xm_api.c revision 37fd6be41134df46cb9dad7f9201188ff9707629 
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         /* Unreference.  If count = zero we'll really delete the buffer */
487         _mesa_unreference_framebuffer(&fb);
488
489         return;
490      }
491      /* continue search */
492      prev = b;
493   }
494   /* buffer not found in XMesaBufferList */
495   _mesa_problem(NULL,"xmesa_free_buffer() - buffer not found\n");
496}
497
498
499/**
500 * Copy X color table stuff from one XMesaBuffer to another.
501 */
502static void
503copy_colortable_info(XMesaBuffer dst, const XMesaBuffer src)
504{
505   MEMCPY(dst->color_table, src->color_table, sizeof(src->color_table));
506   MEMCPY(dst->pixel_to_r, src->pixel_to_r, sizeof(src->pixel_to_r));
507   MEMCPY(dst->pixel_to_g, src->pixel_to_g, sizeof(src->pixel_to_g));
508   MEMCPY(dst->pixel_to_b, src->pixel_to_b, sizeof(src->pixel_to_b));
509   dst->num_alloced = src->num_alloced;
510   MEMCPY(dst->alloced_colors, src->alloced_colors,
511          sizeof(src->alloced_colors));
512}
513
514
515
516/**********************************************************************/
517/*****                   Misc Private Functions                   *****/
518/**********************************************************************/
519
520
521/**
522 * A replacement for XAllocColor.  This function should never
523 * fail to allocate a color.  When XAllocColor fails, we return
524 * the nearest matching color.  If we have to allocate many colors
525 * this function isn't too efficient; the XQueryColors() could be
526 * done just once.
527 * Written by Michael Pichler, Brian Paul, Mark Kilgard
528 * Input:  dpy - X display
529 *         cmap - X colormap
530 *         cmapSize - size of colormap
531 * In/Out: color - the XColor struct
532 * Output:  exact - 1=exact color match, 0=closest match
533 *          alloced - 1=XAlloc worked, 0=XAlloc failed
534 */
535static void
536noFaultXAllocColor( int client,
537                    XMesaDisplay *dpy,
538                    XMesaColormap cmap,
539                    int cmapSize,
540                    XMesaColor *color,
541                    int *exact, int *alloced )
542{
543#ifdef XFree86Server
544   Pixel *ppixIn;
545   xrgb *ctable;
546#else
547   /* we'll try to cache ctable for better remote display performance */
548   static Display *prevDisplay = NULL;
549   static XMesaColormap prevCmap = 0;
550   static int prevCmapSize = 0;
551   static XMesaColor *ctable = NULL;
552#endif
553   XMesaColor subColor;
554   int i, bestmatch;
555   double mindist;       /* 3*2^16^2 exceeds long int precision. */
556
557   (void) client;
558
559   /* First try just using XAllocColor. */
560#ifdef XFree86Server
561   if (AllocColor(cmap,
562		  &color->red, &color->green, &color->blue,
563		  &color->pixel,
564		  client) == Success)
565#else
566   if (XAllocColor(dpy, cmap, color))
567#endif
568   {
569      *exact = 1;
570      *alloced = 1;
571      return;
572   }
573
574   /* Alloc failed, search for closest match */
575
576   /* Retrieve color table entries. */
577   /* XXX alloca candidate. */
578#ifdef XFree86Server
579   ppixIn = (Pixel *) MALLOC(cmapSize * sizeof(Pixel));
580   ctable = (xrgb *) MALLOC(cmapSize * sizeof(xrgb));
581   for (i = 0; i < cmapSize; i++) {
582      ppixIn[i] = i;
583   }
584   QueryColors(cmap, cmapSize, ppixIn, ctable);
585#else
586   if (prevDisplay != dpy || prevCmap != cmap
587       || prevCmapSize != cmapSize || !ctable) {
588      /* free previously cached color table */
589      if (ctable)
590         _mesa_free(ctable);
591      /* Get the color table from X */
592      ctable = (XMesaColor *) MALLOC(cmapSize * sizeof(XMesaColor));
593      assert(ctable);
594      for (i = 0; i < cmapSize; i++) {
595         ctable[i].pixel = i;
596      }
597      XQueryColors(dpy, cmap, ctable, cmapSize);
598      prevDisplay = dpy;
599      prevCmap = cmap;
600      prevCmapSize = cmapSize;
601   }
602#endif
603
604   /* Find best match. */
605   bestmatch = -1;
606   mindist = 0.0;
607   for (i = 0; i < cmapSize; i++) {
608      double dr = 0.30 * ((double) color->red - (double) ctable[i].red);
609      double dg = 0.59 * ((double) color->green - (double) ctable[i].green);
610      double db = 0.11 * ((double) color->blue - (double) ctable[i].blue);
611      double dist = dr * dr + dg * dg + db * db;
612      if (bestmatch < 0 || dist < mindist) {
613         bestmatch = i;
614         mindist = dist;
615      }
616   }
617
618   /* Return result. */
619   subColor.red   = ctable[bestmatch].red;
620   subColor.green = ctable[bestmatch].green;
621   subColor.blue  = ctable[bestmatch].blue;
622   /* Try to allocate the closest match color.  This should only
623    * fail if the cell is read/write.  Otherwise, we're incrementing
624    * the cell's reference count.
625    */
626#ifdef XFree86Server
627   if (AllocColor(cmap,
628		  &subColor.red, &subColor.green, &subColor.blue,
629		  &subColor.pixel,
630		  client) == Success) {
631#else
632   if (XAllocColor(dpy, cmap, &subColor)) {
633#endif
634      *alloced = 1;
635   }
636   else {
637      /* do this to work around a problem reported by Frank Ortega */
638      subColor.pixel = (unsigned long) bestmatch;
639      subColor.red   = ctable[bestmatch].red;
640      subColor.green = ctable[bestmatch].green;
641      subColor.blue  = ctable[bestmatch].blue;
642      subColor.flags = DoRed | DoGreen | DoBlue;
643      *alloced = 0;
644   }
645#ifdef XFree86Server
646   _mesa_free(ppixIn);
647   _mesa_free(ctable);
648#else
649   /* don't free table, save it for next time */
650#endif
651
652   *color = subColor;
653   *exact = 0;
654}
655
656
657
658/**
659 * Do setup for PF_GRAYSCALE pixel format.
660 * Note that buffer may be NULL.
661 */
662static GLboolean
663setup_grayscale(int client, XMesaVisual v,
664                XMesaBuffer buffer, XMesaColormap cmap)
665{
666   if (GET_VISUAL_DEPTH(v)<4 || GET_VISUAL_DEPTH(v)>16) {
667      return GL_FALSE;
668   }
669
670   if (buffer) {
671      XMesaBuffer prevBuffer;
672
673      if (!cmap) {
674         return GL_FALSE;
675      }
676
677      prevBuffer = xmesa_find_buffer(v->display, cmap, buffer);
678      if (prevBuffer &&
679          (buffer->xm_visual->mesa_visual.rgbMode ==
680           prevBuffer->xm_visual->mesa_visual.rgbMode)) {
681         /* Copy colormap stuff from previous XMesaBuffer which uses same
682          * X colormap.  Do this to avoid time spent in noFaultXAllocColor.
683          */
684         copy_colortable_info(buffer, prevBuffer);
685      }
686      else {
687         /* Allocate 256 shades of gray */
688         int gray;
689         int colorsfailed = 0;
690         for (gray=0;gray<256;gray++) {
691            GLint r = gamma_adjust( v->RedGamma,   gray, 255 );
692            GLint g = gamma_adjust( v->GreenGamma, gray, 255 );
693            GLint b = gamma_adjust( v->BlueGamma,  gray, 255 );
694            int exact, alloced;
695            XMesaColor xcol;
696            xcol.red   = (r << 8) | r;
697            xcol.green = (g << 8) | g;
698            xcol.blue  = (b << 8) | b;
699            noFaultXAllocColor( client, v->display,
700                                cmap, GET_COLORMAP_SIZE(v),
701                                &xcol, &exact, &alloced );
702            if (!exact) {
703               colorsfailed++;
704            }
705            if (alloced) {
706               assert(buffer->num_alloced<256);
707               buffer->alloced_colors[buffer->num_alloced] = xcol.pixel;
708               buffer->num_alloced++;
709            }
710
711            /*OLD
712            assert(gray < 576);
713            buffer->color_table[gray*3+0] = xcol.pixel;
714            buffer->color_table[gray*3+1] = xcol.pixel;
715            buffer->color_table[gray*3+2] = xcol.pixel;
716            assert(xcol.pixel < 65536);
717            buffer->pixel_to_r[xcol.pixel] = gray * 30 / 100;
718            buffer->pixel_to_g[xcol.pixel] = gray * 59 / 100;
719            buffer->pixel_to_b[xcol.pixel] = gray * 11 / 100;
720            */
721            buffer->color_table[gray] = xcol.pixel;
722            assert(xcol.pixel < 65536);
723            buffer->pixel_to_r[xcol.pixel] = gray;
724            buffer->pixel_to_g[xcol.pixel] = gray;
725            buffer->pixel_to_b[xcol.pixel] = gray;
726         }
727
728         if (colorsfailed && _mesa_getenv("MESA_DEBUG")) {
729            _mesa_warning(NULL,
730                  "Note: %d out of 256 needed colors do not match exactly.\n",
731                  colorsfailed );
732         }
733      }
734   }
735
736   v->dithered_pf = PF_Grayscale;
737   v->undithered_pf = PF_Grayscale;
738   return GL_TRUE;
739}
740
741
742
743/**
744 * Setup RGB rendering for a window with a PseudoColor, StaticColor,
745 * or 8-bit TrueColor visual visual.  We try to allocate a palette of 225
746 * colors (5 red, 9 green, 5 blue) and dither to approximate a 24-bit RGB
747 * color.  While this function was originally designed just for 8-bit
748 * visuals, it has also proven to work from 4-bit up to 16-bit visuals.
749 * Dithering code contributed by Bob Mercier.
