage from host's memory to server's window */
2383#if defined(USE_XSHM) && !defined(XFree86Server)
2384	 if (b->shm) {
2385            /*_glthread_LOCK_MUTEX(_xmesa_lock);*/
2386	    XShmPutImage( b->xm_visual->display, b->frontbuffer,
2387			  b->swapgc,
2388			  b->backimage, 0, 0,
2389			  0, 0, b->width, b->height, False );
2390            /*_glthread_UNLOCK_MUTEX(_xmesa_lock);*/
2391	 }
2392	 else
2393#endif
2394         {
2395            /*_glthread_LOCK_MUTEX(_xmesa_lock);*/
2396            XMesaPutImage( b->xm_visual->display, b->frontbuffer,
2397			   b->swapgc,
2398			   b->backimage, 0, 0,
2399			   0, 0, b->width, b->height );
2400            /*_glthread_UNLOCK_MUTEX(_xmesa_lock);*/
2401         }
2402      }
2403      else {
2404	 /* Copy pixmap to window on server */
2405         /*_glthread_LOCK_MUTEX(_xmesa_lock);*/
2406	 XMesaCopyArea( b->xm_visual->display,
2407			b->backpixmap,   /* source drawable */
2408			b->frontbuffer,  /* dest. drawable */
2409			b->swapgc,
2410			0, 0, b->width, b->height,  /* source region */
2411			0, 0                 /* dest region */
2412		      );
2413         /*_glthread_UNLOCK_MUTEX(_xmesa_lock);*/
2414      }
2415   }
2416#if !defined(XFree86Server)
2417   XSync( b->xm_visual->display, False );
2418#endif
2419}
2420
2421
2422
2423/*
2424 * Copy sub-region of back buffer to front buffer
2425 */
2426void XMesaCopySubBuffer( XMesaBuffer b, int x, int y, int width, int height )
2427{
2428   GET_CURRENT_CONTEXT(ctx);
2429
2430   /* If we're swapping the buffer associated with the current context
2431    * we have to flush any pending rendering commands first.
2432    */
2433   if (ctx && ctx->DrawBuffer == &(b->mesa_buffer))
2434      _mesa_notifySwapBuffers(ctx);
2435
2436   if (b->db_state) {
2437      int yTop = b->height - y - height;
2438#ifdef FX
2439      if (b->FXctx) {
2440         fxMesaSwapBuffers();
2441         if (b->FXwindowHack)
2442            FXgetImage(b);
2443         else
2444            return;
2445      }
2446#endif
2447      if (b->backimage) {
2448         /* Copy Ximage from host's memory to server's window */
2449#if defined(USE_XSHM) && !defined(XFree86Server)
2450         if (b->shm) {
2451            /* XXX assuming width and height aren't too large! */
2452            XShmPutImage( b->xm_visual->display, b->frontbuffer,
2453                          b->swapgc,
2454                          b->backimage, x, yTop,
2455                          x, yTop, width, height, False );
2456            /* wait for finished event??? */
2457         }
2458         else
2459#endif
2460         {
2461            /* XXX assuming width and height aren't too large! */
2462            XMesaPutImage( b->xm_visual->display, b->frontbuffer,
2463			   b->swapgc,
2464			   b->backimage, x, yTop,
2465			   x, yTop, width, height );
2466         }
2467      }
2468      else {
2469         /* Copy pixmap to window on server */
2470         XMesaCopyArea( b->xm_visual->display,
2471			b->backpixmap,           /* source drawable */
2472			b->frontbuffer,          /* dest. drawable */
2473			b->swapgc,
2474			x, yTop, width, height,  /* source region */
2475			x, yTop                  /* dest region */
2476                      );
2477      }
2478   }
2479}
2480
2481
2482/*
2483 * Return a pointer to the XMesa backbuffer Pixmap or XImage.  This function
2484 * is a way to get "under the hood" of X/Mesa so one can manipulate the
2485 * back buffer directly.
2486 * Output:  pixmap - pointer to back buffer's Pixmap, or 0
2487 *          ximage - pointer to back buffer's XImage, or NULL
2488 * Return:  GL_TRUE = context is double buffered
2489 *          GL_FALSE = context is single buffered
2490 */
2491GLboolean XMesaGetBackBuffer( XMesaBuffer b,
2492                              XMesaPixmap *pixmap,
2493                              XMesaImage **ximage )
2494{
2495   if (b->db_state) {
2496      if (pixmap)  *pixmap = b->backpixmap;
2497      if (ximage)  *ximage = b->backimage;
2498      return GL_TRUE;
2499   }
2500   else {
2501      *pixmap = 0;
2502      *ximage = NULL;
2503      return GL_FALSE;
2504   }
2505}
2506
2507
2508/*
2509 * Return the depth buffer associated with an XMesaBuffer.
2510 * Input:  b - the XMesa buffer handle
2511 * Output:  width, height - size of buffer in pixels
2512 *          bytesPerValue - bytes per depth value (2 or 4)
2513 *          buffer - pointer to depth buffer values
2514 * Return:  GL_TRUE or GL_FALSE to indicate success or failure.
