xm_api.c revision 18514500c47ce8f30bb9cc93ab48bf55ccdb9873 
1/*
2 * Mesa 3-D graphics library
3 * Version:  6.1
4 *
5 * Copyright (C) 1999-2004  Brian Paul   All Rights Reserved.
6 *
7 * Permission is hereby granted, free of charge, to any person obtaining a
8 * copy of this software and associated documentation files (the "Software"),
9 * to deal in the Software without restriction, including without limitation
10 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
11 * and/or sell copies of the Software, and to permit persons to whom the
12 * Software is furnished to do so, subject to the following conditions:
13 *
14 * The above copyright notice and this permission notice shall be included
15 * in all copies or substantial portions of the Software.
16 *
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
18 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
20 * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
21 * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
22 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
23 */
24
25/*
26 * This file contains the implementations of all the XMesa* functions.
27 *
28 *
29 * NOTES:
30 *
31 * The window coordinate system origin (0,0) is in the lower-left corner
32 * of the window.  X11's window coordinate origin is in the upper-left
33 * corner of the window.  Therefore, most drawing functions in this
34 * file have to flip Y coordinates.
35 *
36 * Define USE_XSHM in the Makefile with -DUSE_XSHM if you want to compile
37 * in support for the MIT Shared Memory extension.  If enabled, when you
38 * use an Ximage for the back buffer in double buffered mode, the "swap"
39 * operation will be faster.  You must also link with -lXext.
40 *
41 * Byte swapping:  If the Mesa host and the X display use a different
42 * byte order then there's some trickiness to be aware of when using
43 * XImages.  The byte ordering used for the XImage is that of the X
44 * display, not the Mesa host.
45 * The color-to-pixel encoding for True/DirectColor must be done
46 * according to the display's visual red_mask, green_mask, and blue_mask.
47 * If XPutPixel is used to put a pixel into an XImage then XPutPixel will
48 * do byte swapping if needed.  If one wants to directly "poke" the pixel
49 * into the XImage's buffer then the pixel must be byte swapped first.  In
50 * Mesa, when byte swapping is needed we use the PF_TRUECOLOR pixel format
51 * and use XPutPixel everywhere except in the implementation of
52 * glClear(GL_COLOR_BUFFER_BIT).  We want this function to be fast so
53 * instead of using XPutPixel we "poke" our values after byte-swapping
54 * the clear pixel value if needed.
55 *
56 */
57
58#ifdef __CYGWIN__
59#undef WIN32
60#undef __WIN32__
61#endif
62
63#include "glxheader.h"
64#include "GL/xmesa.h"
65#include "xmesaP.h"
66#include "context.h"
67#include "extensions.h"
68#include "glthread.h"
69#include "imports.h"
70#include "matrix.h"
71#include "mtypes.h"
72#include "macros.h"
73#include "texformat.h"
74#include "texobj.h"
75#include "texstore.h"
76#include "swrast/swrast.h"
77#include "swrast_setup/swrast_setup.h"
78#include "array_cache/acache.h"
79#include "tnl/tnl.h"
80#include "tnl/t_context.h"
81#include "tnl/t_pipeline.h"
82#include "drivers/common/driverfuncs.h"
83
84#ifdef XFree86Server
85#include <GL/glxtokens.h>
86#endif
87
88/*
89 * Global X driver lock
90 */
91_glthread_Mutex _xmesa_lock;
92
93
94
95/*
96 * Lookup tables for HPCR pixel format:
97 */
98static short hpcr_rgbTbl[3][256] = {
99{
100 16,  16,  17,  17,  18,  18,  19,  19,  20,  20,  21,  21,  22,  22,  23,  23,
101 24,  24,  25,  25,  26,  26,  27,  27,  28,  28,  29,  29,  30,  30,  31,  31,
102 32,  32,  33,  33,  34,  34,  35,  35,  36,  36,  37,  37,  38,  38,  39,  39,
103 32,  33,  34,  35,  36,  37,  38,  39,  40,  41,  42,  43,  44,  45,  46,  47,
104 48,  49,  50,  51,  52,  53,  54,  55,  56,  57,  58,  59,  60,  61,  62,  63,
105 64,  65,  66,  67,  68,  69,  70,  71,  72,  73,  74,  75,  76,  77,  78,  79,
106 80,  81,  82,  83,  84,  85,  86,  87,  88,  89,  90,  91,  92,  93,  94,  95,
107 96,  97,  98,  99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111,
108112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127,
109128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143,
110144, 145, 146, 147, 148, 149, 150, 151, 152, 153, 154, 155, 156, 157, 158, 159,
111160, 161, 162, 163, 164, 165, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175,
112176, 177, 178, 179, 180, 181, 182, 183, 184, 185, 186, 187, 188, 189, 190, 191,
113192, 193, 194, 195, 196, 197, 198, 199, 200, 201, 202, 203, 204, 205, 206, 207,
114208, 209, 210, 211, 212, 213, 214, 215, 216, 217, 218, 219, 220, 221, 222, 223,
115224, 225, 226, 227, 228, 229, 230, 231, 232, 233, 234, 235, 236, 237, 238, 239
116},
117{
118 16,  16,  17,  17,  18,  18,  19,  19,  20,  20,  21,  21,  22,  22,  23,  23,
119 24,  24,  25,  25,  26,  26,  27,  27,  28,  28,  29,  29,  30,  30,  31,  31,
120 32,  32,  33,  33,  34,  34,  35,  35,  36,  36,  37,  37,  38,  38,  39,  39,
121 32,  33,  34,  35,  36,  37,  38,  39,  40,  41,  42,  43,  44,  45,  46,  47,
122 48,  49,  50,  51,  52,  53,  54,  55,  56,  57,  58,  59,  60,  61,  62,  63,
123 64,  65,  66,  67,  68,  69,  70,  71,  72,  73,  74,  75,  76,  77,  78,  79,
124 80,  81,  82,  83,  84,  85,  86,  87,  88,  89,  90,  91,  92,  93,  94,  95,
125 96,  97,  98,  99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111,
126112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127,
127128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143,
128144, 145, 146, 147, 148, 149, 150, 151, 152, 153, 154, 155, 156, 157, 158, 159,
129160, 161, 162, 163, 164, 165, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175,
130176, 177, 178, 179, 180, 181, 182, 183, 184, 185, 186, 187, 188, 189, 190, 191,
131192, 193, 194, 195, 196, 197, 198, 199, 200, 201, 202, 203, 204, 205, 206, 207,
132208, 209, 210, 211, 212, 213, 214, 215, 216, 217, 218, 219, 220, 221, 222, 223,
133224, 225, 226, 227, 228, 229, 230, 231, 232, 233, 234, 235, 236, 237, 238, 239
134},
135{
136 32,  32,  33,  33,  34,  34,  35,  35,  36,  36,  37,  37,  38,  38,  39,  39,
137 40,  40,  41,  41,  42,  42,  43,  43,  44,  44,  45,  45,  46,  46,  47,  47,
138 48,  48,  49,  49,  50,  50,  51,  51,  52,  52,  53,  53,  54,  54,  55,  55,
139 56,  56,  57,  57,  58,  58,  59,  59,  60,  60,  61,  61,  62,  62,  63,  63,
140 64,  64,  65,  65,  66,  66,  67,  67,  68,  68,  69,  69,  70,  70,  71,  71,
141 72,  72,  73,  73,  74,  74,  75,  75,  76,  76,  77,  77,  78,  78,  79,  79,
142 80,  80,  81,  81,  82,  82,  83,  83,  84,  84,  85,  85,  86,  86,  87,  87,
143 80,  81,  82,  83,  84,  85,  86,  87,  88,  89,  90,  91,  92,  93,  94,  95,
144 96,  97,  98,  99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111,
145112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127,
146128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143,
147144, 145, 146, 147, 148, 149, 150, 151, 152, 153, 154, 155, 156, 157, 158, 159,
148160, 161, 162, 163, 164, 165, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175,
149176, 177, 178, 179, 180, 181, 182, 183, 184, 185, 186, 187, 188, 189, 190, 191,
150192, 193, 194, 195, 196, 197, 198, 199, 200, 201, 202, 203, 204, 205, 206, 207,
151208, 209, 210, 211, 212, 213, 214, 215, 216, 217, 218, 219, 220, 221, 222, 223
152}
153};
154
155
156
157/**********************************************************************/
158/*****                     X Utility Functions                    *****/
159/**********************************************************************/
160
161
162/*
163 * Return the host's byte order as LSBFirst or MSBFirst ala X.
164 */
165#ifndef XFree86Server
166static int host_byte_order( void )
167{
168   int i = 1;
169   char *cptr = (char *) &i;
170   return (*cptr==1) ? LSBFirst : MSBFirst;
171}
172#endif
173
174
175/*
176 * Error handling.
177 */
178#ifndef XFree86Server
179static volatile int mesaXErrorFlag = 0;
180
181static int mesaHandleXError( XMesaDisplay *dpy, XErrorEvent *event )
182{
183   (void) dpy;
184   (void) event;
185   mesaXErrorFlag = 1;
186   return 0;
187}
188#endif
189
190
191/*
192 * Check if the X Shared Memory extension is available.
193 * Return:  0 = not available
194 *          1 = shared XImage support available
195 *          2 = shared Pixmap support available also
196 */
197#ifndef XFree86Server
198static int check_for_xshm( XMesaDisplay *display )
199{
200#ifdef USE_XSHM
201   int major, minor, ignore;
202   Bool pixmaps;
203
204   if (XQueryExtension( display, "MIT-SHM", &ignore, &ignore, &ignore )) {
205      if (XShmQueryVersion( display, &major, &minor, &pixmaps )==True) {
206	 return (pixmaps==True) ? 2 : 1;
207      }
208      else {
209	 return 0;
210      }
211   }
212   else {
213      return 0;
214   }
215#else
216   /* Can't compile XSHM support */
217   return 0;
218#endif
219}
220#endif
221
222
223/*
224 * Return the width and height of the given drawable.
225 */
226static void get_drawable_size( XMesaDisplay *dpy, XMesaDrawable d,
227                               unsigned int *width, unsigned int *height)
228{
229#ifdef XFree86Server
230    (void) dpy;
231    *width = d->width;
232    *height = d->height;
233#else
234   Window root;
235   int x, y;
236   unsigned int bw, depth;
237
238   _glthread_LOCK_MUTEX(_xmesa_lock);
239   XGetGeometry( dpy, d, &root, &x, &y, width, height, &bw, &depth );
240   _glthread_UNLOCK_MUTEX(_xmesa_lock);
241#endif
242}
243
244
245/*
246 * Apply gamma correction to an intensity value in [0..max].  Return the
247 * new intensity value.
248 */
249static GLint gamma_adjust( GLfloat gamma, GLint value, GLint max )
250{
251   if (gamma == 1.0) {
252      return value;
253   }
254   else {
255      double x = (double) value / (double) max;
256      return IROUND_POS((GLfloat) max * _mesa_pow(x, 1.0F/gamma));
257   }
258}
259
260
261
262/*
263 * Return the true number of bits per pixel for XImages.
264 * For example, if we request a 24-bit deep visual we may actually need/get
265 * 32bpp XImages.  This function returns the appropriate bpp.
266 * Input:  dpy - the X display
267 *         visinfo - desribes the visual to be used for XImages
268 * Return:  true number of bits per pixel for XImages
269 */
270#ifdef XFree86Server
271
272static int bits_per_pixel( XMesaVisual xmv )
273{
274   const int depth = xmv->nplanes;
275   int i;
276   for (i = 0; i < screenInfo.numPixmapFormats; i++) {
277      if (screenInfo.formats[i].depth == depth)
278         return screenInfo.formats[i].bitsPerPixel;
279   }
280   return depth;  /* should never get here, but this should be safe */
281}
282
283#else
284
285static int bits_per_pixel( XMesaVisual xmv )
286{
287   XMesaDisplay *dpy = xmv->display;
288   XMesaVisualInfo visinfo = xmv->visinfo;
289   XMesaImage *img;
290   int bitsPerPixel;
291   /* Create a temporary XImage */
292   img = XCreateImage( dpy, visinfo->visual, visinfo->depth,
293		       ZPixmap, 0,           /*format, offset*/
294		       (char*) MALLOC(8),    /*data*/
295		       1, 1,                 /*width, height*/
296		       32,                   /*bitmap_pad*/
297		       0                     /*bytes_per_line*/
298                     );
299   assert(img);
300   /* grab the bits/pixel value */
301   bitsPerPixel = img->bits_per_pixel;
302   /* free the XImage */
303   FREE( img->data );
304   img->data = NULL;
305   XMesaDestroyImage( img );
306   return bitsPerPixel;
307}
308#endif
309
310
311
312/*
313 * Determine if a given X window ID is valid (window exists).
314 * Do this by calling XGetWindowAttributes() for the window and
315 * checking if we catch an X error.