750 */
751static GLboolean
752setup_dithered_color(int client, XMesaVisual v,
753                     XMesaBuffer buffer, XMesaColormap cmap)
754{
755   if (GET_VISUAL_DEPTH(v)<4 || GET_VISUAL_DEPTH(v)>16) {
756      return GL_FALSE;
757   }
758
759   if (buffer) {
760      XMesaBuffer prevBuffer;
761
762      if (!cmap) {
763         return GL_FALSE;
764      }
765
766      prevBuffer = xmesa_find_buffer(v->display, cmap, buffer);
767      if (prevBuffer &&
768          (buffer->xm_visual->mesa_visual.rgbMode ==
769           prevBuffer->xm_visual->mesa_visual.rgbMode)) {
770         /* Copy colormap stuff from previous, matching XMesaBuffer.
771          * Do this to avoid time spent in noFaultXAllocColor.
772          */
773         copy_colortable_info(buffer, prevBuffer);
774      }
775      else {
776         /* Allocate X colors and initialize color_table[], red_table[], etc */
777         int r, g, b, i;
778         int colorsfailed = 0;
779         for (r = 0; r < DITH_R; r++) {
780            for (g = 0; g < DITH_G; g++) {
781               for (b = 0; b < DITH_B; b++) {
782                  XMesaColor xcol;
783                  int exact, alloced;
784                  xcol.red  =gamma_adjust(v->RedGamma,   r*65535/(DITH_R-1),65535);
785                  xcol.green=gamma_adjust(v->GreenGamma, g*65535/(DITH_G-1),65535);
786                  xcol.blue =gamma_adjust(v->BlueGamma,  b*65535/(DITH_B-1),65535);
787                  noFaultXAllocColor( client, v->display,
788                                      cmap, GET_COLORMAP_SIZE(v),
789                                      &xcol, &exact, &alloced );
790                  if (!exact) {
791                     colorsfailed++;
792                  }
793                  if (alloced) {
794                     assert(buffer->num_alloced<256);
795                     buffer->alloced_colors[buffer->num_alloced] = xcol.pixel;
796                     buffer->num_alloced++;
797                  }
798                  i = DITH_MIX( r, g, b );
799                  assert(i < 576);
800                  buffer->color_table[i] = xcol.pixel;
801                  assert(xcol.pixel < 65536);
802                  buffer->pixel_to_r[xcol.pixel] = r * 255 / (DITH_R-1);
803                  buffer->pixel_to_g[xcol.pixel] = g * 255 / (DITH_G-1);
804                  buffer->pixel_to_b[xcol.pixel] = b * 255 / (DITH_B-1);
805               }
806            }
807         }
808
809         if (colorsfailed && _mesa_getenv("MESA_DEBUG")) {
810            _mesa_warning(NULL,
811                  "Note: %d out of %d needed colors do not match exactly.\n",
812                  colorsfailed, DITH_R * DITH_G * DITH_B );
813         }
814      }
815   }
816
817   v->dithered_pf = PF_Dither;
818   v->undithered_pf = PF_Lookup;
819   return GL_TRUE;
820}
821
822
823/**
824 * Setup for Hewlett Packard Color Recovery 8-bit TrueColor mode.
825 * HPCR simulates 24-bit color fidelity with an 8-bit frame buffer.
826 * Special dithering tables have to be initialized.
827 */
828static void
829setup_8bit_hpcr(XMesaVisual v)
830{
831   /* HP Color Recovery contributed by:  Alex De Bruyn (ad@lms.be)
832    * To work properly, the atom _HP_RGB_SMOOTH_MAP_LIST must be defined
833    * on the root window AND the colormap obtainable by XGetRGBColormaps
834    * for that atom must be set on the window.  (see also tkInitWindow)
835    * If that colormap is not set, the output will look stripy.
836    */
837
838   /* Setup color tables with gamma correction */
839   int i;
840   double g;
841
842   g = 1.0 / v->RedGamma;
843   for (i=0; i<256; i++) {
844      GLint red = IROUND_POS(255.0 * _mesa_pow( hpcr_rgbTbl[0][i]/255.0, g ));
845      v->hpcr_rgbTbl[0][i] = CLAMP( red, 16, 239 );
846   }
847
848   g = 1.0 / v->GreenGamma;
849   for (i=0; i<256; i++) {
850      GLint green = IROUND_POS(255.0 * _mesa_pow( hpcr_rgbTbl[1][i]/255.0, g ));
851      v->hpcr_rgbTbl[1][i] = CLAMP( green, 16, 239 );
852   }
853
854   g = 1.0 / v->BlueGamma;
855   for (i=0; i<256; i++) {
856      GLint blue = IROUND_POS(255.0 * _mesa_pow( hpcr_rgbTbl[2][i]/255.0, g ));
857      v->hpcr_rgbTbl[2][i] = CLAMP( blue, 32, 223 );
858   }
859   v->undithered_pf = PF_HPCR;  /* can't really disable dithering for now */
860   v->dithered_pf = PF_HPCR;
861
862   /* which method should I use to clear */
863   /* GL_FALSE: keep the ordinary method  */
864   /* GL_TRUE : clear with dither pattern */
865   v->hpcr_clear_flag = _mesa_getenv("MESA_HPCR_CLEAR") ? GL_TRUE : GL_FALSE;
866
867   if (v->hpcr_clear_flag) {
868      v->hpcr_clear_pixmap = XMesaCreatePixmap(v->display,
869                                               DefaultRootWindow(v->display),
870                                               16, 2, 8);
871#ifndef XFree86Server
872      v->hpcr_clear_ximage = XGetImage(v->display, v->hpcr_clear_pixmap,
873                                       0, 0, 16, 2, AllPlanes, ZPixmap);
874#endif
875   }
876}
877
878
879/**
880 * Setup RGB rendering for a window with a True/DirectColor visual.
881 */
882static void
883setup_truecolor(XMesaVisual v, XMesaBuffer buffer, XMesaColormap cmap)
884{
885   unsigned long rmask, gmask, bmask;
886   (void) buffer;
887   (void) cmap;
888
889   /* Compute red multiplier (mask) and bit shift */
890   v->rshift = 0;
891   rmask = GET_REDMASK(v);
892   while ((rmask & 1)==0) {
893      v->rshift++;
894      rmask = rmask >> 1;
895   }
896
897   /* Compute green multiplier (mask) and bit shift */
898   v->gshift = 0;
899   gmask = GET_GREENMASK(v);
900   while ((gmask & 1)==0) {
901      v->gshift++;
902      gmask = gmask >> 1;
903   }
904
905   /* Compute blue multiplier (mask) and bit shift */
906   v->bshift = 0;
907   bmask = GET_BLUEMASK(v);
908   while ((bmask & 1)==0) {
909      v->bshift++;
910      bmask = bmask >> 1;
911   }
912
913   /*
914    * Compute component-to-pixel lookup tables and dithering kernel
915    */
916   {
917      static GLubyte kernel[16] = {
918          0*16,  8*16,  2*16, 10*16,
919         12*16,  4*16, 14*16,  6*16,
920          3*16, 11*16,  1*16,  9*16,
921         15*16,  7*16, 13*16,  5*16,
922      };
923      GLint rBits = _mesa_bitcount(rmask);
924      GLint gBits = _mesa_bitcount(gmask);
925      GLint bBits = _mesa_bitcount(bmask);
926      GLint maxBits;
927      GLuint i;
928
929      /* convert pixel components in [0,_mask] to RGB values in [0,255] */
930      for (i=0; i<=rmask; i++)
931         v->PixelToR[i] = (unsigned char) ((i * 255) / rmask);
932      for (i=0; i<=gmask; i++)
933         v->PixelToG[i] = (unsigned char) ((i * 255) / gmask);
934      for (i=0; i<=bmask; i++)
935         v->PixelToB[i] = (unsigned char) ((i * 255) / bmask);
936
937      /* convert RGB values from [0,255] to pixel components */
938
939      for (i=0;i<256;i++) {
940         GLint r = gamma_adjust(v->RedGamma,   i, 255);
941         GLint g = gamma_adjust(v->GreenGamma, i, 255);
942         GLint b = gamma_adjust(v->BlueGamma,  i, 255);
943         v->RtoPixel[i] = (r >> (8-rBits)) << v->rshift;
944         v->GtoPixel[i] = (g >> (8-gBits)) << v->gshift;
945         v->BtoPixel[i] = (b >> (8-bBits)) << v->bshift;
946      }
947      /* overflow protection */
948      for (i=256;i<512;i++) {
949         v->RtoPixel[i] = v->RtoPixel[255];
950         v->GtoPixel[i] = v->GtoPixel[255];
951         v->BtoPixel[i] = v->BtoPixel[255];
952      }
953
954      /* setup dithering kernel */
955      maxBits = rBits;
956      if (gBits > maxBits)  maxBits = gBits;
957      if (bBits > maxBits)  maxBits = bBits;
958      for (i=0;i<16;i++) {
959         v->Kernel[i] = kernel[i] >> maxBits;
960      }
961
962      v->undithered_pf = PF_Truecolor;
963      v->dithered_pf = (GET_VISUAL_DEPTH(v)<24) ? PF_Dither_True : PF_Truecolor;
964   }
965
966   /*
967    * Now check for TrueColor visuals which we can optimize.
