xm_api.c revision 3049946fa742b654afa9b24f8bc79f387f01aea9 
1/*
2 * Mesa 3-D graphics library
3 * Version:  6.5.2
4 *
5 * Copyright (C) 1999-2006  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 * \file xm_api.c
27 *
28 * All the XMesa* API functions.
29 *
30 *
31 * NOTES:
32 *
33 * The window coordinate system origin (0,0) is in the lower-left corner
34 * of the window.  X11's window coordinate origin is in the upper-left
35 * corner of the window.  Therefore, most drawing functions in this
36 * file have to flip Y coordinates.
37 *
38 * Define USE_XSHM in the Makefile with -DUSE_XSHM if you want to compile
39 * in support for the MIT Shared Memory extension.  If enabled, when you
40 * use an Ximage for the back buffer in double buffered mode, the "swap"
41 * operation will be faster.  You must also link with -lXext.
42 *
43 * Byte swapping:  If the Mesa host and the X display use a different
44 * byte order then there's some trickiness to be aware of when using
45 * XImages.  The byte ordering used for the XImage is that of the X
46 * display, not the Mesa host.
47 * The color-to-pixel encoding for True/DirectColor must be done
48 * according to the display's visual red_mask, green_mask, and blue_mask.
49 * If XPutPixel is used to put a pixel into an XImage then XPutPixel will
50 * do byte swapping if needed.  If one wants to directly "poke" the pixel
51 * into the XImage's buffer then the pixel must be byte swapped first.  In
52 * Mesa, when byte swapping is needed we use the PF_TRUECOLOR pixel format
53 * and use XPutPixel everywhere except in the implementation of
54 * glClear(GL_COLOR_BUFFER_BIT).  We want this function to be fast so
55 * instead of using XPutPixel we "poke" our values after byte-swapping
56 * the clear pixel value if needed.
57 *
58 */
59
60#ifdef __CYGWIN__
61#undef WIN32
62#undef __WIN32__
63#endif
64
65#include "glxheader.h"
66#include "GL/xmesa.h"
67#include "xmesaP.h"
68#include "context.h"
69#include "extensions.h"
70#include "framebuffer.h"
71#include "glthread.h"
72#include "imports.h"
73#include "macros.h"
74#include "renderbuffer.h"
75#include "swrast/swrast.h"
76#include "swrast_setup/swrast_setup.h"
77#include "vbo/vbo.h"
78#include "tnl/tnl.h"
79#include "tnl/t_context.h"
80#include "tnl/t_pipeline.h"
81#include "drivers/common/driverfuncs.h"
82
83#ifdef XFree86Server
84#include <GL/glxtokens.h>
85#endif
86
87/**
88 * Global X driver lock
89 */
90_glthread_Mutex _xmesa_lock;
91
92
93
94/**
95 * Lookup tables for HPCR pixel format:
96 */
97static short hpcr_rgbTbl[3][256] = {
98{
99 16,  16,  17,  17,  18,  18,  19,  19,  20,  20,  21,  21,  22,  22,  23,  23,
100 24,  24,  25,  25,  26,  26,  27,  27,  28,  28,  29,  29,  30,  30,  31,  31,
101 32,  32,  33,  33,  34,  34,  35,  35,  36,  36,  37,  37,  38,  38,  39,  39,
102 32,  33,  34,  35,  36,  37,  38,  39,  40,  41,  42,  43,  44,  45,  46,  47,
103 48,  49,  50,  51,  52,  53,  54,  55,  56,  57,  58,  59,  60,  61,  62,  63,
104 64,  65,  66,  67,  68,  69,  70,  71,  72,  73,  74,  75,  76,  77,  78,  79,
105 80,  81,  82,  83,  84,  85,  86,  87,  88,  89,  90,  91,  92,  93,  94,  95,
106 96,  97,  98,  99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111,
107112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127,
108128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143,
109144, 145, 146, 147, 148, 149, 150, 151, 152, 153, 154, 155, 156, 157, 158, 159,
110160, 161, 162, 163, 164, 165, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175,
111176, 177, 178, 179, 180, 181, 182, 183, 184, 185, 186, 187, 188, 189, 190, 191,
112192, 193, 194, 195, 196, 197, 198, 199, 200, 201, 202, 203, 204, 205, 206, 207,
113208, 209, 210, 211, 212, 213, 214, 215, 216, 217, 218, 219, 220, 221, 222, 223,
114224, 225, 226, 227, 228, 229, 230, 231, 232, 233, 234, 235, 236, 237, 238, 239
115},
116{
117 16,  16,  17,  17,  18,  18,  19,  19,  20,  20,  21,  21,  22,  22,  23,  23,
118 24,  24,  25,  25,  26,  26,  27,  27,  28,  28,  29,  29,  30,  30,  31,  31,
119 32,  32,  33,  33,  34,  34,  35,  35,  36,  36,  37,  37,  38,  38,  39,  39,
120 32,  33,  34,  35,  36,  37,  38,  39,  40,  41,  42,  43,  44,  45,  46,  47,
121 48,  49,  50,  51,  52,  53,  54,  55,  56,  57,  58,  59,  60,  61,  62,  63,
122 64,  65,  66,  67,  68,  69,  70,  71,  72,  73,  74,  75,  76,  77,  78,  79,
123 80,  81,  82,  83,  84,  85,  86,  87,  88,  89,  90,  91,  92,  93,  94,  95,
124 96,  97,  98,  99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111,
125112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127,
126128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143,
127144, 145, 146, 147, 148, 149, 150, 151, 152, 153, 154, 155, 156, 157, 158, 159,
128160, 161, 162, 163, 164, 165, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175,
129176, 177, 178, 179, 180, 181, 182, 183, 184, 185, 186, 187, 188, 189, 190, 191,
130192, 193, 194, 195, 196, 197, 198, 199, 200, 201, 202, 203, 204, 205, 206, 207,
131208, 209, 210, 211, 212, 213, 214, 215, 216, 217, 218, 219, 220, 221, 222, 223,
132224, 225, 226, 227, 228, 229, 230, 231, 232, 233, 234, 235, 236, 237, 238, 239
133},
134{
135 32,  32,  33,  33,  34,  34,  35,  35,  36,  36,  37,  37,  38,  38,  39,  39,
136 40,  40,  41,  41,  42,  42,  43,  43,  44,  44,  45,  45,  46,  46,  47,  47,
137 48,  48,  49,  49,  50,  50,  51,  51,  52,  52,  53,  53,  54,  54,  55,  55,
138 56,  56,  57,  57,  58,  58,  59,  59,  60,  60,  61,  61,  62,  62,  63,  63,
139 64,  64,  65,  65,  66,  66,  67,  67,  68,  68,  69,  69,  70,  70,  71,  71,
140 72,  72,  73,  73,  74,  74,  75,  75,  76,  76,  77,  77,  78,  78,  79,  79,
141 80,  80,  81,  81,  82,  82,  83,  83,  84,  84,  85,  85,  86,  86,  87,  87,
142 80,  81,  82,  83,  84,  85,  86,  87,  88,  89,  90,  91,  92,  93,  94,  95,
143 96,  97,  98,  99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111,
144112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127,
145128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143,
146144, 145, 146, 147, 148, 149, 150, 151, 152, 153, 154, 155, 156, 157, 158, 159,
147160, 161, 162, 163, 164, 165, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175,
148176, 177, 178, 179, 180, 181, 182, 183, 184, 185, 186, 187, 188, 189, 190, 191,
149192, 193, 194, 195, 196, 197, 198, 199, 200, 201, 202, 203, 204, 205, 206, 207,
150208, 209, 210, 211, 212, 213, 214, 215, 216, 217, 218, 219, 220, 221, 222, 223
151}
152};
153
154
155
156/**********************************************************************/
157/*****                     X Utility Functions                    *****/
158/**********************************************************************/
159
160
161/**
162 * Return the host's byte order as LSBFirst or MSBFirst ala X.
163 */
164#ifndef XFree86Server
165static int host_byte_order( void )
166{
167   int i = 1;
168   char *cptr = (char *) &i;
169   return (*cptr==1) ? LSBFirst : MSBFirst;
170}
171#endif
172
173
174/**
175 * Check if the X Shared Memory extension is available.
176 * Return:  0 = not available
177 *          1 = shared XImage support available
178 *          2 = shared Pixmap support available also
179 */
180static int check_for_xshm( XMesaDisplay *display )
181{
182#if defined(XFree86Server)
183   return 0;
184#elif defined(USE_XSHM)
185   int major, minor, ignore;
186   Bool pixmaps;
187
188   if (XQueryExtension( display, "MIT-SHM", &ignore, &ignore, &ignore )) {
189      if (XShmQueryVersion( display, &major, &minor, &pixmaps )==True) {
190	 return (pixmaps==True) ? 2 : 1;
191      }
192      else {
193	 return 0;
194      }
195   }
196   else {
197      return 0;
198   }
199#else
200   /* No  XSHM support */
201   return 0;
202#endif
203}
204
205
206/**
207 * Apply gamma correction to an intensity value in [0..max].  Return the
208 * new intensity value.
209 */
210static GLint
211gamma_adjust( GLfloat gamma, GLint value, GLint max )
212{
213   if (gamma == 1.0) {
214      return value;
215   }
216   else {
217      double x = (double) value / (double) max;
218      return IROUND_POS((GLfloat) max * _mesa_pow(x, 1.0F/gamma));
219   }
220}
221
222
223
224/**
225 * Return the true number of bits per pixel for XImages.
226 * For example, if we request a 24-bit deep visual we may actually need/get
227 * 32bpp XImages.  This function returns the appropriate bpp.
228 * Input:  dpy - the X display
229 *         visinfo - desribes the visual to be used for XImages
230 * Return:  true number of bits per pixel for XImages
231 */
232static int
233bits_per_pixel( XMesaVisual xmv )
234{
235#ifdef XFree86Server
236   const int depth = xmv->nplanes;
237   int i;
238   assert(depth > 0);
239   for (i = 0; i < screenInfo.numPixmapFormats; i++) {
240      if (screenInfo.formats[i].depth == depth)
241         return screenInfo.formats[i].bitsPerPixel;
242   }
243   return depth;  /* should never get here, but this should be safe */
244#else
245   XMesaDisplay *dpy = xmv->display;
246   XMesaVisualInfo visinfo = xmv->visinfo;
247   XMesaImage *img;
248   int bitsPerPixel;
249   /* Create a temporary XImage */
250   img = XCreateImage( dpy, visinfo->visual, visinfo->depth,
251		       ZPixmap, 0,           /*format, offset*/
252		       (char*) MALLOC(8),    /*data*/
253		       1, 1,                 /*width, height*/
254		       32,                   /*bitmap_pad*/
255		       0                     /*bytes_per_line*/
256                     );
257   assert(img);
258   /* grab the bits/pixel value */
259   bitsPerPixel = img->bits_per_pixel;
260   /* free the XImage */
261   _mesa_free( img->data );
262   img->data = NULL;
263   XMesaDestroyImage( img );
264   return bitsPerPixel;
265#endif
266}
267
268
269
270/*
271 * Determine if a given X window ID is valid (window exists).
272 * Do this by calling XGetWindowAttributes() for the window and
273 * checking if we catch an X error.
274 * Input:  dpy - the display
275 *         win - the window to check for existance
276 * Return:  GL_TRUE - window exists
277 *          GL_FALSE - window doesn't exist
278 */
279#ifndef XFree86Server
280static GLboolean WindowExistsFlag;
281
282static int window_exists_err_handler( XMesaDisplay* dpy, XErrorEvent* xerr )
283{
284   (void) dpy;
285   if (xerr->error_code == BadWindow) {
286      WindowExistsFlag = GL_FALSE;
287   }
288   return 0;
289}
290
291static GLboolean window_exists( XMesaDisplay *dpy, Window win )
292{
293   XWindowAttributes wa;
294   int (*old_handler)( XMesaDisplay*, XErrorEvent* );
295   WindowExistsFlag = GL_TRUE;
296   old_handler = XSetErrorHandler(window_exists_err_handler);
297   XGetWindowAttributes( dpy, win, &wa ); /* dummy request */
298   XSetErrorHandler(old_handler);
299   return WindowExistsFlag;
300}
301#endif
302
303
304
305/**
306 * Return the size of the window (or pixmap) that corresponds to the
307 * given XMesaBuffer.
