xm_api.c revision 8d51bbf2a3b4bac379855c84ebeed86c3578d0c6
1/*
2 * Mesa 3-D graphics library
3 * Version:  6.3
4 *
5 * Copyright (C) 1999-2005  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 * Apply gamma correction to an intensity value in [0..max].  Return the
225 * new intensity value.
226 */
227static GLint gamma_adjust( GLfloat gamma, GLint value, GLint max )
228{
229   if (gamma == 1.0) {
230      return value;
231   }
232   else {
233      double x = (double) value / (double) max;
234      return IROUND_POS((GLfloat) max * _mesa_pow(x, 1.0F/gamma));
235   }
236}
237
238
239
240/*
241 * Return the true number of bits per pixel for XImages.
242 * For example, if we request a 24-bit deep visual we may actually need/get
243 * 32bpp XImages.  This function returns the appropriate bpp.
244 * Input:  dpy - the X display
245 *         visinfo - desribes the visual to be used for XImages
246 * Return:  true number of bits per pixel for XImages
247 */
248#ifdef XFree86Server
249
250static int bits_per_pixel( XMesaVisual xmv )
251{
252   const int depth = xmv->nplanes;
253   int i;
254   for (i = 0; i < screenInfo.numPixmapFormats; i++) {
255      if (screenInfo.formats[i].depth == depth)
256         return screenInfo.formats[i].bitsPerPixel;
257   }
258   return depth;  /* should never get here, but this should be safe */
259}
260
261#else
262
263static int bits_per_pixel( XMesaVisual xmv )
264{
265   XMesaDisplay *dpy = xmv->display;
266   XMesaVisualInfo visinfo = xmv->visinfo;
267   XMesaImage *img;
268   int bitsPerPixel;
269   /* Create a temporary XImage */
270   img = XCreateImage( dpy, visinfo->visual, visinfo->depth,
271		       ZPixmap, 0,           /*format, offset*/
272		       (char*) MALLOC(8),    /*data*/
273		       1, 1,                 /*width, height*/
274		       32,                   /*bitmap_pad*/
275		       0                     /*bytes_per_line*/
276                     );
277   assert(img);
278   /* grab the bits/pixel value */
279   bitsPerPixel = img->bits_per_pixel;
280   /* free the XImage */
281   FREE( img->data );
282   img->data = NULL;
283   XMesaDestroyImage( img );
284   return bitsPerPixel;
285}
286#endif
287
288
289
290/*
291 * Determine if a given X window ID is valid (window exists).
292 * Do this by calling XGetWindowAttributes() for the window and
293 * checking if we catch an X error.
294 * Input:  dpy - the display
295 *         win - the window to check for existance
296 * Return:  GL_TRUE - window exists
297 *          GL_FALSE - window doesn't exist
298 */
299#ifndef XFree86Server
300static GLboolean WindowExistsFlag;
301
302static int window_exists_err_handler( XMesaDisplay* dpy, XErrorEvent* xerr )
303{
304   (void) dpy;
305   if (xerr->error_code == BadWindow) {
306      WindowExistsFlag = GL_FALSE;
307   }
308   return 0;
309}
310
311static GLboolean window_exists( XMesaDisplay *dpy, Window win )
312{
313   XWindowAttributes wa;
314   int (*old_handler)( XMesaDisplay*, XErrorEvent* );
315   WindowExistsFlag = GL_TRUE;
316   old_handler = XSetErrorHandler(window_exists_err_handler);
317   XGetWindowAttributes( dpy, win, &wa ); /* dummy request */
318   XSetErrorHandler(old_handler);
319   return WindowExistsFlag;
320}
321#endif
322
323
324
325/**********************************************************************/
326/*****                Linked list of XMesaBuffers                 *****/
327/**********************************************************************/
328
329static XMesaBuffer XMesaBufferList = NULL;
330
331
332/**
333 * Allocate a new XMesaBuffer, initialize basic fields and add to
334 * the list of all buffers.
335 */
336static XMesaBuffer
337alloc_xmesa_buffer(XMesaVisual vis, BufferType type, XMesaColormap cmap)
338{
339   XMesaBuffer b = (XMesaBuffer) CALLOC_STRUCT(xmesa_buffer);
340   if (b) {
341      b->display = vis->display;
342      b->xm_visual = vis;
343      b->type = type;
344      b->cmap = cmap;
345
346      _mesa_initialize_framebuffer(&b->mesa_buffer,
347                                   &vis->mesa_visual,
348                                   vis->mesa_visual.depthBits > 0,
349                                   vis->mesa_visual.stencilBits > 0,
350                                   vis->mesa_visual.accumRedBits +
351                                   vis->mesa_visual.accumGreenBits +
352                                   vis->mesa_visual.accumBlueBits > 0,
353                                   vis->mesa_visual.alphaBits > 0
354                                   /*v->mesa_visual.numAuxBuffers > 0*/ );
355      /* XXX hack */
356      if (vis->mesa_visual.numAuxBuffers > 0)
357         b->mesa_buffer.UseSoftwareAuxBuffers = GL_TRUE;
358
359      /* determine back buffer implementation */
360      if (vis->mesa_visual.doubleBufferMode) {
361         if (vis->ximage_flag) {
362            b->db_state = BACK_XIMAGE;
363         }
364         else {
365            b->db_state = BACK_PIXMAP;
366         }
367      }
368      else {
369         b->db_state = 0;
370      }
371
372      /* insert into linked list */
373      b->Next = XMesaBufferList;
374      XMesaBufferList = b;
375   }
376   return b;
377}
378
379
380/*
381 * Find an XMesaBuffer by matching X display and colormap but NOT matching
382 * the notThis buffer.
383 */
384static XMesaBuffer find_xmesa_buffer(XMesaDisplay *dpy,
385                                     XMesaColormap cmap,
386                                     XMesaBuffer notThis)
387{
388   XMesaBuffer b;
389   for (b=XMesaBufferList; b; b=b->Next) {
390      if (b->display==dpy && b->cmap==cmap && b!=notThis) {
391         return b;
392      }
393   }
394   return NULL;
395}
396
397
398/*
399 * Free an XMesaBuffer, remove from linked list, perhaps free X colormap
400 * entries.