968    */
969   if (   GET_REDMASK(v)  ==0x0000ff
970       && GET_GREENMASK(v)==0x00ff00
971       && GET_BLUEMASK(v) ==0xff0000
972       && CHECK_BYTE_ORDER(v)
973       && v->BitsPerPixel==32
974       && sizeof(GLuint)==4
975       && v->RedGamma==1.0 && v->GreenGamma==1.0 && v->BlueGamma==1.0) {
976      /* common 32 bpp config used on SGI, Sun */
977      v->undithered_pf = v->dithered_pf = PF_8A8B8G8R;
978   }
979   else if (GET_REDMASK(v)  ==0xff0000
980       &&   GET_GREENMASK(v)==0x00ff00
981       &&   GET_BLUEMASK(v) ==0x0000ff
982       && CHECK_BYTE_ORDER(v)
983       && v->BitsPerPixel==32
984       && sizeof(GLuint)==4
985       && v->RedGamma==1.0 && v->GreenGamma==1.0 && v->BlueGamma==1.0) {
986      /* common 32 bpp config used on Linux, HP, IBM */
987      if (GET_VISUAL_DEPTH(v)==32)
988	  v->undithered_pf = v->dithered_pf = PF_8A8R8G8B;
989      else
990	  v->undithered_pf = v->dithered_pf = PF_8R8G8B;
991   }
992   else if (GET_REDMASK(v)  ==0xff0000
993       &&   GET_GREENMASK(v)==0x00ff00
994       &&   GET_BLUEMASK(v) ==0x0000ff
995       && CHECK_BYTE_ORDER(v)
996       && v->BitsPerPixel==24
997       && sizeof(GLuint)==4
998       && v->RedGamma==1.0 && v->GreenGamma==1.0 && v->BlueGamma==1.0) {
999      /* common packed 24 bpp config used on Linux */
1000      v->undithered_pf = v->dithered_pf = PF_8R8G8B24;
1001   }
1002   else if (GET_REDMASK(v)  ==0xf800
1003       &&   GET_GREENMASK(v)==0x07e0
1004       &&   GET_BLUEMASK(v) ==0x001f
1005       && CHECK_BYTE_ORDER(v)
1006       && v->BitsPerPixel==16
1007       && sizeof(GLushort)==2
1008       && v->RedGamma==1.0 && v->GreenGamma==1.0 && v->BlueGamma==1.0) {
1009      /* 5-6-5 color weight on common PC VGA boards */
1010      v->undithered_pf = PF_5R6G5B;
1011      v->dithered_pf = PF_Dither_5R6G5B;
1012   }
1013   else if (GET_REDMASK(v)  ==0xe0
1014       &&   GET_GREENMASK(v)==0x1c
1015       &&   GET_BLUEMASK(v) ==0x03
1016       && CHECK_FOR_HPCR(v)) {
1017      setup_8bit_hpcr( v );
1018   }
1019}
1020
1021
1022
1023/**
1024 * Setup RGB rendering for a window with a monochrome visual.
1025 */
1026static void
1027setup_monochrome( XMesaVisual v, XMesaBuffer b )
1028{
1029   (void) b;
1030   v->dithered_pf = v->undithered_pf = PF_1Bit;
1031   /* if black=1 then we must flip pixel values */
1032   v->bitFlip = (GET_BLACK_PIXEL(v) != 0);
1033}
1034
1035
1036
1037/**
1038 * When a context is bound for the first time, we can finally finish
1039 * initializing the context's visual and buffer information.
1040 * \param v  the XMesaVisual to initialize
1041 * \param b  the XMesaBuffer to initialize (may be NULL)
1042 * \param rgb_flag  TRUE = RGBA mode, FALSE = color index mode
1043 * \param window  the window/pixmap we're rendering into
1044 * \param cmap  the colormap associated with the window/pixmap
1045 * \return GL_TRUE=success, GL_FALSE=failure
1046 */
1047static GLboolean
1048initialize_visual_and_buffer(int client, XMesaVisual v, XMesaBuffer b,
1049                             GLboolean rgb_flag, XMesaDrawable window,
1050                             XMesaColormap cmap)
1051{
1052   ASSERT(!b || b->xm_visual == v);
1053
1054   /* Save true bits/pixel */
1055   v->BitsPerPixel = bits_per_pixel(v);
1056   assert(v->BitsPerPixel > 0);
1057
1058   if (rgb_flag == GL_FALSE) {
1059      /* COLOR-INDEXED WINDOW:
1060       * Even if the visual is TrueColor or DirectColor we treat it as
1061       * being color indexed.  This is weird but might be useful to someone.
1062       */
1063      v->dithered_pf = v->undithered_pf = PF_Index;
1064      v->mesa_visual.indexBits = GET_VISUAL_DEPTH(v);
1065   }
1066   else {
1067      /* RGB WINDOW:
1068       * We support RGB rendering into almost any kind of visual.
1069       */
1070      const int xclass = v->mesa_visual.visualType;
1071      if (xclass == GLX_TRUE_COLOR || xclass == GLX_DIRECT_COLOR) {
1072	 setup_truecolor( v, b, cmap );
1073      }
1074      else if (xclass == GLX_STATIC_GRAY && GET_VISUAL_DEPTH(v) == 1) {
1075	 setup_monochrome( v, b );
1076      }
1077      else if (xclass == GLX_GRAY_SCALE || xclass == GLX_STATIC_GRAY) {
1078         if (!setup_grayscale( client, v, b, cmap )) {
1079            return GL_FALSE;
1080         }
1081      }
1082      else if ((xclass == GLX_PSEUDO_COLOR || xclass == GLX_STATIC_COLOR)
1083               && GET_VISUAL_DEPTH(v)>=4 && GET_VISUAL_DEPTH(v)<=16) {
1084	 if (!setup_dithered_color( client, v, b, cmap )) {
1085            return GL_FALSE;
1086         }
1087      }
1088      else {
1089	 _mesa_warning(NULL, "XMesa: RGB mode rendering not supported in given visual.\n");
1090	 return GL_FALSE;
1091      }
1092      v->mesa_visual.indexBits = 0;
1093
1094      if (_mesa_getenv("MESA_NO_DITHER")) {
1095	 v->dithered_pf = v->undithered_pf;
1096      }
1097   }
1098
1099
1100   /*
1101    * If MESA_INFO env var is set print out some debugging info
1102    * which can help Brian figure out what's going on when a user
1103    * reports bugs.
1104    */
1105   if (_mesa_getenv("MESA_INFO")) {
1106      _mesa_printf("X/Mesa visual = %p\n", (void *) v);
1107      _mesa_printf("X/Mesa dithered pf = %u\n", v->dithered_pf);
1108      _mesa_printf("X/Mesa undithered pf = %u\n", v->undithered_pf);
1109      _mesa_printf("X/Mesa level = %d\n", v->mesa_visual.level);
1110      _mesa_printf("X/Mesa depth = %d\n", GET_VISUAL_DEPTH(v));
1111      _mesa_printf("X/Mesa bits per pixel = %d\n", v->BitsPerPixel);
1112   }
1113
1114   if (b && window) {
1115      /* Do window-specific initializations */
1116
1117      /* these should have been set in create_xmesa_buffer */
1118      ASSERT(b->frontxrb->drawable == window);
1119      ASSERT(b->frontxrb->pixmap == (XMesaPixmap) window);
1120
1121      /* Setup for single/double buffering */
1122      if (v->mesa_visual.doubleBufferMode) {
1123         /* Double buffered */
1124         b->shm = check_for_xshm( v->display );
1125      }
1126
1127      /* X11 graphics contexts */
1128#ifdef XFree86Server
1129      b->gc = CreateScratchGC(v->display, window->depth);
1130#else
1131      b->gc = XCreateGC( v->display, window, 0, NULL );
1132#endif
1133      XMesaSetFunction( v->display, b->gc, GXcopy );
1134
1135      /* cleargc - for glClear() */
1136#ifdef XFree86Server
1137      b->cleargc = CreateScratchGC(v->display, window->depth);
1138#else
1139      b->cleargc = XCreateGC( v->display, window, 0, NULL );
1140#endif
1141      XMesaSetFunction( v->display, b->cleargc, GXcopy );
1142
1143      /*
1144       * Don't generate Graphics Expose/NoExpose events in swapbuffers().
1145       * Patch contributed by Michael Pichler May 15, 1995.
1146       */
1147#ifdef XFree86Server
1148      b->swapgc = CreateScratchGC(v->display, window->depth);
1149      {
1150         CARD32 v[1];
1151         v[0] = FALSE;
1152         dixChangeGC(NullClient, b->swapgc, GCGraphicsExposures, v, NULL);
1153      }
1154#else
1155      {
1156         XGCValues gcvalues;
1157         gcvalues.graphics_exposures = False;
1158         b->swapgc = XCreateGC(v->display, window,
1159                               GCGraphicsExposures, &gcvalues);
1160      }
1161#endif
1162      XMesaSetFunction( v->display, b->swapgc, GXcopy );
1163      /*
1164       * Set fill style and tile pixmap once for all for HPCR stuff
1165       * (instead of doing it each time in clear_color_HPCR_pixmap())
1166       * Initialize whole stuff
1167       * Patch contributed by Jacques Leroy March 8, 1998.
1168       */
1169      if (v->hpcr_clear_flag && b->backxrb && b->backxrb->pixmap) {
1170         int i;
1171         for (i = 0; i < 16; i++) {
1172            XMesaPutPixel(v->hpcr_clear_ximage, i, 0, 0);
1173            XMesaPutPixel(v->hpcr_clear_ximage, i, 1, 0);
1174         }
1175         XMesaPutImage(b->display, (XMesaDrawable) v->hpcr_clear_pixmap,
1176                       b->cleargc, v->hpcr_clear_ximage, 0, 0, 0, 0, 16, 2);
1177         XMesaSetFillStyle( v->display, b->cleargc, FillTiled);
1178         XMesaSetTile( v->display, b->cleargc, v->hpcr_clear_pixmap );
1179      }
1180
1181      /* Initialize the row buffer XImage for use in write_color_span() */
1182#ifdef XFree86Server
1183      b->rowimage = XMesaCreateImage(GET_VISUAL_DEPTH(v), MAX_WIDTH, 1,
1184				     (char *)MALLOC(MAX_WIDTH*4));
1185#else
1186      b->rowimage = XCreateImage( v->display,
1187                                  v->visinfo->visual,
1188                                  v->visinfo->depth,
1189                                  ZPixmap, 0,           /*format, offset*/
1190                                  (char*) MALLOC(MAX_WIDTH*4),  /*data*/
1191                                  MAX_WIDTH, 1,         /*width, height*/
1192                                  32,                   /*bitmap_pad*/
1193                                  0                     /*bytes_per_line*/ );
1194#endif
1195      if (!b->rowimage)
1196         return GL_FALSE;
1197   }
1198
1199   return GL_TRUE;
1200}
1201
1202
1203
1204/*
1205 * Convert an RGBA color to a pixel value.