316 * Input:  dpy - the display
317 *         win - the window to check for existance
318 * Return:  GL_TRUE - window exists
319 *          GL_FALSE - window doesn't exist
320 */
321#ifndef XFree86Server
322static GLboolean WindowExistsFlag;
323
324static int window_exists_err_handler( XMesaDisplay* dpy, XErrorEvent* xerr )
325{
326   (void) dpy;
327   if (xerr->error_code == BadWindow) {
328      WindowExistsFlag = GL_FALSE;
329   }
330   return 0;
331}
332
333static GLboolean window_exists( XMesaDisplay *dpy, Window win )
334{
335   XWindowAttributes wa;
336   int (*old_handler)( XMesaDisplay*, XErrorEvent* );
337   WindowExistsFlag = GL_TRUE;
338   old_handler = XSetErrorHandler(window_exists_err_handler);
339   XGetWindowAttributes( dpy, win, &wa ); /* dummy request */
340   XSetErrorHandler(old_handler);
341   return WindowExistsFlag;
342}
343#endif
344
345
346
347/**********************************************************************/
348/*****                Linked list of XMesaBuffers                 *****/
349/**********************************************************************/
350
351static XMesaBuffer XMesaBufferList = NULL;
352
353
354/* Allocate a new XMesaBuffer, add to linked list */
355static XMesaBuffer alloc_xmesa_buffer(void)
356{
357   XMesaBuffer b = (XMesaBuffer) CALLOC_STRUCT(xmesa_buffer);
358   if (b) {
359      b->Next = XMesaBufferList;
360      XMesaBufferList = b;
361   }
362   return b;
363}
364
365
366/*
367 * Find an XMesaBuffer by matching X display and colormap but NOT matching
368 * the notThis buffer.
369 */
370static XMesaBuffer find_xmesa_buffer(XMesaDisplay *dpy,
371                                     XMesaColormap cmap,
372                                     XMesaBuffer notThis)
373{
374   XMesaBuffer b;
375   for (b=XMesaBufferList; b; b=b->Next) {
376      if (b->display==dpy && b->cmap==cmap && b!=notThis) {
377         return b;
378      }
379   }
380   return NULL;
381}
382
383
384/*
385 * Free an XMesaBuffer, remove from linked list, perhaps free X colormap
386 * entries.
387 */
388static void free_xmesa_buffer(int client, XMesaBuffer buffer)
389{
390   XMesaBuffer prev = NULL, b;
391   (void) client;
392   for (b=XMesaBufferList; b; b=b->Next) {
393      if (b==buffer) {
394         /* unlink bufer from list */
395         if (prev)
396            prev->Next = buffer->Next;
397         else
398            XMesaBufferList = buffer->Next;
399         /* Check to free X colors */
400         if (buffer->num_alloced>0) {
401            /* If no other buffer uses this X colormap then free the colors. */
402            if (!find_xmesa_buffer(buffer->display, buffer->cmap, buffer)) {
403#ifdef XFree86Server
404               (void)FreeColors(buffer->cmap, client,
405				buffer->num_alloced, buffer->alloced_colors,
406				0);
407#else
408               XFreeColors(buffer->display, buffer->cmap,
409                           buffer->alloced_colors, buffer->num_alloced, 0);
410#endif
411            }
412         }
413
414         _mesa_free_framebuffer_data(&buffer->mesa_buffer);
415         FREE(buffer);
416
417         return;
418      }
419      /* continue search */
420      prev = b;
421   }
422   /* buffer not found in XMesaBufferList */
423   _mesa_problem(NULL,"free_xmesa_buffer() - buffer not found\n");
424}
425
426
427/* Copy X color table stuff from one XMesaBuffer to another. */
428static void copy_colortable_info(XMesaBuffer dst, const XMesaBuffer src)
429{
430   MEMCPY(dst->color_table, src->color_table, sizeof(src->color_table));
431   MEMCPY(dst->pixel_to_r, src->pixel_to_r, sizeof(src->pixel_to_r));
432   MEMCPY(dst->pixel_to_g, src->pixel_to_g, sizeof(src->pixel_to_g));
433   MEMCPY(dst->pixel_to_b, src->pixel_to_b, sizeof(src->pixel_to_b));
434   dst->num_alloced = src->num_alloced;
435   MEMCPY(dst->alloced_colors, src->alloced_colors,
436          sizeof(src->alloced_colors));
437}
438
439
440
441/**********************************************************************/
442/*****                   Misc Private Functions                   *****/
443/**********************************************************************/
444
445
446/*
447 * Return number of bits set in n.
448 */
449static int bitcount( unsigned long n )
450{
451   int bits;
452   for (bits=0; n>0; n=n>>1) {
453      if (n&1) {
454         bits++;
455      }
456   }
457   return bits;
458}
459
460
461
462/*
463 * Allocate a shared memory XImage back buffer for the given XMesaBuffer.
464 * Return:  GL_TRUE if success, GL_FALSE if error
465 */
466#ifndef XFree86Server
467static GLboolean alloc_shm_back_buffer( XMesaBuffer b )
468{
469#ifdef USE_XSHM
470   /*
471    * We have to do a _lot_ of error checking here to be sure we can
472    * really use the XSHM extension.  It seems different servers trigger
473    * errors at different points if the extension won't work.  Therefore
474    * we have to be very careful...
475    */
476   GC gc;
477   int (*old_handler)( XMesaDisplay *, XErrorEvent * );
478
479   b->backimage = XShmCreateImage( b->xm_visual->display,
480                                   b->xm_visual->visinfo->visual,
481                                   b->xm_visual->visinfo->depth,
482				   ZPixmap, NULL, &b->shminfo,
483				   b->width, b->height );
484   if (b->backimage == NULL) {
485      _mesa_warning(NULL, "alloc_back_buffer: Shared memory error (XShmCreateImage), disabling.");
486      b->shm = 0;
487      return GL_FALSE;
488   }
489
490   b->shminfo.shmid = shmget( IPC_PRIVATE, b->backimage->bytes_per_line
491			     * b->backimage->height, IPC_CREAT|0777 );
492   if (b->shminfo.shmid < 0) {
493      _mesa_warning(NULL, "shmget failed while allocating back buffer");
494      XDestroyImage( b->backimage );
495      b->backimage = NULL;
496      _mesa_warning(NULL, "alloc_back_buffer: Shared memory error (shmget), disabling.");
497      b->shm = 0;
498      return GL_FALSE;
499   }
500
501   b->shminfo.shmaddr = b->backimage->data
502                      = (char*)shmat( b->shminfo.shmid, 0, 0 );
503   if (b->shminfo.shmaddr == (char *) -1) {
504      _mesa_warning(NULL, "shmat() failed while allocating back buffer");
505      XDestroyImage( b->backimage );
506      shmctl( b->shminfo.shmid, IPC_RMID, 0 );
507      b->backimage = NULL;
508      _mesa_warning(NULL, "alloc_back_buffer: Shared memory error (shmat), disabling.");
509      b->shm = 0;
510      return GL_FALSE;
511   }
512
513   b->shminfo.readOnly = False;
514   mesaXErrorFlag = 0;
515   old_handler = XSetErrorHandler( mesaHandleXError );
516   /* This may trigger the X protocol error we're ready to catch: */
517   XShmAttach( b->xm_visual->display, &b->shminfo );
518   XSync( b->xm_visual->display, False );
519
520   if (mesaXErrorFlag) {
521      /* we are on a remote display, this error is normal, don't print it */
522      XFlush( b->xm_visual->display );
523      mesaXErrorFlag = 0;
524      XDestroyImage( b->backimage );
525      shmdt( b->shminfo.shmaddr );
526      shmctl( b->shminfo.shmid, IPC_RMID, 0 );
527      b->backimage = NULL;
528      b->shm = 0;
529      (void) XSetErrorHandler( old_handler );
530      return GL_FALSE;
531   }
532
533   shmctl( b->shminfo.shmid, IPC_RMID, 0 ); /* nobody else needs it */
534
535   /* Finally, try an XShmPutImage to be really sure the extension works */
536   gc = XCreateGC( b->xm_visual->display, b->frontbuffer, 0, NULL );
537   XShmPutImage( b->xm_visual->display, b->frontbuffer, gc,
538		 b->backimage, 0, 0, 0, 0, 1, 1 /*one pixel*/, False );
539   XSync( b->xm_visual->display, False );
540   XFreeGC( b->xm_visual->display, gc );
541   (void) XSetErrorHandler( old_handler );
542   if (mesaXErrorFlag) {
543      XFlush( b->xm_visual->display );
544      mesaXErrorFlag = 0;
545      XDestroyImage( b->backimage );
546      shmdt( b->shminfo.shmaddr );
547      shmctl( b->shminfo.shmid, IPC_RMID, 0 );
548      b->backimage = NULL;
549      b->shm = 0;
550      return GL_FALSE;
551   }
552
553   if (b->backimage) {
554      int height = b->backimage->height;
555      /* Needed by PIXELADDR1 macro */
556      b->ximage_width1 = b->backimage->bytes_per_line;
557      b->ximage_origin1 = (GLubyte *) b->backimage->data
558                        + b->ximage_width1 * (height-1);
559      /* Needed by PIXELADDR2 macro */
560      b->ximage_width2 = b->backimage->bytes_per_line / 2;
561      b->ximage_origin2 = (GLushort *) b->backimage->data
562                        + b->ximage_width2 * (height-1);
563      /* Needed by PIXELADDR3 macro */
564      b->ximage_width3 = b->backimage->bytes_per_line;
565      b->ximage_origin3 = (GLubyte *) b->backimage->data
566                        + b->ximage_width3 * (height-1);
567      /* Needed by PIXELADDR4 macro */
568      b->ximage_width4 = b->backimage->width;
569      b->ximage_origin4 = (GLuint *) b->backimage->data
570                        + b->ximage_width4 * (height-1);
571   }
572
573   return GL_TRUE;
574#else
575   /* Can't compile XSHM support */
576   return GL_FALSE;
577#endif
578}
579#endif
580
581
582
583/*
584 * Setup an off-screen pixmap or Ximage to use as the back buffer.
585 * Input:  b - the X/Mesa buffer
586 */
587void xmesa_alloc_back_buffer( XMesaBuffer b )
588{
589   if (b->db_state==BACK_XIMAGE) {
590      /* Deallocate the old backimage, if any */
591      if (b->backimage) {
592#if defined(USE_XSHM) && !defined(XFree86Server)
593	 if (b->shm) {
594	    XShmDetach( b->xm_visual->display, &b->shminfo );
595	    XDestroyImage( b->backimage );
596	    shmdt( b->shminfo.shmaddr );
597	 }
598	 else
599#endif
600	   XMesaDestroyImage( b->backimage );
601	 b->backimage = NULL;
602      }
603
604      /* Allocate new back buffer */
605#ifdef XFree86Server
606      {
607	 /* Allocate a regular XImage for the back buffer. */
608	 b->backimage = XMesaCreateImage(b->xm_visual->BitsPerPixel,
609					 b->width, b->height, NULL);
610#else
611      if (b->shm==0 || alloc_shm_back_buffer(b)==GL_FALSE) {
612	 /* Allocate a regular XImage for the back buffer. */
613	 b->backimage = XCreateImage( b->xm_visual->display,
614                                      b->xm_visual->visinfo->visual,
615                                      GET_VISUAL_DEPTH(b->xm_visual),
616				      ZPixmap, 0,   /* format, offset */
617				      NULL, b->width, b->height,
618				      8, 0 );  /* pad, bytes_per_line */
619#endif
620	 if (!b->backimage) {
621	    _mesa_warning(NULL, "alloc_back_buffer: XCreateImage failed.");
622	 }
623         b->backimage->data = (char *) MALLOC( b->backimage->height
624                                             * b->backimage->bytes_per_line );
625         if (!b->backimage->data) {
626            _mesa_warning(NULL, "alloc_back_buffer: MALLOC failed.");
627            XMesaDestroyImage( b->backimage );
628            b->backimage = NULL;
629         }
630      }
631      b->backpixmap = None;
632   }
633   else if (b->db_state==BACK_PIXMAP) {
634      XMesaPixmap old_pixmap = b->backpixmap;
635      /* Free the old back pixmap */
636      if (b->backpixmap) {
637	 XMesaFreePixmap( b->xm_visual->display, b->backpixmap );
638      }
639      /* Allocate new back pixmap */
640      b->backpixmap = XMesaCreatePixmap( b->xm_visual->display, b->frontbuffer,
641					 b->width, b->height,
642					 GET_VISUAL_DEPTH(b->xm_visual) );
643      b->backimage = NULL;
644      /* update other references to backpixmap */
645      if (b->buffer==(XMesaDrawable)old_pixmap) {
646	 b->buffer = (XMesaDrawable)b->backpixmap;
647      }
648   }
649}
650
651
652
653/*
654 * A replacement for XAllocColor.  This function should never
655 * fail to allocate a color.  When XAllocColor fails, we return
656 * the nearest matching color.  If we have to allocate many colors
657 * this function isn't too efficient; the XQueryColors() could be
658 * done just once.