401 */
402static void free_xmesa_buffer(int client, XMesaBuffer buffer)
403{
404   XMesaBuffer prev = NULL, b;
405   (void) client;
406   for (b=XMesaBufferList; b; b=b->Next) {
407      if (b==buffer) {
408         /* unlink bufer from list */
409         if (prev)
410            prev->Next = buffer->Next;
411         else
412            XMesaBufferList = buffer->Next;
413         /* Check to free X colors */
414         if (buffer->num_alloced>0) {
415            /* If no other buffer uses this X colormap then free the colors. */
416            if (!find_xmesa_buffer(buffer->display, buffer->cmap, buffer)) {
417#ifdef XFree86Server
418               (void)FreeColors(buffer->cmap, client,
419				buffer->num_alloced, buffer->alloced_colors,
420				0);
421#else
422               XFreeColors(buffer->display, buffer->cmap,
423                           buffer->alloced_colors, buffer->num_alloced, 0);
424#endif
425            }
426         }
427
428         _mesa_free_framebuffer_data(&buffer->mesa_buffer);
429         FREE(buffer);
430
431         return;
432      }
433      /* continue search */
434      prev = b;
435   }
436   /* buffer not found in XMesaBufferList */
437   _mesa_problem(NULL,"free_xmesa_buffer() - buffer not found\n");
438}
439
440
441/* Copy X color table stuff from one XMesaBuffer to another. */
442static void copy_colortable_info(XMesaBuffer dst, const XMesaBuffer src)
443{
444   MEMCPY(dst->color_table, src->color_table, sizeof(src->color_table));
445   MEMCPY(dst->pixel_to_r, src->pixel_to_r, sizeof(src->pixel_to_r));
446   MEMCPY(dst->pixel_to_g, src->pixel_to_g, sizeof(src->pixel_to_g));
447   MEMCPY(dst->pixel_to_b, src->pixel_to_b, sizeof(src->pixel_to_b));
448   dst->num_alloced = src->num_alloced;
449   MEMCPY(dst->alloced_colors, src->alloced_colors,
450          sizeof(src->alloced_colors));
451}
452
453
454
455/**********************************************************************/
456/*****                   Misc Private Functions                   *****/
457/**********************************************************************/
458
459
460/*
461 * Return number of bits set in n.
462 */
463static int bitcount( unsigned long n )
464{
465   int bits;
466   for (bits=0; n>0; n=n>>1) {
467      if (n&1) {
468         bits++;
469      }
470   }
471   return bits;
472}
473
474
475
476/*
477 * Allocate a shared memory XImage back buffer for the given XMesaBuffer.
478 * Return:  GL_TRUE if success, GL_FALSE if error
479 */
480#ifndef XFree86Server
481static GLboolean alloc_shm_back_buffer( XMesaBuffer b )
482{
483#ifdef USE_XSHM
484   /*
485    * We have to do a _lot_ of error checking here to be sure we can
486    * really use the XSHM extension.  It seems different servers trigger
487    * errors at different points if the extension won't work.  Therefore
488    * we have to be very careful...
489    */
490   GC gc;
491   int (*old_handler)( XMesaDisplay *, XErrorEvent * );
492
493   if (b->mesa_buffer.Width == 0 || b->mesa_buffer.Height == 0) {
494      /* this will be true the first time we're called on 'b' */
495      return GL_FALSE;
496   }
497
498   b->backimage = XShmCreateImage(b->xm_visual->display,
499                                  b->xm_visual->visinfo->visual,
500                                  b->xm_visual->visinfo->depth,
501                                  ZPixmap, NULL, &b->shminfo,
502                                  b->mesa_buffer.Width, b->mesa_buffer.Height);
503   if (b->backimage == NULL) {
504      _mesa_warning(NULL, "alloc_back_buffer: Shared memory error (XShmCreateImage), disabling.");
505      b->shm = 0;
506      return GL_FALSE;
507   }
508
509   b->shminfo.shmid = shmget( IPC_PRIVATE, b->backimage->bytes_per_line
510			     * b->backimage->height, IPC_CREAT|0777 );
511   if (b->shminfo.shmid < 0) {
512      _mesa_warning(NULL, "shmget failed while allocating back buffer");
513      XDestroyImage( b->backimage );
514      b->backimage = NULL;
515      _mesa_warning(NULL, "alloc_back_buffer: Shared memory error (shmget), disabling.");
516      b->shm = 0;
517      return GL_FALSE;
518   }
519
520   b->shminfo.shmaddr = b->backimage->data
521                      = (char*)shmat( b->shminfo.shmid, 0, 0 );
522   if (b->shminfo.shmaddr == (char *) -1) {
523      _mesa_warning(NULL, "shmat() failed while allocating back buffer");
524      XDestroyImage( b->backimage );
525      shmctl( b->shminfo.shmid, IPC_RMID, 0 );
526      b->backimage = NULL;
527      _mesa_warning(NULL, "alloc_back_buffer: Shared memory error (shmat), disabling.");
528      b->shm = 0;
529      return GL_FALSE;
530   }
531
532   b->shminfo.readOnly = False;
533   mesaXErrorFlag = 0;
534   old_handler = XSetErrorHandler( mesaHandleXError );
535   /* This may trigger the X protocol error we're ready to catch: */
536   XShmAttach( b->xm_visual->display, &b->shminfo );
537   XSync( b->xm_visual->display, False );
538
539   if (mesaXErrorFlag) {
540      /* we are on a remote display, this error is normal, don't print it */
541      XFlush( b->xm_visual->display );
542      mesaXErrorFlag = 0;
543      XDestroyImage( b->backimage );
544      shmdt( b->shminfo.shmaddr );
545      shmctl( b->shminfo.shmid, IPC_RMID, 0 );
546      b->backimage = NULL;
547      b->shm = 0;
548      (void) XSetErrorHandler( old_handler );
549      return GL_FALSE;
550   }
551
552   shmctl( b->shminfo.shmid, IPC_RMID, 0 ); /* nobody else needs it */
553
554   /* Finally, try an XShmPutImage to be really sure the extension works */
555   gc = XCreateGC( b->xm_visual->display, b->frontbuffer, 0, NULL );
556   XShmPutImage( b->xm_visual->display, b->frontbuffer, gc,
557		 b->backimage, 0, 0, 0, 0, 1, 1 /*one pixel*/, False );
558   XSync( b->xm_visual->display, False );
559   XFreeGC( b->xm_visual->display, gc );
560   (void) XSetErrorHandler( old_handler );
561   if (mesaXErrorFlag) {
562      XFlush( b->xm_visual->display );
563      mesaXErrorFlag = 0;
564      XDestroyImage( b->backimage );
565      shmdt( b->shminfo.shmaddr );
566      shmctl( b->shminfo.shmid, IPC_RMID, 0 );
567      b->backimage = NULL;
568      b->shm = 0;
569      return GL_FALSE;
570   }
571
572   if (b->backimage) {
573      int height = b->backimage->height;
574      /* Needed by PIXELADDR1 macro */
575      b->ximage_width1 = b->backimage->bytes_per_line;
576      b->ximage_origin1 = (GLubyte *) b->backimage->data
577                        + b->ximage_width1 * (height-1);
578      /* Needed by PIXELADDR2 macro */
579      b->ximage_width2 = b->backimage->bytes_per_line / 2;
580      b->ximage_origin2 = (GLushort *) b->backimage->data
581                        + b->ximage_width2 * (height-1);
582      /* Needed by PIXELADDR3 macro */
583      b->ximage_width3 = b->backimage->bytes_per_line;
584      b->ximage_origin3 = (GLubyte *) b->backimage->data
585                        + b->ximage_width3 * (height-1);
586      /* Needed by PIXELADDR4 macro */
587      b->ximage_width4 = b->backimage->width;
588      b->ximage_origin4 = (GLuint *) b->backimage->data
589                        + b->ximage_width4 * (height-1);
590   }
591
592   return GL_TRUE;
593#else
594   /* Can't compile XSHM support */
595   return GL_FALSE;
596#endif
597}
598#endif
599
600
601
602/*
603 * Setup an off-screen pixmap or Ximage to use as the back buffer.