1206 */
1207unsigned long
1208xmesa_color_to_pixel(GLcontext *ctx,
1209                     GLubyte r, GLubyte g, GLubyte b, GLubyte a,
1210                     GLuint pixelFormat)
1211{
1212   XMesaContext xmesa = XMESA_CONTEXT(ctx);
1213   switch (pixelFormat) {
1214      case PF_Index:
1215         return 0;
1216      case PF_Truecolor:
1217         {
1218            unsigned long p;
1219            PACK_TRUECOLOR( p, r, g, b );
1220            return p;
1221         }
1222      case PF_8A8B8G8R:
1223         return PACK_8A8B8G8R( r, g, b, a );
1224      case PF_8A8R8G8B:
1225         return PACK_8A8R8G8B( r, g, b, a );
1226      case PF_8R8G8B:
1227         /* fall through */
1228      case PF_8R8G8B24:
1229         return PACK_8R8G8B( r, g, b );
1230      case PF_5R6G5B:
1231         return PACK_5R6G5B( r, g, b );
1232      case PF_Dither:
1233         {
1234            DITHER_SETUP;
1235            return DITHER( 1, 0, r, g, b );
1236         }
1237      case PF_1Bit:
1238         /* 382 = (3*255)/2 */
1239         return ((r+g+b) > 382) ^ xmesa->xm_visual->bitFlip;
1240      case PF_HPCR:
1241         return DITHER_HPCR(1, 1, r, g, b);
1242      case PF_Lookup:
1243         {
1244            LOOKUP_SETUP;
1245            return LOOKUP( r, g, b );
1246         }
1247      case PF_Grayscale:
1248         return GRAY_RGB( r, g, b );
1249      case PF_Dither_True:
1250         /* fall through */
1251      case PF_Dither_5R6G5B:
1252         {
1253            unsigned long p;
1254            PACK_TRUEDITHER(p, 1, 0, r, g, b);
1255            return p;
1256         }
1257      default:
1258         _mesa_problem(ctx, "Bad pixel format in xmesa_color_to_pixel");
1259   }
1260   return 0;
1261}
1262
1263
1264#define NUM_VISUAL_TYPES   6
1265
1266/**
1267 * Convert an X visual type to a GLX visual type.
1268 *
1269 * \param visualType X visual type (i.e., \c TrueColor, \c StaticGray, etc.)
1270 *        to be converted.
1271 * \return If \c visualType is a valid X visual type, a GLX visual type will
1272 *         be returned.  Otherwise \c GLX_NONE will be returned.
1273 *
1274 * \note
1275 * This code was lifted directly from lib/GL/glx/glcontextmodes.c in the
1276 * DRI CVS tree.
1277 */
1278static GLint
1279xmesa_convert_from_x_visual_type( int visualType )
1280{
1281    static const int glx_visual_types[ NUM_VISUAL_TYPES ] = {
1282	GLX_STATIC_GRAY,  GLX_GRAY_SCALE,
1283	GLX_STATIC_COLOR, GLX_PSEUDO_COLOR,
1284	GLX_TRUE_COLOR,   GLX_DIRECT_COLOR
1285    };
1286
1287    return ( (unsigned) visualType < NUM_VISUAL_TYPES )
1288	? glx_visual_types[ visualType ] : GLX_NONE;
1289}
1290
1291
1292/**********************************************************************/
1293/*****                       Public Functions                     *****/
1294/**********************************************************************/
1295
1296
1297/*
1298 * Create a new X/Mesa visual.
1299 * Input:  display - X11 display
1300 *         visinfo - an XVisualInfo pointer
1301 *         rgb_flag - GL_TRUE = RGB mode,
1302 *                    GL_FALSE = color index mode
1303 *         alpha_flag - alpha buffer requested?
1304 *         db_flag - GL_TRUE = double-buffered,
1305 *                   GL_FALSE = single buffered
1306 *         stereo_flag - stereo visual?
1307 *         ximage_flag - GL_TRUE = use an XImage for back buffer,
1308 *                       GL_FALSE = use an off-screen pixmap for back buffer
1309 *         depth_size - requested bits/depth values, or zero
1310 *         stencil_size - requested bits/stencil values, or zero
1311 *         accum_red_size - requested bits/red accum values, or zero
1312 *         accum_green_size - requested bits/green accum values, or zero
1313 *         accum_blue_size - requested bits/blue accum values, or zero
1314 *         accum_alpha_size - requested bits/alpha accum values, or zero
1315 *         num_samples - number of samples/pixel if multisampling, or zero
1316 *         level - visual level, usually 0
1317 *         visualCaveat - ala the GLX extension, usually GLX_NONE
1318 * Return;  a new XMesaVisual or 0 if error.
1319 */
1320XMesaVisual XMesaCreateVisual( XMesaDisplay *display,
1321                               XMesaVisualInfo visinfo,
1322                               GLboolean rgb_flag,
1323                               GLboolean alpha_flag,
1324                               GLboolean db_flag,
1325                               GLboolean stereo_flag,
1326                               GLboolean ximage_flag,
1327                               GLint depth_size,
1328                               GLint stencil_size,
1329                               GLint accum_red_size,
1330                               GLint accum_green_size,
1331                               GLint accum_blue_size,
1332                               GLint accum_alpha_size,
1333                               GLint num_samples,
1334                               GLint level,
1335                               GLint visualCaveat )
1336{
1337   char *gamma;
1338   XMesaVisual v;
1339   GLint red_bits, green_bits, blue_bits, alpha_bits;
1340
1341#ifndef XFree86Server
1342   /* For debugging only */
1343   if (_mesa_getenv("MESA_XSYNC")) {
1344      /* This makes debugging X easier.
1345       * In your debugger, set a breakpoint on _XError to stop when an
1346       * X protocol error is generated.
1347       */
1348      XSynchronize( display, 1 );
1349   }
1350#endif
1351
1352   v = (XMesaVisual) CALLOC_STRUCT(xmesa_visual);
1353   if (!v) {
1354      return NULL;
1355   }
1356
1357   /*
1358    * In the X server, NULL is passed in for the display.  It will have
1359    * to be set before using this visual.  See XMesaSetVisualDisplay()
1360    * below.
1361    */
1362   v->display = display;
1363
1364   /* Save a copy of the XVisualInfo struct because the user may X_mesa_free()
1365    * the struct but we may need some of the information contained in it
1366    * at a later time.
1367    */
1368#ifndef XFree86Server
1369   v->visinfo = (XVisualInfo *) MALLOC(sizeof(*visinfo));
1370   if(!v->visinfo) {
1371      _mesa_free(v);
1372      return NULL;
1373   }
1374   MEMCPY(v->visinfo, visinfo, sizeof(*visinfo));
1375#endif
1376
1377   /* check for MESA_GAMMA environment variable */
1378   gamma = _mesa_getenv("MESA_GAMMA");
1379   if (gamma) {
1380      v->RedGamma = v->GreenGamma = v->BlueGamma = 0.0;
1381      sscanf( gamma, "%f %f %f", &v->RedGamma, &v->GreenGamma, &v->BlueGamma );
1382      if (v->RedGamma<=0.0)    v->RedGamma = 1.0;
1383      if (v->GreenGamma<=0.0)  v->GreenGamma = v->RedGamma;
1384      if (v->BlueGamma<=0.0)   v->BlueGamma = v->RedGamma;
1385   }
1386   else {
1387      v->RedGamma = v->GreenGamma = v->BlueGamma = 1.0;
1388   }
1389
1390   v->ximage_flag = ximage_flag;
1391
1392#ifdef XFree86Server
1393   /* We could calculate these values by ourselves.  nplanes is either the sum
1394    * of the red, green, and blue bits or the number index bits.
1395    * ColormapEntries is either (1U << index_bits) or
1396    * (1U << max(redBits, greenBits, blueBits)).
1397    */
1398   assert(visinfo->nplanes > 0);
1399   v->nplanes = visinfo->nplanes;
1400   v->ColormapEntries = visinfo->ColormapEntries;
1401
1402   v->mesa_visual.redMask = visinfo->redMask;
1403   v->mesa_visual.greenMask = visinfo->greenMask;
1404   v->mesa_visual.blueMask = visinfo->blueMask;
1405   v->mesa_visual.visualID = visinfo->vid;
1406   v->mesa_visual.screen = 0; /* FIXME: What should be done here? */
1407#else
1408   v->mesa_visual.redMask = visinfo->red_mask;
1409   v->mesa_visual.greenMask = visinfo->green_mask;
1410   v->mesa_visual.blueMask = visinfo->blue_mask;
1411   v->mesa_visual.visualID = visinfo->visualid;
1412   v->mesa_visual.screen = visinfo->screen;
1413#endif
1414
1415#if defined(XFree86Server) || !(defined(__cplusplus) || defined(c_plusplus))
1416   v->mesa_visual.visualType = xmesa_convert_from_x_visual_type(visinfo->class);
1417#else
1418   v->mesa_visual.visualType = xmesa_convert_from_x_visual_type(visinfo->c_class);
1419#endif
1420
1421   v->mesa_visual.visualRating = visualCaveat;
1422
1423   (void) initialize_visual_and_buffer( 0, v, NULL, rgb_flag, 0, 0 );
1424
1425   {
1426      const int xclass = v->mesa_visual.visualType;
1427      if (xclass == GLX_TRUE_COLOR || xclass == GLX_DIRECT_COLOR) {
1428         red_bits   = _mesa_bitcount(GET_REDMASK(v));
1429         green_bits = _mesa_bitcount(GET_GREENMASK(v));
1430         blue_bits  = _mesa_bitcount(GET_BLUEMASK(v));
1431         alpha_bits = 0;
1432      }
1433      else {
1434         /* this is an approximation */
1435         int depth;
1436         depth = GET_VISUAL_DEPTH(v);
1437         red_bits = depth / 3;
1438         depth -= red_bits;
1439         green_bits = depth / 2;
1440         depth -= green_bits;
1441         blue_bits = depth;
1442         alpha_bits = 0;
1443         assert( red_bits + green_bits + blue_bits == GET_VISUAL_DEPTH(v) );
1444      }
1445   }
1446
1447   if (alpha_flag && alpha_bits == 0)
1448      alpha_bits = 8;
1449
1450   _mesa_initialize_visual( &v->mesa_visual,
1451                            rgb_flag, db_flag, stereo_flag,
1452                            red_bits, green_bits,
1453                            blue_bits, alpha_bits,
1454                            v->mesa_visual.indexBits,
1455                            depth_size,
1456                            stencil_size,
1457                            accum_red_size, accum_green_size,
1458                            accum_blue_size, accum_alpha_size,
1459                            0 );
1460
1461   /* XXX minor hack */
1462   v->mesa_visual.level = level;
1463   return v;
1464}
1465
1466
1467void XMesaSetVisualDisplay( XMesaDisplay *dpy, XMesaVisual v )
1468{
1469    v->display = dpy;
1470}
1471
1472
1473void XMesaDestroyVisual( XMesaVisual v )
1474{
1475#ifndef XFree86Server
1476   _mesa_free(v->visinfo);
1477#endif
1478   _mesa_free(v);
1479}
1480
1481
1482
1483/**
1484 * Create a new XMesaContext.