308 * \param width  returns width in pixels
309 * \param height  returns height in pixels
310 */
311void
312xmesa_get_window_size(XMesaDisplay *dpy, XMesaBuffer b,
313                      GLuint *width, GLuint *height)
314{
315#ifdef XFree86Server
316   *width = MIN2(b->frontxrb->drawable->width, MAX_WIDTH);
317   *height = MIN2(b->frontxrb->drawable->height, MAX_HEIGHT);
318#else
319   Window root;
320   Status stat;
321   int xpos, ypos;
322   unsigned int w, h, bw, depth;
323
324   _glthread_LOCK_MUTEX(_xmesa_lock);
325   XSync(b->xm_visual->display, 0); /* added for Chromium */
326   stat = XGetGeometry(dpy, b->frontxrb->pixmap, &root, &xpos, &ypos,
327                       &w, &h, &bw, &depth);
328   _glthread_UNLOCK_MUTEX(_xmesa_lock);
329
330   if (stat) {
331      *width = w;
332      *height = h;
333   }
334   else {
335      /* probably querying a window that's recently been destroyed */
336      _mesa_warning(NULL, "XGetGeometry failed!\n");
337      *width = *height = 1;
338   }
339#endif
340}
341
342
343
344/**********************************************************************/
345/*****                Linked list of XMesaBuffers                 *****/
346/**********************************************************************/
347
348XMesaBuffer XMesaBufferList = NULL;
349
350
351/**
352 * Allocate a new XMesaBuffer object which corresponds to the given drawable.
353 * Note that XMesaBuffer is derived from GLframebuffer.
354 * The new XMesaBuffer will not have any size (Width=Height=0).
355 *
356 * \param d  the corresponding X drawable (window or pixmap)
357 * \param type  either WINDOW, PIXMAP or PBUFFER, describing d
358 * \param vis  the buffer's visual
359 * \param cmap  the window's colormap, if known.
360 * \return new XMesaBuffer or NULL if any problem
361 */
362static XMesaBuffer
363create_xmesa_buffer(XMesaDrawable d, BufferType type,
364                    XMesaVisual vis, XMesaColormap cmap)
365{
366   GLboolean swAlpha;
367   XMesaBuffer b;
368
369   ASSERT(type == WINDOW || type == PIXMAP || type == PBUFFER);
370
371   b = (XMesaBuffer) CALLOC_STRUCT(xmesa_buffer);
372   if (!b)
373      return NULL;
374
375   b->display = vis->display;
376   b->xm_visual = vis;
377   b->type = type;
378   b->cmap = cmap;
379
380   _mesa_initialize_framebuffer(&b->mesa_buffer, &vis->mesa_visual);
381   b->mesa_buffer.Delete = xmesa_delete_framebuffer;
382
383   /*
384    * Front renderbuffer
385    */
386   b->frontxrb = xmesa_new_renderbuffer(NULL, 0, &vis->mesa_visual, GL_FALSE);
387   if (!b->frontxrb) {
388      _mesa_free(b);
389      return NULL;
390   }
391   b->frontxrb->Parent = b;
392   b->frontxrb->drawable = d;
393   b->frontxrb->pixmap = (XMesaPixmap) d;
394   _mesa_add_renderbuffer(&b->mesa_buffer, BUFFER_FRONT_LEFT,
395                          &b->frontxrb->Base);
396
397   /*
398    * Back renderbuffer
399    */
400   if (vis->mesa_visual.doubleBufferMode) {
401      b->backxrb = xmesa_new_renderbuffer(NULL, 0, &vis->mesa_visual, GL_TRUE);
402      if (!b->backxrb) {
403         /* XXX free front xrb too */
404         _mesa_free(b);
405         return NULL;
406      }
407      b->backxrb->Parent = b;
408      /* determine back buffer implementation */
409      b->db_mode = vis->ximage_flag ? BACK_XIMAGE : BACK_PIXMAP;
410
411      _mesa_add_renderbuffer(&b->mesa_buffer, BUFFER_BACK_LEFT,
412                             &b->backxrb->Base);
413   }
414
415   /*
416    * Software alpha planes
417    */
418   if (vis->mesa_visual.alphaBits > 0
419       && vis->undithered_pf != PF_8A8B8G8R
420       && vis->undithered_pf != PF_8A8R8G8B) {
421      /* Visual has alpha, but pixel format doesn't support it.
422       * We'll use an alpha renderbuffer wrapper.
423       */
424      swAlpha = GL_TRUE;
425   }
426   else {
427      swAlpha = GL_FALSE;
428   }
429
430   /*
431    * Other renderbuffer (depth, stencil, etc)
432    */
433   _mesa_add_soft_renderbuffers(&b->mesa_buffer,
434                                GL_FALSE,  /* color */
435                                vis->mesa_visual.haveDepthBuffer,
436                                vis->mesa_visual.haveStencilBuffer,
437                                vis->mesa_visual.haveAccumBuffer,
438                                swAlpha,
439                                vis->mesa_visual.numAuxBuffers > 0 );
440
441   /* insert buffer into linked list */
442   b->Next = XMesaBufferList;
443   XMesaBufferList = b;
444
445   return b;
446}
447
448
449/**
450 * Find an XMesaBuffer by matching X display and colormap but NOT matching
451 * the notThis buffer.
452 */
453XMesaBuffer
454xmesa_find_buffer(XMesaDisplay *dpy, XMesaColormap cmap, XMesaBuffer notThis)
455{
456   XMesaBuffer b;
457   for (b=XMesaBufferList; b; b=b->Next) {
458      if (b->display==dpy && b->cmap==cmap && b!=notThis) {
459         return b;
460      }
461   }
462   return NULL;
463}
464
465
466/**
467 * Remove buffer from linked list, delete if no longer referenced.
468 */
469static void
470xmesa_free_buffer(XMesaBuffer buffer)
471{
472   XMesaBuffer prev = NULL, b;
473
474   for (b = XMesaBufferList; b; b = b->Next) {
475      if (b == buffer) {
476         struct gl_framebuffer *fb = &buffer->mesa_buffer;
477
478         /* unlink buffer from list */
479         if (prev)
480            prev->Next = buffer->Next;
481         else
482            XMesaBufferList = buffer->Next;
483
484         /* mark as delete pending */
485         fb->DeletePending = GL_TRUE;
486
487         /* Since the X window for the XMesaBuffer is going away, we don't
488          * want to dereference this pointer in the future.
489          */
490         b->frontxrb->drawable = 0;
491
492         /* Unreference.  If count = zero we'll really delete the buffer */
493         _mesa_unreference_framebuffer(&fb);
494
495         return;
496      }
497      /* continue search */
498      prev = b;
499   }
500   /* buffer not found in XMesaBufferList */
501   _mesa_problem(NULL,"xmesa_free_buffer() - buffer not found\n");
502}
503
504
505/**
506 * Copy X color table stuff from one XMesaBuffer to another.
507 */
508static void
509copy_colortable_info(XMesaBuffer dst, const XMesaBuffer src)
510{
511   MEMCPY(dst->color_table, src->color_table, sizeof(src->color_table));
512   MEMCPY(dst->pixel_to_r, src->pixel_to_r, sizeof(src->pixel_to_r));
513   MEMCPY(dst->pixel_to_g, src->pixel_to_g, sizeof(src->pixel_to_g));
514   MEMCPY(dst->pixel_to_b, src->pixel_to_b, sizeof(src->pixel_to_b));
515   dst->num_alloced = src->num_alloced;
516   MEMCPY(dst->alloced_colors, src->alloced_colors,
517          sizeof(src->alloced_colors));
518}
519
520
521
522/**********************************************************************/
523/*****                   Misc Private Functions                   *****/
524/**********************************************************************/
525
526
527/**
528 * A replacement for XAllocColor.  This function should never
529 * fail to allocate a color.  When XAllocColor fails, we return
530 * the nearest matching color.  If we have to allocate many colors
531 * this function isn't too efficient; the XQueryColors() could be
532 * done just once.
533 * Written by Michael Pichler, Brian Paul, Mark Kilgard
534 * Input:  dpy - X display
535 *         cmap - X colormap
536 *         cmapSize - size of colormap
537 * In/Out: color - the XColor struct
538 * Output:  exact - 1=exact color match, 0=closest match
539 *          alloced - 1=XAlloc worked, 0=XAlloc failed
540 */
541static void
542noFaultXAllocColor( int client,
543                    XMesaDisplay *dpy,
544                    XMesaColormap cmap,
545                    int cmapSize,
546                    XMesaColor *color,
547                    int *exact, int *alloced )
548{
549#ifdef XFree86Server
550   Pixel *ppixIn;
551   xrgb *ctable;
552#else
553   /* we'll try to cache ctable for better remote display performance */
554   static Display *prevDisplay = NULL;
555   static XMesaColormap prevCmap = 0;
556   static int prevCmapSize = 0;
557   static XMesaColor *ctable = NULL;
558#endif
559   XMesaColor subColor;
560   int i, bestmatch;
561   double mindist;       /* 3*2^16^2 exceeds long int precision. */
562
563   (void) client;
564
565   /* First try just using XAllocColor. */
566#ifdef XFree86Server
567   if (AllocColor(cmap,
568		  &color->red, &color->green, &color->blue,
569		  &color->pixel,
570		  client) == Success)
571#else
572   if (XAllocColor(dpy, cmap, color))
573#endif
574   {
575      *exact = 1;
576      *alloced = 1;
577      return;
578   }
579
580   /* Alloc failed, search for closest match */
581
582   /* Retrieve color table entries. */
583   /* XXX alloca candidate. */
584#ifdef XFree86Server
585   ppixIn = (Pixel *) MALLOC(cmapSize * sizeof(Pixel));
586   ctable = (xrgb *) MALLOC(cmapSize * sizeof(xrgb));
587   for (i = 0; i < cmapSize; i++) {
588      ppixIn[i] = i;
589   }
590   QueryColors(cmap, cmapSize, ppixIn, ctable);
591#else
592   if (prevDisplay != dpy || prevCmap != cmap
593       || prevCmapSize != cmapSize || !ctable) {
594      /* free previously cached color table */
595      if (ctable)
596         _mesa_free(ctable);
597      /* Get the color table from X */
598      ctable = (XMesaColor *) MALLOC(cmapSize * sizeof(XMesaColor));
599      assert(ctable);
600      for (i = 0; i < cmapSize; i++) {
601         ctable[i].pixel = i;
602      }
603      XQueryColors(dpy, cmap, ctable, cmapSize);
604      prevDisplay = dpy;
605      prevCmap = cmap;
606      prevCmapSize = cmapSize;
607   }
608#endif
609
610   /* Find best match. */
611   bestmatch = -1;
612   mindist = 0.0;
613   for (i = 0; i < cmapSize; i++) {
614      double dr = 0.30 * ((double) color->red - (double) ctable[i].red);
615      double dg = 0.59 * ((double) color->green - (double) ctable[i].green);
616      double db = 0.11 * ((double) color->blue - (double) ctable[i].blue);
617      double dist = dr * dr + dg * dg + db * db;
618      if (bestmatch < 0 || dist < mindist) {
619         bestmatch = i;
620         mindist = dist;
621      }
622   }
623
624   /* Return result. */
625   subColor.red   = ctable[bestmatch].red;
626   subColor.green = ctable[bestmatch].green;
627   subColor.blue  = ctable[bestmatch].blue;
628   /* Try to allocate the closest match color.  This should only
629    * fail if the cell is read/write.  Otherwise, we're incrementing
630    * the cell's reference count.
631    */
632#ifdef XFree86Server
633   if (AllocColor(cmap,
634		  &subColor.red, &subColor.green, &subColor.blue,
635		  &subColor.pixel,
636		  client) == Success) {
637#else
638   if (XAllocColor(dpy, cmap, &subColor)) {
639#endif
640      *alloced = 1;
641   }
642   else {
643      /* do this to work around a problem reported by Frank Ortega */
644      subColor.pixel = (unsigned long) bestmatch;
645      subColor.red   = ctable[bestmatch].red;
646      subColor.green = ctable[bestmatch].green;
647      subColor.blue  = ctable[bestmatch].blue;
648      subColor.flags = DoRed | DoGreen | DoBlue;
649      *alloced = 0;
650   }
651#ifdef XFree86Server
652   _mesa_free(ppixIn);
653   _mesa_free(ctable);
654#else
655   /* don't free table, save it for next time */
656#endif
657
658   *color = subColor;
659   *exact = 0;
660}
661
662
663
664/**
665 * Do setup for PF_GRAYSCALE pixel format.