604 * Input:  b - the X/Mesa buffer
605 */
606void xmesa_alloc_back_buffer( XMesaBuffer b )
607{
608   if (b->db_state==BACK_XIMAGE) {
609      /* Deallocate the old backimage, if any */
610      if (b->backimage) {
611#if defined(USE_XSHM) && !defined(XFree86Server)
612	 if (b->shm) {
613	    XShmDetach( b->xm_visual->display, &b->shminfo );
614	    XDestroyImage( b->backimage );
615	    shmdt( b->shminfo.shmaddr );
616	 }
617	 else
618#endif
619	   XMesaDestroyImage( b->backimage );
620	 b->backimage = NULL;
621      }
622
623      /* Allocate new back buffer */
624#ifdef XFree86Server
625      {
626	 /* Allocate a regular XImage for the back buffer. */
627	 b->backimage = XMesaCreateImage(b->xm_visual->BitsPerPixel,
628					 b->mesa_buffer.Width,
629                                         b->mesa_buffer.Height, NULL);
630#else
631      if (b->shm==0 || alloc_shm_back_buffer(b)==GL_FALSE) {
632	 /* Allocate a regular XImage for the back buffer. */
633	 b->backimage = XCreateImage( b->xm_visual->display,
634                                      b->xm_visual->visinfo->visual,
635                                      GET_VISUAL_DEPTH(b->xm_visual),
636				      ZPixmap, 0,   /* format, offset */
637				      NULL,
638                                      b->mesa_buffer.Width,
639                                      b->mesa_buffer.Height,
640				      8, 0 );  /* pad, bytes_per_line */
641#endif
642	 if (!b->backimage) {
643	    _mesa_warning(NULL, "alloc_back_buffer: XCreateImage failed.");
644	 }
645         b->backimage->data = (char *) MALLOC( b->backimage->height
646                                             * b->backimage->bytes_per_line );
647         if (!b->backimage->data) {
648            _mesa_warning(NULL, "alloc_back_buffer: MALLOC failed.");
649            XMesaDestroyImage( b->backimage );
650            b->backimage = NULL;
651         }
652      }
653      b->backpixmap = None;
654   }
655   else if (b->db_state==BACK_PIXMAP) {
656      XMesaPixmap old_pixmap = b->backpixmap;
657      int width = b->mesa_buffer.Width, height = b->mesa_buffer.Height;
658
659      if (!width)
660         width = 1;
661      if (!height)
662         height = 1;
663
664      /* Free the old back pixmap */
665      if (b->backpixmap) {
666	 XMesaFreePixmap( b->xm_visual->display, b->backpixmap );
667      }
668      /* Allocate new back pixmap */
669      b->backpixmap = XMesaCreatePixmap( b->xm_visual->display, b->frontbuffer,
670					 width, height,
671					 GET_VISUAL_DEPTH(b->xm_visual) );
672      b->backimage = NULL;
673      /* update other references to backpixmap */
674      if (b->buffer==(XMesaDrawable)old_pixmap) {
675	 b->buffer = (XMesaDrawable)b->backpixmap;
676      }
677   }
678}
679
680
681
682/*
683 * A replacement for XAllocColor.  This function should never
684 * fail to allocate a color.  When XAllocColor fails, we return
685 * the nearest matching color.  If we have to allocate many colors
686 * this function isn't too efficient; the XQueryColors() could be
687 * done just once.
688 * Written by Michael Pichler, Brian Paul, Mark Kilgard
689 * Input:  dpy - X display
690 *         cmap - X colormap
691 *         cmapSize - size of colormap
692 * In/Out: color - the XColor struct
693 * Output:  exact - 1=exact color match, 0=closest match
694 *          alloced - 1=XAlloc worked, 0=XAlloc failed
695 */
696static void
697noFaultXAllocColor( int client,
698                    XMesaDisplay *dpy,
699                    XMesaColormap cmap,
700                    int cmapSize,
701                    XMesaColor *color,
702                    int *exact, int *alloced )
703{
704#ifdef XFree86Server
705   Pixel *ppixIn;
706   xrgb *ctable;
707#else
708   /* we'll try to cache ctable for better remote display performance */
709   static Display *prevDisplay = NULL;
710   static XMesaColormap prevCmap = 0;
711   static int prevCmapSize = 0;
712   static XMesaColor *ctable = NULL;
713#endif
714   XMesaColor subColor;
715   int i, bestmatch;
716   double mindist;       /* 3*2^16^2 exceeds long int precision. */
717
718   (void) client;
719
720   /* First try just using XAllocColor. */
721#ifdef XFree86Server
722   if (AllocColor(cmap,
723		  &color->red, &color->green, &color->blue,
724		  &color->pixel,
725		  client) == Success) {
726#else
727   if (XAllocColor(dpy, cmap, color)) {
728#endif
729      *exact = 1;
730      *alloced = 1;
731      return;
732   }
733
734   /* Alloc failed, search for closest match */
735
736   /* Retrieve color table entries. */
737   /* XXX alloca candidate. */
738#ifdef XFree86Server
739   ppixIn = (Pixel *) MALLOC(cmapSize * sizeof(Pixel));
740   ctable = (xrgb *) MALLOC(cmapSize * sizeof(xrgb));
741   for (i = 0; i < cmapSize; i++) {
742      ppixIn[i] = i;
743   }
744   QueryColors(cmap, cmapSize, ppixIn, ctable);
745#else
746   if (prevDisplay != dpy || prevCmap != cmap
747       || prevCmapSize != cmapSize || !ctable) {
748      /* free previously cached color table */
749      if (ctable)
750         FREE(ctable);
751      /* Get the color table from X */
752      ctable = (XMesaColor *) MALLOC(cmapSize * sizeof(XMesaColor));
753      assert(ctable);
754      for (i = 0; i < cmapSize; i++) {
755         ctable[i].pixel = i;
756      }
757      XQueryColors(dpy, cmap, ctable, cmapSize);
758      prevDisplay = dpy;
759      prevCmap = cmap;
760      prevCmapSize = cmapSize;
761   }
762#endif
763
764   /* Find best match. */
765   bestmatch = -1;
766   mindist = 0.0;
767   for (i = 0; i < cmapSize; i++) {
768      double dr = 0.30 * ((double) color->red - (double) ctable[i].red);
769      double dg = 0.59 * ((double) color->green - (double) ctable[i].green);
770      double db = 0.11 * ((double) color->blue - (double) ctable[i].blue);
771      double dist = dr * dr + dg * dg + db * db;
772      if (bestmatch < 0 || dist < mindist) {
773         bestmatch = i;
774         mindist = dist;
775      }
776   }
777
778   /* Return result. */
779   subColor.red   = ctable[bestmatch].red;
780   subColor.green = ctable[bestmatch].green;
781   subColor.blue  = ctable[bestmatch].blue;
782   /* Try to allocate the closest match color.  This should only
783    * fail if the cell is read/write.  Otherwise, we're incrementing
784    * the cell's reference count.