2515 */
2516GLboolean XMesaGetDepthBuffer( XMesaBuffer b, GLint *width, GLint *height,
2517                               GLint *bytesPerValue, void **buffer )
2518{
2519   if (!b->mesa_buffer.DepthBuffer) {
2520      *width = 0;
2521      *height = 0;
2522      *bytesPerValue = 0;
2523      *buffer = 0;
2524      return GL_FALSE;
2525   }
2526   else {
2527      *width = b->mesa_buffer.Width;
2528      *height = b->mesa_buffer.Height;
2529      *bytesPerValue = sizeof(GLdepth);
2530      *buffer = b->mesa_buffer.DepthBuffer;
2531      return GL_TRUE;
2532   }
2533}
2534
2535
2536void XMesaFlush( XMesaContext c )
2537{
2538   if (c && c->xm_visual) {
2539#ifdef XFree86Server
2540      /* NOT_NEEDED */
2541#else
2542      XSync( c->xm_visual->display, False );
2543#endif
2544   }
2545}
2546
2547
2548
2549const char *XMesaGetString( XMesaContext c, int name )
2550{
2551   (void) c;
2552   if (name==XMESA_VERSION) {
2553      return "5.0";
2554   }
2555   else if (name==XMESA_EXTENSIONS) {
2556      return "";
2557   }
2558   else {
2559      return NULL;
2560   }
2561}
2562
2563
2564
2565XMesaBuffer XMesaFindBuffer( XMesaDisplay *dpy, XMesaDrawable d )
2566{
2567   XMesaBuffer b;
2568   for (b=XMesaBufferList; b; b=b->Next) {
2569      if (b->frontbuffer==d && b->display==dpy) {
2570         return b;
2571      }
2572   }
2573   return NULL;
2574}
2575
2576
2577
2578/*
2579 * Look for XMesaBuffers whose X window has been destroyed.
2580 * Deallocate any such XMesaBuffers.
2581 */
2582void XMesaGarbageCollect( void )
2583{
2584   XMesaBuffer b, next;
2585   for (b=XMesaBufferList; b; b=next) {
2586      next = b->Next;
2587      if (b->display && b->frontbuffer && b->type == WINDOW) {
2588#ifdef XFree86Server
2589	 /* NOT_NEEDED */
2590#else
2591         XSync(b->display, False);
2592         if (!window_exists( b->display, b->frontbuffer )) {
2593            /* found a dead window, free the ancillary info */
2594            XMesaDestroyBuffer( b );
2595         }
2596#endif
2597      }
2598   }
2599}
2600
2601
2602void XMesaReset( void )
2603{
2604    while (XMesaBufferList)
2605	XMesaDestroyBuffer(XMesaBufferList);
2606
2607    XMesaBufferList = NULL;
2608}
2609
2610
2611unsigned long XMesaDitherColor( XMesaContext xmesa, GLint x, GLint y,
2612                                GLfloat red, GLfloat green,
2613                                GLfloat blue, GLfloat alpha )
2614{
2615   GLint r = (GLint) (red   * 255.0F);
2616   GLint g = (GLint) (green * 255.0F);
2617   GLint b = (GLint) (blue  * 255.0F);
2618   GLint a = (GLint) (alpha * 255.0F);
2619
2620   switch (xmesa->pixelformat) {
2621      case PF_Index:
2622         return 0;
2623      case PF_Truecolor:
2624         {
2625            unsigned long p;
2626            PACK_TRUECOLOR( p, r, g, b );
2627            return p;
2628         }
2629      case PF_8A8B8G8R:
2630         return PACK_8A8B8G8R( r, g, b, a );
2631      case PF_8R8G8B:
2632         return PACK_8R8G8B( r, g, b );
2633      case PF_5R6G5B:
2634         return PACK_5R6G5B( r, g, b );
2635      case PF_Dither:
2636         {
2637            DITHER_SETUP;
2638            return DITHER( x, y, r, g, b );
2639         }
2640      case PF_1Bit:
2641         /* 382 = (3*255)/2 */
2642         return ((r+g+b) > 382) ^ xmesa->xm_visual->bitFlip;
2643      case PF_HPCR:
2644         return DITHER_HPCR(x, y, r, g, b);
2645      case PF_Lookup:
2646         {
2647            LOOKUP_SETUP;
2648            return LOOKUP( r, g, b );
2649         }
2650      case PF_Grayscale:
2651         return GRAY_RGB( r, g, b );
2652      case PF_Dither_5R6G5B:
2653         /* fall through */
2654      case PF_Dither_True:
2655         {
2656            unsigned long p;
2657            PACK_TRUEDITHER(p, x, y, r, g, b);
2658            return p;
2659         }
2660      default:
2661         _mesa_problem(NULL, "Bad pixel format in XMesaDitherColor");
2662   }
2663   return 0;
2664}
2665
2666
2667/*
2668 * This is typically called when the window size changes and we need
2669 * to reallocate the buffer's back/depth/stencil/accum buffers.
2670 */
2671void XMesaResizeBuffers( XMesaBuffer b )
2672{
2673   xmesa_resize_buffers( &(b->mesa_buffer) );
2674
2675}
2676
2677