1485 * \param v  the XMesaVisual
1486 * \param share_list  another XMesaContext with which to share display
1487 *                    lists or NULL if no sharing is wanted.
1488 * \return an XMesaContext or NULL if error.
1489 */
1490XMesaContext XMesaCreateContext( XMesaVisual v, XMesaContext share_list )
1491{
1492   static GLboolean firstTime = GL_TRUE;
1493   XMesaContext c;
1494   GLcontext *mesaCtx;
1495   struct dd_function_table functions;
1496   TNLcontext *tnl;
1497
1498   if (firstTime) {
1499      _glthread_INIT_MUTEX(_xmesa_lock);
1500      firstTime = GL_FALSE;
1501   }
1502
1503   /* Note: the XMesaContext contains a Mesa GLcontext struct (inheritance) */
1504   c = (XMesaContext) CALLOC_STRUCT(xmesa_context);
1505   if (!c)
1506      return NULL;
1507
1508   mesaCtx = &(c->mesa);
1509
1510   /* initialize with default driver functions, then plug in XMesa funcs */
1511   _mesa_init_driver_functions(&functions);
1512   xmesa_init_driver_functions(v, &functions);
1513   if (!_mesa_initialize_context(mesaCtx, &v->mesa_visual,
1514                      share_list ? &(share_list->mesa) : (GLcontext *) NULL,
1515                      &functions, (void *) c)) {
1516      _mesa_free(c);
1517      return NULL;
1518   }
1519
1520   _mesa_enable_sw_extensions(mesaCtx);
1521   _mesa_enable_1_3_extensions(mesaCtx);
1522   _mesa_enable_1_4_extensions(mesaCtx);
1523   _mesa_enable_1_5_extensions(mesaCtx);
1524   _mesa_enable_2_0_extensions(mesaCtx);
1525#if ENABLE_EXT_texure_compression_s3tc
1526    if (c->Mesa_DXTn) {
1527       _mesa_enable_extension(mesaCtx, "GL_EXT_texture_compression_s3tc");
1528       _mesa_enable_extension(mesaCtx, "GL_S3_s3tc");
1529    }
1530    _mesa_enable_extension(mesaCtx, "GL_3DFX_texture_compression_FXT1");
1531#endif
1532#if ENABLE_EXT_timer_query
1533    _mesa_enable_extension(mesaCtx, "GL_EXT_timer_query");
1534#endif
1535
1536#ifdef XFree86Server
1537   /* If we're running in the X server, do bounds checking to prevent
1538    * segfaults and server crashes!
1539    */
1540   mesaCtx->Const.CheckArrayBounds = GL_TRUE;
1541#endif
1542
1543   /* finish up xmesa context initializations */
1544   c->swapbytes = CHECK_BYTE_ORDER(v) ? GL_FALSE : GL_TRUE;
1545   c->xm_visual = v;
1546   c->xm_buffer = NULL;   /* set later by XMesaMakeCurrent */
1547   c->display = v->display;
1548   c->pixelformat = v->dithered_pf;      /* Dithering is enabled by default */
1549
1550   /* Initialize the software rasterizer and helper modules.
1551    */
1552   if (!_swrast_CreateContext( mesaCtx ) ||
1553       !_vbo_CreateContext( mesaCtx ) ||
1554       !_tnl_CreateContext( mesaCtx ) ||
1555       !_swsetup_CreateContext( mesaCtx )) {
1556      _mesa_free_context_data(&c->mesa);
1557      _mesa_free(c);
1558      return NULL;
1559   }
1560
1561   /* tnl setup */
1562   tnl = TNL_CONTEXT(mesaCtx);
1563   tnl->Driver.RunPipeline = _tnl_run_pipeline;
1564   /* swrast setup */
1565   xmesa_register_swrast_functions( mesaCtx );
1566   _swsetup_Wakeup(mesaCtx);
1567
1568   return c;
1569}
1570
1571
1572
1573void XMesaDestroyContext( XMesaContext c )
1574{
1575   GLcontext *mesaCtx = &c->mesa;
1576#ifdef FX
1577   XMesaBuffer xmbuf = XMESA_BUFFER(mesaCtx->DrawBuffer);
1578
1579   if (xmbuf && xmbuf->FXctx)
1580      fxMesaDestroyContext(xmbuf->FXctx);
1581#endif
1582   _swsetup_DestroyContext( mesaCtx );
1583   _swrast_DestroyContext( mesaCtx );
1584   _tnl_DestroyContext( mesaCtx );
1585   _vbo_DestroyContext( mesaCtx );
1586   _mesa_free_context_data( mesaCtx );
1587   _mesa_free( c );
1588}
1589
1590
1591
1592/**
1593 * Private function for creating an XMesaBuffer which corresponds to an
1594 * X window or pixmap.
1595 * \param v  the window's XMesaVisual
1596 * \param w  the window we're wrapping
1597 * \param c  context used to initialize the buffer if 3Dfx mode in use.
1598 * \return  new XMesaBuffer or NULL if error
1599 */
1600XMesaBuffer
1601XMesaCreateWindowBuffer2(XMesaVisual v, XMesaWindow w, XMesaContext c)
1602{
1603#ifndef XFree86Server
1604   XWindowAttributes attr;
1605#endif
1606#ifdef FX
1607   char *fxEnvVar;
1608#endif
1609   int client = 0;
1610   XMesaBuffer b;
1611   XMesaColormap cmap;
1612
1613   assert(v);
1614   assert(w);
1615   (void) c;
1616
1617   /* Check that window depth matches visual depth */
1618#ifdef XFree86Server
1619   client = CLIENT_ID(((XMesaDrawable)w)->id);
1620
1621   if (GET_VISUAL_DEPTH(v) != ((XMesaDrawable)w)->depth) {
1622      _mesa_warning(NULL, "XMesaCreateWindowBuffer: depth mismatch between visual (%d) and window (%d)!\n",
1623                    GET_VISUAL_DEPTH(v), ((XMesaDrawable) w)->depth);
1624      return NULL;
1625   }
1626#else
1627   XGetWindowAttributes( v->display, w, &attr );
1628
1629   if (GET_VISUAL_DEPTH(v) != attr.depth) {
1630      _mesa_warning(NULL, "XMesaCreateWindowBuffer: depth mismatch between visual (%d) and window (%d)!\n",
1631                    GET_VISUAL_DEPTH(v), attr.depth);
1632      return NULL;
1633   }
1634#endif
1635
1636   /* Find colormap */
1637#ifdef XFree86Server
1638   cmap = (ColormapPtr)LookupIDByType(wColormap(w), RT_COLORMAP);
1639#else
1640   if (attr.colormap) {
1641      cmap = attr.colormap;
1642   }
1643   else {
1644      _mesa_warning(NULL, "Window %u has no colormap!\n", (unsigned int) w);
1645      /* this is weird, a window w/out a colormap!? */
1646      /* OK, let's just allocate a new one and hope for the best */
1647      cmap = XCreateColormap(v->display, w, attr.visual, AllocNone);
1648   }
1649#endif
1650
1651   b = create_xmesa_buffer((XMesaDrawable) w, WINDOW, v, cmap);
1652   if (!b)
1653      return NULL;
1654
1655   if (!initialize_visual_and_buffer( client, v, b, v->mesa_visual.rgbMode,
1656                                      (XMesaDrawable) w, cmap )) {
1657      xmesa_free_buffer(b);
1658      return NULL;
1659   }
1660
1661#ifdef FX
1662   fxEnvVar = _mesa_getenv("MESA_GLX_FX");
1663   if (fxEnvVar) {
1664     if (fxEnvVar[0]!='d') {
1665       int attribs[100];
1666       int numAttribs = 0;
1667       int hw;
1668       if (v->mesa_visual.depthBits > 0) {
1669	 attribs[numAttribs++] = FXMESA_DEPTH_SIZE;
1670	 attribs[numAttribs++] = v->mesa_visual.depthBits;
1671       }
1672       if (v->mesa_visual.doubleBufferMode) {
1673	 attribs[numAttribs++] = FXMESA_DOUBLEBUFFER;
1674       }
1675       if (v->mesa_visual.accumRedBits > 0) {
1676	 attribs[numAttribs++] = FXMESA_ACCUM_SIZE;
1677	 attribs[numAttribs++] = v->mesa_visual.accumRedBits;
1678       }
1679       if (v->mesa_visual.stencilBits > 0) {
1680         attribs[numAttribs++] = FXMESA_STENCIL_SIZE;
1681         attribs[numAttribs++] = v->mesa_visual.stencilBits;
1682       }
1683       if (v->mesa_visual.alphaBits > 0) {
1684         attribs[numAttribs++] = FXMESA_ALPHA_SIZE;
1685         attribs[numAttribs++] = v->mesa_visual.alphaBits;
1686       }
1687       if (1) {
1688         attribs[numAttribs++] = FXMESA_SHARE_CONTEXT;
1689         attribs[numAttribs++] = (int) &(c->mesa);
1690       }
1691       attribs[numAttribs++] = FXMESA_NONE;
1692
1693       /* [dBorca] we should take an envvar for `fxMesaSelectCurrentBoard'!!! */
1694       hw = fxMesaSelectCurrentBoard(0);
1695
1696       /* if these fail, there's a new bug somewhere */
1697       ASSERT(b->mesa_buffer.Width > 0);
1698       ASSERT(b->mesa_buffer.Height > 0);
1699
1700       if ((hw == GR_SSTTYPE_VOODOO) || (hw == GR_SSTTYPE_Voodoo2)) {