785    */
786#ifdef XFree86Server
787   if (AllocColor(cmap,
788		  &subColor.red, &subColor.green, &subColor.blue,
789		  &subColor.pixel,
790		  client) == Success) {
791#else
792   if (XAllocColor(dpy, cmap, &subColor)) {
793#endif
794      *alloced = 1;
795   }
796   else {
797      /* do this to work around a problem reported by Frank Ortega */
798      subColor.pixel = (unsigned long) bestmatch;
799      subColor.red   = ctable[bestmatch].red;
800      subColor.green = ctable[bestmatch].green;
801      subColor.blue  = ctable[bestmatch].blue;
802      subColor.flags = DoRed | DoGreen | DoBlue;
803      *alloced = 0;
804   }
805#ifdef XFree86Server
806   FREE(ppixIn);
807   FREE(ctable);
808#else
809   /* don't free table, save it for next time */
810#endif
811
812   *color = subColor;
813   *exact = 0;
814}
815
816
817
818
819/*
820 * Do setup for PF_GRAYSCALE pixel format.
821 * Note that buffer may be NULL.
822 */
823static GLboolean setup_grayscale( int client, XMesaVisual v,
824                                  XMesaBuffer buffer, XMesaColormap cmap )
825{
826   if (GET_VISUAL_DEPTH(v)<4 || GET_VISUAL_DEPTH(v)>16) {
827      return GL_FALSE;
828   }
829
830   if (buffer) {
831      XMesaBuffer prevBuffer;
832
833      if (!cmap) {
834         return GL_FALSE;
835      }
836
837      prevBuffer = find_xmesa_buffer(v->display, cmap, buffer);
838      if (prevBuffer &&
839          (buffer->xm_visual->mesa_visual.rgbMode ==
840           prevBuffer->xm_visual->mesa_visual.rgbMode)) {
841         /* Copy colormap stuff from previous XMesaBuffer which uses same
842          * X colormap.  Do this to avoid time spent in noFaultXAllocColor.
843          */
844         copy_colortable_info(buffer, prevBuffer);
845      }
846      else {
847         /* Allocate 256 shades of gray */
848         int gray;
849         int colorsfailed = 0;
850         for (gray=0;gray<256;gray++) {
851            GLint r = gamma_adjust( v->RedGamma,   gray, 255 );
852            GLint g = gamma_adjust( v->GreenGamma, gray, 255 );
853            GLint b = gamma_adjust( v->BlueGamma,  gray, 255 );
854            int exact, alloced;
855            XMesaColor xcol;
856            xcol.red   = (r << 8) | r;
857            xcol.green = (g << 8) | g;
858            xcol.blue  = (b << 8) | b;
859            noFaultXAllocColor( client, v->display,
860                                cmap, GET_COLORMAP_SIZE(v),
861                                &xcol, &exact, &alloced );
862            if (!exact) {
863               colorsfailed++;
864            }
865            if (alloced) {
866               assert(buffer->num_alloced<256);
867               buffer->alloced_colors[buffer->num_alloced] = xcol.pixel;
868               buffer->num_alloced++;
869            }
870
871            /*OLD
872            assert(gray < 576);
873            buffer->color_table[gray*3+0] = xcol.pixel;
874            buffer->color_table[gray*3+1] = xcol.pixel;
875            buffer->color_table[gray*3+2] = xcol.pixel;
876            assert(xcol.pixel < 65536);
877            buffer->pixel_to_r[xcol.pixel] = gray * 30 / 100;
878            buffer->pixel_to_g[xcol.pixel] = gray * 59 / 100;
879            buffer->pixel_to_b[xcol.pixel] = gray * 11 / 100;
880            */
881            buffer->color_table[gray] = xcol.pixel;
882            assert(xcol.pixel < 65536);
883            buffer->pixel_to_r[xcol.pixel] = gray;
884            buffer->pixel_to_g[xcol.pixel] = gray;
885            buffer->pixel_to_b[xcol.pixel] = gray;
886         }
887
888         if (colorsfailed && _mesa_getenv("MESA_DEBUG")) {
889            _mesa_warning(NULL,
890                  "Note: %d out of 256 needed colors do not match exactly.\n",
891                  colorsfailed );
892         }
893      }
894   }
895
896   v->dithered_pf = PF_Grayscale;
897   v->undithered_pf = PF_Grayscale;
898   return GL_TRUE;
899}
900
901
902
903/*
904 * Setup RGB rendering for a window with a PseudoColor, StaticColor,
905 * or 8-bit TrueColor visual visual.  We try to allocate a palette of 225
906 * colors (5 red, 9 green, 5 blue) and dither to approximate a 24-bit RGB
907 * color.  While this function was originally designed just for 8-bit
908 * visuals, it has also proven to work from 4-bit up to 16-bit visuals.
909 * Dithering code contributed by Bob Mercier.
910 */
911static GLboolean setup_dithered_color( int client, XMesaVisual v,
912                                       XMesaBuffer buffer, XMesaColormap cmap )
913{
914   if (GET_VISUAL_DEPTH(v)<4 || GET_VISUAL_DEPTH(v)>16) {
915      return GL_FALSE;
916   }
917
918   if (buffer) {
919      XMesaBuffer prevBuffer;
920
921      if (!cmap) {
922         return GL_FALSE;
923      }
924
925      prevBuffer = find_xmesa_buffer(v->display, cmap, buffer);
926      if (prevBuffer &&
927          (buffer->xm_visual->mesa_visual.rgbMode ==
928           prevBuffer->xm_visual->mesa_visual.rgbMode)) {
929         /* Copy colormap stuff from previous, matching XMesaBuffer.
930          * Do this to avoid time spent in noFaultXAllocColor.
931          */
932         copy_colortable_info(buffer, prevBuffer);
933      }
934      else {
935         /* Allocate X colors and initialize color_table[], red_table[], etc */
936         int r, g, b, i;
937         int colorsfailed = 0;
938         for (r = 0; r < DITH_R; r++) {
939            for (g = 0; g < DITH_G; g++) {
940               for (b = 0; b < DITH_B; b++) {
941                  XMesaColor xcol;
942                  int exact, alloced;
943                  xcol.red  =gamma_adjust(v->RedGamma,   r*65535/(DITH_R-1),65535);
944                  xcol.green=gamma_adjust(v->GreenGamma, g*65535/(DITH_G-1),65535);
945                  xcol.blue =gamma_adjust(v->BlueGamma,  b*65535/(DITH_B-1),65535);
946                  noFaultXAllocColor( client, v->display,
947                                      cmap, GET_COLORMAP_SIZE(v),
948                                      &xcol, &exact, &alloced );
949                  if (!exact) {
950                     colorsfailed++;
951                  }
952                  if (alloced) {
953                     assert(buffer->num_alloced<256);
954                     buffer->alloced_colors[buffer->num_alloced] = xcol.pixel;
955                     buffer->num_alloced++;
956                  }
957                  i = DITH_MIX( r, g, b );
958                  assert(i < 576);
959                  buffer->color_table[i] = xcol.pixel;
960                  assert(xcol.pixel < 65536);
961                  buffer->pixel_to_r[xcol.pixel] = r * 255 / (DITH_R-1);
962                  buffer->pixel_to_g[xcol.pixel] = g * 255 / (DITH_G-1);
963                  buffer->pixel_to_b[xcol.pixel] = b * 255 / (DITH_B-1);
964               }
965            }
966         }
967
968         if (colorsfailed && _mesa_getenv("MESA_DEBUG")) {
969            _mesa_warning(NULL,
970                  "Note: %d out of %d needed colors do not match exactly.\n",
971                  colorsfailed, DITH_R * DITH_G * DITH_B );
972         }
973      }
974   }
975
976   v->dithered_pf = PF_Dither;
977   v->undithered_pf = PF_Lookup;
978   return GL_TRUE;
979}
980
981
982/*
983 * Setup for Hewlett Packard Color Recovery 8-bit TrueColor mode.