659 * Written by Michael Pichler, Brian Paul, Mark Kilgard
660 * Input:  dpy - X display
661 *         cmap - X colormap
662 *         cmapSize - size of colormap
663 * In/Out: color - the XColor struct
664 * Output:  exact - 1=exact color match, 0=closest match
665 *          alloced - 1=XAlloc worked, 0=XAlloc failed
666 */
667static void
668noFaultXAllocColor( int client,
669                    XMesaDisplay *dpy,
670                    XMesaColormap cmap,
671                    int cmapSize,
672                    XMesaColor *color,
673                    int *exact, int *alloced )
674{
675#ifdef XFree86Server
676   Pixel *ppixIn;
677   xrgb *ctable;
678#else
679   /* we'll try to cache ctable for better remote display performance */
680   static Display *prevDisplay = NULL;
681   static XMesaColormap prevCmap = 0;
682   static int prevCmapSize = 0;
683   static XMesaColor *ctable = NULL;
684#endif
685   XMesaColor subColor;
686   int i, bestmatch;
687   double mindist;       /* 3*2^16^2 exceeds long int precision. */
688
689   (void) client;
690
691   /* First try just using XAllocColor. */
692#ifdef XFree86Server
693   if (AllocColor(cmap,
694		  &color->red, &color->green, &color->blue,
695		  &color->pixel,
696		  client) == Success) {
697#else
698   if (XAllocColor(dpy, cmap, color)) {
699#endif
700      *exact = 1;
701      *alloced = 1;
702      return;
703   }
704
705   /* Alloc failed, search for closest match */
706
707   /* Retrieve color table entries. */
708   /* XXX alloca candidate. */
709#ifdef XFree86Server
710   ppixIn = (Pixel *) MALLOC(cmapSize * sizeof(Pixel));
711   ctable = (xrgb *) MALLOC(cmapSize * sizeof(xrgb));
712   for (i = 0; i < cmapSize; i++) {
713      ppixIn[i] = i;
714   }
715   QueryColors(cmap, cmapSize, ppixIn, ctable);
716#else
717   if (prevDisplay != dpy || prevCmap != cmap
718       || prevCmapSize != cmapSize || !ctable) {
719      /* free previously cached color table */
720      if (ctable)
721         FREE(ctable);
722      /* Get the color table from X */
723      ctable = (XMesaColor *) MALLOC(cmapSize * sizeof(XMesaColor));
724      assert(ctable);
725      for (i = 0; i < cmapSize; i++) {
726         ctable[i].pixel = i;
727      }
728      XQueryColors(dpy, cmap, ctable, cmapSize);
729      prevDisplay = dpy;
730      prevCmap = cmap;
731      prevCmapSize = cmapSize;
732   }
733#endif
734
735   /* Find best match. */
736   bestmatch = -1;
737   mindist = 0.0;
738   for (i = 0; i < cmapSize; i++) {
739      double dr = 0.30 * ((double) color->red - (double) ctable[i].red);
740      double dg = 0.59 * ((double) color->green - (double) ctable[i].green);
741      double db = 0.11 * ((double) color->blue - (double) ctable[i].blue);
742      double dist = dr * dr + dg * dg + db * db;
743      if (bestmatch < 0 || dist < mindist) {
744         bestmatch = i;
745         mindist = dist;
746      }
747   }
748
749   /* Return result. */
750   subColor.red   = ctable[bestmatch].red;
751   subColor.green = ctable[bestmatch].green;
752   subColor.blue  = ctable[bestmatch].blue;
753   /* Try to allocate the closest match color.  This should only
754    * fail if the cell is read/write.  Otherwise, we're incrementing
755    * the cell's reference count.
756    */
757#ifdef XFree86Server
758   if (AllocColor(cmap,
759		  &subColor.red, &subColor.green, &subColor.blue,
760		  &subColor.pixel,
761		  client) == Success) {
762#else
763   if (XAllocColor(dpy, cmap, &subColor)) {
764#endif
765      *alloced = 1;
766   }
767   else {
768      /* do this to work around a problem reported by Frank Ortega */
769      subColor.pixel = (unsigned long) bestmatch;
770      subColor.red   = ctable[bestmatch].red;
771      subColor.green = ctable[bestmatch].green;
772      subColor.blue  = ctable[bestmatch].blue;
773      subColor.flags = DoRed | DoGreen | DoBlue;
774      *alloced = 0;
775   }
776#ifdef XFree86Server
777   FREE(ppixIn);
778   FREE(ctable);
779#else
780   /* don't free table, save it for next time */
781#endif
782
783   *color = subColor;
784   *exact = 0;
785}
786
787
788
789
790/*
791 * Do setup for PF_GRAYSCALE pixel format.
792 * Note that buffer may be NULL.
793 */
794static GLboolean setup_grayscale( int client, XMesaVisual v,
795                                  XMesaBuffer buffer, XMesaColormap cmap )
796{
797   if (GET_VISUAL_DEPTH(v)<4 || GET_VISUAL_DEPTH(v)>16) {
798      return GL_FALSE;
799   }
800
801   if (buffer) {
802      XMesaBuffer prevBuffer;
803
804      if (!cmap) {
805         return GL_FALSE;
806      }
807
808      prevBuffer = find_xmesa_buffer(v->display, cmap, buffer);
809      if (prevBuffer &&
810          (buffer->xm_visual->mesa_visual.rgbMode ==
811           prevBuffer->xm_visual->mesa_visual.rgbMode)) {
812         /* Copy colormap stuff from previous XMesaBuffer which uses same
813          * X colormap.  Do this to avoid time spent in noFaultXAllocColor.
814          */
815         copy_colortable_info(buffer, prevBuffer);
816      }
817      else {
818         /* Allocate 256 shades of gray */
819         int gray;
820         int colorsfailed = 0;
821         for (gray=0;gray<256;gray++) {
822            GLint r = gamma_adjust( v->RedGamma,   gray, 255 );
823            GLint g = gamma_adjust( v->GreenGamma, gray, 255 );
824            GLint b = gamma_adjust( v->BlueGamma,  gray, 255 );
825            int exact, alloced;
826            XMesaColor xcol;
827            xcol.red   = (r << 8) | r;
828            xcol.green = (g << 8) | g;
829            xcol.blue  = (b << 8) | b;
830            noFaultXAllocColor( client, v->display,
831                                cmap, GET_COLORMAP_SIZE(v),
832                                &xcol, &exact, &alloced );
833            if (!exact) {
834               colorsfailed++;
835            }
836            if (alloced) {
837               assert(buffer->num_alloced<256);
838               buffer->alloced_colors[buffer->num_alloced] = xcol.pixel;
839               buffer->num_alloced++;
840            }
841
842            /*OLD
843            assert(gray < 576);
844            buffer->color_table[gray*3+0] = xcol.pixel;
845            buffer->color_table[gray*3+1] = xcol.pixel;
846            buffer->color_table[gray*3+2] = xcol.pixel;
847            assert(xcol.pixel < 65536);
848            buffer->pixel_to_r[xcol.pixel] = gray * 30 / 100;
849            buffer->pixel_to_g[xcol.pixel] = gray * 59 / 100;
850            buffer->pixel_to_b[xcol.pixel] = gray * 11 / 100;
851            */
852            buffer->color_table[gray] = xcol.pixel;
853            assert(xcol.pixel < 65536);
854            buffer->pixel_to_r[xcol.pixel] = gray;
855            buffer->pixel_to_g[xcol.pixel] = gray;
856            buffer->pixel_to_b[xcol.pixel] = gray;
857         }
858
859         if (colorsfailed && _mesa_getenv("MESA_DEBUG")) {
860            _mesa_warning(NULL,
861                  "Note: %d out of 256 needed colors do not match exactly.\n",
862                  colorsfailed );
863         }
864      }
865   }
866
867   v->dithered_pf = PF_Grayscale;
868   v->undithered_pf = PF_Grayscale;
869   return GL_TRUE;
870}
871
872
873
874/*
875 * Setup RGB rendering for a window with a PseudoColor, StaticColor,
876 * or 8-bit TrueColor visual visual.  We try to allocate a palette of 225
877 * colors (5 red, 9 green, 5 blue) and dither to approximate a 24-bit RGB
878 * color.  While this function was originally designed just for 8-bit
879 * visuals, it has also proven to work from 4-bit up to 16-bit visuals.
880 * Dithering code contributed by Bob Mercier.
881 */
882static GLboolean setup_dithered_color( int client, XMesaVisual v,
883                                       XMesaBuffer buffer, XMesaColormap cmap )
884{
885   if (GET_VISUAL_DEPTH(v)<4 || GET_VISUAL_DEPTH(v)>16) {
886      return GL_FALSE;
887   }
888
889   if (buffer) {
890      XMesaBuffer prevBuffer;
891
892      if (!cmap) {
893         return GL_FALSE;
894      }
895
896      prevBuffer = find_xmesa_buffer(v->display, cmap, buffer);
897      if (prevBuffer &&
898          (buffer->xm_visual->mesa_visual.rgbMode ==
899           prevBuffer->xm_visual->mesa_visual.rgbMode)) {
900         /* Copy colormap stuff from previous, matching XMesaBuffer.
901          * Do this to avoid time spent in noFaultXAllocColor.
902          */
903         copy_colortable_info(buffer, prevBuffer);
904      }
905      else {
906         /* Allocate X colors and initialize color_table[], red_table[], etc */
907         int r, g, b, i;
908         int colorsfailed = 0;
909         for (r = 0; r < DITH_R; r++) {
910            for (g = 0; g < DITH_G; g++) {
911               for (b = 0; b < DITH_B; b++) {
912                  XMesaColor xcol;
913                  int exact, alloced;
914                  xcol.red  =gamma_adjust(v->RedGamma,   r*65535/(DITH_R-1),65535);
915                  xcol.green=gamma_adjust(v->GreenGamma, g*65535/(DITH_G-1),65535);
916                  xcol.blue =gamma_adjust(v->BlueGamma,  b*65535/(DITH_B-1),65535);
917                  noFaultXAllocColor( client, v->display,
918                                      cmap, GET_COLORMAP_SIZE(v),
919                                      &xcol, &exact, &alloced );
920                  if (!exact) {
921                     colorsfailed++;
922                  }
923                  if (alloced) {
924                     assert(buffer->num_alloced<256);
925                     buffer->alloced_colors[buffer->num_alloced] = xcol.pixel;
926                     buffer->num_alloced++;
927                  }
928                  i = DITH_MIX( r, g, b );
929                  assert(i < 576);
930                  buffer->color_table[i] = xcol.pixel;
931                  assert(xcol.pixel < 65536);
932                  buffer->pixel_to_r[xcol.pixel] = r * 255 / (DITH_R-1);
933                  buffer->pixel_to_g[xcol.pixel] = g * 255 / (DITH_G-1);
934                  buffer->pixel_to_b[xcol.pixel] = b * 255 / (DITH_B-1);
935               }
936            }
937         }
938
939         if (colorsfailed && _mesa_getenv("MESA_DEBUG")) {
940            _mesa_warning(NULL,
941                  "Note: %d out of %d needed colors do not match exactly.\n",
942                  colorsfailed, DITH_R * DITH_G * DITH_B );
943         }
944      }
945   }
946
947   v->dithered_pf = PF_Dither;
948   v->undithered_pf = PF_Lookup;
949   return GL_TRUE;
950}
951
952
953/*
954 * Setup for Hewlett Packard Color Recovery 8-bit TrueColor mode.
955 * HPCR simulates 24-bit color fidelity with an 8-bit frame buffer.
956 * Special dithering tables have to be initialized.
957 */
958static void setup_8bit_hpcr( XMesaVisual v )
959{
960   /* HP Color Recovery contributed by:  Alex De Bruyn (ad@lms.be)
961    * To work properly, the atom _HP_RGB_SMOOTH_MAP_LIST must be defined
962    * on the root window AND the colormap obtainable by XGetRGBColormaps
963    * for that atom must be set on the window.  (see also tkInitWindow)
964    * If that colormap is not set, the output will look stripy.
965    */
966
967   /* Setup color tables with gamma correction */
968   int i;
969   double g;
970
971   g = 1.0 / v->RedGamma;
972   for (i=0; i<256; i++) {
973      GLint red = IROUND_POS(255.0 * _mesa_pow( hpcr_rgbTbl[0][i]/255.0, g ));
974      v->hpcr_rgbTbl[0][i] = CLAMP( red, 16, 239 );
975   }
976
977   g = 1.0 / v->GreenGamma;
978   for (i=0; i<256; i++) {
979      GLint green = IROUND_POS(255.0 * _mesa_pow( hpcr_rgbTbl[1][i]/255.0, g ));
980      v->hpcr_rgbTbl[1][i] = CLAMP( green, 16, 239 );
981   }
982
983   g = 1.0 / v->BlueGamma;
984   for (i=0; i<256; i++) {
985      GLint blue = IROUND_POS(255.0 * _mesa_pow( hpcr_rgbTbl[2][i]/255.0, g ));
986      v->hpcr_rgbTbl[2][i] = CLAMP( blue, 32, 223 );
987   }
988   v->undithered_pf = PF_HPCR;  /* can't really disable dithering for now */
989   v->dithered_pf = PF_HPCR;
990
991   /* which method should I use to clear */
992   /* GL_FALSE: keep the ordinary method  */
993   /* GL_TRUE : clear with dither pattern */
994   v->hpcr_clear_flag = _mesa_getenv("MESA_HPCR_CLEAR") ? GL_TRUE : GL_FALSE;
995
996   if (v->hpcr_clear_flag) {
997      v->hpcr_clear_pixmap = XMesaCreatePixmap(v->display,
998                                               DefaultRootWindow(v->display),
999                                               16, 2, 8);
1000#ifndef XFree86Server
1001      v->hpcr_clear_ximage = XGetImage(v->display, v->hpcr_clear_pixmap,
1002                                       0, 0, 16, 2, AllPlanes, ZPixmap);
1003#endif
1004   }
1005}
1006
1007
1008/*
1009 * Setup RGB rendering for a window with a True/DirectColor visual.