1701         b->FXctx = fxMesaCreateBestContext(0, b->mesa_buffer.Width,
1702                                            b->mesa_buffer.Height, attribs);
1703         if ((v->undithered_pf!=PF_Index) && (b->backxrb->ximage)) {
1704	   b->FXisHackUsable = b->FXctx ? GL_TRUE : GL_FALSE;
1705	   if (b->FXctx && (fxEnvVar[0]=='w' || fxEnvVar[0]=='W')) {
1706	     b->FXwindowHack = GL_TRUE;
1707	     FX_grSstControl(GR_CONTROL_DEACTIVATE);
1708	   }
1709           else {
1710	     b->FXwindowHack = GL_FALSE;
1711	   }
1712         }
1713       }
1714       else {
1715         if (fxEnvVar[0]=='w' || fxEnvVar[0]=='W')
1716	   b->FXctx = fxMesaCreateContext(w, GR_RESOLUTION_NONE,
1717					  GR_REFRESH_75Hz, attribs);
1718         else
1719	   b->FXctx = fxMesaCreateBestContext(0, b->mesa_buffer.Width,
1720                                              b->mesa_buffer.Height, attribs);
1721         b->FXisHackUsable = GL_FALSE;
1722         b->FXwindowHack = GL_FALSE;
1723       }
1724       /*
1725       fprintf(stderr,
1726               "voodoo %d, wid %d height %d hack: usable %d active %d\n",
1727               hw, b->mesa_buffer.Width, b->mesa_buffer.Height,
1728	       b->FXisHackUsable, b->FXwindowHack);
1729       */
1730     }
1731   }
1732   else {
1733      _mesa_warning(NULL, "WARNING: This Mesa Library includes the Glide driver but\n");
1734      _mesa_warning(NULL, "         you have not defined the MESA_GLX_FX env. var.\n");
1735      _mesa_warning(NULL, "         (check the README.3DFX file for more information).\n\n");
1736      _mesa_warning(NULL, "         you can disable this message with a 'export MESA_GLX_FX=disable'.\n");
1737   }
1738#endif
1739
1740   return b;
1741}
1742
1743
1744XMesaBuffer
1745XMesaCreateWindowBuffer(XMesaVisual v, XMesaWindow w)
1746{
1747   return XMesaCreateWindowBuffer2( v, w, NULL );
1748}
1749
1750
1751/**
1752 * Create a new XMesaBuffer from an X pixmap.
1753 *
1754 * \param v    the XMesaVisual
1755 * \param p    the pixmap
1756 * \param cmap the colormap, may be 0 if using a \c GLX_TRUE_COLOR or
1757 *             \c GLX_DIRECT_COLOR visual for the pixmap
1758 * \returns new XMesaBuffer or NULL if error
1759 */
1760XMesaBuffer
1761XMesaCreatePixmapBuffer(XMesaVisual v, XMesaPixmap p, XMesaColormap cmap)
1762{
1763   int client = 0;
1764   XMesaBuffer b;
1765
1766   assert(v);
1767
1768   b = create_xmesa_buffer((XMesaDrawable) p, PIXMAP, v, cmap);
1769   if (!b)
1770      return NULL;
1771
1772#ifdef XFree86Server
1773   client = CLIENT_ID(((XMesaDrawable)p)->id);
1774#endif
1775
1776   if (!initialize_visual_and_buffer(client, v, b, v->mesa_visual.rgbMode,
1777				     (XMesaDrawable) p, cmap)) {
1778      xmesa_free_buffer(b);
1779      return NULL;
1780   }
1781
1782   return b;
1783}
1784
1785
1786
1787XMesaBuffer
1788XMesaCreatePBuffer(XMesaVisual v, XMesaColormap cmap,
1789                   unsigned int width, unsigned int height)
1790{
1791#ifdef XFree86Server
1792   return 0;
1793#else
1794   int client = 0;
1795   XMesaWindow root;
1796   XMesaDrawable drawable;  /* X Pixmap Drawable */
1797   XMesaBuffer b;
1798
1799   /* allocate pixmap for front buffer */
1800   root = RootWindow( v->display, v->visinfo->screen );
1801   drawable = XCreatePixmap(v->display, root, width, height,
1802                            v->visinfo->depth);
1803   if (!drawable)
1804      return NULL;
1805
1806   b = create_xmesa_buffer(drawable, PBUFFER, v, cmap);
1807   if (!b)
1808      return NULL;
1809
1810   if (!initialize_visual_and_buffer(client, v, b, v->mesa_visual.rgbMode,
1811				     drawable, cmap)) {
1812      xmesa_free_buffer(b);
1813      return NULL;
1814   }
1815
1816   return b;
1817#endif
1818}
1819
1820
1821
1822/*
1823 * Deallocate an XMesaBuffer structure and all related info.
1824 */
1825void
1826XMesaDestroyBuffer(XMesaBuffer b)
1827{
1828   xmesa_free_buffer(b);
1829}
1830
1831
1832/**
1833 * Query the current window size and update the corresponding GLframebuffer
1834 * and all attached renderbuffers.
1835 * Called when:
1836 *  1. the first time a buffer is bound to a context.
1837 *  2. from glViewport to poll for window size changes
1838 *  3. from the XMesaResizeBuffers() API function.
1839 */
1840void
1841xmesa_check_and_update_buffer_size(XMesaContext xmctx, XMesaBuffer drawBuffer)
1842{
1843   GLuint width, height;
1844   xmesa_get_window_size(xmctx->display, drawBuffer, &width, &height);
1845   if (drawBuffer->mesa_buffer.Width != width ||
1846       drawBuffer->mesa_buffer.Height != height) {
1847      _mesa_resize_framebuffer(&(xmctx->mesa),
1848                               &(drawBuffer->mesa_buffer), width, height);
1849   }
1850   drawBuffer->mesa_buffer.Initialized = GL_TRUE; /* XXX TEMPORARY? */
1851}
1852
1853
1854/*
1855 * Bind buffer b to context c and make c the current rendering context.
1856 */
1857GLboolean XMesaMakeCurrent( XMesaContext c, XMesaBuffer b )
1858{
1859   return XMesaMakeCurrent2( c, b, b );
1860}
1861
1862
1863/*
1864 * Bind buffer b to context c and make c the current rendering context.
1865 */
1866GLboolean XMesaMakeCurrent2( XMesaContext c, XMesaBuffer drawBuffer,
1867                             XMesaBuffer readBuffer )
1868{
1869   if (c) {
1870      if (!drawBuffer || !readBuffer)
1871         return GL_FALSE;  /* must specify buffers! */
1872
1873#ifdef FX
1874      if (drawBuffer->FXctx) {
1875         fxMesaMakeCurrent(drawBuffer->FXctx);
1876
1877         c->xm_buffer = drawBuffer;
1878
1879         return GL_TRUE;
1880      }
1881#endif
1882      if (&(c->mesa) == _mesa_get_current_context()
1883          && c->mesa.DrawBuffer == &drawBuffer->mesa_buffer
1884          && c->mesa.ReadBuffer == &readBuffer->mesa_buffer
1885          && XMESA_BUFFER(c->mesa.DrawBuffer)->wasCurrent) {
1886         /* same context and buffer, do nothing */
1887         return GL_TRUE;
1888      }
1889
1890      c->xm_buffer = drawBuffer;
1891
1892      /* Call this periodically to detect when the user has begun using
1893       * GL rendering from multiple threads.
1894       */
1895      _glapi_check_multithread();
1896
1897      xmesa_check_and_update_buffer_size(c, drawBuffer);
1898      if (readBuffer != drawBuffer)
1899         xmesa_check_and_update_buffer_size(c, readBuffer);
1900
1901      _mesa_make_current(&(c->mesa),
1902                         &drawBuffer->mesa_buffer,
1903                         &readBuffer->mesa_buffer);
1904
1905      if (c->xm_visual->mesa_visual.rgbMode) {
1906         /*
1907          * Must recompute and set these pixel values because colormap
1908          * can be different for different windows.
1909          */
1910         c->clearpixel = xmesa_color_to_pixel( &c->mesa,
1911                                               c->clearcolor[0],
1912                                               c->clearcolor[1],
1913                                               c->clearcolor[2],
1914                                               c->clearcolor[3],
1915                                               c->xm_visual->undithered_pf);
1916         XMesaSetForeground(c->display, drawBuffer->cleargc, c->clearpixel);
1917      }
1918
1919      /* Solution to Stephane Rehel's problem with glXReleaseBuffersMESA(): */
1920      drawBuffer->wasCurrent = GL_TRUE;
1921   }
1922   else {
1923      /* Detach */
1924      _mesa_make_current( NULL, NULL, NULL );
1925   }
1926   return GL_TRUE;
1927}
1928
1929
1930/*
1931 * Unbind the context c from its buffer.