984 * HPCR simulates 24-bit color fidelity with an 8-bit frame buffer.
985 * Special dithering tables have to be initialized.
986 */
987static void setup_8bit_hpcr( XMesaVisual v )
988{
989   /* HP Color Recovery contributed by:  Alex De Bruyn (ad@lms.be)
990    * To work properly, the atom _HP_RGB_SMOOTH_MAP_LIST must be defined
991    * on the root window AND the colormap obtainable by XGetRGBColormaps
992    * for that atom must be set on the window.  (see also tkInitWindow)
993    * If that colormap is not set, the output will look stripy.
994    */
995
996   /* Setup color tables with gamma correction */
997   int i;
998   double g;
999
1000   g = 1.0 / v->RedGamma;
1001   for (i=0; i<256; i++) {
1002      GLint red = IROUND_POS(255.0 * _mesa_pow( hpcr_rgbTbl[0][i]/255.0, g ));
1003      v->hpcr_rgbTbl[0][i] = CLAMP( red, 16, 239 );
1004   }
1005
1006   g = 1.0 / v->GreenGamma;
1007   for (i=0; i<256; i++) {
1008      GLint green = IROUND_POS(255.0 * _mesa_pow( hpcr_rgbTbl[1][i]/255.0, g ));
1009      v->hpcr_rgbTbl[1][i] = CLAMP( green, 16, 239 );
1010   }
1011
1012   g = 1.0 / v->BlueGamma;
1013   for (i=0; i<256; i++) {
1014      GLint blue = IROUND_POS(255.0 * _mesa_pow( hpcr_rgbTbl[2][i]/255.0, g ));
1015      v->hpcr_rgbTbl[2][i] = CLAMP( blue, 32, 223 );
1016   }
1017   v->undithered_pf = PF_HPCR;  /* can't really disable dithering for now */
1018   v->dithered_pf = PF_HPCR;
1019
1020   /* which method should I use to clear */
1021   /* GL_FALSE: keep the ordinary method  */
1022   /* GL_TRUE : clear with dither pattern */
1023   v->hpcr_clear_flag = _mesa_getenv("MESA_HPCR_CLEAR") ? GL_TRUE : GL_FALSE;
1024
1025   if (v->hpcr_clear_flag) {
1026      v->hpcr_clear_pixmap = XMesaCreatePixmap(v->display,
1027                                               DefaultRootWindow(v->display),
1028                                               16, 2, 8);
1029#ifndef XFree86Server
1030      v->hpcr_clear_ximage = XGetImage(v->display, v->hpcr_clear_pixmap,
1031                                       0, 0, 16, 2, AllPlanes, ZPixmap);
1032#endif
1033   }
1034}
1035
1036
1037/*
1038 * Setup RGB rendering for a window with a True/DirectColor visual.
1039 */
1040static void setup_truecolor( XMesaVisual v, XMesaBuffer buffer,
1041                             XMesaColormap cmap )
1042{
1043   unsigned long rmask, gmask, bmask;
1044   (void) buffer;
1045   (void) cmap;
1046
1047   /* Compute red multiplier (mask) and bit shift */
1048   v->rshift = 0;
1049   rmask = GET_REDMASK(v);
1050   while ((rmask & 1)==0) {
1051      v->rshift++;
1052      rmask = rmask >> 1;
1053   }
1054
1055   /* Compute green multiplier (mask) and bit shift */
1056   v->gshift = 0;
1057   gmask = GET_GREENMASK(v);
1058   while ((gmask & 1)==0) {
1059      v->gshift++;
1060      gmask = gmask >> 1;
1061   }
1062
1063   /* Compute blue multiplier (mask) and bit shift */
1064   v->bshift = 0;
1065   bmask = GET_BLUEMASK(v);
1066   while ((bmask & 1)==0) {
1067      v->bshift++;
1068      bmask = bmask >> 1;
1069   }
1070
1071   /*
1072    * Compute component-to-pixel lookup tables and dithering kernel
1073    */
1074   {
1075      static GLubyte kernel[16] = {
1076          0*16,  8*16,  2*16, 10*16,
1077         12*16,  4*16, 14*16,  6*16,
1078          3*16, 11*16,  1*16,  9*16,
1079         15*16,  7*16, 13*16,  5*16,
1080      };
1081      GLint rBits = bitcount(rmask);
1082      GLint gBits = bitcount(gmask);
1083      GLint bBits = bitcount(bmask);
1084      GLint maxBits;
1085      GLuint i;
1086
1087      /* convert pixel components in [0,_mask] to RGB values in [0,255] */
1088      for (i=0; i<=rmask; i++)
1089         v->PixelToR[i] = (unsigned char) ((i * 255) / rmask);
1090      for (i=0; i<=gmask; i++)
1091         v->PixelToG[i] = (unsigned char) ((i * 255) / gmask);
1092      for (i=0; i<=bmask; i++)
1093         v->PixelToB[i] = (unsigned char) ((i * 255) / bmask);
1094
1095      /* convert RGB values from [0,255] to pixel components */
1096
1097      for (i=0;i<256;i++) {
1098         GLint r = gamma_adjust(v->RedGamma,   i, 255);
1099         GLint g = gamma_adjust(v->GreenGamma, i, 255);
1100         GLint b = gamma_adjust(v->BlueGamma,  i, 255);
1101         v->RtoPixel[i] = (r >> (8-rBits)) << v->rshift;
1102         v->GtoPixel[i] = (g >> (8-gBits)) << v->gshift;
1103         v->BtoPixel[i] = (b >> (8-bBits)) << v->bshift;
1104      }
1105      /* overflow protection */
1106      for (i=256;i<512;i++) {
1107         v->RtoPixel[i] = v->RtoPixel[255];
1108         v->GtoPixel[i] = v->GtoPixel[255];
1109         v->BtoPixel[i] = v->BtoPixel[255];
1110      }
1111
1112      /* setup dithering kernel */
1113      maxBits = rBits;
1114      if (gBits > maxBits)  maxBits = gBits;
1115      if (bBits > maxBits)  maxBits = bBits;
1116      for (i=0;i<16;i++) {
1117         v->Kernel[i] = kernel[i] >> maxBits;
1118      }
1119
1120      v->undithered_pf = PF_Truecolor;
1121      v->dithered_pf = (GET_VISUAL_DEPTH(v)<24) ? PF_Dither_True : PF_Truecolor;
1122   }
1123
1124   /*
1125    * Now check for TrueColor visuals which we can optimize.