1010 */
1011static void setup_truecolor( XMesaVisual v, XMesaBuffer buffer,
1012                             XMesaColormap cmap )
1013{
1014   unsigned long rmask, gmask, bmask;
1015   (void) buffer;
1016   (void) cmap;
1017
1018   /* Compute red multiplier (mask) and bit shift */
1019   v->rshift = 0;
1020   rmask = GET_REDMASK(v);
1021   while ((rmask & 1)==0) {
1022      v->rshift++;
1023      rmask = rmask >> 1;
1024   }
1025
1026   /* Compute green multiplier (mask) and bit shift */
1027   v->gshift = 0;
1028   gmask = GET_GREENMASK(v);
1029   while ((gmask & 1)==0) {
1030      v->gshift++;
1031      gmask = gmask >> 1;
1032   }
1033
1034   /* Compute blue multiplier (mask) and bit shift */
1035   v->bshift = 0;
1036   bmask = GET_BLUEMASK(v);
1037   while ((bmask & 1)==0) {
1038      v->bshift++;
1039      bmask = bmask >> 1;
1040   }
1041
1042   /*
1043    * Compute component-to-pixel lookup tables and dithering kernel
1044    */
1045   {
1046      static GLubyte kernel[16] = {
1047          0*16,  8*16,  2*16, 10*16,
1048         12*16,  4*16, 14*16,  6*16,
1049          3*16, 11*16,  1*16,  9*16,
1050         15*16,  7*16, 13*16,  5*16,
1051      };
1052      GLint rBits = bitcount(rmask);
1053      GLint gBits = bitcount(gmask);
1054      GLint bBits = bitcount(bmask);
1055      GLint maxBits;
1056      GLuint i;
1057
1058      /* convert pixel components in [0,_mask] to RGB values in [0,255] */
1059      for (i=0; i<=rmask; i++)
1060         v->PixelToR[i] = (unsigned char) ((i * 255) / rmask);
1061      for (i=0; i<=gmask; i++)
1062         v->PixelToG[i] = (unsigned char) ((i * 255) / gmask);
1063      for (i=0; i<=bmask; i++)
1064         v->PixelToB[i] = (unsigned char) ((i * 255) / bmask);
1065
1066      /* convert RGB values from [0,255] to pixel components */
1067
1068      for (i=0;i<256;i++) {
1069         GLint r = gamma_adjust(v->RedGamma,   i, 255);
1070         GLint g = gamma_adjust(v->GreenGamma, i, 255);
1071         GLint b = gamma_adjust(v->BlueGamma,  i, 255);
1072         v->RtoPixel[i] = (r >> (8-rBits)) << v->rshift;
1073         v->GtoPixel[i] = (g >> (8-gBits)) << v->gshift;
1074         v->BtoPixel[i] = (b >> (8-bBits)) << v->bshift;
1075      }
1076      /* overflow protection */
1077      for (i=256;i<512;i++) {
1078         v->RtoPixel[i] = v->RtoPixel[255];
1079         v->GtoPixel[i] = v->GtoPixel[255];
1080         v->BtoPixel[i] = v->BtoPixel[255];
1081      }
1082
1083      /* setup dithering kernel */
1084      maxBits = rBits;
1085      if (gBits > maxBits)  maxBits = gBits;
1086      if (bBits > maxBits)  maxBits = bBits;
1087      for (i=0;i<16;i++) {
1088         v->Kernel[i] = kernel[i] >> maxBits;
1089      }
1090
1091      v->undithered_pf = PF_Truecolor;
1092      v->dithered_pf = (GET_VISUAL_DEPTH(v)<24) ? PF_Dither_True : PF_Truecolor;
1093   }
1094
1095   /*
1096    * Now check for TrueColor visuals which we can optimize.
1097    */
1098   if (   GET_REDMASK(v)  ==0x0000ff
1099       && GET_GREENMASK(v)==0x00ff00
1100       && GET_BLUEMASK(v) ==0xff0000
1101       && CHECK_BYTE_ORDER(v)
1102       && v->BitsPerPixel==32
1103       && sizeof(GLuint)==4
1104       && v->RedGamma==1.0 && v->GreenGamma==1.0 && v->BlueGamma==1.0) {
1105      /* common 32 bpp config used on SGI, Sun */
1106      v->undithered_pf = v->dithered_pf = PF_8A8B8G8R;
1107   }
1108   else if (GET_REDMASK(v)  ==0xff0000
1109       &&   GET_GREENMASK(v)==0x00ff00
1110       &&   GET_BLUEMASK(v) ==0x0000ff
1111       && CHECK_BYTE_ORDER(v)
1112       && v->BitsPerPixel==32
1113       && sizeof(GLuint)==4
1114       && v->RedGamma==1.0 && v->GreenGamma==1.0 && v->BlueGamma==1.0) {
1115      /* common 32 bpp config used on Linux, HP, IBM */
1116      v->undithered_pf = v->dithered_pf = PF_8R8G8B;
1117   }
1118   else if (GET_REDMASK(v)  ==0xff0000
1119       &&   GET_GREENMASK(v)==0x00ff00
1120       &&   GET_BLUEMASK(v) ==0x0000ff
1121       && CHECK_BYTE_ORDER(v)
1122       && v->BitsPerPixel==24
1123       && sizeof(GLuint)==4
1124       && v->RedGamma==1.0 && v->GreenGamma==1.0 && v->BlueGamma==1.0) {
1125      /* common packed 24 bpp config used on Linux */
1126      v->undithered_pf = v->dithered_pf = PF_8R8G8B24;
1127   }
1128   else if (GET_REDMASK(v)  ==0xf800
1129       &&   GET_GREENMASK(v)==0x07e0
1130       &&   GET_BLUEMASK(v) ==0x001f
1131       && CHECK_BYTE_ORDER(v)
1132       && v->BitsPerPixel==16
1133       && sizeof(GLushort)==2
1134       && v->RedGamma==1.0 && v->GreenGamma==1.0 && v->BlueGamma==1.0) {
1135      /* 5-6-5 color weight on common PC VGA boards */
1136      v->undithered_pf = PF_5R6G5B;
1137      v->dithered_pf = PF_Dither_5R6G5B;
1138   }
1139   else if (GET_REDMASK(v)  ==0xe0
1140       &&   GET_GREENMASK(v)==0x1c
1141       &&   GET_BLUEMASK(v) ==0x03
1142       && CHECK_FOR_HPCR(v)) {
1143      setup_8bit_hpcr( v );
1144   }
1145}
1146
1147
1148
1149/*
1150 * Setup RGB rendering for a window with a monochrome visual.
1151 */
1152static void setup_monochrome( XMesaVisual v, XMesaBuffer b )
1153{
1154   (void) b;
1155   v->dithered_pf = v->undithered_pf = PF_1Bit;
1156   /* if black=1 then we must flip pixel values */
1157   v->bitFlip = (GET_BLACK_PIXEL(v) != 0);
1158}
1159
1160
1161
1162/*
1163 * When a context is "made current" for the first time, we can finally
1164 * finish initializing the context's visual and buffer information.
1165 * Input:  v - the XMesaVisual to initialize
1166 *         b - the XMesaBuffer to initialize (may be NULL)
1167 *         rgb_flag - TRUE = RGBA mode, FALSE = color index mode
1168 *         window - the window/pixmap we're rendering into
1169 *         cmap - the colormap associated with the window/pixmap
1170 * Return:  GL_TRUE=success, GL_FALSE=failure
1171 */
1172static GLboolean initialize_visual_and_buffer( int client,
1173                                               XMesaVisual v,
1174                                               XMesaBuffer b,
1175                                               GLboolean rgb_flag,
1176                                               XMesaDrawable window,
1177                                               XMesaColormap cmap )
1178{
1179#ifndef XFree86Server
1180   XGCValues gcvalues;
1181#endif
1182
1183   if (b) {
1184      assert(b->xm_visual == v);
1185   }
1186
1187   /* Save true bits/pixel */
1188   v->BitsPerPixel = bits_per_pixel(v);
1189   assert(v->BitsPerPixel > 0);
1190
1191
1192   if (rgb_flag==GL_FALSE) {
1193      /* COLOR-INDEXED WINDOW:
1194       * Even if the visual is TrueColor or DirectColor we treat it as
1195       * being color indexed.  This is weird but might be useful to someone.
1196       */
1197      v->dithered_pf = v->undithered_pf = PF_Index;
1198      v->mesa_visual.indexBits = GET_VISUAL_DEPTH(v);
1199   }
1200   else {
1201      /* RGB WINDOW:
1202       * We support RGB rendering into almost any kind of visual.
1203       */
1204      const int xclass = v->mesa_visual.visualType;
1205      if (xclass==GLX_TRUE_COLOR || xclass==GLX_DIRECT_COLOR) {
1206	 setup_truecolor( v, b, cmap );
1207      }
1208      else if (xclass==GLX_STATIC_GRAY && GET_VISUAL_DEPTH(v)==1) {
1209	 setup_monochrome( v, b );
1210      }
1211      else if (xclass==GLX_GRAY_SCALE || xclass==GLX_STATIC_GRAY) {
1212         if (!setup_grayscale( client, v, b, cmap )) {
1213            return GL_FALSE;
1214         }
1215      }
1216      else if ((xclass==GLX_PSEUDO_COLOR || xclass==GLX_STATIC_COLOR)
1217               && GET_VISUAL_DEPTH(v)>=4 && GET_VISUAL_DEPTH(v)<=16) {
1218	 if (!setup_dithered_color( client, v, b, cmap )) {
1219            return GL_FALSE;
1220         }
1221      }
1222      else {
1223	 _mesa_warning(NULL, "XMesa: RGB mode rendering not supported in given visual.");
1224	 return GL_FALSE;
1225      }
1226      v->mesa_visual.indexBits = 0;
1227
1228      if (_mesa_getenv("MESA_NO_DITHER")) {
1229	 v->dithered_pf = v->undithered_pf;
1230      }
1231   }
1232
1233
1234   /*
1235    * If MESA_INFO env var is set print out some debugging info
1236    * which can help Brian figure out what's going on when a user
1237    * reports bugs.
1238    */
1239   if (_mesa_getenv("MESA_INFO")) {
1240      _mesa_printf("X/Mesa visual = %p\n", (void *) v);
1241      _mesa_printf("X/Mesa dithered pf = %u\n", v->dithered_pf);
1242      _mesa_printf("X/Mesa undithered pf = %u\n", v->undithered_pf);
1243      _mesa_printf("X/Mesa level = %d\n", v->mesa_visual.level);
1244      _mesa_printf("X/Mesa depth = %d\n", GET_VISUAL_DEPTH(v));
1245      _mesa_printf("X/Mesa bits per pixel = %d\n", v->BitsPerPixel);
1246   }
1247
1248   if (b && window) {
1249      /* Do window-specific initializations */
1250
1251      /* Window dimensions */
1252      unsigned int w, h;
1253      get_drawable_size( v->display, window, &w, &h );
1254      b->width = w;
1255      b->height = h;
1256
1257      b->frontbuffer = window;
1258
1259      /* Setup for single/double buffering */
1260      if (v->mesa_visual.doubleBufferMode) {
1261         /* Double buffered */
1262#ifndef XFree86Server
1263         b->shm = check_for_xshm( v->display );
1264#endif
1265         xmesa_alloc_back_buffer( b );
1266         if (b->db_state==BACK_PIXMAP) {
1267            b->buffer = (XMesaDrawable)b->backpixmap;
1268         }
1269         else {
1270            b->buffer = XIMAGE;
1271         }
1272      }
1273      else {
1274         /* Single Buffered */
1275         b->buffer = b->frontbuffer;
1276      }
1277
1278      /* X11 graphics contexts */
1279#ifdef XFree86Server
1280      b->gc = CreateScratchGC(v->display, window->depth);
1281#else
1282      b->gc = XCreateGC( v->display, window, 0, NULL );
1283#endif
1284      XMesaSetFunction( v->display, b->gc, GXcopy );
1285
1286      /* cleargc - for glClear() */
1287#ifdef XFree86Server
1288      b->cleargc = CreateScratchGC(v->display, window->depth);
1289#else
1290      b->cleargc = XCreateGC( v->display, window, 0, NULL );
1291#endif
1292      XMesaSetFunction( v->display, b->cleargc, GXcopy );
1293
1294      /*
1295       * Don't generate Graphics Expose/NoExpose events in swapbuffers().