666 * Note that buffer may be NULL.
667 */
668static GLboolean
669setup_grayscale(int client, XMesaVisual v,
670                XMesaBuffer buffer, XMesaColormap cmap)
671{
672   if (GET_VISUAL_DEPTH(v)<4 || GET_VISUAL_DEPTH(v)>16) {
673      return GL_FALSE;
674   }
675
676   if (buffer) {
677      XMesaBuffer prevBuffer;
678
679      if (!cmap) {
680         return GL_FALSE;
681      }
682
683      prevBuffer = xmesa_find_buffer(v->display, cmap, buffer);
684      if (prevBuffer &&
685          (buffer->xm_visual->mesa_visual.rgbMode ==
686           prevBuffer->xm_visual->mesa_visual.rgbMode)) {
687         /* Copy colormap stuff from previous XMesaBuffer which uses same
688          * X colormap.  Do this to avoid time spent in noFaultXAllocColor.
689          */
690         copy_colortable_info(buffer, prevBuffer);
691      }
692      else {
693         /* Allocate 256 shades of gray */
694         int gray;
695         int colorsfailed = 0;
696         for (gray=0;gray<256;gray++) {
697            GLint r = gamma_adjust( v->RedGamma,   gray, 255 );
698            GLint g = gamma_adjust( v->GreenGamma, gray, 255 );
699            GLint b = gamma_adjust( v->BlueGamma,  gray, 255 );
700            int exact, alloced;
701            XMesaColor xcol;
702            xcol.red   = (r << 8) | r;
703            xcol.green = (g << 8) | g;
704            xcol.blue  = (b << 8) | b;
705            noFaultXAllocColor( client, v->display,
706                                cmap, GET_COLORMAP_SIZE(v),
707                                &xcol, &exact, &alloced );
708            if (!exact) {
709               colorsfailed++;
710            }
711            if (alloced) {
712               assert(buffer->num_alloced<256);
713               buffer->alloced_colors[buffer->num_alloced] = xcol.pixel;
714               buffer->num_alloced++;
715            }
716
717            /*OLD
718            assert(gray < 576);
719            buffer->color_table[gray*3+0] = xcol.pixel;
720            buffer->color_table[gray*3+1] = xcol.pixel;
721            buffer->color_table[gray*3+2] = xcol.pixel;
722            assert(xcol.pixel < 65536);
723            buffer->pixel_to_r[xcol.pixel] = gray * 30 / 100;
724            buffer->pixel_to_g[xcol.pixel] = gray * 59 / 100;
725            buffer->pixel_to_b[xcol.pixel] = gray * 11 / 100;
726            */
727            buffer->color_table[gray] = xcol.pixel;
728            assert(xcol.pixel < 65536);
729            buffer->pixel_to_r[xcol.pixel] = gray;
730            buffer->pixel_to_g[xcol.pixel] = gray;
731            buffer->pixel_to_b[xcol.pixel] = gray;
732         }
733
734         if (colorsfailed && _mesa_getenv("MESA_DEBUG")) {
735            _mesa_warning(NULL,
736                  "Note: %d out of 256 needed colors do not match exactly.\n",
737                  colorsfailed );
738         }
739      }
740   }
741
742   v->dithered_pf = PF_Grayscale;
743   v->undithered_pf = PF_Grayscale;
744   return GL_TRUE;
745}
746
747
748
749/**
750 * Setup RGB rendering for a window with a PseudoColor, StaticColor,
751 * or 8-bit TrueColor visual visual.  We try to allocate a palette of 225
752 * colors (5 red, 9 green, 5 blue) and dither to approximate a 24-bit RGB
753 * color.  While this function was originally designed just for 8-bit
754 * visuals, it has also proven to work from 4-bit up to 16-bit visuals.
755 * Dithering code contributed by Bob Mercier.
756 */
757static GLboolean
758setup_dithered_color(int client, XMesaVisual v,
759                     XMesaBuffer buffer, XMesaColormap cmap)
760{
761   if (GET_VISUAL_DEPTH(v)<4 || GET_VISUAL_DEPTH(v)>16) {
762      return GL_FALSE;
763   }
764
765   if (buffer) {
766      XMesaBuffer prevBuffer;
767
768      if (!cmap) {
769         return GL_FALSE;
770      }
771
772      prevBuffer = xmesa_find_buffer(v->display, cmap, buffer);
773      if (prevBuffer &&
774          (buffer->xm_visual->mesa_visual.rgbMode ==
775           prevBuffer->xm_visual->mesa_visual.rgbMode)) {
776         /* Copy colormap stuff from previous, matching XMesaBuffer.
777          * Do this to avoid time spent in noFaultXAllocColor.
778          */
779         copy_colortable_info(buffer, prevBuffer);
780      }
781      else {
782         /* Allocate X colors and initialize color_table[], red_table[], etc */
783         int r, g, b, i;
784         int colorsfailed = 0;
785         for (r = 0; r < DITH_R; r++) {
786            for (g = 0; g < DITH_G; g++) {
787               for (b = 0; b < DITH_B; b++) {
788                  XMesaColor xcol;
789                  int exact, alloced;
790                  xcol.red  =gamma_adjust(v->RedGamma,   r*65535/(DITH_R-1),65535);
791                  xcol.green=gamma_adjust(v->GreenGamma, g*65535/(DITH_G-1),65535);
792                  xcol.blue =gamma_adjust(v->BlueGamma,  b*65535/(DITH_B-1),65535);
793                  noFaultXAllocColor( client, v->display,
794                                      cmap, GET_COLORMAP_SIZE(v),
795                                      &xcol, &exact, &alloced );
796                  if (!exact) {
797                     colorsfailed++;
798                  }
799                  if (alloced) {
800                     assert(buffer->num_alloced<256);
801                     buffer->alloced_colors[buffer->num_alloced] = xcol.pixel;
802                     buffer->num_alloced++;
803                  }
804                  i = DITH_MIX( r, g, b );
805                  assert(i < 576);
806                  buffer->color_table[i] = xcol.pixel;
807                  assert(xcol.pixel < 65536);
808                  buffer->pixel_to_r[xcol.pixel] = r * 255 / (DITH_R-1);
809                  buffer->pixel_to_g[xcol.pixel] = g * 255 / (DITH_G-1);
810                  buffer->pixel_to_b[xcol.pixel] = b * 255 / (DITH_B-1);
811               }
812            }
813         }
814
815         if (colorsfailed && _mesa_getenv("MESA_DEBUG")) {
816            _mesa_warning(NULL,
817                  "Note: %d out of %d needed colors do not match exactly.\n",
818                  colorsfailed, DITH_R * DITH_G * DITH_B );
819         }
820      }
821   }
822
823   v->dithered_pf = PF_Dither;
824   v->undithered_pf = PF_Lookup;
825   return GL_TRUE;
826}
827
828
829/**
830 * Setup for Hewlett Packard Color Recovery 8-bit TrueColor mode.
831 * HPCR simulates 24-bit color fidelity with an 8-bit frame buffer.
832 * Special dithering tables have to be initialized.
833 */
834static void
835setup_8bit_hpcr(XMesaVisual v)
836{
837   /* HP Color Recovery contributed by:  Alex De Bruyn (ad@lms.be)
838    * To work properly, the atom _HP_RGB_SMOOTH_MAP_LIST must be defined
839    * on the root window AND the colormap obtainable by XGetRGBColormaps
840    * for that atom must be set on the window.  (see also tkInitWindow)
841    * If that colormap is not set, the output will look stripy.
842    */
843
844   /* Setup color tables with gamma correction */
845   int i;
846   double g;
847
848   g = 1.0 / v->RedGamma;
849   for (i=0; i<256; i++) {
850      GLint red = IROUND_POS(255.0 * _mesa_pow( hpcr_rgbTbl[0][i]/255.0, g ));
851      v->hpcr_rgbTbl[0][i] = CLAMP( red, 16, 239 );
852   }
853
854   g = 1.0 / v->GreenGamma;
855   for (i=0; i<256; i++) {
856      GLint green = IROUND_POS(255.0 * _mesa_pow( hpcr_rgbTbl[1][i]/255.0, g ));
857      v->hpcr_rgbTbl[1][i] = CLAMP( green, 16, 239 );
858   }
859
860   g = 1.0 / v->BlueGamma;
861   for (i=0; i<256; i++) {
862      GLint blue = IROUND_POS(255.0 * _mesa_pow( hpcr_rgbTbl[2][i]/255.0, g ));
863      v->hpcr_rgbTbl[2][i] = CLAMP( blue, 32, 223 );
864   }
865   v->undithered_pf = PF_HPCR;  /* can't really disable dithering for now */
866   v->dithered_pf = PF_HPCR;
867
868   /* which method should I use to clear */
869   /* GL_FALSE: keep the ordinary method  */
870   /* GL_TRUE : clear with dither pattern */
871   v->hpcr_clear_flag = _mesa_getenv("MESA_HPCR_CLEAR") ? GL_TRUE : GL_FALSE;
872
873   if (v->hpcr_clear_flag) {
874      v->hpcr_clear_pixmap = XMesaCreatePixmap(v->display,
875                                               DefaultRootWindow(v->display),
876                                               16, 2, 8);
877#ifndef XFree86Server
878      v->hpcr_clear_ximage = XGetImage(v->display, v->hpcr_clear_pixmap,
879                                       0, 0, 16, 2, AllPlanes, ZPixmap);
880#endif
881   }
882}
883
884
885/**
886 * Setup RGB rendering for a window with a True/DirectColor visual.
887 */
888static void
889setup_truecolor(XMesaVisual v, XMesaBuffer buffer, XMesaColormap cmap)
890{
891   unsigned long rmask, gmask, bmask;
892   (void) buffer;
893   (void) cmap;
894
895   /* Compute red multiplier (mask) and bit shift */
896   v->rshift = 0;
897   rmask = GET_REDMASK(v);
898   while ((rmask & 1)==0) {
899      v->rshift++;
900      rmask = rmask >> 1;
901   }
902
903   /* Compute green multiplier (mask) and bit shift */
904   v->gshift = 0;
905   gmask = GET_GREENMASK(v);
906   while ((gmask & 1)==0) {
907      v->gshift++;
908      gmask = gmask >> 1;
909   }
910
911   /* Compute blue multiplier (mask) and bit shift */
912   v->bshift = 0;
913   bmask = GET_BLUEMASK(v);
914   while ((bmask & 1)==0) {
915      v->bshift++;
916      bmask = bmask >> 1;
917   }
918
919   /*
920    * Compute component-to-pixel lookup tables and dithering kernel
921    */
922   {
923      static GLubyte kernel[16] = {
924          0*16,  8*16,  2*16, 10*16,
925         12*16,  4*16, 14*16,  6*16,
926          3*16, 11*16,  1*16,  9*16,
927         15*16,  7*16, 13*16,  5*16,
928      };
929      GLint rBits = _mesa_bitcount(rmask);
930      GLint gBits = _mesa_bitcount(gmask);
931      GLint bBits = _mesa_bitcount(bmask);
932      GLint maxBits;
933      GLuint i;
934
935      /* convert pixel components in [0,_mask] to RGB values in [0,255] */
936      for (i=0; i<=rmask; i++)
937         v->PixelToR[i] = (unsigned char) ((i * 255) / rmask);
938      for (i=0; i<=gmask; i++)
939         v->PixelToG[i] = (unsigned char) ((i * 255) / gmask);
940      for (i=0; i<=bmask; i++)
941         v->PixelToB[i] = (unsigned char) ((i * 255) / bmask);
942
943      /* convert RGB values from [0,255] to pixel components */
944
945      for (i=0;i<256;i++) {
946         GLint r = gamma_adjust(v->RedGamma,   i, 255);
947         GLint g = gamma_adjust(v->GreenGamma, i, 255);
948         GLint b = gamma_adjust(v->BlueGamma,  i, 255);
949         v->RtoPixel[i] = (r >> (8-rBits)) << v->rshift;
950         v->GtoPixel[i] = (g >> (8-gBits)) << v->gshift;
951         v->BtoPixel[i] = (b >> (8-bBits)) << v->bshift;
952      }
953      /* overflow protection */
954      for (i=256;i<512;i++) {
955         v->RtoPixel[i] = v->RtoPixel[255];
956         v->GtoPixel[i] = v->GtoPixel[255];
957         v->BtoPixel[i] = v->BtoPixel[255];
958      }
959
960      /* setup dithering kernel */
961      maxBits = rBits;
962      if (gBits > maxBits)  maxBits = gBits;
963      if (bBits > maxBits)  maxBits = bBits;
964      for (i=0;i<16;i++) {
965         v->Kernel[i] = kernel[i] >> maxBits;
966      }
967
968      v->undithered_pf = PF_Truecolor;
969      v->dithered_pf = (GET_VISUAL_DEPTH(v)<24) ? PF_Dither_True : PF_Truecolor;
970   }
971
972   /*
973    * Now check for TrueColor visuals which we can optimize.