1126    */
1127   if (   GET_REDMASK(v)  ==0x0000ff
1128       && GET_GREENMASK(v)==0x00ff00
1129       && GET_BLUEMASK(v) ==0xff0000
1130       && CHECK_BYTE_ORDER(v)
1131       && v->BitsPerPixel==32
1132       && sizeof(GLuint)==4
1133       && v->RedGamma==1.0 && v->GreenGamma==1.0 && v->BlueGamma==1.0) {
1134      /* common 32 bpp config used on SGI, Sun */
1135      v->undithered_pf = v->dithered_pf = PF_8A8B8G8R;
1136   }
1137   else if (GET_REDMASK(v)  ==0xff0000
1138       &&   GET_GREENMASK(v)==0x00ff00
1139       &&   GET_BLUEMASK(v) ==0x0000ff
1140       && CHECK_BYTE_ORDER(v)
1141       && v->BitsPerPixel==32
1142       && sizeof(GLuint)==4
1143       && v->RedGamma==1.0 && v->GreenGamma==1.0 && v->BlueGamma==1.0) {
1144      /* common 32 bpp config used on Linux, HP, IBM */
1145      if (GET_VISUAL_DEPTH(v)==32)
1146	  v->undithered_pf = v->dithered_pf = PF_8A8R8G8B;
1147      else
1148	  v->undithered_pf = v->dithered_pf = PF_8R8G8B;
1149   }
1150   else if (GET_REDMASK(v)  ==0xff0000
1151       &&   GET_GREENMASK(v)==0x00ff00
1152       &&   GET_BLUEMASK(v) ==0x0000ff
1153       && CHECK_BYTE_ORDER(v)
1154       && v->BitsPerPixel==24
1155       && sizeof(GLuint)==4
1156       && v->RedGamma==1.0 && v->GreenGamma==1.0 && v->BlueGamma==1.0) {
1157      /* common packed 24 bpp config used on Linux */
1158      v->undithered_pf = v->dithered_pf = PF_8R8G8B24;
1159   }
1160   else if (GET_REDMASK(v)  ==0xf800
1161       &&   GET_GREENMASK(v)==0x07e0
1162       &&   GET_BLUEMASK(v) ==0x001f
1163       && CHECK_BYTE_ORDER(v)
1164       && v->BitsPerPixel==16
1165       && sizeof(GLushort)==2
1166       && v->RedGamma==1.0 && v->GreenGamma==1.0 && v->BlueGamma==1.0) {
1167      /* 5-6-5 color weight on common PC VGA boards */
1168      v->undithered_pf = PF_5R6G5B;
1169      v->dithered_pf = PF_Dither_5R6G5B;
1170   }
1171   else if (GET_REDMASK(v)  ==0xe0
1172       &&   GET_GREENMASK(v)==0x1c
1173       &&   GET_BLUEMASK(v) ==0x03
1174       && CHECK_FOR_HPCR(v)) {
1175      setup_8bit_hpcr( v );
1176   }
1177}
1178
1179
1180
1181/*
1182 * Setup RGB rendering for a window with a monochrome visual.
1183 */
1184static void setup_monochrome( XMesaVisual v, XMesaBuffer b )
1185{
1186   (void) b;
1187   v->dithered_pf = v->undithered_pf = PF_1Bit;
1188   /* if black=1 then we must flip pixel values */
1189   v->bitFlip = (GET_BLACK_PIXEL(v) != 0);
1190}
1191
1192
1193
1194/*
1195 * When a context is "made current" for the first time, we can finally
1196 * finish initializing the context's visual and buffer information.
1197 * Input:  v - the XMesaVisual to initialize
1198 *         b - the XMesaBuffer to initialize (may be NULL)
1199 *         rgb_flag - TRUE = RGBA mode, FALSE = color index mode
1200 *         window - the window/pixmap we're rendering into
1201 *         cmap - the colormap associated with the window/pixmap
1202 * Return:  GL_TRUE=success, GL_FALSE=failure
1203 */
1204static GLboolean initialize_visual_and_buffer( int client,
1205                                               XMesaVisual v,
1206                                               XMesaBuffer b,
1207                                               GLboolean rgb_flag,
1208                                               XMesaDrawable window,
1209                                               XMesaColormap cmap )
1210{
1211#ifndef XFree86Server
1212   XGCValues gcvalues;
1213#endif
1214
1215   if (b) {
1216      assert(b->xm_visual == v);
1217   }
1218
1219   /* Save true bits/pixel */
1220   v->BitsPerPixel = bits_per_pixel(v);
1221   assert(v->BitsPerPixel > 0);
1222
1223
1224   if (rgb_flag==GL_FALSE) {
1225      /* COLOR-INDEXED WINDOW:
1226       * Even if the visual is TrueColor or DirectColor we treat it as
1227       * being color indexed.  This is weird but might be useful to someone.
1228       */
1229      v->dithered_pf = v->undithered_pf = PF_Index;
1230      v->mesa_visual.indexBits = GET_VISUAL_DEPTH(v);
1231   }
1232   else {
1233      /* RGB WINDOW:
1234       * We support RGB rendering into almost any kind of visual.
1235       */
1236      const int xclass = v->mesa_visual.visualType;
1237      if (xclass==GLX_TRUE_COLOR || xclass==GLX_DIRECT_COLOR) {
1238	 setup_truecolor( v, b, cmap );
1239      }
1240      else if (xclass==GLX_STATIC_GRAY && GET_VISUAL_DEPTH(v)==1) {
1241	 setup_monochrome( v, b );
1242      }
1243      else if (xclass==GLX_GRAY_SCALE || xclass==GLX_STATIC_GRAY) {
1244         if (!setup_grayscale( client, v, b, cmap )) {
1245            return GL_FALSE;
1246         }
1247      }
1248      else if ((xclass==GLX_PSEUDO_COLOR || xclass==GLX_STATIC_COLOR)
1249               && GET_VISUAL_DEPTH(v)>=4 && GET_VISUAL_DEPTH(v)<=16) {
1250	 if (!setup_dithered_color( client, v, b, cmap )) {
1251            return GL_FALSE;
1252         }
1253      }
1254      else {
1255	 _mesa_warning(NULL, "XMesa: RGB mode rendering not supported in given visual.");
1256	 return GL_FALSE;
1257      }
1258      v->mesa_visual.indexBits = 0;
1259
1260      if (_mesa_getenv("MESA_NO_DITHER")) {
1261	 v->dithered_pf = v->undithered_pf;
1262      }
1263   }
1264
1265
1266   /*
1267    * If MESA_INFO env var is set print out some debugging info
1268    * which can help Brian figure out what's going on when a user
1269    * reports bugs.