1932 */
1933GLboolean XMesaUnbindContext( XMesaContext c )
1934{
1935   /* A no-op for XFree86 integration purposes */
1936   return GL_TRUE;
1937}
1938
1939
1940XMesaContext XMesaGetCurrentContext( void )
1941{
1942   GET_CURRENT_CONTEXT(ctx);
1943   if (ctx) {
1944      XMesaContext xmesa = XMESA_CONTEXT(ctx);
1945      return xmesa;
1946   }
1947   else {
1948      return 0;
1949   }
1950}
1951
1952
1953XMesaBuffer XMesaGetCurrentBuffer( void )
1954{
1955   GET_CURRENT_CONTEXT(ctx);
1956   if (ctx) {
1957      XMesaBuffer xmbuf = XMESA_BUFFER(ctx->DrawBuffer);
1958      return xmbuf;
1959   }
1960   else {
1961      return 0;
1962   }
1963}
1964
1965
1966/* New in Mesa 3.1 */
1967XMesaBuffer XMesaGetCurrentReadBuffer( void )
1968{
1969   GET_CURRENT_CONTEXT(ctx);
1970   if (ctx) {
1971      return XMESA_BUFFER(ctx->ReadBuffer);
1972   }
1973   else {
1974      return 0;
1975   }
1976}
1977
1978
1979GLboolean XMesaForceCurrent(XMesaContext c)
1980{
1981   if (c) {
1982      if (&(c->mesa) != _mesa_get_current_context()) {
1983	 _mesa_make_current(&c->mesa, c->mesa.DrawBuffer, c->mesa.ReadBuffer);
1984      }
1985   }
1986   else {
1987      _mesa_make_current(NULL, NULL, NULL);
1988   }
1989   return GL_TRUE;
1990}
1991
1992
1993GLboolean XMesaLoseCurrent(XMesaContext c)
1994{
1995   (void) c;
1996   _mesa_make_current(NULL, NULL, NULL);
1997   return GL_TRUE;
1998}
1999
2000
2001/*
2002 * Switch 3Dfx support hack between window and full-screen mode.
2003 */
2004GLboolean XMesaSetFXmode( GLint mode )
2005{
2006#ifdef FX
2007   const char *fx = _mesa_getenv("MESA_GLX_FX");
2008   if (fx && fx[0] != 'd') {
2009      GET_CURRENT_CONTEXT(ctx);
2010      GrHwConfiguration hw;
2011      if (!FX_grSstQueryHardware(&hw)) {
2012         /*fprintf(stderr, "!grSstQueryHardware\n");*/
2013         return GL_FALSE;
2014      }
2015      if (hw.num_sst < 1) {
2016         /*fprintf(stderr, "hw.num_sst < 1\n");*/
2017         return GL_FALSE;
2018      }
2019      if (ctx) {
2020         /* [dBorca] Hack alert:
2021	  * oh, this is sooo wrong: ctx above is
2022	  * really an fxMesaContext, not an XMesaContext
2023	  */
2024         XMesaBuffer xmbuf = XMESA_BUFFER(ctx->DrawBuffer);
2025         if (mode == XMESA_FX_WINDOW) {
2026	    if (xmbuf->FXisHackUsable) {
2027	       FX_grSstControl(GR_CONTROL_DEACTIVATE);
2028	       xmbuf->FXwindowHack = GL_TRUE;
2029	       return GL_TRUE;
2030	    }
2031	 }
2032	 else if (mode == XMESA_FX_FULLSCREEN) {
2033	    FX_grSstControl(GR_CONTROL_ACTIVATE);
2034	    xmbuf->FXwindowHack = GL_FALSE;
2035	    return GL_TRUE;
2036	 }
2037	 else {
2038	    /* Error: Bad mode value */
2039	 }
2040      }
2041   }
2042   /*fprintf(stderr, "fallthrough\n");*/
2043#else
2044   (void) mode;
2045#endif
2046   return GL_FALSE;
2047}
2048
2049
2050
2051#ifdef FX
2052/*
2053 * Read image from VooDoo frame buffer into X/Mesa's back XImage.
2054 */
2055static void FXgetImage( XMesaBuffer b )
2056{
2057   GET_CURRENT_CONTEXT(ctx);
2058   static unsigned short pixbuf[MAX_WIDTH];
2059   GLuint x, y;
2060   GLuint width, height;
2061   XMesaContext xmesa = XMESA_CONTEXT(ctx);
2062
2063#ifdef XFree86Server
2064   x = b->frontxrb->pixmap->x;
2065   y = b->frontxrb->pixmap->y;
2066   width = b->frontxrb->pixmap->width;
2067   height = b->frontxrb->pixmap->height;
2068   depth = b->frontxrb->pixmap->depth;
2069#else
2070   xmesa_get_window_size(b->display, b, &width, &height);
2071   x = y = 0;
2072#endif
2073   if (b->mesa_buffer.Width != width || b->mesa_buffer.Height != height) {
2074      b->mesa_buffer.Width = MIN2((int)width, b->FXctx->width);
2075      b->mesa_buffer.Height = MIN2((int)height, b->FXctx->height);
2076      if (b->mesa_buffer.Width & 1)
2077         b->mesa_buffer.Width--;  /* prevent odd width */
2078   }
2079
2080   /* [dBorca] we're always in the right GR_COLORFORMAT... aren't we? */
2081   /* grLfbWriteColorFormat(GR_COLORFORMAT_ARGB); */
2082   if (b->xm_visual->undithered_pf==PF_5R6G5B) {
2083      /* Special case: 16bpp RGB */
2084      grLfbReadRegion( GR_BUFFER_FRONTBUFFER,       /* src buffer */
2085                       0, b->FXctx->height - b->mesa_buffer.Height,  /*pos*/
2086                       b->mesa_buffer.Width, b->mesa_buffer.Height,  /* size */
2087                       b->mesa_buffer.Width * sizeof(GLushort), /* stride */
2088                       b->backxrb->ximage->data);         /* dest buffer */
2089   }
2090   else if (b->xm_visual->dithered_pf==PF_Dither
2091	    && GET_VISUAL_DEPTH(b->xm_visual)==8) {
2092      /* Special case: 8bpp RGB */
2093      for (y=0;y<b->mesa_buffer.Height;y++) {
2094         GLubyte *ptr = (GLubyte*) b->backxrb->ximage->data
2095                        + b->backxrb->ximage->bytes_per_line * y;
2096         XDITHER_SETUP(y);
2097
2098         /* read row from 3Dfx frame buffer */
2099         grLfbReadRegion( GR_BUFFER_FRONTBUFFER,
2100                          0, b->FXctx->height-(b->mesa_buffer.Height-y),
2101                          b->mesa_buffer.Width, 1,
2102                          0,
2103                          pixbuf );
2104
2105         /* write to XImage back buffer */
2106         for (x=0;x<b->mesa_buffer.Width;x++) {
2107            GLubyte r = (pixbuf[x] & 0xf800) >> 8;
2108            GLubyte g = (pixbuf[x] & 0x07e0) >> 3;
2109            GLubyte b = (pixbuf[x] & 0x001f) << 3;
2110            *ptr++ = XDITHER( x, r, g, b);
2111         }
2112      }
2113   }
2114   else {
2115      /* General case: slow! */
2116      for (y=0;y<b->mesa_buffer.Height;y++) {
2117         /* read row from 3Dfx frame buffer */
2118         grLfbReadRegion( GR_BUFFER_FRONTBUFFER,
2119                          0, b->FXctx->height-(b->mesa_buffer.Height-y),
2120                          b->mesa_buffer.Width, 1,
2121                          0,
2122                          pixbuf );
2123
2124         /* write to XImage back buffer */
2125         for (x=0;x<b->mesa_buffer.Width;x++) {
2126            XMesaPutPixel(b->backxrb->ximage,x,y,
2127			  xmesa_color_to_pixel(ctx,
2128					       (pixbuf[x] & 0xf800) >> 8,
2129					       (pixbuf[x] & 0x07e0) >> 3,
2130					       (pixbuf[x] & 0x001f) << 3,
2131					       0xff,
2132                                               b->xm_visual->undithered_pf));
2133         }
2134      }
2135   }
2136   /* grLfbWriteColorFormat(GR_COLORFORMAT_ABGR); */
2137}
2138#endif
2139
2140
2141/*
2142 * Copy the back buffer to the front buffer.  If there's no back buffer
2143 * this is a no-op.
2144 */
2145void XMesaSwapBuffers( XMesaBuffer b )
2146{
2147   GET_CURRENT_CONTEXT(ctx);
2148
2149   if (!b->backxrb) {
2150      /* single buffered */
2151      return;
2152   }
2153
2154   /* If we're swapping the buffer associated with the current context
2155    * we have to flush any pending rendering commands first.
2156    */
2157   if (ctx && ctx->DrawBuffer == &(b->mesa_buffer))
2158      _mesa_notifySwapBuffers(ctx);
2159
2160   if (b->db_mode) {
2161#ifdef FX
2162      if (b->FXctx) {
2163         fxMesaSwapBuffers();
2164
2165         if (b->FXwindowHack)
2166            FXgetImage(b);
2167         else
2168            return;
2169      }
2170#endif
2171     if (b->backxrb->ximage) {
2172	 /* Copy Ximage from host's memory to server's window */
2173#if defined(USE_XSHM) && !defined(XFree86Server)
2174	 if (b->shm) {
2175            /*_glthread_LOCK_MUTEX(_xmesa_lock);*/
2176	    XShmPutImage( b->xm_visual->display, b->frontxrb->drawable,
2177			  b->swapgc,
2178			  b->backxrb->ximage, 0, 0,
2179			  0, 0, b->mesa_buffer.Width, b->mesa_buffer.Height,
2180                          False );
2181            /*_glthread_UNLOCK_MUTEX(_xmesa_lock);*/
2182	 }
2183	 else
2184#endif
2185         {
2186            /*_glthread_LOCK_MUTEX(_xmesa_lock);*/
2187            XMesaPutImage( b->xm_visual->display, b->frontxrb->drawable,
2188			   b->swapgc,
2189			   b->backxrb->ximage, 0, 0,
2190			   0, 0, b->mesa_buffer.Width, b->mesa_buffer.Height );
2191            /*_glthread_UNLOCK_MUTEX(_xmesa_lock);*/
2192         }
2193      }
2194      else {
2195	 /* Copy pixmap to window on server */
2196         /*_glthread_LOCK_MUTEX(_xmesa_lock);*/
2197	 XMesaCopyArea( b->xm_visual->display,
2198			b->backxrb->pixmap,   /* source drawable */
2199			b->frontxrb->drawable,  /* dest. drawable */
2200			b->swapgc,
2201			0, 0, b->mesa_buffer.Width, b->mesa_buffer.Height,
2202			0, 0                 /* dest region */
2203		      );
2204         /*_glthread_UNLOCK_MUTEX(_xmesa_lock);*/
2205      }
2206   }
2207#if !defined(XFree86Server)
2208   XSync( b->xm_visual->display, False );
2209#endif
2210}
2211
2212
2213
2214/*
2215 * Copy sub-region of back buffer to front buffer
2216 */
2217void XMesaCopySubBuffer( XMesaBuffer b, int x, int y, int width, int height )
2218{
2219   GET_CURRENT_CONTEXT(ctx);
2220
2221   /* If we're swapping the buffer associated with the current context
2222    * we have to flush any pending rendering commands first.