1296       * Patch contributed by Michael Pichler May 15, 1995.
1297       */
1298#ifdef XFree86Server
1299      b->swapgc = CreateScratchGC(v->display, window->depth);
1300      {
1301	  CARD32 v[1];
1302	  v[0] = FALSE;
1303	  dixChangeGC(NullClient, b->swapgc, GCGraphicsExposures, v, NULL);
1304      }
1305#else
1306      gcvalues.graphics_exposures = False;
1307      b->swapgc = XCreateGC( v->display, window,
1308                              GCGraphicsExposures, &gcvalues);
1309#endif
1310      XMesaSetFunction( v->display, b->swapgc, GXcopy );
1311      /*
1312       * Set fill style and tile pixmap once for all for HPCR stuff
1313       * (instead of doing it each time in clear_color_HPCR_pixmap())
1314       * Initialize whole stuff
1315       * Patch contributed by Jacques Leroy March 8, 1998.
1316       */
1317      if (v->hpcr_clear_flag && b->buffer!=XIMAGE) {
1318	int i;
1319	for (i=0; i<16; i++)
1320        {
1321	   XMesaPutPixel(v->hpcr_clear_ximage, i, 0, 0);
1322	   XMesaPutPixel(v->hpcr_clear_ximage, i, 1, 0);
1323        }
1324        XMesaPutImage(b->display, (XMesaDrawable)v->hpcr_clear_pixmap,
1325		      b->cleargc, v->hpcr_clear_ximage, 0, 0, 0, 0, 16, 2);
1326	XMesaSetFillStyle( v->display, b->cleargc, FillTiled);
1327	XMesaSetTile( v->display, b->cleargc, v->hpcr_clear_pixmap );
1328      }
1329
1330      /* Initialize the row buffer XImage for use in write_color_span() */
1331#ifdef XFree86Server
1332      b->rowimage = XMesaCreateImage(GET_VISUAL_DEPTH(v), MAX_WIDTH, 1,
1333				     (char *)MALLOC(MAX_WIDTH*4));
1334#else
1335      b->rowimage = XCreateImage( v->display,
1336                                  v->visinfo->visual,
1337                                  v->visinfo->depth,
1338                                  ZPixmap, 0,           /*format, offset*/
1339                                  (char*) MALLOC(MAX_WIDTH*4),  /*data*/
1340                                  MAX_WIDTH, 1,         /*width, height*/
1341                                  32,                   /*bitmap_pad*/
1342                                  0                     /*bytes_per_line*/ );
1343#endif
1344   }
1345
1346   return GL_TRUE;
1347}
1348
1349
1350
1351/*
1352 * Convert an RGBA color to a pixel value.
1353 */
1354unsigned long
1355xmesa_color_to_pixel( XMesaContext xmesa, GLubyte r, GLubyte g, GLubyte b, GLubyte a,
1356                      GLuint pixelFormat)
1357{
1358   switch (pixelFormat) {
1359      case PF_Index:
1360         return 0;
1361      case PF_Truecolor:
1362         {
1363            unsigned long p;
1364            PACK_TRUECOLOR( p, r, g, b );
1365            return p;
1366         }
1367      case PF_8A8B8G8R:
1368         return PACK_8A8B8G8R( r, g, b, a );
1369      case PF_8R8G8B:
1370         /* fall through */
1371      case PF_8R8G8B24:
1372         return PACK_8R8G8B( r, g, b );
1373      case PF_5R6G5B:
1374         return PACK_5R6G5B( r, g, b );
1375      case PF_Dither:
1376         {
1377            DITHER_SETUP;
1378            return DITHER( 1, 0, r, g, b );
1379         }
1380      case PF_1Bit:
1381         /* 382 = (3*255)/2 */
1382         return ((r+g+b) > 382) ^ xmesa->xm_visual->bitFlip;
1383      case PF_HPCR:
1384         return DITHER_HPCR(1, 1, r, g, b);
1385      case PF_Lookup:
1386         {
1387            LOOKUP_SETUP;
1388            return LOOKUP( r, g, b );
1389         }
1390      case PF_Grayscale:
1391         return GRAY_RGB( r, g, b );
1392      case PF_Dither_True:
1393         /* fall through */
1394      case PF_Dither_5R6G5B:
1395         {
1396            unsigned long p;
1397            PACK_TRUEDITHER(p, 1, 0, r, g, b);
1398            return p;
1399         }
1400      default:
1401         _mesa_problem(NULL, "Bad pixel format in xmesa_color_to_pixel");
1402   }
1403   return 0;
1404}
1405
1406
1407#define NUM_VISUAL_TYPES   6
1408
1409/**
1410 * Convert an X visual type to a GLX visual type.
1411 *
1412 * \param visualType X visual type (i.e., \c TrueColor, \c StaticGray, etc.)
1413 *        to be converted.
1414 * \return If \c visualType is a valid X visual type, a GLX visual type will
1415 *         be returned.  Otherwise \c GLX_NONE will be returned.
1416 *
1417 * \note
1418 * This code was lifted directly from lib/GL/glx/glcontextmodes.c in the
1419 * DRI CVS tree.
1420 */
1421static GLint
1422xmesa_convert_from_x_visual_type( int visualType )
1423{
1424    static const int glx_visual_types[ NUM_VISUAL_TYPES ] = {
1425	GLX_STATIC_GRAY,  GLX_GRAY_SCALE,
1426	GLX_STATIC_COLOR, GLX_PSEUDO_COLOR,
1427	GLX_TRUE_COLOR,   GLX_DIRECT_COLOR
1428    };
1429
1430    return ( (unsigned) visualType < NUM_VISUAL_TYPES )
1431	? glx_visual_types[ visualType ] : GLX_NONE;
1432}
1433
1434
1435/**********************************************************************/
1436/*****                       Public Functions                     *****/
1437/**********************************************************************/
1438
1439
1440/*
1441 * Create a new X/Mesa visual.
1442 * Input:  display - X11 display
1443 *         visinfo - an XVisualInfo pointer
1444 *         rgb_flag - GL_TRUE = RGB mode,
1445 *                    GL_FALSE = color index mode
1446 *         alpha_flag - alpha buffer requested?
1447 *         db_flag - GL_TRUE = double-buffered,
1448 *                   GL_FALSE = single buffered
1449 *         stereo_flag - stereo visual?
1450 *         ximage_flag - GL_TRUE = use an XImage for back buffer,
1451 *                       GL_FALSE = use an off-screen pixmap for back buffer
1452 *         depth_size - requested bits/depth values, or zero
1453 *         stencil_size - requested bits/stencil values, or zero
1454 *         accum_red_size - requested bits/red accum values, or zero
1455 *         accum_green_size - requested bits/green accum values, or zero
1456 *         accum_blue_size - requested bits/blue accum values, or zero
1457 *         accum_alpha_size - requested bits/alpha accum values, or zero
1458 *         num_samples - number of samples/pixel if multisampling, or zero
1459 *         level - visual level, usually 0
1460 *         visualCaveat - ala the GLX extension, usually GLX_NONE
1461 * Return;  a new XMesaVisual or 0 if error.
1462 */
1463XMesaVisual XMesaCreateVisual( XMesaDisplay *display,
1464                               XMesaVisualInfo visinfo,
1465                               GLboolean rgb_flag,
1466                               GLboolean alpha_flag,
1467                               GLboolean db_flag,
1468                               GLboolean stereo_flag,
1469                               GLboolean ximage_flag,
1470                               GLint depth_size,
1471                               GLint stencil_size,
1472                               GLint accum_red_size,
1473                               GLint accum_green_size,
1474                               GLint accum_blue_size,
1475                               GLint accum_alpha_size,
1476                               GLint num_samples,
1477                               GLint level,
1478                               GLint visualCaveat )
1479{
1480   char *gamma;
1481   XMesaVisual v;
1482   GLint red_bits, green_bits, blue_bits, alpha_bits;
1483
1484   /* For debugging only */
1485   if (_mesa_getenv("MESA_XSYNC")) {
1486      /* This makes debugging X easier.
1487       * In your debugger, set a breakpoint on _XError to stop when an
1488       * X protocol error is generated.
1489       */
1490#ifdef XFree86Server
1491      /* NOT_NEEDED */
1492#else
1493      XSynchronize( display, 1 );
1494#endif
1495   }
1496
1497   v = (XMesaVisual) CALLOC_STRUCT(xmesa_visual);
1498   if (!v) {
1499      return NULL;
1500   }
1501
1502   /*
1503    * In the X server, NULL is passed in for the display.  It will have
1504    * to be set before using this visual.  See XMesaSetVisualDisplay()
1505    * below.
1506    */
1507   v->display = display;
1508
1509   /* Save a copy of the XVisualInfo struct because the user may XFREE()
1510    * the struct but we may need some of the information contained in it
1511    * at a later time.
1512    */
1513#ifndef XFree86Server
1514   v->visinfo = (XVisualInfo *) MALLOC(sizeof(*visinfo));
1515   if(!v->visinfo) {
1516      FREE(v);
1517      return NULL;
1518   }
1519   MEMCPY(v->visinfo, visinfo, sizeof(*visinfo));
1520#endif
1521
1522   /* check for MESA_GAMMA environment variable */
1523   gamma = _mesa_getenv("MESA_GAMMA");
1524   if (gamma) {
1525      v->RedGamma = v->GreenGamma = v->BlueGamma = 0.0;
1526      sscanf( gamma, "%f %f %f", &v->RedGamma, &v->GreenGamma, &v->BlueGamma );
1527      if (v->RedGamma<=0.0)    v->RedGamma = 1.0;
1528      if (v->GreenGamma<=0.0)  v->GreenGamma = v->RedGamma;
1529      if (v->BlueGamma<=0.0)   v->BlueGamma = v->RedGamma;
1530   }
1531   else {
1532      v->RedGamma = v->GreenGamma = v->BlueGamma = 1.0;
1533   }
1534
1535   v->ximage_flag = ximage_flag;
1536
1537#ifdef XFree86Server
1538   /* We could calculate these values by ourselves.  nplanes is either the sum
1539    * of the red, green, and blue bits or the number index bits.
1540    * ColormapEntries is either (1U << index_bits) or
1541    * (1U << max(redBits, greenBits, blueBits)).
1542    */
1543   v->nplanes = visinfo->nplanes;
1544   v->ColormapEntries = visinfo->ColormapEntries;
1545
1546   v->mesa_visual.redMask = visinfo->redMask;
1547   v->mesa_visual.greenMask = visinfo->greenMask;
1548   v->mesa_visual.blueMask = visinfo->blueMask;
1549   v->mesa_visual.visualID = visinfo->vid;
1550   v->mesa_visual.screen = 0; /* FIXME: What should be done here? */
1551#else
1552   v->mesa_visual.redMask = visinfo->red_mask;
1553   v->mesa_visual.greenMask = visinfo->green_mask;
1554   v->mesa_visual.blueMask = visinfo->blue_mask;
1555   v->mesa_visual.visualID = visinfo->visualid;
1556   v->mesa_visual.screen = visinfo->screen;
1557#endif
1558
1559#if defined(XFree86Server) || !(defined(__cplusplus) || defined(c_plusplus))
1560   v->mesa_visual.visualType = xmesa_convert_from_x_visual_type(visinfo->class);
1561#else
1562   v->mesa_visual.visualType = xmesa_convert_from_x_visual_type(visinfo->c_class);
1563#endif
1564
1565   v->mesa_visual.visualRating = visualCaveat;
1566
1567   (void) initialize_visual_and_buffer( 0, v, NULL, rgb_flag, 0, 0 );
1568
1569   {
1570      const int xclass = v->mesa_visual.visualType;
1571      if (xclass==GLX_TRUE_COLOR || xclass==GLX_DIRECT_COLOR) {
1572         red_bits   = bitcount(GET_REDMASK(v));
1573         green_bits = bitcount(GET_GREENMASK(v));
1574         blue_bits  = bitcount(GET_BLUEMASK(v));
1575         alpha_bits = 0;
1576      }
1577      else {
1578         /* this is an approximation */
1579         int depth;
1580         depth = GET_VISUAL_DEPTH(v);
1581         red_bits = depth / 3;
1582         depth -= red_bits;
1583         green_bits = depth / 2;
1584         depth -= green_bits;
1585         blue_bits = depth;
1586         alpha_bits = 0;
1587         assert( red_bits + green_bits + blue_bits == GET_VISUAL_DEPTH(v) );
1588      }
1589   }
1590
1591   if (alpha_flag && alpha_bits == 0)
1592      alpha_bits = 8;
1593
1594   _mesa_initialize_visual( &v->mesa_visual,
1595                            rgb_flag, db_flag, stereo_flag,
1596                            red_bits, green_bits,
1597                            blue_bits, alpha_bits,
1598                            v->mesa_visual.indexBits,
1599                            depth_size,
1600                            stencil_size,
1601                            accum_red_size, accum_green_size,
1602                            accum_blue_size, accum_alpha_size,
1603                            0 );
1604
1605   /* XXX minor hack */
1606   v->mesa_visual.level = level;
1607   return v;
1608}
1609
1610
1611void XMesaSetVisualDisplay( XMesaDisplay *dpy, XMesaVisual v )
1612{
1613    v->display = dpy;
1614}
1615
1616
1617void XMesaDestroyVisual( XMesaVisual v )
1618{
1619#ifndef XFree86Server
1620   FREE(v->visinfo);
1621#endif
1622   FREE(v);
1623}
1624
1625
1626
1627/**
1628 * Create a new XMesaContext.