1270    */
1271   if (_mesa_getenv("MESA_INFO")) {
1272      _mesa_printf("X/Mesa visual = %p\n", (void *) v);
1273      _mesa_printf("X/Mesa dithered pf = %u\n", v->dithered_pf);
1274      _mesa_printf("X/Mesa undithered pf = %u\n", v->undithered_pf);
1275      _mesa_printf("X/Mesa level = %d\n", v->mesa_visual.level);
1276      _mesa_printf("X/Mesa depth = %d\n", GET_VISUAL_DEPTH(v));
1277      _mesa_printf("X/Mesa bits per pixel = %d\n", v->BitsPerPixel);
1278   }
1279
1280   if (b && window) {
1281      /* Do window-specific initializations */
1282
1283      b->frontbuffer = window;
1284
1285      /* Setup for single/double buffering */
1286      if (v->mesa_visual.doubleBufferMode) {
1287         /* Double buffered */
1288#ifndef XFree86Server
1289         b->shm = check_for_xshm( v->display );
1290#endif
1291         xmesa_alloc_back_buffer( b );
1292         if (b->db_state==BACK_PIXMAP) {
1293            b->buffer = (XMesaDrawable)b->backpixmap;
1294         }
1295         else {
1296            b->buffer = XIMAGE;
1297         }
1298      }
1299      else {
1300         /* Single Buffered */
1301         b->buffer = b->frontbuffer;
1302      }
1303
1304      /* X11 graphics contexts */
1305#ifdef XFree86Server
1306      b->gc = CreateScratchGC(v->display, window->depth);
1307#else
1308      b->gc = XCreateGC( v->display, window, 0, NULL );
1309#endif
1310      XMesaSetFunction( v->display, b->gc, GXcopy );
1311
1312      /* cleargc - for glClear() */
1313#ifdef XFree86Server
1314      b->cleargc = CreateScratchGC(v->display, window->depth);
1315#else
1316      b->cleargc = XCreateGC( v->display, window, 0, NULL );
1317#endif
1318      XMesaSetFunction( v->display, b->cleargc, GXcopy );
1319
1320      /*
1321       * Don't generate Graphics Expose/NoExpose events in swapbuffers().
1322       * Patch contributed by Michael Pichler May 15, 1995.
1323       */
1324#ifdef XFree86Server
1325      b->swapgc = CreateScratchGC(v->display, window->depth);
1326      {
1327	  CARD32 v[1];
1328	  v[0] = FALSE;
1329	  dixChangeGC(NullClient, b->swapgc, GCGraphicsExposures, v, NULL);
1330      }
1331#else
1332      gcvalues.graphics_exposures = False;
1333      b->swapgc = XCreateGC( v->display, window,
1334                              GCGraphicsExposures, &gcvalues);
1335#endif
1336      XMesaSetFunction( v->display, b->swapgc, GXcopy );
1337      /*
1338       * Set fill style and tile pixmap once for all for HPCR stuff
1339       * (instead of doing it each time in clear_color_HPCR_pixmap())
1340       * Initialize whole stuff
1341       * Patch contributed by Jacques Leroy March 8, 1998.
1342       */
1343      if (v->hpcr_clear_flag && b->buffer!=XIMAGE) {
1344	int i;
1345	for (i=0; i<16; i++)
1346        {
1347	   XMesaPutPixel(v->hpcr_clear_ximage, i, 0, 0);
1348	   XMesaPutPixel(v->hpcr_clear_ximage, i, 1, 0);
1349        }
1350        XMesaPutImage(b->display, (XMesaDrawable)v->hpcr_clear_pixmap,
1351		      b->cleargc, v->hpcr_clear_ximage, 0, 0, 0, 0, 16, 2);
1352	XMesaSetFillStyle( v->display, b->cleargc, FillTiled);
1353	XMesaSetTile( v->display, b->cleargc, v->hpcr_clear_pixmap );
1354      }
1355
1356      /* Initialize the row buffer XImage for use in write_color_span() */
1357#ifdef XFree86Server
1358      b->rowimage = XMesaCreateImage(GET_VISUAL_DEPTH(v), MAX_WIDTH, 1,
1359				     (char *)MALLOC(MAX_WIDTH*4));
1360#else
1361      b->rowimage = XCreateImage( v->display,
1362                                  v->visinfo->visual,
1363                                  v->visinfo->depth,
1364                                  ZPixmap, 0,           /*format, offset*/
1365                                  (char*) MALLOC(MAX_WIDTH*4),  /*data*/
1366                                  MAX_WIDTH, 1,         /*width, height*/
1367                                  32,                   /*bitmap_pad*/
1368                                  0                     /*bytes_per_line*/ );
1369#endif
1370      if (!b->rowimage)
1371         return GL_FALSE;
1372   }
1373
1374   return GL_TRUE;
1375}
1376
1377
1378
1379/*
1380 * Convert an RGBA color to a pixel value.
1381 */
1382unsigned long
1383xmesa_color_to_pixel( XMesaContext xmesa, GLubyte r, GLubyte g, GLubyte b, GLubyte a,
1384                      GLuint pixelFormat)
1385{
1386   switch (pixelFormat) {
1387      case PF_Index:
1388         return 0;
1389      case PF_Truecolor:
1390         {
1391            unsigned long p;
1392            PACK_TRUECOLOR( p, r, g, b );
1393            return p;
1394         }
1395      case PF_8A8B8G8R:
1396         return PACK_8A8B8G8R( r, g, b, a );
1397      case PF_8A8R8G8B:
1398         return PACK_8A8R8G8B( r, g, b, a );
1399      case PF_8R8G8B:
1400         /* fall through */
1401      case PF_8R8G8B24:
1402         return PACK_8R8G8B( r, g, b );
1403      case PF_5R6G5B:
1404         return PACK_5R6G5B( r, g, b );
1405      case PF_Dither:
1406         {
1407            DITHER_SETUP;
1408            return DITHER( 1, 0, r, g, b );
1409         }
1410      case PF_1Bit:
1411         /* 382 = (3*255)/2 */
1412         return ((r+g+b) > 382) ^ xmesa->xm_visual->bitFlip;
1413      case PF_HPCR:
1414         return DITHER_HPCR(1, 1, r, g, b);
1415      case PF_Lookup:
1416         {
1417            LOOKUP_SETUP;
1418            return LOOKUP( r, g, b );
1419         }
1420      case PF_Grayscale:
1421         return GRAY_RGB( r, g, b );
1422      case PF_Dither_True:
1423         /* fall through */
1424      case PF_Dither_5R6G5B:
1425         {
1426            unsigned long p;
1427            PACK_TRUEDITHER(p, 1, 0, r, g, b);
1428            return p;
1429         }
1430      default:
1431         _mesa_problem(NULL, "Bad pixel format in xmesa_color_to_pixel");
1432   }
1433   return 0;
1434}
1435
1436
1437#define NUM_VISUAL_TYPES   6
1438
1439/**
1440 * Convert an X visual type to a GLX visual type.
1441 *
1442 * \param visualType X visual type (i.e., \c TrueColor, \c StaticGray, etc.)
1443 *        to be converted.
1444 * \return If \c visualType is a valid X visual type, a GLX visual type will
1445 *         be returned.  Otherwise \c GLX_NONE will be returned.
1446 *
1447 * \note
1448 * This code was lifted directly from lib/GL/glx/glcontextmodes.c in the
1449 * DRI CVS tree.