974    */
975   if (   GET_REDMASK(v)  ==0x0000ff
976       && GET_GREENMASK(v)==0x00ff00
977       && GET_BLUEMASK(v) ==0xff0000
978       && CHECK_BYTE_ORDER(v)
979       && v->BitsPerPixel==32
980       && sizeof(GLuint)==4
981       && v->RedGamma==1.0 && v->GreenGamma==1.0 && v->BlueGamma==1.0) {
982      /* common 32 bpp config used on SGI, Sun */
983      v->undithered_pf = v->dithered_pf = PF_8A8B8G8R;
984   }
985   else if (GET_REDMASK(v)  ==0xff0000
986       &&   GET_GREENMASK(v)==0x00ff00
987       &&   GET_BLUEMASK(v) ==0x0000ff
988       && CHECK_BYTE_ORDER(v)
989       && v->BitsPerPixel==32
990       && sizeof(GLuint)==4
991       && v->RedGamma==1.0 && v->GreenGamma==1.0 && v->BlueGamma==1.0) {
992      /* common 32 bpp config used on Linux, HP, IBM */
993      if (GET_VISUAL_DEPTH(v)==32)
994	  v->undithered_pf = v->dithered_pf = PF_8A8R8G8B;
995      else
996	  v->undithered_pf = v->dithered_pf = PF_8R8G8B;
997   }
998   else if (GET_REDMASK(v)  ==0xff0000
999       &&   GET_GREENMASK(v)==0x00ff00
1000       &&   GET_BLUEMASK(v) ==0x0000ff
1001       && CHECK_BYTE_ORDER(v)
1002       && v->BitsPerPixel==24
1003       && sizeof(GLuint)==4
1004       && v->RedGamma==1.0 && v->GreenGamma==1.0 && v->BlueGamma==1.0) {
1005      /* common packed 24 bpp config used on Linux */
1006      v->undithered_pf = v->dithered_pf = PF_8R8G8B24;
1007   }
1008   else if (GET_REDMASK(v)  ==0xf800
1009       &&   GET_GREENMASK(v)==0x07e0
1010       &&   GET_BLUEMASK(v) ==0x001f
1011       && CHECK_BYTE_ORDER(v)
1012       && v->BitsPerPixel==16
1013       && sizeof(GLushort)==2
1014       && v->RedGamma==1.0 && v->GreenGamma==1.0 && v->BlueGamma==1.0) {
1015      /* 5-6-5 color weight on common PC VGA boards */
1016      v->undithered_pf = PF_5R6G5B;
1017      v->dithered_pf = PF_Dither_5R6G5B;
1018   }
1019   else if (GET_REDMASK(v)  ==0xe0
1020       &&   GET_GREENMASK(v)==0x1c
1021       &&   GET_BLUEMASK(v) ==0x03
1022       && CHECK_FOR_HPCR(v)) {
1023      setup_8bit_hpcr( v );
1024   }
1025}
1026
1027
1028
1029/**
1030 * Setup RGB rendering for a window with a monochrome visual.
1031 */
1032static void
1033setup_monochrome( XMesaVisual v, XMesaBuffer b )
1034{
1035   (void) b;
1036   v->dithered_pf = v->undithered_pf = PF_1Bit;
1037   /* if black=1 then we must flip pixel values */
1038   v->bitFlip = (GET_BLACK_PIXEL(v) != 0);
1039}
1040
1041
1042
1043/**
1044 * When a context is bound for the first time, we can finally finish
1045 * initializing the context's visual and buffer information.
1046 * \param v  the XMesaVisual to initialize
1047 * \param b  the XMesaBuffer to initialize (may be NULL)
1048 * \param rgb_flag  TRUE = RGBA mode, FALSE = color index mode
1049 * \param window  the window/pixmap we're rendering into
1050 * \param cmap  the colormap associated with the window/pixmap
1051 * \return GL_TRUE=success, GL_FALSE=failure
1052 */
1053static GLboolean
1054initialize_visual_and_buffer(int client, XMesaVisual v, XMesaBuffer b,
1055                             GLboolean rgb_flag, XMesaDrawable window,
1056                             XMesaColormap cmap)
1057{
1058   ASSERT(!b || b->xm_visual == v);
1059
1060   /* Save true bits/pixel */
1061   v->BitsPerPixel = bits_per_pixel(v);
1062   assert(v->BitsPerPixel > 0);
1063
1064   if (rgb_flag == GL_FALSE) {
1065      /* COLOR-INDEXED WINDOW:
1066       * Even if the visual is TrueColor or DirectColor we treat it as
1067       * being color indexed.  This is weird but might be useful to someone.
1068       */
1069      v->dithered_pf = v->undithered_pf = PF_Index;
1070      v->mesa_visual.indexBits = GET_VISUAL_DEPTH(v);
1071   }
1072   else {
1073      /* RGB WINDOW:
1074       * We support RGB rendering into almost any kind of visual.
1075       */
1076      const int xclass = v->mesa_visual.visualType;
1077      if (xclass == GLX_TRUE_COLOR || xclass == GLX_DIRECT_COLOR) {
1078	 setup_truecolor( v, b, cmap );
1079      }
1080      else if (xclass == GLX_STATIC_GRAY && GET_VISUAL_DEPTH(v) == 1) {
1081	 setup_monochrome( v, b );
1082      }
1083      else if (xclass == GLX_GRAY_SCALE || xclass == GLX_STATIC_GRAY) {
1084         if (!setup_grayscale( client, v, b, cmap )) {
1085            return GL_FALSE;
1086         }
1087      }
1088      else if ((xclass == GLX_PSEUDO_COLOR || xclass == GLX_STATIC_COLOR)
1089               && GET_VISUAL_DEPTH(v)>=4 && GET_VISUAL_DEPTH(v)<=16) {
1090	 if (!setup_dithered_color( client, v, b, cmap )) {
1091            return GL_FALSE;
1092         }
1093      }
1094      else {
1095	 _mesa_warning(NULL, "XMesa: RGB mode rendering not supported in given visual.\n");
1096	 return GL_FALSE;
1097      }
1098      v->mesa_visual.indexBits = 0;
1099
1100      if (_mesa_getenv("MESA_NO_DITHER")) {
1101	 v->dithered_pf = v->undithered_pf;
1102      }
1103   }
1104
1105
1106   /*
1107    * If MESA_INFO env var is set print out some debugging info
1108    * which can help Brian figure out what's going on when a user
1109    * reports bugs.
1110    */
1111   if (_mesa_getenv("MESA_INFO")) {
1112      _mesa_printf("X/Mesa visual = %p\n", (void *) v);
1113      _mesa_printf("X/Mesa dithered pf = %u\n", v->dithered_pf);
1114      _mesa_printf("X/Mesa undithered pf = %u\n", v->undithered_pf);
1115      _mesa_printf("X/Mesa level = %d\n", v->mesa_visual.level);
1116      _mesa_printf("X/Mesa depth = %d\n", GET_VISUAL_DEPTH(v));
1117      _mesa_printf("X/Mesa bits per pixel = %d\n", v->BitsPerPixel);
1118   }
1119
1120   if (b && window) {
1121      /* Do window-specific initializations */
1122
1123      /* these should have been set in create_xmesa_buffer */
1124      ASSERT(b->frontxrb->drawable == window);
1125      ASSERT(b->frontxrb->pixmap == (XMesaPixmap) window);
1126
1127      /* Setup for single/double buffering */
1128      if (v->mesa_visual.doubleBufferMode) {
1129         /* Double buffered */
1130         b->shm = check_for_xshm( v->display );
1131      }
1132
1133      /* X11 graphics contexts */
1134#ifdef XFree86Server
1135      b->gc = CreateScratchGC(v->display, window->depth);
1136#else
1137      b->gc = XCreateGC( v->display, window, 0, NULL );
1138#endif
1139      XMesaSetFunction( v->display, b->gc, GXcopy );
1140
1141      /* cleargc - for glClear() */
1142#ifdef XFree86Server
1143      b->cleargc = CreateScratchGC(v->display, window->depth);
1144#else
1145      b->cleargc = XCreateGC( v->display, window, 0, NULL );
1146#endif
1147      XMesaSetFunction( v->display, b->cleargc, GXcopy );
1148
1149      /*
1150       * Don't generate Graphics Expose/NoExpose events in swapbuffers().
1151       * Patch contributed by Michael Pichler May 15, 1995.
1152       */
1153#ifdef XFree86Server
1154      b->swapgc = CreateScratchGC(v->display, window->depth);
1155      {
1156         CARD32 v[1];
1157         v[0] = FALSE;
1158         dixChangeGC(NullClient, b->swapgc, GCGraphicsExposures, v, NULL);
1159      }
1160#else
1161      {
1162         XGCValues gcvalues;
1163         gcvalues.graphics_exposures = False;
1164         b->swapgc = XCreateGC(v->display, window,
1165                               GCGraphicsExposures, &gcvalues);
1166      }
1167#endif
1168      XMesaSetFunction( v->display, b->swapgc, GXcopy );
1169      /*
1170       * Set fill style and tile pixmap once for all for HPCR stuff
1171       * (instead of doing it each time in clear_color_HPCR_pixmap())
1172       * Initialize whole stuff
1173       * Patch contributed by Jacques Leroy March 8, 1998.
1174       */
1175      if (v->hpcr_clear_flag && b->backxrb && b->backxrb->pixmap) {
1176         int i;
1177         for (i = 0; i < 16; i++) {
1178            XMesaPutPixel(v->hpcr_clear_ximage, i, 0, 0);
1179            XMesaPutPixel(v->hpcr_clear_ximage, i, 1, 0);
1180         }
1181         XMesaPutImage(b->display, (XMesaDrawable) v->hpcr_clear_pixmap,
1182                       b->cleargc, v->hpcr_clear_ximage, 0, 0, 0, 0, 16, 2);
1183         XMesaSetFillStyle( v->display, b->cleargc, FillTiled);
1184         XMesaSetTile( v->display, b->cleargc, v->hpcr_clear_pixmap );
1185      }
1186
1187      /* Initialize the row buffer XImage for use in write_color_span() */
1188#ifdef XFree86Server
1189      b->rowimage = XMesaCreateImage(GET_VISUAL_DEPTH(v), MAX_WIDTH, 1,
1190				     (char *)MALLOC(MAX_WIDTH*4));
1191#else
1192      b->rowimage = XCreateImage( v->display,
1193                                  v->visinfo->visual,
1194                                  v->visinfo->depth,
1195                                  ZPixmap, 0,           /*format, offset*/
1196                                  (char*) MALLOC(MAX_WIDTH*4),  /*data*/
1197                                  MAX_WIDTH, 1,         /*width, height*/
1198                                  32,                   /*bitmap_pad*/
1199                                  0                     /*bytes_per_line*/ );
1200#endif
1201      if (!b->rowimage)
1202         return GL_FALSE;
1203   }
1204
1205   return GL_TRUE;
1206}
1207
1208
1209
1210/*
1211 * Convert an RGBA color to a pixel value.