1629 * \param v  the XMesaVisual
1630 * \param share_list  another XMesaContext with which to share display
1631 *                    lists or NULL if no sharing is wanted.
1632 * \return an XMesaContext or NULL if error.
1633 */
1634XMesaContext XMesaCreateContext( XMesaVisual v, XMesaContext share_list )
1635{
1636   static GLboolean firstTime = GL_TRUE;
1637   XMesaContext c;
1638   GLcontext *mesaCtx;
1639   struct dd_function_table functions;
1640   TNLcontext *tnl;
1641
1642   if (firstTime) {
1643      _glthread_INIT_MUTEX(_xmesa_lock);
1644      firstTime = GL_FALSE;
1645   }
1646
1647   /* Note: the XMesaContext contains a Mesa GLcontext struct (inheritance) */
1648   c = (XMesaContext) CALLOC_STRUCT(xmesa_context);
1649   if (!c)
1650      return NULL;
1651
1652   mesaCtx = &(c->mesa);
1653
1654   /* initialize with default driver functions, then plug in XMesa funcs */
1655   _mesa_init_driver_functions(&functions);
1656   xmesa_init_driver_functions(v, &functions);
1657   if (!_mesa_initialize_context(mesaCtx, &v->mesa_visual,
1658                      share_list ? &(share_list->mesa) : (GLcontext *) NULL,
1659                      &functions, (void *) c)) {
1660      FREE(c);
1661      return NULL;
1662   }
1663
1664   _mesa_enable_sw_extensions(mesaCtx);
1665   _mesa_enable_1_3_extensions(mesaCtx);
1666   _mesa_enable_1_4_extensions(mesaCtx);
1667   _mesa_enable_1_5_extensions(mesaCtx);
1668
1669   /* finish up xmesa context initializations */
1670   c->swapbytes = CHECK_BYTE_ORDER(v) ? GL_FALSE : GL_TRUE;
1671   c->xm_visual = v;
1672   c->xm_draw_buffer = NULL;   /* set later by XMesaMakeCurrent */
1673   c->xm_read_buffer = NULL;   /* set later by XMesaMakeCurrent */
1674   c->xm_buffer = NULL;   /* set later by XMesaMakeCurrent */
1675   c->display = v->display;
1676   c->pixelformat = v->dithered_pf;      /* Dithering is enabled by default */
1677
1678   /* Initialize the software rasterizer and helper modules.
1679    */
1680   if (!_swrast_CreateContext( mesaCtx ) ||
1681       !_ac_CreateContext( mesaCtx ) ||
1682       !_tnl_CreateContext( mesaCtx ) ||
1683       !_swsetup_CreateContext( mesaCtx )) {
1684      _mesa_free_context_data(&c->mesa);
1685      _mesa_free(c);
1686      return NULL;
1687   }
1688
1689   /* tnl setup */
1690   tnl = TNL_CONTEXT(mesaCtx);
1691   tnl->Driver.RunPipeline = _tnl_run_pipeline;
1692   /* swrast setup */
1693   xmesa_register_swrast_functions( mesaCtx );
1694   _swsetup_Wakeup(mesaCtx);
1695
1696   return c;
1697}
1698
1699
1700
1701void XMesaDestroyContext( XMesaContext c )
1702{
1703   GLcontext *mesaCtx = &c->mesa;
1704#ifdef FX
1705   if (c->xm_draw_buffer && c->xm_buffer->FXctx)
1706      fxMesaDestroyContext(c->xm_draw_buffer->FXctx);
1707#endif
1708   _swsetup_DestroyContext( mesaCtx );
1709   _swrast_DestroyContext( mesaCtx );
1710   _tnl_DestroyContext( mesaCtx );
1711   _ac_DestroyContext( mesaCtx );
1712   _mesa_free_context_data( mesaCtx );
1713   _mesa_free( c );
1714}
1715
1716
1717
1718/*
1719 * XXX this isn't a public function!  It's a hack for the 3Dfx driver.
1720 * Create a new XMesaBuffer from an X window.
1721 * Input:  v - the XMesaVisual
1722 *         w - the window
1723 *         c - the context
1724 * Return:  new XMesaBuffer or NULL if error
1725 */
1726XMesaBuffer XMesaCreateWindowBuffer2( XMesaVisual v, XMesaWindow w,
1727                                      XMesaContext c )
1728{
1729#ifndef XFree86Server
1730   XWindowAttributes attr;
1731#endif
1732#ifdef FX
1733   char *fxEnvVar;
1734#endif
1735   int client = 0;
1736
1737   XMesaBuffer b = alloc_xmesa_buffer();
1738   if (!b) {
1739      return NULL;
1740   }
1741
1742   (void) c;
1743
1744#ifdef XFree86Server
1745   client = CLIENT_ID(((XMesaDrawable)w)->id);
1746#endif
1747
1748   assert(v);
1749
1750#ifdef XFree86Server
1751   if (GET_VISUAL_DEPTH(v) != ((XMesaDrawable)w)->depth) {
1752#else
1753   XGetWindowAttributes( v->display, w, &attr );
1754
1755   if (GET_VISUAL_DEPTH(v) != attr.depth) {
1756#endif
1757      _mesa_warning(NULL, "XMesaCreateWindowBuffer: depth mismatch between visual and window!\n");
1758      return NULL;
1759   }
1760
1761   b->xm_visual = v;
1762   b->type = WINDOW;
1763   b->display = v->display;
1764#ifdef XFree86Server
1765   b->cmap = (ColormapPtr)LookupIDByType(wColormap(w), RT_COLORMAP);
1766#else
1767   if (attr.colormap) {
1768      b->cmap = attr.colormap;
1769   }
1770   else {
1771      _mesa_warning(NULL, "Window %u has no colormap!\n", (unsigned int) w);
1772      /* this is weird, a window w/out a colormap!? */
1773      /* OK, let's just allocate a new one and hope for the best */
1774      b->cmap = XCreateColormap(v->display, w, attr.visual, AllocNone);
1775   }
1776#endif
1777
1778   /* determine back buffer implementation */
1779   if (v->mesa_visual.doubleBufferMode) {
1780      if (v->ximage_flag) {
1781	 b->db_state = BACK_XIMAGE;
1782      }
1783      else {
1784	 b->db_state = BACK_PIXMAP;
1785      }
1786   }
1787   else {
1788      b->db_state = 0;
1789   }
1790
1791   _mesa_initialize_framebuffer(&b->mesa_buffer,
1792                                &v->mesa_visual,
1793                                v->mesa_visual.depthBits > 0,
1794                                v->mesa_visual.stencilBits > 0,
1795                                v->mesa_visual.accumRedBits > 0,
1796                                v->mesa_visual.alphaBits > 0 );
1797   /* XXX hack */
1798   b->mesa_buffer.UseSoftwareAuxBuffers = GL_TRUE;
1799
1800   if (!initialize_visual_and_buffer( client, v, b, v->mesa_visual.rgbMode,
1801                                      (XMesaDrawable)w, b->cmap )) {
1802      free_xmesa_buffer(client, b);
1803      return NULL;
1804   }
1805
1806#ifdef FX
1807   fxEnvVar = _mesa_getenv("MESA_GLX_FX");
1808   if (fxEnvVar) {
1809     if (fxEnvVar[0]!='d') {
1810       int attribs[100];
1811       int numAttribs = 0;
1812       int hw;
1813       if (v->mesa_visual.depthBits > 0) {
1814	 attribs[numAttribs++] = FXMESA_DEPTH_SIZE;
1815	 attribs[numAttribs++] = v->mesa_visual.depthBits;
1816       }
1817       if (v->mesa_visual.doubleBufferMode) {
1818	 attribs[numAttribs++] = FXMESA_DOUBLEBUFFER;
1819       }
1820       if (v->mesa_visual.accumRedBits > 0) {
1821	 attribs[numAttribs++] = FXMESA_ACCUM_SIZE;
1822	 attribs[numAttribs++] = v->mesa_visual.accumRedBits;
1823       }
1824       if (v->mesa_visual.stencilBits > 0) {
1825         attribs[numAttribs++] = FXMESA_STENCIL_SIZE;
1826         attribs[numAttribs++] = v->mesa_visual.stencilBits;
1827       }
1828       if (v->mesa_visual.alphaBits > 0) {
1829         attribs[numAttribs++] = FXMESA_ALPHA_SIZE;
1830         attribs[numAttribs++] = v->mesa_visual.alphaBits;
1831       }
1832       if (1) {
1833         attribs[numAttribs++] = FXMESA_SHARE_CONTEXT;
1834         attribs[numAttribs++] = (int) &(c->mesa);
1835       }
1836       attribs[numAttribs++] = FXMESA_NONE;
1837
1838       /* [dBorca] we should take an envvar for `fxMesaSelectCurrentBoard'!!! */
1839       hw = fxMesaSelectCurrentBoard(0);
1840       if ((hw == GR_SSTTYPE_VOODOO) || (hw == GR_SSTTYPE_Voodoo2)) {
1841         b->FXctx = fxMesaCreateBestContext(0, b->width, b->height, attribs);
1842         if ((v->undithered_pf!=PF_Index) && (b->backimage)) {
1843	   b->FXisHackUsable = b->FXctx ? GL_TRUE : GL_FALSE;
1844	   if (b->FXctx && (fxEnvVar[0]=='w' || fxEnvVar[0]=='W')) {
1845	     b->FXwindowHack = GL_TRUE;
1846	     FX_grSstControl(GR_CONTROL_DEACTIVATE);
1847	   }
1848           else {
1849	     b->FXwindowHack = GL_FALSE;
1850	   }
1851         }
1852       }
1853       else {
1854         if (fxEnvVar[0]=='w' || fxEnvVar[0]=='W')
1855	   b->FXctx = fxMesaCreateContext(w, GR_RESOLUTION_NONE,
1856					  GR_REFRESH_75Hz, attribs);
1857         else
1858	   b->FXctx = fxMesaCreateBestContext(0, b->width, b->height, attribs);
1859         b->FXisHackUsable = GL_FALSE;
1860         b->FXwindowHack = GL_FALSE;
1861       }
1862       /*
1863       fprintf(stderr,
1864               "voodoo %d, wid %d height %d hack: usable %d active %d\n",
1865               hw, b->width, b->height, b->FXisHackUsable, b->FXwindowHack);
1866       */
1867     }
1868   }
1869   else {
1870      _mesa_warning(NULL, "WARNING: This Mesa Library includes the Glide driver but\n");
1871      _mesa_warning(NULL, "         you have not defined the MESA_GLX_FX env. var.\n");
1872      _mesa_warning(NULL, "         (check the README.3DFX file for more information).\n\n");
1873      _mesa_warning(NULL, "         you can disable this message with a 'export MESA_GLX_FX=disable'.\n");
1874   }
1875#endif
1876
1877   return b;
1878}
1879
1880
1881XMesaBuffer XMesaCreateWindowBuffer( XMesaVisual v, XMesaWindow w )
1882{
1883   return XMesaCreateWindowBuffer2( v, w, NULL );
1884}
1885
1886
1887/**
1888 * Create a new XMesaBuffer from an X pixmap.