2223    */
2224   if (ctx && ctx->DrawBuffer == &(b->mesa_buffer))
2225      _mesa_notifySwapBuffers(ctx);
2226
2227   if (!b->backxrb) {
2228      /* single buffered */
2229      return;
2230   }
2231
2232   if (b->db_mode) {
2233      int yTop = b->mesa_buffer.Height - y - height;
2234#ifdef FX
2235      if (b->FXctx) {
2236         fxMesaSwapBuffers();
2237         if (b->FXwindowHack)
2238            FXgetImage(b);
2239         else
2240            return;
2241      }
2242#endif
2243      if (b->backxrb->ximage) {
2244         /* Copy Ximage from host's memory to server's window */
2245#if defined(USE_XSHM) && !defined(XFree86Server)
2246         if (b->shm) {
2247            /* XXX assuming width and height aren't too large! */
2248            XShmPutImage( b->xm_visual->display, b->frontxrb->drawable,
2249                          b->swapgc,
2250                          b->backxrb->ximage, x, yTop,
2251                          x, yTop, width, height, False );
2252            /* wait for finished event??? */
2253         }
2254         else
2255#endif
2256         {
2257            /* XXX assuming width and height aren't too large! */
2258            XMesaPutImage( b->xm_visual->display, b->frontxrb->drawable,
2259			   b->swapgc,
2260			   b->backxrb->ximage, x, yTop,
2261			   x, yTop, width, height );
2262         }
2263      }
2264      else {
2265         /* Copy pixmap to window on server */
2266         XMesaCopyArea( b->xm_visual->display,
2267			b->backxrb->pixmap,           /* source drawable */
2268			b->frontxrb->drawable,        /* dest. drawable */
2269			b->swapgc,
2270			x, yTop, width, height,  /* source region */
2271			x, yTop                  /* dest region */
2272                      );
2273      }
2274   }
2275}
2276
2277
2278/*
2279 * Return a pointer to the XMesa backbuffer Pixmap or XImage.  This function
2280 * is a way to get "under the hood" of X/Mesa so one can manipulate the
2281 * back buffer directly.
2282 * Output:  pixmap - pointer to back buffer's Pixmap, or 0
2283 *          ximage - pointer to back buffer's XImage, or NULL
2284 * Return:  GL_TRUE = context is double buffered
2285 *          GL_FALSE = context is single buffered
2286 */
2287#ifndef XFree86Server
2288GLboolean XMesaGetBackBuffer( XMesaBuffer b,
2289                              XMesaPixmap *pixmap,
2290                              XMesaImage **ximage )
2291{
2292   if (b->db_mode) {
2293      if (pixmap)
2294         *pixmap = b->backxrb->pixmap;
2295      if (ximage)
2296         *ximage = b->backxrb->ximage;
2297      return GL_TRUE;
2298   }
2299   else {
2300      *pixmap = 0;
2301      *ximage = NULL;
2302      return GL_FALSE;
2303   }
2304}
2305#endif /* XFree86Server */
2306
2307
2308/*
2309 * Return the depth buffer associated with an XMesaBuffer.
2310 * Input:  b - the XMesa buffer handle
2311 * Output:  width, height - size of buffer in pixels
2312 *          bytesPerValue - bytes per depth value (2 or 4)
2313 *          buffer - pointer to depth buffer values
2314 * Return:  GL_TRUE or GL_FALSE to indicate success or failure.
2315 */
2316GLboolean XMesaGetDepthBuffer( XMesaBuffer b, GLint *width, GLint *height,
2317                               GLint *bytesPerValue, void **buffer )
2318{
2319   struct gl_renderbuffer *rb
2320      = b->mesa_buffer.Attachment[BUFFER_DEPTH].Renderbuffer;
2321   if (!rb || !rb->Data) {
2322      *width = 0;
2323      *height = 0;
2324      *bytesPerValue = 0;
2325      *buffer = 0;
2326      return GL_FALSE;
2327   }
2328   else {
2329      *width = b->mesa_buffer.Width;
2330      *height = b->mesa_buffer.Height;
2331      *bytesPerValue = b->mesa_buffer.Visual.depthBits <= 16
2332         ? sizeof(GLushort) : sizeof(GLuint);
2333      *buffer = rb->Data;
2334      return GL_TRUE;
2335   }
2336}
2337
2338
2339void XMesaFlush( XMesaContext c )
2340{
2341   if (c && c->xm_visual) {
2342#ifdef XFree86Server
2343      /* NOT_NEEDED */
2344#else
2345      XSync( c->xm_visual->display, False );
2346#endif
2347   }
2348}
2349
2350
2351
2352const char *XMesaGetString( XMesaContext c, int name )
2353{
2354   (void) c;
2355   if (name==XMESA_VERSION) {
2356      return "5.0";
2357   }
2358   else if (name==XMESA_EXTENSIONS) {
2359      return "";
2360   }
2361   else {
2362      return NULL;
2363   }
2364}
2365
2366
2367
2368XMesaBuffer XMesaFindBuffer( XMesaDisplay *dpy, XMesaDrawable d )
2369{
2370   XMesaBuffer b;
2371   for (b=XMesaBufferList; b; b=b->Next) {
2372      if (b->frontxrb->drawable == d && b->display == dpy) {
2373         return b;
2374      }
2375   }
2376   return NULL;
2377}
2378
2379
2380/**
2381 * Free/destroy all XMesaBuffers associated with given display.
2382 */
2383void xmesa_destroy_buffers_on_display(XMesaDisplay *dpy)
2384{
2385   XMesaBuffer b, next;
2386   for (b = XMesaBufferList; b; b = next) {
2387      next = b->Next;
2388      if (b->display == dpy) {
2389         xmesa_free_buffer(b);
2390      }
2391   }
2392}
2393
2394
2395/*
2396 * Look for XMesaBuffers whose X window has been destroyed.
2397 * Deallocate any such XMesaBuffers.
2398 */
2399void XMesaGarbageCollect( void )
2400{
2401   XMesaBuffer b, next;
2402   for (b=XMesaBufferList; b; b=next) {
2403      next = b->Next;
2404      if (b->display && b->frontxrb->drawable && b->type == WINDOW) {
2405#ifdef XFree86Server
2406	 /* NOT_NEEDED */
2407#else
2408         XSync(b->display, False);
2409         if (!window_exists( b->display, b->frontxrb->drawable )) {
2410            /* found a dead window, free the ancillary info */
2411            XMesaDestroyBuffer( b );
2412         }
2413#endif
2414      }
2415   }
2416}
2417
2418
2419void XMesaReset( void )
2420{
2421    while (XMesaBufferList)
2422	XMesaDestroyBuffer(XMesaBufferList);
2423
2424    XMesaBufferList = NULL;
2425}
2426
2427
2428unsigned long XMesaDitherColor( XMesaContext xmesa, GLint x, GLint y,
2429                                GLfloat red, GLfloat green,
2430                                GLfloat blue, GLfloat alpha )
2431{
2432   GLcontext *ctx = &xmesa->mesa;
2433   GLint r = (GLint) (red   * 255.0F);
2434   GLint g = (GLint) (green * 255.0F);
2435   GLint b = (GLint) (blue  * 255.0F);
2436   GLint a = (GLint) (alpha * 255.0F);
2437
2438   switch (xmesa->pixelformat) {
2439      case PF_Index:
2440         return 0;
2441      case PF_Truecolor:
2442         {
2443            unsigned long p;
2444            PACK_TRUECOLOR( p, r, g, b );
2445            return p;
2446         }
2447      case PF_8A8B8G8R:
2448         return PACK_8A8B8G8R( r, g, b, a );
2449      case PF_8A8R8G8B:
2450         return PACK_8A8R8G8B( r, g, b, a );
2451      case PF_8R8G8B:
2452         return PACK_8R8G8B( r, g, b );
2453      case PF_5R6G5B:
2454         return PACK_5R6G5B( r, g, b );
2455      case PF_Dither:
2456         {
2457            DITHER_SETUP;
2458            return DITHER( x, y, r, g, b );
2459         }
2460      case PF_1Bit:
2461         /* 382 = (3*255)/2 */
2462         return ((r+g+b) > 382) ^ xmesa->xm_visual->bitFlip;
2463      case PF_HPCR:
2464         return DITHER_HPCR(x, y, r, g, b);
2465      case PF_Lookup:
2466         {
2467            LOOKUP_SETUP;
2468            return LOOKUP( r, g, b );
2469         }
2470      case PF_Grayscale:
2471         return GRAY_RGB( r, g, b );
2472      case PF_Dither_5R6G5B:
2473         /* fall through */
2474      case PF_Dither_True:
2475         {
2476            unsigned long p;
2477            PACK_TRUEDITHER(p, x, y, r, g, b);
2478            return p;
2479         }
2480      default:
2481         _mesa_problem(NULL, "Bad pixel format in XMesaDitherColor");
2482   }
2483   return 0;
2484}
2485
2486
2487/*
2488 * This is typically called when the window size changes and we need
2489 * to reallocate the buffer's back/depth/stencil/accum buffers.
2490 */
2491void
2492XMesaResizeBuffers( XMesaBuffer b )
2493{
2494   GET_CURRENT_CONTEXT(ctx);
2495   XMesaContext xmctx = XMESA_CONTEXT(ctx);
2496   xmesa_check_and_update_buffer_size(xmctx, b);
2497}
2498
2499