1212 */
1213unsigned long
1214xmesa_color_to_pixel(GLcontext *ctx,
1215                     GLubyte r, GLubyte g, GLubyte b, GLubyte a,
1216                     GLuint pixelFormat)
1217{
1218   XMesaContext xmesa = XMESA_CONTEXT(ctx);
1219   switch (pixelFormat) {
1220      case PF_Index:
1221         return 0;
1222      case PF_Truecolor:
1223         {
1224            unsigned long p;
1225            PACK_TRUECOLOR( p, r, g, b );
1226            return p;
1227         }
1228      case PF_8A8B8G8R:
1229         return PACK_8A8B8G8R( r, g, b, a );
1230      case PF_8A8R8G8B:
1231         return PACK_8A8R8G8B( r, g, b, a );
1232      case PF_8R8G8B:
1233         /* fall through */
1234      case PF_8R8G8B24:
1235         return PACK_8R8G8B( r, g, b );
1236      case PF_5R6G5B:
1237         return PACK_5R6G5B( r, g, b );
1238      case PF_Dither:
1239         {
1240            DITHER_SETUP;
1241            return DITHER( 1, 0, r, g, b );
1242         }
1243      case PF_1Bit:
1244         /* 382 = (3*255)/2 */
1245         return ((r+g+b) > 382) ^ xmesa->xm_visual->bitFlip;
1246      case PF_HPCR:
1247         return DITHER_HPCR(1, 1, r, g, b);
1248      case PF_Lookup:
1249         {
1250            LOOKUP_SETUP;
1251            return LOOKUP( r, g, b );
1252         }
1253      case PF_Grayscale:
1254         return GRAY_RGB( r, g, b );
1255      case PF_Dither_True:
1256         /* fall through */
1257      case PF_Dither_5R6G5B:
1258         {
1259            unsigned long p;
1260            PACK_TRUEDITHER(p, 1, 0, r, g, b);
1261            return p;
1262         }
1263      default:
1264         _mesa_problem(ctx, "Bad pixel format in xmesa_color_to_pixel");
1265   }
1266   return 0;
1267}
1268
1269
1270#define NUM_VISUAL_TYPES   6
1271
1272/**
1273 * Convert an X visual type to a GLX visual type.
1274 *
1275 * \param visualType X visual type (i.e., \c TrueColor, \c StaticGray, etc.)
1276 *        to be converted.
1277 * \return If \c visualType is a valid X visual type, a GLX visual type will
1278 *         be returned.  Otherwise \c GLX_NONE will be returned.
1279 *
1280 * \note
1281 * This code was lifted directly from lib/GL/glx/glcontextmodes.c in the
1282 * DRI CVS tree.
1283 */
1284static GLint
1285xmesa_convert_from_x_visual_type( int visualType )
1286{
1287    static const int glx_visual_types[ NUM_VISUAL_TYPES ] = {
1288	GLX_STATIC_GRAY,  GLX_GRAY_SCALE,
1289	GLX_STATIC_COLOR, GLX_PSEUDO_COLOR,
1290	GLX_TRUE_COLOR,   GLX_DIRECT_COLOR
1291    };
1292
1293    return ( (unsigned) visualType < NUM_VISUAL_TYPES )
1294	? glx_visual_types[ visualType ] : GLX_NONE;
1295}
1296
1297
1298/**********************************************************************/
1299/*****                       Public Functions                     *****/
1300/**********************************************************************/
1301
1302
1303/*
1304 * Create a new X/Mesa visual.
1305 * Input:  display - X11 display
1306 *         visinfo - an XVisualInfo pointer
1307 *         rgb_flag - GL_TRUE = RGB mode,
1308 *                    GL_FALSE = color index mode
1309 *         alpha_flag - alpha buffer requested?
1310 *         db_flag - GL_TRUE = double-buffered,
1311 *                   GL_FALSE = single buffered
1312 *         stereo_flag - stereo visual?
1313 *         ximage_flag - GL_TRUE = use an XImage for back buffer,
1314 *                       GL_FALSE = use an off-screen pixmap for back buffer
1315 *         depth_size - requested bits/depth values, or zero
1316 *         stencil_size - requested bits/stencil values, or zero
1317 *         accum_red_size - requested bits/red accum values, or zero
1318 *         accum_green_size - requested bits/green accum values, or zero
1319 *         accum_blue_size - requested bits/blue accum values, or zero
1320 *         accum_alpha_size - requested bits/alpha accum values, or zero
1321 *         num_samples - number of samples/pixel if multisampling, or zero
1322 *         level - visual level, usually 0
1323 *         visualCaveat - ala the GLX extension, usually GLX_NONE
1324 * Return;  a new XMesaVisual or 0 if error.
1325 */
1326XMesaVisual XMesaCreateVisual( XMesaDisplay *display,
1327                               XMesaVisualInfo visinfo,
1328                               GLboolean rgb_flag,
1329                               GLboolean alpha_flag,
1330                               GLboolean db_flag,
1331                               GLboolean stereo_flag,
1332                               GLboolean ximage_flag,
1333                               GLint depth_size,
1334                               GLint stencil_size,
1335                               GLint accum_red_size,
1336                               GLint accum_green_size,
1337                               GLint accum_blue_size,
1338                               GLint accum_alpha_size,
1339                               GLint num_samples,
1340                               GLint level,
1341                               GLint visualCaveat )
1342{
1343   char *gamma;
1344   XMesaVisual v;
1345   GLint red_bits, green_bits, blue_bits, alpha_bits;
1346
1347#ifndef XFree86Server
1348   /* For debugging only */
1349   if (_mesa_getenv("MESA_XSYNC")) {
1350      /* This makes debugging X easier.
1351       * In your debugger, set a breakpoint on _XError to stop when an
1352       * X protocol error is generated.
1353       */
1354      XSynchronize( display, 1 );
1355   }
1356#endif
1357
1358   v = (XMesaVisual) CALLOC_STRUCT(xmesa_visual);
1359   if (!v) {
1360      return NULL;
1361   }
1362
1363   /*
1364    * In the X server, NULL is passed in for the display.  It will have
1365    * to be set before using this visual.  See XMesaSetVisualDisplay()
1366    * below.
1367    */
1368   v->display = display;
1369
1370   /* Save a copy of the XVisualInfo struct because the user may X_mesa_free()
1371    * the struct but we may need some of the information contained in it
1372    * at a later time.
1373    */
1374#ifndef XFree86Server
1375   v->visinfo = (XVisualInfo *) MALLOC(sizeof(*visinfo));
1376   if(!v->visinfo) {
1377      _mesa_free(v);
1378      return NULL;
1379   }
1380   MEMCPY(v->visinfo, visinfo, sizeof(*visinfo));
1381#endif
1382
1383   /* check for MESA_GAMMA environment variable */
1384   gamma = _mesa_getenv("MESA_GAMMA");
1385   if (gamma) {
1386      v->RedGamma = v->GreenGamma = v->BlueGamma = 0.0;
1387      sscanf( gamma, "%f %f %f", &v->RedGamma, &v->GreenGamma, &v->BlueGamma );
1388      if (v->RedGamma<=0.0)    v->RedGamma = 1.0;
1389      if (v->GreenGamma<=0.0)  v->GreenGamma = v->RedGamma;
1390      if (v->BlueGamma<=0.0)   v->BlueGamma = v->RedGamma;
1391   }
1392   else {
1393      v->RedGamma = v->GreenGamma = v->BlueGamma = 1.0;
1394   }
1395
1396   v->ximage_flag = ximage_flag;
1397
1398#ifdef XFree86Server
1399   /* We could calculate these values by ourselves.  nplanes is either the sum
1400    * of the red, green, and blue bits or the number index bits.
1401    * ColormapEntries is either (1U << index_bits) or
1402    * (1U << max(redBits, greenBits, blueBits)).
1403    */
1404   assert(visinfo->nplanes > 0);
1405   v->nplanes = visinfo->nplanes;
1406   v->ColormapEntries = visinfo->ColormapEntries;
1407
1408   v->mesa_visual.redMask = visinfo->redMask;
1409   v->mesa_visual.greenMask = visinfo->greenMask;
1410   v->mesa_visual.blueMask = visinfo->blueMask;
1411   v->mesa_visual.visualID = visinfo->vid;
1412   v->mesa_visual.screen = 0; /* FIXME: What should be done here? */
1413#else
1414   v->mesa_visual.redMask = visinfo->red_mask;
1415   v->mesa_visual.greenMask = visinfo->green_mask;
1416   v->mesa_visual.blueMask = visinfo->blue_mask;
1417   v->mesa_visual.visualID = visinfo->visualid;
1418   v->mesa_visual.screen = visinfo->screen;
1419#endif
1420
1421#if defined(XFree86Server) || !(defined(__cplusplus) || defined(c_plusplus))
1422   v->mesa_visual.visualType = xmesa_convert_from_x_visual_type(visinfo->class);
1423#else
1424   v->mesa_visual.visualType = xmesa_convert_from_x_visual_type(visinfo->c_class);
1425#endif
1426
1427   v->mesa_visual.visualRating = visualCaveat;
1428
1429   (void) initialize_visual_and_buffer( 0, v, NULL, rgb_flag, 0, 0 );
1430
1431   {
1432      const int xclass = v->mesa_visual.visualType;
1433      if (xclass == GLX_TRUE_COLOR || xclass == GLX_DIRECT_COLOR) {
1434         red_bits   = _mesa_bitcount(GET_REDMASK(v));
1435         green_bits = _mesa_bitcount(GET_GREENMASK(v));
1436         blue_bits  = _mesa_bitcount(GET_BLUEMASK(v));
1437         alpha_bits = 0;
1438      }
1439      else {
1440         /* this is an approximation */
1441         int depth;
1442         depth = GET_VISUAL_DEPTH(v);
1443         red_bits = depth / 3;
1444         depth -= red_bits;
1445         green_bits = depth / 2;
1446         depth -= green_bits;
1447         blue_bits = depth;
1448         alpha_bits = 0;
1449         assert( red_bits + green_bits + blue_bits == GET_VISUAL_DEPTH(v) );
1450      }
1451   }
1452
1453   if (alpha_flag && alpha_bits == 0)
1454      alpha_bits = 8;
1455
1456   _mesa_initialize_visual( &v->mesa_visual,
1457                            rgb_flag, db_flag, stereo_flag,
1458                            red_bits, green_bits,
1459                            blue_bits, alpha_bits,
1460                            v->mesa_visual.indexBits,
1461                            depth_size,
1462                            stencil_size,
1463                            accum_red_size, accum_green_size,
1464                            accum_blue_size, accum_alpha_size,
1465                            0 );
1466
1467   /* XXX minor hack */
1468   v->mesa_visual.level = level;
1469   return v;
1470}
1471
1472
1473void XMesaSetVisualDisplay( XMesaDisplay *dpy, XMesaVisual v )
1474{
1475    v->display = dpy;
1476}
1477
1478
1479void XMesaDestroyVisual( XMesaVisual v )
1480{
1481#ifndef XFree86Server
1482   _mesa_free(v->visinfo);
1483#endif
1484   _mesa_free(v);
1485}
1486
1487
1488
1489/**
1490 * Create a new XMesaContext.
1491 * \param v  the XMesaVisual
1492 * \param share_list  another XMesaContext with which to share display
1493 *                    lists or NULL if no sharing is wanted.
1494 * \return an XMesaContext or NULL if error.
1495 */
1496XMesaContext XMesaCreateContext( XMesaVisual v, XMesaContext share_list )
1497{
1498   static GLboolean firstTime = GL_TRUE;
1499   XMesaContext c;
1500   GLcontext *mesaCtx;
1501   struct dd_function_table functions;
1502   TNLcontext *tnl;
1503
1504   if (firstTime) {
1505      _glthread_INIT_MUTEX(_xmesa_lock);
1506      firstTime = GL_FALSE;
1507   }
1508
1509   /* Note: the XMesaContext contains a Mesa GLcontext struct (inheritance) */
1510   c = (XMesaContext) CALLOC_STRUCT(xmesa_context);
1511   if (!c)
1512      return NULL;
1513
1514   mesaCtx = &(c->mesa);
1515
1516   /* initialize with default driver functions, then plug in XMesa funcs */
1517   _mesa_init_driver_functions(&functions);
1518   xmesa_init_driver_functions(v, &functions);
1519   if (!_mesa_initialize_context(mesaCtx, &v->mesa_visual,
1520                      share_list ? &(share_list->mesa) : (GLcontext *) NULL,
1521                      &functions, (void *) c)) {
1522      _mesa_free(c);
1523      return NULL;
1524   }
1525
1526   _mesa_enable_sw_extensions(mesaCtx);
1527   _mesa_enable_1_3_extensions(mesaCtx);
1528   _mesa_enable_1_4_extensions(mesaCtx);
1529   _mesa_enable_1_5_extensions(mesaCtx);
1530   _mesa_enable_2_0_extensions(mesaCtx);
1531#if ENABLE_EXT_texure_compression_s3tc
1532    if (c->Mesa_DXTn) {
1533       _mesa_enable_extension(mesaCtx, "GL_EXT_texture_compression_s3tc");
1534       _mesa_enable_extension(mesaCtx, "GL_S3_s3tc");
1535    }
1536    _mesa_enable_extension(mesaCtx, "GL_3DFX_texture_compression_FXT1");
1537#endif
1538#if ENABLE_EXT_timer_query
1539    _mesa_enable_extension(mesaCtx, "GL_EXT_timer_query");
1540#endif
1541
1542#ifdef XFree86Server
1543   /* If we're running in the X server, do bounds checking to prevent
1544    * segfaults and server crashes!