1889 *
1890 * \param v    the XMesaVisual
1891 * \param p    the pixmap
1892 * \param cmap the colormap, may be 0 if using a \c GLX_TRUE_COLOR or
1893 *             \c GLX_DIRECT_COLOR visual for the pixmap
1894 * \returns new XMesaBuffer or NULL if error
1895 */
1896XMesaBuffer XMesaCreatePixmapBuffer( XMesaVisual v,
1897				     XMesaPixmap p, XMesaColormap cmap )
1898{
1899   int client = 0;
1900   XMesaBuffer b = alloc_xmesa_buffer();
1901   if (!b) {
1902      return NULL;
1903   }
1904
1905
1906#ifdef XFree86Server
1907   client = CLIENT_ID(((XMesaDrawable)p)->id);
1908#endif
1909
1910   assert(v);
1911
1912   b->xm_visual = v;
1913   b->type = PIXMAP;
1914   b->display = v->display;
1915   b->cmap = cmap;
1916
1917   /* determine back buffer implementation */
1918   if (v->mesa_visual.doubleBufferMode) {
1919      if (v->ximage_flag) {
1920	 b->db_state = BACK_XIMAGE;
1921      }
1922      else {
1923	 b->db_state = BACK_PIXMAP;
1924      }
1925   }
1926   else {
1927      b->db_state = 0;
1928   }
1929
1930   _mesa_initialize_framebuffer(&b->mesa_buffer,
1931                                &v->mesa_visual,
1932                                v->mesa_visual.depthBits > 0,
1933                                v->mesa_visual.stencilBits > 0,
1934                                v->mesa_visual.accumRedBits +
1935                                v->mesa_visual.accumGreenBits +
1936                                v->mesa_visual.accumBlueBits > 0,
1937                                v->mesa_visual.alphaBits > 0 );
1938
1939   if (!initialize_visual_and_buffer(client, v, b, v->mesa_visual.rgbMode,
1940				     (XMesaDrawable)p, cmap)) {
1941      free_xmesa_buffer(client, b);
1942      return NULL;
1943   }
1944
1945   return b;
1946}
1947
1948
1949
1950XMesaBuffer XMesaCreatePBuffer( XMesaVisual v, XMesaColormap cmap,
1951                                unsigned int width, unsigned int height )
1952{
1953#ifdef XFree86Server
1954   return 0;
1955#else
1956   int client = 0;
1957   XMesaWindow root;
1958   XMesaDrawable drawable;  /* X Pixmap Drawable */
1959   XMesaBuffer b = alloc_xmesa_buffer();
1960   if (!b) {
1961      return NULL;
1962   }
1963
1964   b->xm_visual = v;
1965   b->type = PBUFFER;
1966   b->display = v->display;
1967   b->cmap = cmap;
1968
1969   /* allocate pixmap for front buffer */
1970   root = RootWindow( v->display, v->visinfo->screen );
1971   drawable = XCreatePixmap( v->display, root, width, height, v->visinfo->depth );
1972
1973   /* determine back buffer implementation */
1974   if (v->mesa_visual.doubleBufferMode) {
1975      if (v->ximage_flag) {
1976	 b->db_state = BACK_XIMAGE;
1977      }
1978      else {
1979	 b->db_state = BACK_PIXMAP;
1980      }
1981   }
1982   else {
1983      b->db_state = 0;
1984   }
1985
1986   _mesa_initialize_framebuffer(&b->mesa_buffer,
1987                                &v->mesa_visual,
1988                                v->mesa_visual.depthBits > 0,
1989                                v->mesa_visual.stencilBits > 0,
1990                                v->mesa_visual.accumRedBits +
1991                                v->mesa_visual.accumGreenBits +
1992                                v->mesa_visual.accumBlueBits > 0,
1993                                v->mesa_visual.alphaBits > 0 );
1994
1995   if (!initialize_visual_and_buffer(client, v, b, v->mesa_visual.rgbMode,
1996				     drawable, cmap)) {
1997      free_xmesa_buffer(client, b);
1998      return NULL;
1999   }
2000
2001   return b;
2002#endif
2003}
2004
2005
2006
2007/*
2008 * Deallocate an XMesaBuffer structure and all related info.
2009 */
2010void XMesaDestroyBuffer( XMesaBuffer b )
2011{
2012   int client = 0;
2013
2014#ifdef XFree86Server
2015   if (b->frontbuffer)
2016       client = CLIENT_ID(b->frontbuffer->id);
2017#endif
2018
2019   if (b->gc)  XMesaFreeGC( b->xm_visual->display, b->gc );
2020   if (b->cleargc)  XMesaFreeGC( b->xm_visual->display, b->cleargc );
2021   if (b->swapgc)  XMesaFreeGC( b->xm_visual->display, b->swapgc );
2022
2023   if (b->backimage) {
2024#if defined(USE_XSHM) && !defined(XFree86Server)
2025       if (b->shm) {
2026	   XShmDetach( b->xm_visual->display, &b->shminfo );
2027	   XDestroyImage( b->backimage );
2028	   shmdt( b->shminfo.shmaddr );
2029       }
2030       else
2031#endif
2032	   XMesaDestroyImage( b->backimage );
2033   }
2034   if (b->backpixmap) {
2035      XMesaFreePixmap( b->xm_visual->display, b->backpixmap );
2036      if (b->xm_visual->hpcr_clear_flag) {
2037	XMesaFreePixmap( b->xm_visual->display,
2038			 b->xm_visual->hpcr_clear_pixmap );
2039	XMesaDestroyImage( b->xm_visual->hpcr_clear_ximage );
2040      }
2041   }
2042   if (b->rowimage) {
2043      FREE( b->rowimage->data );
2044      b->rowimage->data = NULL;
2045      XMesaDestroyImage( b->rowimage );
2046   }
2047
2048   free_xmesa_buffer(client, b);
2049}
2050
2051
2052
2053/*
2054 * Bind buffer b to context c and make c the current rendering context.
2055 */
2056GLboolean XMesaMakeCurrent( XMesaContext c, XMesaBuffer b )
2057{
2058   return XMesaMakeCurrent2( c, b, b );
2059}
2060
2061
2062/*
2063 * Bind buffer b to context c and make c the current rendering context.
2064 */
2065GLboolean XMesaMakeCurrent2( XMesaContext c, XMesaBuffer drawBuffer,
2066                             XMesaBuffer readBuffer )
2067{
2068   if (c) {
2069      if (!drawBuffer || !readBuffer)
2070         return GL_FALSE;  /* must specify buffers! */
2071
2072#ifdef FX
2073      if (drawBuffer->FXctx) {
2074         fxMesaMakeCurrent(drawBuffer->FXctx);
2075
2076         c->xm_draw_buffer = drawBuffer;
2077         c->xm_read_buffer = readBuffer;
2078         c->xm_buffer = drawBuffer;
2079
2080         return GL_TRUE;
2081      }
2082#endif
2083      if (&(c->mesa) == _mesa_get_current_context()
2084          && c->xm_draw_buffer == drawBuffer
2085          && c->xm_read_buffer == readBuffer
2086          && c->xm_draw_buffer->wasCurrent) {
2087         /* same context and buffer, do nothing */
2088         return GL_TRUE;
2089      }
2090
2091      c->xm_draw_buffer = drawBuffer;
2092      c->xm_read_buffer = readBuffer;
2093      c->xm_buffer = drawBuffer;
2094
2095      _mesa_make_current2(&(c->mesa),
2096                          &drawBuffer->mesa_buffer,
2097                          &readBuffer->mesa_buffer);
2098
2099      if (c->mesa.Viewport.Width == 0) {
2100	 /* initialize viewport to window size */
2101	 _mesa_Viewport( 0, 0, drawBuffer->width, drawBuffer->height );
2102	 c->mesa.Scissor.Width = drawBuffer->width;
2103	 c->mesa.Scissor.Height = drawBuffer->height;
2104      }
2105
2106      if (c->xm_visual->mesa_visual.rgbMode) {
2107         /*
2108          * Must recompute and set these pixel values because colormap
2109          * can be different for different windows.
2110          */
2111         c->clearpixel = xmesa_color_to_pixel( c,
2112                                               c->clearcolor[0],
2113                                               c->clearcolor[1],
2114                                               c->clearcolor[2],
2115                                               c->clearcolor[3],
2116                                               c->xm_visual->undithered_pf);
2117         XMesaSetForeground(c->display, c->xm_draw_buffer->cleargc, c->clearpixel);
2118      }
2119
2120      /* Solution to Stephane Rehel's problem with glXReleaseBuffersMESA(): */
2121      c->xm_draw_buffer->wasCurrent = GL_TRUE;
2122   }
2123   else {
2124      /* Detach */
2125      _mesa_make_current2( NULL, NULL, NULL );
2126   }
2127   return GL_TRUE;
2128}
2129
2130
2131/*
2132 * Unbind the context c from its buffer.
2133 */
2134GLboolean XMesaUnbindContext( XMesaContext c )
2135{
2136   /* A no-op for XFree86 integration purposes */
2137   return GL_TRUE;
2138}
2139
2140
2141XMesaContext XMesaGetCurrentContext( void )
2142{
2143   GET_CURRENT_CONTEXT(ctx);
2144   if (ctx) {
2145      XMesaContext xmesa = XMESA_CONTEXT(ctx);
2146      return xmesa;
2147   }
2148   else {
2149      return 0;
2150   }
2151}
2152
2153
2154XMesaBuffer XMesaGetCurrentBuffer( void )
2155{
2156   GET_CURRENT_CONTEXT(ctx);
2157   if (ctx) {
2158      XMesaContext xmesa = XMESA_CONTEXT(ctx);
2159      return xmesa->xm_draw_buffer;
2160   }
2161   else {
2162      return 0;
2163   }
2164}
2165
2166
2167/* New in Mesa 3.1 */
2168XMesaBuffer XMesaGetCurrentReadBuffer( void )
2169{
2170   GET_CURRENT_CONTEXT(ctx);
2171   if (ctx) {
2172      XMesaContext xmesa = XMESA_CONTEXT(ctx);
2173      return xmesa->xm_read_buffer;
2174   }
2175   else {
2176      return 0;
2177   }
2178}
2179
2180
2181GLboolean XMesaForceCurrent(XMesaContext c)
2182{
2183   if (c) {
2184      if (&(c->mesa) != _mesa_get_current_context()) {
2185	 _mesa_make_current(&(c->mesa), &c->xm_draw_buffer->mesa_buffer);
2186      }
2187   }
2188   else {
2189      _mesa_make_current(NULL, NULL);
2190   }
2191   return GL_TRUE;
2192}
2193
2194
2195GLboolean XMesaLoseCurrent(XMesaContext c)
2196{
2197   (void) c;
2198   _mesa_make_current(NULL, NULL);
2199   return GL_TRUE;
2200}
2201
2202
2203/*
2204 * Switch 3Dfx support hack between window and full-screen mode.
2205 */
2206GLboolean XMesaSetFXmode( GLint mode )
2207{
2208#ifdef FX
2209   const char *fx = _mesa_getenv("MESA_GLX_FX");
2210   if (fx && fx[0] != 'd') {
2211      GET_CURRENT_CONTEXT(ctx);
2212      GrHwConfiguration hw;
2213      if (!FX_grSstQueryHardware(&hw)) {
2214         /*fprintf(stderr, "!grSstQueryHardware\n");*/
2215         return GL_FALSE;
2216      }
2217      if (hw.num_sst < 1) {
2218         /*fprintf(stderr, "hw.num_sst < 1\n");*/
2219         return GL_FALSE;
2220      }
2221      if (ctx) {
2222         /* [dBorca] Hack alert:
2223	  * oh, this is sooo wrong: ctx above is
2224	  * really an fxMesaContext, not an XMesaContext
2225	  */
2226         XMesaContext xmesa = XMESA_CONTEXT(ctx);
2227         if (mode == XMESA_FX_WINDOW) {
2228	    if (xmesa->xm_draw_buffer->FXisHackUsable) {
2229	       FX_grSstControl(GR_CONTROL_DEACTIVATE);
2230	       xmesa->xm_draw_buffer->FXwindowHack = GL_TRUE;
2231	       return GL_TRUE;
2232	    }
2233	 }
2234	 else if (mode == XMESA_FX_FULLSCREEN) {
2235	    FX_grSstControl(GR_CONTROL_ACTIVATE);
2236	    xmesa->xm_draw_buffer->FXwindowHack = GL_FALSE;
2237	    return GL_TRUE;
2238	 }
2239	 else {
2240	    /* Error: Bad mode value */
2241	 }
2242      }
2243   }
2244   /*fprintf(stderr, "fallthrough\n");*/
2245#else
2246   (void) mode;
2247#endif
2248   return GL_FALSE;
2249}
2250
2251
2252
2253#ifdef FX
2254/*
2255 * Read image from VooDoo frame buffer into X/Mesa's back XImage.