1545    */
1546   mesaCtx->Const.CheckArrayBounds = GL_TRUE;
1547#endif
1548
1549   /* finish up xmesa context initializations */
1550   c->swapbytes = CHECK_BYTE_ORDER(v) ? GL_FALSE : GL_TRUE;
1551   c->xm_visual = v;
1552   c->xm_buffer = NULL;   /* set later by XMesaMakeCurrent */
1553   c->display = v->display;
1554   c->pixelformat = v->dithered_pf;      /* Dithering is enabled by default */
1555
1556   /* Initialize the software rasterizer and helper modules.
1557    */
1558   if (!_swrast_CreateContext( mesaCtx ) ||
1559       !_vbo_CreateContext( mesaCtx ) ||
1560       !_tnl_CreateContext( mesaCtx ) ||
1561       !_swsetup_CreateContext( mesaCtx )) {
1562      _mesa_free_context_data(&c->mesa);
1563      _mesa_free(c);
1564      return NULL;
1565   }
1566
1567   /* tnl setup */
1568   tnl = TNL_CONTEXT(mesaCtx);
1569   tnl->Driver.RunPipeline = _tnl_run_pipeline;
1570   /* swrast setup */
1571   xmesa_register_swrast_functions( mesaCtx );
1572   _swsetup_Wakeup(mesaCtx);
1573
1574   return c;
1575}
1576
1577
1578
1579void XMesaDestroyContext( XMesaContext c )
1580{
1581   GLcontext *mesaCtx = &c->mesa;
1582#ifdef FX
1583   XMesaBuffer xmbuf = XMESA_BUFFER(mesaCtx->DrawBuffer);
1584
1585   if (xmbuf && xmbuf->FXctx)
1586      fxMesaDestroyContext(xmbuf->FXctx);
1587#endif
1588   _swsetup_DestroyContext( mesaCtx );
1589   _swrast_DestroyContext( mesaCtx );
1590   _tnl_DestroyContext( mesaCtx );
1591   _vbo_DestroyContext( mesaCtx );
1592   _mesa_free_context_data( mesaCtx );
1593   _mesa_free( c );
1594}
1595
1596
1597
1598/**
1599 * Private function for creating an XMesaBuffer which corresponds to an
1600 * X window or pixmap.
1601 * \param v  the window's XMesaVisual
1602 * \param w  the window we're wrapping
1603 * \param c  context used to initialize the buffer if 3Dfx mode in use.
1604 * \return  new XMesaBuffer or NULL if error
1605 */
1606XMesaBuffer
1607XMesaCreateWindowBuffer2(XMesaVisual v, XMesaWindow w, XMesaContext c)
1608{
1609#ifndef XFree86Server
1610   XWindowAttributes attr;
1611#endif
1612#ifdef FX
1613   char *fxEnvVar;
1614#endif
1615   int client = 0;
1616   XMesaBuffer b;
1617   XMesaColormap cmap;
1618
1619   assert(v);
1620   assert(w);
1621   (void) c;
1622
1623   /* Check that window depth matches visual depth */
1624#ifdef XFree86Server
1625   client = CLIENT_ID(((XMesaDrawable)w)->id);
1626
1627   if (GET_VISUAL_DEPTH(v) != ((XMesaDrawable)w)->depth) {
1628      _mesa_warning(NULL, "XMesaCreateWindowBuffer: depth mismatch between visual (%d) and window (%d)!\n",
1629                    GET_VISUAL_DEPTH(v), ((XMesaDrawable) w)->depth);
1630      return NULL;
1631   }
1632#else
1633   XGetWindowAttributes( v->display, w, &attr );
1634
1635   if (GET_VISUAL_DEPTH(v) != attr.depth) {
1636      _mesa_warning(NULL, "XMesaCreateWindowBuffer: depth mismatch between visual (%d) and window (%d)!\n",
1637                    GET_VISUAL_DEPTH(v), attr.depth);
1638      return NULL;
1639   }
1640#endif
1641
1642   /* Find colormap */
1643#ifdef XFree86Server
1644   cmap = (ColormapPtr)LookupIDByType(wColormap(w), RT_COLORMAP);
1645#else
1646   if (attr.colormap) {
1647      cmap = attr.colormap;
1648   }
1649   else {
1650      _mesa_warning(NULL, "Window %u has no colormap!\n", (unsigned int) w);
1651      /* this is weird, a window w/out a colormap!? */
1652      /* OK, let's just allocate a new one and hope for the best */
1653      cmap = XCreateColormap(v->display, w, attr.visual, AllocNone);
1654   }
1655#endif
1656
1657   b = create_xmesa_buffer((XMesaDrawable) w, WINDOW, v, cmap);
1658   if (!b)
1659      return NULL;
1660
1661   if (!initialize_visual_and_buffer( client, v, b, v->mesa_visual.rgbMode,
1662                                      (XMesaDrawable) w, cmap )) {
1663      xmesa_free_buffer(b);
1664      return NULL;
1665   }
1666
1667#ifdef FX
1668   fxEnvVar = _mesa_getenv("MESA_GLX_FX");
1669   if (fxEnvVar) {
1670     if (fxEnvVar[0]!='d') {
1671       int attribs[100];
1672       int numAttribs = 0;
1673       int hw;
1674       if (v->mesa_visual.depthBits > 0) {
1675	 attribs[numAttribs++] = FXMESA_DEPTH_SIZE;
1676	 attribs[numAttribs++] = v->mesa_visual.depthBits;
1677       }
1678       if (v->mesa_visual.doubleBufferMode) {
1679	 attribs[numAttribs++] = FXMESA_DOUBLEBUFFER;
1680       }
1681       if (v->mesa_visual.accumRedBits > 0) {
1682	 attribs[numAttribs++] = FXMESA_ACCUM_SIZE;
1683	 attribs[numAttribs++] = v->mesa_visual.accumRedBits;
1684       }
1685       if (v->mesa_visual.stencilBits > 0) {
1686         attribs[numAttribs++] = FXMESA_STENCIL_SIZE;
1687         attribs[numAttribs++] = v->mesa_visual.stencilBits;
1688       }
1689       if (v->mesa_visual.alphaBits > 0) {
1690         attribs[numAttribs++] = FXMESA_ALPHA_SIZE;
1691         attribs[numAttribs++] = v->mesa_visual.alphaBits;
1692       }
1693       if (1) {
1694         attribs[numAttribs++] = FXMESA_SHARE_CONTEXT;
1695         attribs[numAttribs++] = (int) &(c->mesa);
1696       }
1697       attribs[numAttribs++] = FXMESA_NONE;
1698
1699       /* [dBorca] we should take an envvar for `fxMesaSelectCurrentBoard'!!! */
1700       hw = fxMesaSelectCurrentBoard(0);
1701
1702       /* if these fail, there's a new bug somewhere */
1703       ASSERT(b->mesa_buffer.Width > 0);
1704       ASSERT(b->mesa_buffer.Height > 0);
1705
1706       if ((hw == GR_SSTTYPE_VOODOO) || (hw == GR_SSTTYPE_Voodoo2)) {
1707         b->FXctx = fxMesaCreateBestContext(0, b->mesa_buffer.Width,
1708                                            b->mesa_buffer.Height, attribs);
1709         if ((v->undithered_pf!=PF_Index) && (b->backxrb->ximage)) {
1710	   b->FXisHackUsable = b->FXctx ? GL_TRUE : GL_FALSE;
1711	   if (b->FXctx && (fxEnvVar[0]=='w' || fxEnvVar[0]=='W')) {
1712	     b->FXwindowHack = GL_TRUE;
1713	     FX_grSstControl(GR_CONTROL_DEACTIVATE);
1714	   }
1715           else {
1716	     b->FXwindowHack = GL_FALSE;
1717	   }
1718         }
1719       }
1720       else {
1721         if (fxEnvVar[0]=='w' || fxEnvVar[0]=='W')
1722	   b->FXctx = fxMesaCreateContext(w, GR_RESOLUTION_NONE,
1723					  GR_REFRESH_75Hz, attribs);
1724         else
1725	   b->FXctx = fxMesaCreateBestContext(0, b->mesa_buffer.Width,
1726                                              b->mesa_buffer.Height, attribs);
1727         b->FXisHackUsable = GL_FALSE;
1728         b->FXwindowHack = GL_FALSE;
1729       }
1730       /*
1731       fprintf(stderr,
1732               "voodoo %d, wid %d height %d hack: usable %d active %d\n",
1733               hw, b->mesa_buffer.Width, b->mesa_buffer.Height,
1734	       b->FXisHackUsable, b->FXwindowHack);
1735       */
1736     }
1737   }
1738   else {
1739      _mesa_warning(NULL, "WARNING: This Mesa Library includes the Glide driver but\n");
1740      _mesa_warning(NULL, "         you have not defined the MESA_GLX_FX env. var.\n");
1741      _mesa_warning(NULL, "         (check the README.3DFX file for more information).\n\n");
1742      _mesa_warning(NULL, "         you can disable this message with a 'export MESA_GLX_FX=disable'.\n");
1743   }
1744#endif
1745
1746   return b;
1747}
1748
1749
1750XMesaBuffer
1751XMesaCreateWindowBuffer(XMesaVisual v, XMesaWindow w)
1752{
1753   return XMesaCreateWindowBuffer2( v, w, NULL );
1754}
1755
1756
1757/**
1758 * Create a new XMesaBuffer from an X pixmap.
1759 *
1760 * \param v    the XMesaVisual
1761 * \param p    the pixmap
1762 * \param cmap the colormap, may be 0 if using a \c GLX_TRUE_COLOR or
1763 *             \c GLX_DIRECT_COLOR visual for the pixmap
1764 * \returns new XMesaBuffer or NULL if error
1765 */
1766XMesaBuffer
1767XMesaCreatePixmapBuffer(XMesaVisual v, XMesaPixmap p, XMesaColormap cmap)
1768{
1769   int client = 0;
1770   XMesaBuffer b;
1771
1772   assert(v);
1773
1774   b = create_xmesa_buffer((XMesaDrawable) p, PIXMAP, v, cmap);
1775   if (!b)
1776      return NULL;
1777
1778#ifdef XFree86Server
1779   client = CLIENT_ID(((XMesaDrawable)p)->id);
1780#endif
1781
1782   if (!initialize_visual_and_buffer(client, v, b, v->mesa_visual.rgbMode,
1783				     (XMesaDrawable) p, cmap)) {
1784      xmesa_free_buffer(b);
1785      return NULL;
1786   }
1787
1788   return b;
1789}
1790
1791
1792
1793XMesaBuffer
1794XMesaCreatePBuffer(XMesaVisual v, XMesaColormap cmap,
1795                   unsigned int width, unsigned int height)
1796{
1797#ifdef XFree86Server
1798   return 0;
1799#else
1800   int client = 0;
1801   XMesaWindow root;
1802   XMesaDrawable drawable;  /* X Pixmap Drawable */
1803   XMesaBuffer b;
1804
1805   /* allocate pixmap for front buffer */
1806   root = RootWindow( v->display, v->visinfo->screen );
1807   drawable = XCreatePixmap(v->display, root, width, height,
1808                            v->visinfo->depth);
1809   if (!drawable)
1810      return NULL;
1811
1812   b = create_xmesa_buffer(drawable, PBUFFER, v, cmap);
1813   if (!b)
1814      return NULL;
1815
1816   if (!initialize_visual_and_buffer(client, v, b, v->mesa_visual.rgbMode,
1817				     drawable, cmap)) {
1818      xmesa_free_buffer(b);
1819      return NULL;
1820   }
1821
1822   return b;
1823#endif
1824}
1825
1826
1827
1828/*
1829 * Deallocate an XMesaBuffer structure and all related info.
1830 */
1831void
1832XMesaDestroyBuffer(XMesaBuffer b)
1833{
1834   xmesa_free_buffer(b);
1835}
1836
1837
1838/**
1839 * Query the current window size and update the corresponding GLframebuffer
1840 * and all attached renderbuffers.
1841 * Called when:
1842 *  1. the first time a buffer is bound to a context.
1843 *  2. from glViewport to poll for window size changes
1844 *  3. from the XMesaResizeBuffers() API function.
1845 */
1846void
1847xmesa_check_and_update_buffer_size(XMesaContext xmctx, XMesaBuffer drawBuffer)
1848{
1849   GLuint width, height;
1850   xmesa_get_window_size(xmctx->display, drawBuffer, &width, &height);
1851   if (drawBuffer->mesa_buffer.Width != width ||
1852       drawBuffer->mesa_buffer.Height != height) {
1853      _mesa_resize_framebuffer(&(xmctx->mesa),
1854                               &(drawBuffer->mesa_buffer), width, height);
1855   }
1856   drawBuffer->mesa_buffer.Initialized = GL_TRUE; /* XXX TEMPORARY? */
1857}
1858
1859
1860/*
1861 * Bind buffer b to context c and make c the current rendering context.
1862 */
1863GLboolean XMesaMakeCurrent( XMesaContext c, XMesaBuffer b )
1864{
1865   return XMesaMakeCurrent2( c, b, b );
1866}
1867
1868
1869/*
1870 * Bind buffer b to context c and make c the current rendering context.
1871 */
1872GLboolean XMesaMakeCurrent2( XMesaContext c, XMesaBuffer drawBuffer,
1873                             XMesaBuffer readBuffer )
1874{
1875   if (c) {
1876      if (!drawBuffer || !readBuffer)
1877         return GL_FALSE;  /* must specify buffers! */
1878
1879#ifdef FX
1880      if (drawBuffer->FXctx) {
1881         fxMesaMakeCurrent(drawBuffer->FXctx);
1882
1883         c->xm_buffer = drawBuffer;
1884
1885         return GL_TRUE;
1886      }
1887#endif
1888      if (&(c->mesa) == _mesa_get_current_context()
1889          && c->mesa.DrawBuffer == &drawBuffer->mesa_buffer
1890          && c->mesa.ReadBuffer == &readBuffer->mesa_buffer
1891          && XMESA_BUFFER(c->mesa.DrawBuffer)->wasCurrent) {
1892         /* same context and buffer, do nothing */
1893         return GL_TRUE;
1894      }
1895
1896      c->xm_buffer = drawBuffer;
1897
1898      /* Call this periodically to detect when the user has begun using
1899       * GL rendering from multiple threads.
1900       */
1901      _glapi_check_multithread();
1902
1903      xmesa_check_and_update_buffer_size(c, drawBuffer);
1904      if (readBuffer != drawBuffer)
1905         xmesa_check_and_update_buffer_size(c, readBuffer);
1906
1907      _mesa_make_current(&(c->mesa),
1908                         &drawBuffer->mesa_buffer,
1909                         &readBuffer->mesa_buffer);
1910
1911      if (c->xm_visual->mesa_visual.rgbMode) {
1912         /*
1913          * Must recompute and set these pixel values because colormap
1914          * can be different for different windows.
1915          */
1916         c->clearpixel = xmesa_color_to_pixel( &c->mesa,
1917                                               c->clearcolor[0],
1918                                               c->clearcolor[1],
1919                                               c->clearcolor[2],
1920                                               c->clearcolor[3],
1921                                               c->xm_visual->undithered_pf);
1922         XMesaSetForeground(c->display, drawBuffer->cleargc, c->clearpixel);
1923      }
1924
1925      /* Solution to Stephane Rehel's problem with glXReleaseBuffersMESA(): */
1926      drawBuffer->wasCurrent = GL_TRUE;
1927   }
1928   else {
1929      /* Detach */
1930      _mesa_make_current( NULL, NULL, NULL );
1931   }
1932   return GL_TRUE;
1933}
1934
1935
1936/*
1937 * Unbind the context c from its buffer.
1938 */
1939GLboolean XMesaUnbindContext( XMesaContext c )
1940{
1941   /* A no-op for XFree86 integration purposes */
1942   return GL_TRUE;
1943}
1944
1945
1946XMesaContext XMesaGetCurrentContext( void )
1947{
1948   GET_CURRENT_CONTEXT(ctx);
1949   if (ctx) {
1950      XMesaContext xmesa = XMESA_CONTEXT(ctx);
1951      return xmesa;
1952   }
1953   else {
1954      return 0;
1955   }
1956}
1957
1958
1959XMesaBuffer XMesaGetCurrentBuffer( void )
1960{
1961   GET_CURRENT_CONTEXT(ctx);
1962   if (ctx) {
1963      XMesaBuffer xmbuf = XMESA_BUFFER(ctx->DrawBuffer);
1964      return xmbuf;
1965   }
1966   else {
1967      return 0;
1968   }
1969}
1970
1971
1972/* New in Mesa 3.1 */
1973XMesaBuffer XMesaGetCurrentReadBuffer( void )
1974{
1975   GET_CURRENT_CONTEXT(ctx);
1976   if (ctx) {
1977      return XMESA_BUFFER(ctx->ReadBuffer);
1978   }
1979   else {
1980      return 0;
1981   }
1982}
1983
1984
1985GLboolean XMesaForceCurrent(XMesaContext c)
1986{
1987   if (c) {
1988      if (&(c->mesa) != _mesa_get_current_context()) {
1989	 _mesa_make_current(&c->mesa, c->mesa.DrawBuffer, c->mesa.ReadBuffer);
1990      }
1991   }
1992   else {
1993      _mesa_make_current(NULL, NULL, NULL);
1994   }
1995   return GL_TRUE;
1996}
1997
1998
1999GLboolean XMesaLoseCurrent(XMesaContext c)
2000{
2001   (void) c;
2002   _mesa_make_current(NULL, NULL, NULL);
2003   return GL_TRUE;
2004}
2005
2006
2007/*
2008 * Switch 3Dfx support hack between window and full-screen mode.
2009 */
2010GLboolean XMesaSetFXmode( GLint mode )
2011{
2012#ifdef FX
2013   const char *fx = _mesa_getenv("MESA_GLX_FX");
2014   if (fx && fx[0] != 'd') {
2015      GET_CURRENT_CONTEXT(ctx);
2016      GrHwConfiguration hw;
2017      if (!FX_grSstQueryHardware(&hw)) {
2018         /*fprintf(stderr, "!grSstQueryHardware\n");*/
2019         return GL_FALSE;
2020      }
2021      if (hw.num_sst < 1) {
2022         /*fprintf(stderr, "hw.num_sst < 1\n");*/
2023         return GL_FALSE;
2024      }
2025      if (ctx) {
2026         /* [dBorca] Hack alert:
2027	  * oh, this is sooo wrong: ctx above is
2028	  * really an fxMesaContext, not an XMesaContext
2029	  */
2030         XMesaBuffer xmbuf = XMESA_BUFFER(ctx->DrawBuffer);
2031         if (mode == XMESA_FX_WINDOW) {
2032	    if (xmbuf->FXisHackUsable) {
2033	       FX_grSstControl(GR_CONTROL_DEACTIVATE);
2034	       xmbuf->FXwindowHack = GL_TRUE;
2035	       return GL_TRUE;
2036	    }
2037	 }
2038	 else if (mode == XMESA_FX_FULLSCREEN) {
2039	    FX_grSstControl(GR_CONTROL_ACTIVATE);
2040	    xmbuf->FXwindowHack = GL_FALSE;
2041	    return GL_TRUE;
2042	 }
2043	 else {
2044	    /* Error: Bad mode value */
2045	 }
2046      }
2047   }
2048   /*fprintf(stderr, "fallthrough\n");*/
2049#else
2050   (void) mode;
2051#endif
2052   return GL_FALSE;
2053}
2054
2055
2056
2057#ifdef FX
2058/*
2059 * Read image from VooDoo frame buffer into X/Mesa's back XImage.
2060 */
2061static void FXgetImage( XMesaBuffer b )
2062{
2063   GET_CURRENT_CONTEXT(ctx);
2064   static unsigned short pixbuf[MAX_WIDTH];
2065   GLuint x, y;
2066   GLuint width, height;
2067   XMesaContext xmesa = XMESA_CONTEXT(ctx);
2068
2069#ifdef XFree86Server
2070   x = b->frontxrb->pixmap->x;
2071   y = b->frontxrb->pixmap->y;
2072   width = b->frontxrb->pixmap->width;
2073   height = b->frontxrb->pixmap->height;
2074   depth = b->frontxrb->pixmap->depth;
2075#else
2076   xmesa_get_window_size(b->display, b, &width, &height);
2077   x = y = 0;
2078#endif
2079   if (b->mesa_buffer.Width != width || b->mesa_buffer.Height != height) {
2080      b->mesa_buffer.Width = MIN2((int)width, b->FXctx->width);
2081      b->mesa_buffer.Height = MIN2((int)height, b->FXctx->height);
2082      if (b->mesa_buffer.Width & 1)
2083         b->mesa_buffer.Width--;  /* prevent odd width */
2084   }
2085
2086   /* [dBorca] we're always in the right GR_COLORFORMAT... aren't we? */
2087   /* grLfbWriteColorFormat(GR_COLORFORMAT_ARGB); */
2088   if (b->xm_visual->undithered_pf==PF_5R6G5B) {
2089      /* Special case: 16bpp RGB */
2090      grLfbReadRegion( GR_BUFFER_FRONTBUFFER,       /* src buffer */
2091                       0, b->FXctx->height - b->mesa_buffer.Height,  /*pos*/
2092                       b->mesa_buffer.Width, b->mesa_buffer.Height,  /* size */
2093                       b->mesa_buffer.Width * sizeof(GLushort), /* stride */
2094                       b->backxrb->ximage->data);         /* dest buffer */
2095   }
2096   else if (b->xm_visual->dithered_pf==PF_Dither
2097	    && GET_VISUAL_DEPTH(b->xm_visual)==8) {
2098      /* Special case: 8bpp RGB */
2099      for (y=0;y<b->mesa_buffer.Height;y++) {
2100         GLubyte *ptr = (GLubyte*) b->backxrb->ximage->data
2101                        + b->backxrb->ximage->bytes_per_line * y;
2102         XDITHER_SETUP(y);
2103
2104         /* read row from 3Dfx frame buffer */
2105         grLfbReadRegion( GR_BUFFER_FRONTBUFFER,
2106                          0, b->FXctx->height-(b->mesa_buffer.Height-y),
2107                          b->mesa_buffer.Width, 1,
2108                          0,
2109                          pixbuf );
2110
2111         /* write to XImage back buffer */
2112         for (x=0;x<b->mesa_buffer.Width;x++) {
2113            GLubyte r = (pixbuf[x] & 0xf800) >> 8;
2114            GLubyte g = (pixbuf[x] & 0x07e0) >> 3;
2115            GLubyte b = (pixbuf[x] & 0x001f) << 3;
2116            *ptr++ = XDITHER( x, r, g, b);
2117         }
2118      }
2119   }
2120   else {
2121      /* General case: slow! */
2122      for (y=0;y<b->mesa_buffer.Height;y++) {
2123         /* read row from 3Dfx frame buffer */
2124         grLfbReadRegion( GR_BUFFER_FRONTBUFFER,
2125                          0, b->FXctx->height-(b->mesa_buffer.Height-y),
2126                          b->mesa_buffer.Width, 1,
2127                          0,
2128                          pixbuf );
2129
2130         /* write to XImage back buffer */
2131         for (x=0;x<b->mesa_buffer.Width;x++) {
2132            XMesaPutPixel(b->backxrb->ximage,x,y,
2133			  xmesa_color_to_pixel(ctx,
2134					       (pixbuf[x] & 0xf800) >> 8,
2135					       (pixbuf[x] & 0x07e0) >> 3,
2136					       (pixbuf[x] & 0x001f) << 3,
2137					       0xff,
2138                                               b->xm_visual->undithered_pf));
2139         }
2140      }
2141   }
2142   /* grLfbWriteColorFormat(GR_COLORFORMAT_ABGR); */
2143}
2144#endif
2145
2146
2147/*
2148 * Copy the back buffer to the front buffer.  If there's no back buffer
2149 * this is a no-op.