2256 */
2257static void FXgetImage( XMesaBuffer b )
2258{
2259   GET_CURRENT_CONTEXT(ctx);
2260   static unsigned short pixbuf[MAX_WIDTH];
2261   GLuint x, y;
2262   int xpos, ypos;
2263   XMesaWindow root;
2264   unsigned int bw, depth, width, height;
2265   XMesaContext xmesa = XMESA_CONTEXT(ctx);
2266
2267#ifdef XFree86Server
2268   x = b->frontbuffer->x;
2269   y = b->frontbuffer->y;
2270   width = b->frontbuffer->width;
2271   height = b->frontbuffer->height;
2272   depth = b->frontbuffer->depth;
2273#else
2274   XGetGeometry( b->xm_visual->display, b->frontbuffer,
2275                 &root, &xpos, &ypos, &width, &height, &bw, &depth);
2276#endif
2277   if (b->width != width || b->height != height) {
2278      b->width = MIN2((int)width, b->FXctx->width);
2279      b->height = MIN2((int)height, b->FXctx->height);
2280      if (b->width & 1)
2281         b->width--;  /* prevent odd width */
2282      xmesa_alloc_back_buffer( b );
2283   }
2284
2285   /* [dBorca] we're always in the right GR_COLORFORMAT... aren't we? */
2286   /* grLfbWriteColorFormat(GR_COLORFORMAT_ARGB); */
2287   if (b->xm_visual->undithered_pf==PF_5R6G5B) {
2288      /* Special case: 16bpp RGB */
2289      grLfbReadRegion( GR_BUFFER_FRONTBUFFER,       /* src buffer */
2290                       0, b->FXctx->height - b->height,  /*pos*/
2291                       b->width, b->height,         /* size */
2292                       b->width * sizeof(GLushort), /* stride */
2293                       b->backimage->data);         /* dest buffer */
2294   }
2295   else if (b->xm_visual->dithered_pf==PF_Dither
2296	    && GET_VISUAL_DEPTH(b->xm_visual)==8) {
2297      /* Special case: 8bpp RGB */
2298      for (y=0;y<b->height;y++) {
2299         GLubyte *ptr = (GLubyte*) b->backimage->data
2300                        + b->backimage->bytes_per_line * y;
2301         XDITHER_SETUP(y);
2302
2303         /* read row from 3Dfx frame buffer */
2304         grLfbReadRegion( GR_BUFFER_FRONTBUFFER,
2305                          0, b->FXctx->height-(b->height-y),
2306                          b->width, 1,
2307                          0,
2308                          pixbuf );
2309
2310         /* write to XImage back buffer */
2311         for (x=0;x<b->width;x++) {
2312            GLubyte r = (pixbuf[x] & 0xf800) >> 8;
2313            GLubyte g = (pixbuf[x] & 0x07e0) >> 3;
2314            GLubyte b = (pixbuf[x] & 0x001f) << 3;
2315            *ptr++ = XDITHER( x, r, g, b);
2316         }
2317      }
2318   }
2319   else {
2320      /* General case: slow! */
2321      for (y=0;y<b->height;y++) {
2322         /* read row from 3Dfx frame buffer */
2323         grLfbReadRegion( GR_BUFFER_FRONTBUFFER,
2324                          0, b->FXctx->height-(b->height-y),
2325                          b->width, 1,
2326                          0,
2327                          pixbuf );
2328
2329         /* write to XImage back buffer */
2330         for (x=0;x<b->width;x++) {
2331            XMesaPutPixel(b->backimage,x,y,
2332			  xmesa_color_to_pixel(xmesa,
2333					       (pixbuf[x] & 0xf800) >> 8,
2334					       (pixbuf[x] & 0x07e0) >> 3,
2335					       (pixbuf[x] & 0x001f) << 3,
2336					       0xff,
2337                                               b->xm_visual->undithered_pf));
2338         }
2339      }
2340   }
2341   /* grLfbWriteColorFormat(GR_COLORFORMAT_ABGR); */
2342}
2343#endif
2344
2345
2346/*
2347 * Copy the back buffer to the front buffer.  If there's no back buffer
2348 * this is a no-op.
2349 */
2350void XMesaSwapBuffers( XMesaBuffer b )
2351{
2352   GET_CURRENT_CONTEXT(ctx);
2353
2354   /* If we're swapping the buffer associated with the current context
2355    * we have to flush any pending rendering commands first.
2356    */
2357   if (ctx && ctx->DrawBuffer == &(b->mesa_buffer))
2358      _mesa_notifySwapBuffers(ctx);
2359
2360   if (b->db_state) {
2361#ifdef FX
2362      if (b->FXctx) {
2363         fxMesaSwapBuffers();
2364
2365         if (b->FXwindowHack)
2366            FXgetImage(b);
2367         else
2368            return;
2369      }
2370#endif
2371     if (b->backimage) {
2372	 /* Copy Ximage from host's memory to server's window */
2373#if defined(USE_XSHM) && !defined(XFree86Server)
2374	 if (b->shm) {
2375            /*_glthread_LOCK_MUTEX(_xmesa_lock);*/
2376	    XShmPutImage( b->xm_visual->display, b->frontbuffer,
2377			  b->swapgc,
2378			  b->backimage, 0, 0,
2379			  0, 0, b->width, b->height, False );
2380            /*_glthread_UNLOCK_MUTEX(_xmesa_lock);*/
2381	 }
2382	 else
2383#endif
2384         {
2385            /*_glthread_LOCK_MUTEX(_xmesa_lock);*/
2386            XMesaPutImage( b->xm_visual->display, b->frontbuffer,
2387			   b->swapgc,
2388			   b->backimage, 0, 0,
2389			   0, 0, b->width, b->height );
2390            /*_glthread_UNLOCK_MUTEX(_xmesa_lock);*/
2391         }
2392      }
2393      else {
2394	 /* Copy pixmap to window on server */
2395         /*_glthread_LOCK_MUTEX(_xmesa_lock);*/
2396	 XMesaCopyArea( b->xm_visual->display,
2397			b->backpixmap,   /* source drawable */
2398			b->frontbuffer,  /* dest. drawable */
2399			b->swapgc,
2400			0, 0, b->width, b->height,  /* source region */
2401			0, 0                 /* dest region */
2402		      );
2403         /*_glthread_UNLOCK_MUTEX(_xmesa_lock);*/
2404      }
2405   }
2406#if !defined(XFree86Server)
2407   XSync( b->xm_visual->display, False );
2408#endif
2409}
2410
2411
2412
2413/*
2414 * Copy sub-region of back buffer to front buffer
2415 */
2416void XMesaCopySubBuffer( XMesaBuffer b, int x, int y, int width, int height )
2417{
2418   GET_CURRENT_CONTEXT(ctx);
2419
2420   /* If we're swapping the buffer associated with the current context
2421    * we have to flush any pending rendering commands first.
2422    */
2423   if (ctx && ctx->DrawBuffer == &(b->mesa_buffer))
2424      _mesa_notifySwapBuffers(ctx);
2425
2426   if (b->db_state) {
2427      int yTop = b->height - y - height;
2428#ifdef FX
2429      if (b->FXctx) {
2430         fxMesaSwapBuffers();
2431         if (b->FXwindowHack)
2432            FXgetImage(b);
2433         else
2434            return;
2435      }
2436#endif
2437      if (b->backimage) {
2438         /* Copy Ximage from host's memory to server's window */
2439#if defined(USE_XSHM) && !defined(XFree86Server)
2440         if (b->shm) {
2441            /* XXX assuming width and height aren't too large! */
2442            XShmPutImage( b->xm_visual->display, b->frontbuffer,
2443                          b->swapgc,
2444                          b->backimage, x, yTop,
2445                          x, yTop, width, height, False );
2446            /* wait for finished event??? */
2447         }
2448         else
2449#endif
2450         {
2451            /* XXX assuming width and height aren't too large! */
2452            XMesaPutImage( b->xm_visual->display, b->frontbuffer,
2453			   b->swapgc,
2454			   b->backimage, x, yTop,
2455			   x, yTop, width, height );
2456         }
2457      }
2458      else {
2459         /* Copy pixmap to window on server */
2460         XMesaCopyArea( b->xm_visual->display,
2461			b->backpixmap,           /* source drawable */
2462			b->frontbuffer,          /* dest. drawable */
2463			b->swapgc,
2464			x, yTop, width, height,  /* source region */
2465			x, yTop                  /* dest region */
2466                      );
2467      }
2468   }
2469}
2470
2471
2472/*
2473 * Return a pointer to the XMesa backbuffer Pixmap or XImage.  This function
2474 * is a way to get "under the hood" of X/Mesa so one can manipulate the
2475 * back buffer directly.
2476 * Output:  pixmap - pointer to back buffer's Pixmap, or 0
2477 *          ximage - pointer to back buffer's XImage, or NULL
2478 * Return:  GL_TRUE = context is double buffered
2479 *          GL_FALSE = context is single buffered
2480 */
2481GLboolean XMesaGetBackBuffer( XMesaBuffer b,
2482                              XMesaPixmap *pixmap,
2483                              XMesaImage **ximage )
2484{
2485   if (b->db_state) {
2486      if (pixmap)  *pixmap = b->backpixmap;
2487      if (ximage)  *ximage = b->backimage;
2488      return GL_TRUE;
2489   }
2490   else {
2491      *pixmap = 0;
2492      *ximage = NULL;
2493      return GL_FALSE;
2494   }
2495}
2496
2497
2498/*
2499 * Return the depth buffer associated with an XMesaBuffer.
2500 * Input:  b - the XMesa buffer handle
2501 * Output:  width, height - size of buffer in pixels
2502 *          bytesPerValue - bytes per depth value (2 or 4)
2503 *          buffer - pointer to depth buffer values
2504 * Return:  GL_TRUE or GL_FALSE to indicate success or failure.
2505 */
2506GLboolean XMesaGetDepthBuffer( XMesaBuffer b, GLint *width, GLint *height,
2507                               GLint *bytesPerValue, void **buffer )
2508{
2509   if (!b->mesa_buffer.DepthBuffer) {
2510      *width = 0;
2511      *height = 0;
2512      *bytesPerValue = 0;
2513      *buffer = 0;
2514      return GL_FALSE;
2515   }
2516   else {
2517      *width = b->mesa_buffer.Width;
2518      *height = b->mesa_buffer.Height;
2519      *bytesPerValue = sizeof(GLdepth);
2520      *buffer = b->mesa_buffer.DepthBuffer;
2521      return GL_TRUE;
2522   }
2523}
2524
2525
2526void XMesaFlush( XMesaContext c )
2527{
2528   if (c && c->xm_visual) {
2529#ifdef XFree86Server
2530      /* NOT_NEEDED */
2531#else
2532      XSync( c->xm_visual->display, False );
2533#endif
2534   }
2535}
2536
2537
2538
2539const char *XMesaGetString( XMesaContext c, int name )
2540{
2541   (void) c;
2542   if (name==XMESA_VERSION) {
2543      return "5.0";
2544   }
2545   else if (name==XMESA_EXTENSIONS) {
2546      return "";
2547   }
2548   else {
2549      return NULL;
2550   }
2551}
2552
2553
2554
2555XMesaBuffer XMesaFindBuffer( XMesaDisplay *dpy, XMesaDrawable d )
2556{
2557   XMesaBuffer b;
2558   for (b=XMesaBufferList; b; b=b->Next) {
2559      if (b->frontbuffer==d && b->display==dpy) {
2560         return b;
2561      }
2562   }
2563   return NULL;
2564}
2565
2566
2567
2568/*
2569 * Look for XMesaBuffers whose X window has been destroyed.
2570 * Deallocate any such XMesaBuffers.
2571 */
2572void XMesaGarbageCollect( void )
2573{
2574   XMesaBuffer b, next;
2575   for (b=XMesaBufferList; b; b=next) {
2576      next = b->Next;
2577      if (b->display && b->frontbuffer && b->type == WINDOW) {
2578#ifdef XFree86Server
2579	 /* NOT_NEEDED */
2580#else
2581         XSync(b->display, False);
2582         if (!window_exists( b->display, b->frontbuffer )) {
2583            /* found a dead window, free the ancillary info */
2584            XMesaDestroyBuffer( b );
2585         }
2586#endif
2587      }
2588   }
2589}
2590
2591
2592void XMesaReset( void )
2593{
2594    while (XMesaBufferList)
2595	XMesaDestroyBuffer(XMesaBufferList);
2596
2597    XMesaBufferList = NULL;
2598}
2599
2600
2601unsigned long XMesaDitherColor( XMesaContext xmesa, GLint x, GLint y,
2602                                GLfloat red, GLfloat green,
2603                                GLfloat blue, GLfloat alpha )
2604{
2605   GLint r = (GLint) (red   * 255.0F);
2606   GLint g = (GLint) (green * 255.0F);
2607   GLint b = (GLint) (blue  * 255.0F);
2608   GLint a = (GLint) (alpha * 255.0F);
2609
2610   switch (xmesa->pixelformat) {
2611      case PF_Index:
2612         return 0;
2613      case PF_Truecolor:
2614         {
2615            unsigned long p;
2616            PACK_TRUECOLOR( p, r, g, b );
2617            return p;
2618         }
2619      case PF_8A8B8G8R:
2620         return PACK_8A8B8G8R( r, g, b, a );
2621      case PF_8R8G8B:
2622         return PACK_8R8G8B( r, g, b );
2623      case PF_5R6G5B:
2624         return PACK_5R6G5B( r, g, b );
2625      case PF_Dither:
2626         {
2627            DITHER_SETUP;
2628            return DITHER( x, y, r, g, b );
2629         }
2630      case PF_1Bit:
2631         /* 382 = (3*255)/2 */
2632         return ((r+g+b) > 382) ^ xmesa->xm_visual->bitFlip;
2633      case PF_HPCR:
2634         return DITHER_HPCR(x, y, r, g, b);
2635      case PF_Lookup:
2636         {
2637            LOOKUP_SETUP;
2638            return LOOKUP( r, g, b );
2639         }
2640      case PF_Grayscale:
2641         return GRAY_RGB( r, g, b );
2642      case PF_Dither_5R6G5B:
2643         /* fall through */
2644      case PF_Dither_True:
2645         {
2646            unsigned long p;
2647            PACK_TRUEDITHER(p, x, y, r, g, b);
2648            return p;
2649         }
2650      default:
2651         _mesa_problem(NULL, "Bad pixel format in XMesaDitherColor");
2652   }
2653   return 0;
2654}
2655
2656
2657/*
2658 * This is typically called when the window size changes and we need
2659 * to reallocate the buffer's back/depth/stencil/accum buffers.
2660 */
2661void XMesaResizeBuffers( XMesaBuffer b )
2662{
2663   xmesa_resize_buffers( &(b->mesa_buffer) );
2664
2665}
2666
2667