2150 */
2151void XMesaSwapBuffers( XMesaBuffer b )
2152{
2153   GET_CURRENT_CONTEXT(ctx);
2154
2155   if (!b->backxrb) {
2156      /* single buffered */
2157      return;
2158   }
2159
2160   /* If we're swapping the buffer associated with the current context
2161    * we have to flush any pending rendering commands first.
2162    */
2163   if (ctx && ctx->DrawBuffer == &(b->mesa_buffer))
2164      _mesa_notifySwapBuffers(ctx);
2165
2166   if (b->db_mode) {
2167#ifdef FX
2168      if (b->FXctx) {
2169         fxMesaSwapBuffers();
2170
2171         if (b->FXwindowHack)
2172            FXgetImage(b);
2173         else
2174            return;
2175      }
2176#endif
2177     if (b->backxrb->ximage) {
2178	 /* Copy Ximage from host's memory to server's window */
2179#if defined(USE_XSHM) && !defined(XFree86Server)
2180	 if (b->shm) {
2181            /*_glthread_LOCK_MUTEX(_xmesa_lock);*/
2182	    XShmPutImage( b->xm_visual->display, b->frontxrb->drawable,
2183			  b->swapgc,
2184			  b->backxrb->ximage, 0, 0,
2185			  0, 0, b->mesa_buffer.Width, b->mesa_buffer.Height,
2186                          False );
2187            /*_glthread_UNLOCK_MUTEX(_xmesa_lock);*/
2188	 }
2189	 else
2190#endif
2191         {
2192            /*_glthread_LOCK_MUTEX(_xmesa_lock);*/
2193            XMesaPutImage( b->xm_visual->display, b->frontxrb->drawable,
2194			   b->swapgc,
2195			   b->backxrb->ximage, 0, 0,
2196			   0, 0, b->mesa_buffer.Width, b->mesa_buffer.Height );
2197            /*_glthread_UNLOCK_MUTEX(_xmesa_lock);*/
2198         }
2199      }
2200      else {
2201	 /* Copy pixmap to window on server */
2202         /*_glthread_LOCK_MUTEX(_xmesa_lock);*/
2203	 XMesaCopyArea( b->xm_visual->display,
2204			b->backxrb->pixmap,   /* source drawable */
2205			b->frontxrb->drawable,  /* dest. drawable */
2206			b->swapgc,
2207			0, 0, b->mesa_buffer.Width, b->mesa_buffer.Height,
2208			0, 0                 /* dest region */
2209		      );
2210         /*_glthread_UNLOCK_MUTEX(_xmesa_lock);*/
2211      }
2212   }
2213#if !defined(XFree86Server)
2214   XSync( b->xm_visual->display, False );
2215#endif
2216}
2217
2218
2219
2220/*
2221 * Copy sub-region of back buffer to front buffer
2222 */
2223void XMesaCopySubBuffer( XMesaBuffer b, int x, int y, int width, int height )
2224{
2225   GET_CURRENT_CONTEXT(ctx);
2226
2227   /* If we're swapping the buffer associated with the current context
2228    * we have to flush any pending rendering commands first.
2229    */
2230   if (ctx && ctx->DrawBuffer == &(b->mesa_buffer))
2231      _mesa_notifySwapBuffers(ctx);
2232
2233   if (!b->backxrb) {
2234      /* single buffered */
2235      return;
2236   }
2237
2238   if (b->db_mode) {
2239      int yTop = b->mesa_buffer.Height - y - height;
2240#ifdef FX
2241      if (b->FXctx) {
2242         fxMesaSwapBuffers();
2243         if (b->FXwindowHack)
2244            FXgetImage(b);
2245         else
2246            return;
2247      }
2248#endif
2249      if (b->backxrb->ximage) {
2250         /* Copy Ximage from host's memory to server's window */
2251#if defined(USE_XSHM) && !defined(XFree86Server)
2252         if (b->shm) {
2253            /* XXX assuming width and height aren't too large! */
2254            XShmPutImage( b->xm_visual->display, b->frontxrb->drawable,
2255                          b->swapgc,
2256                          b->backxrb->ximage, x, yTop,
2257                          x, yTop, width, height, False );
2258            /* wait for finished event??? */
2259         }
2260         else
2261#endif
2262         {
2263            /* XXX assuming width and height aren't too large! */
2264            XMesaPutImage( b->xm_visual->display, b->frontxrb->drawable,
2265			   b->swapgc,
2266			   b->backxrb->ximage, x, yTop,
2267			   x, yTop, width, height );
2268         }
2269      }
2270      else {
2271         /* Copy pixmap to window on server */
2272         XMesaCopyArea( b->xm_visual->display,
2273			b->backxrb->pixmap,           /* source drawable */
2274			b->frontxrb->drawable,        /* dest. drawable */
2275			b->swapgc,
2276			x, yTop, width, height,  /* source region */
2277			x, yTop                  /* dest region */
2278                      );
2279      }
2280   }
2281}
2282
2283
2284/*
2285 * Return a pointer to the XMesa backbuffer Pixmap or XImage.  This function
2286 * is a way to get "under the hood" of X/Mesa so one can manipulate the
2287 * back buffer directly.
2288 * Output:  pixmap - pointer to back buffer's Pixmap, or 0
2289 *          ximage - pointer to back buffer's XImage, or NULL
2290 * Return:  GL_TRUE = context is double buffered
2291 *          GL_FALSE = context is single buffered
2292 */
2293#ifndef XFree86Server
2294GLboolean XMesaGetBackBuffer( XMesaBuffer b,
2295                              XMesaPixmap *pixmap,
2296                              XMesaImage **ximage )
2297{
2298   if (b->db_mode) {
2299      if (pixmap)
2300         *pixmap = b->backxrb->pixmap;
2301      if (ximage)
2302         *ximage = b->backxrb->ximage;
2303      return GL_TRUE;
2304   }
2305   else {
2306      *pixmap = 0;
2307      *ximage = NULL;
2308      return GL_FALSE;
2309   }
2310}
2311#endif /* XFree86Server */
2312
2313
2314/*
2315 * Return the depth buffer associated with an XMesaBuffer.
2316 * Input:  b - the XMesa buffer handle
2317 * Output:  width, height - size of buffer in pixels
2318 *          bytesPerValue - bytes per depth value (2 or 4)
2319 *          buffer - pointer to depth buffer values
2320 * Return:  GL_TRUE or GL_FALSE to indicate success or failure.
2321 */
2322GLboolean XMesaGetDepthBuffer( XMesaBuffer b, GLint *width, GLint *height,
2323                               GLint *bytesPerValue, void **buffer )
2324{
2325   struct gl_renderbuffer *rb
2326      = b->mesa_buffer.Attachment[BUFFER_DEPTH].Renderbuffer;
2327   if (!rb || !rb->Data) {
2328      *width = 0;
2329      *height = 0;
2330      *bytesPerValue = 0;
2331      *buffer = 0;
2332      return GL_FALSE;
2333   }
2334   else {
2335      *width = b->mesa_buffer.Width;
2336      *height = b->mesa_buffer.Height;
2337      *bytesPerValue = b->mesa_buffer.Visual.depthBits <= 16
2338         ? sizeof(GLushort) : sizeof(GLuint);
2339      *buffer = rb->Data;
2340      return GL_TRUE;
2341   }
2342}
2343
2344
2345void XMesaFlush( XMesaContext c )
2346{
2347   if (c && c->xm_visual) {
2348#ifdef XFree86Server
2349      /* NOT_NEEDED */
2350#else
2351      XSync( c->xm_visual->display, False );
2352#endif
2353   }
2354}
2355
2356
2357
2358const char *XMesaGetString( XMesaContext c, int name )
2359{
2360   (void) c;
2361   if (name==XMESA_VERSION) {
2362      return "5.0";
2363   }
2364   else if (name==XMESA_EXTENSIONS) {
2365      return "";
2366   }
2367   else {
2368      return NULL;
2369   }
2370}
2371
2372
2373
2374XMesaBuffer XMesaFindBuffer( XMesaDisplay *dpy, XMesaDrawable d )
2375{
2376   XMesaBuffer b;
2377   for (b=XMesaBufferList; b; b=b->Next) {
2378      if (b->frontxrb->drawable == d && b->display == dpy) {
2379         return b;
2380      }
2381   }
2382   return NULL;
2383}
2384
2385
2386/**
2387 * Free/destroy all XMesaBuffers associated with given display.
2388 */
2389void xmesa_destroy_buffers_on_display(XMesaDisplay *dpy)
2390{
2391   XMesaBuffer b, next;
2392   for (b = XMesaBufferList; b; b = next) {
2393      next = b->Next;
2394      if (b->display == dpy) {
2395         xmesa_free_buffer(b);
2396      }
2397   }
2398}
2399
2400
2401/*
2402 * Look for XMesaBuffers whose X window has been destroyed.
2403 * Deallocate any such XMesaBuffers.
2404 */
2405void XMesaGarbageCollect( void )
2406{
2407   XMesaBuffer b, next;
2408   for (b=XMesaBufferList; b; b=next) {
2409      next = b->Next;
2410      if (b->display && b->frontxrb->drawable && b->type == WINDOW) {
2411#ifdef XFree86Server
2412	 /* NOT_NEEDED */
2413#else
2414         XSync(b->display, False);
2415         if (!window_exists( b->display, b->frontxrb->drawable )) {
2416            /* found a dead window, free the ancillary info */
2417            XMesaDestroyBuffer( b );
2418         }
2419#endif
2420      }
2421   }
2422}
2423
2424
2425void XMesaReset( void )
2426{
2427    while (XMesaBufferList)
2428	XMesaDestroyBuffer(XMesaBufferList);
2429
2430    XMesaBufferList = NULL;
2431}
2432
2433
2434unsigned long XMesaDitherColor( XMesaContext xmesa, GLint x, GLint y,
2435                                GLfloat red, GLfloat green,
2436                                GLfloat blue, GLfloat alpha )
2437{
2438   GLcontext *ctx = &xmesa->mesa;
2439   GLint r = (GLint) (red   * 255.0F);
2440   GLint g = (GLint) (green * 255.0F);
2441   GLint b = (GLint) (blue  * 255.0F);
2442   GLint a = (GLint) (alpha * 255.0F);
2443
2444   switch (xmesa->pixelformat) {
2445      case PF_Index:
2446         return 0;
2447      case PF_Truecolor:
2448         {
2449            unsigned long p;
2450            PACK_TRUECOLOR( p, r, g, b );
2451            return p;
2452         }
2453      case PF_8A8B8G8R:
2454         return PACK_8A8B8G8R( r, g, b, a );
2455      case PF_8A8R8G8B:
2456         return PACK_8A8R8G8B( r, g, b, a );
2457      case PF_8R8G8B:
2458         return PACK_8R8G8B( r, g, b );
2459      case PF_5R6G5B:
2460         return PACK_5R6G5B( r, g, b );
2461      case PF_Dither:
2462         {
2463            DITHER_SETUP;
2464            return DITHER( x, y, r, g, b );
2465         }
2466      case PF_1Bit:
2467         /* 382 = (3*255)/2 */
2468         return ((r+g+b) > 382) ^ xmesa->xm_visual->bitFlip;
2469      case PF_HPCR:
2470         return DITHER_HPCR(x, y, r, g, b);
2471      case PF_Lookup:
2472         {
2473            LOOKUP_SETUP;
2474            return LOOKUP( r, g, b );
2475         }
2476      case PF_Grayscale:
2477         return GRAY_RGB( r, g, b );
2478      case PF_Dither_5R6G5B:
2479         /* fall through */
2480      case PF_Dither_True:
2481         {
2482            unsigned long p;
2483            PACK_TRUEDITHER(p, x, y, r, g, b);
2484            return p;
2485         }
2486      default:
2487         _mesa_problem(NULL, "Bad pixel format in XMesaDitherColor");
2488   }
2489   return 0;
2490}
2491
2492
2493/*
2494 * This is typically called when the window size changes and we need
2495 * to reallocate the buffer's back/depth/stencil/accum buffers.
2496 */
2497void
2498XMesaResizeBuffers( XMesaBuffer b )
2499{
2500   GET_CURRENT_CONTEXT(ctx);
2501   XMesaContext xmctx = XMESA_CONTEXT(ctx);
2502   xmesa_check_and_update_buffer_size(xmctx, b);
2503}
2504
2505