1450 */
1451static GLint
1452xmesa_convert_from_x_visual_type( int visualType )
1453{
1454    static const int glx_visual_types[ NUM_VISUAL_TYPES ] = {
1455	GLX_STATIC_GRAY,  GLX_GRAY_SCALE,
1456	GLX_STATIC_COLOR, GLX_PSEUDO_COLOR,
1457	GLX_TRUE_COLOR,   GLX_DIRECT_COLOR
1458    };
1459
1460    return ( (unsigned) visualType < NUM_VISUAL_TYPES )
1461	? glx_visual_types[ visualType ] : GLX_NONE;
1462}
1463
1464
1465/**********************************************************************/
1466/*****                       Public Functions                     *****/
1467/**********************************************************************/
1468
1469
1470/*
1471 * Create a new X/Mesa visual.
1472 * Input:  display - X11 display
1473 *         visinfo - an XVisualInfo pointer
1474 *         rgb_flag - GL_TRUE = RGB mode,
1475 *                    GL_FALSE = color index mode
1476 *         alpha_flag - alpha buffer requested?
1477 *         db_flag - GL_TRUE = double-buffered,
1478 *                   GL_FALSE = single buffered
1479 *         stereo_flag - stereo visual?
1480 *         ximage_flag - GL_TRUE = use an XImage for back buffer,
1481 *                       GL_FALSE = use an off-screen pixmap for back buffer
1482 *         depth_size - requested bits/depth values, or zero
1483 *         stencil_size - requested bits/stencil values, or zero
1484 *         accum_red_size - requested bits/red accum values, or zero
1485 *         accum_green_size - requested bits/green accum values, or zero
1486 *         accum_blue_size - requested bits/blue accum values, or zero
1487 *         accum_alpha_size - requested bits/alpha accum values, or zero
1488 *         num_samples - number of samples/pixel if multisampling, or zero
1489 *         level - visual level, usually 0
1490 *         visualCaveat - ala the GLX extension, usually GLX_NONE
1491 * Return;  a new XMesaVisual or 0 if error.
1492 */
1493XMesaVisual XMesaCreateVisual( XMesaDisplay *display,
1494                               XMesaVisualInfo visinfo,
1495                               GLboolean rgb_flag,
1496                               GLboolean alpha_flag,
1497                               GLboolean db_flag,
1498                               GLboolean stereo_flag,
1499                               GLboolean ximage_flag,
1500                               GLint depth_size,
1501                               GLint stencil_size,
1502                               GLint accum_red_size,
1503                               GLint accum_green_size,
1504                               GLint accum_blue_size,
1505                               GLint accum_alpha_size,
1506                               GLint num_samples,
1507                               GLint level,
1508                               GLint visualCaveat )
1509{
1510   char *gamma;
1511   XMesaVisual v;
1512   GLint red_bits, green_bits, blue_bits, alpha_bits;
1513
1514   /* For debugging only */
1515   if (_mesa_getenv("MESA_XSYNC")) {
1516      /* This makes debugging X easier.
1517       * In your debugger, set a breakpoint on _XError to stop when an
1518       * X protocol error is generated.
1519       */
1520#ifdef XFree86Server
1521      /* NOT_NEEDED */
1522#else
1523      XSynchronize( display, 1 );
1524#endif
1525   }
1526
1527   v = (XMesaVisual) CALLOC_STRUCT(xmesa_visual);
1528   if (!v) {
1529      return NULL;
1530   }
1531
1532   /*
1533    * In the X server, NULL is passed in for the display.  It will have
1534    * to be set before using this visual.  See XMesaSetVisualDisplay()
1535    * below.
1536    */
1537   v->display = display;
1538
1539   /* Save a copy of the XVisualInfo struct because the user may XFREE()
1540    * the struct but we may need some of the information contained in it
1541    * at a later time.
1542    */
1543#ifndef XFree86Server
1544   v->visinfo = (XVisualInfo *) MALLOC(sizeof(*visinfo));
1545   if(!v->visinfo) {
1546      FREE(v);
1547      return NULL;
1548   }
1549   MEMCPY(v->visinfo, visinfo, sizeof(*visinfo));
1550#endif
1551
1552   /* check for MESA_GAMMA environment variable */
1553   gamma = _mesa_getenv("MESA_GAMMA");
1554   if (gamma) {
1555      v->RedGamma = v->GreenGamma = v->BlueGamma = 0.0;
1556      sscanf( gamma, "%f %f %f", &v->RedGamma, &v->GreenGamma, &v->BlueGamma );
1557      if (v->RedGamma<=0.0)    v->RedGamma = 1.0;
1558      if (v->GreenGamma<=0.0)  v->GreenGamma = v->RedGamma;
1559      if (v->BlueGamma<=0.0)   v->BlueGamma = v->RedGamma;
1560   }
1561   else {
1562      v->RedGamma = v->GreenGamma = v->BlueGamma = 1.0;
1563   }
1564
1565   v->ximage_flag = ximage_flag;
1566
1567#ifdef XFree86Server
1568   /* We could calculate these values by ourselves.  nplanes is either the sum
1569    * of the red, green, and blue bits or the number index bits.
1570    * ColormapEntries is either (1U << index_bits) or
1571    * (1U << max(redBits, greenBits, blueBits)).
1572    */
1573   v->nplanes = visinfo->nplanes;
1574   v->ColormapEntries = visinfo->ColormapEntries;
1575
1576   v->mesa_visual.redMask = visinfo->redMask;
1577   v->mesa_visual.greenMask = visinfo->greenMask;
1578   v->mesa_visual.blueMask = visinfo->blueMask;
1579   v->mesa_visual.visualID = visinfo->vid;
1580   v->mesa_visual.screen = 0; /* FIXME: What should be done here? */
1581#else
1582   v->mesa_visual.redMask = visinfo->red_mask;
1583   v->mesa_visual.greenMask = visinfo->green_mask;
1584   v->mesa_visual.blueMask = visinfo->blue_mask;
1585   v->mesa_visual.visualID = visinfo->visualid;
1586   v->mesa_visual.screen = visinfo->screen;
1587#endif
1588
1589#if defined(XFree86Server) || !(defined(__cplusplus) || defined(c_plusplus))
1590   v->mesa_visual.visualType = xmesa_convert_from_x_visual_type(visinfo->class);
1591#else
1592   v->mesa_visual.visualType = xmesa_convert_from_x_visual_type(visinfo->c_class);
1593#endif
1594
1595   v->mesa_visual.visualRating = visualCaveat;
1596
1597   (void) initialize_visual_and_buffer( 0, v, NULL, rgb_flag, 0, 0 );
1598
1599   {
1600      const int xclass = v->mesa_visual.visualType;
1601      if (xclass==GLX_TRUE_COLOR || xclass==GLX_DIRECT_COLOR) {
1602         red_bits   = bitcount(GET_REDMASK(v));
1603         green_bits = bitcount(GET_GREENMASK(v));
1604         blue_bits  = bitcount(GET_BLUEMASK(v));
1605         alpha_bits = 0;
1606      }
1607      else {
1608         /* this is an approximation */
1609         int depth;
1610         depth = GET_VISUAL_DEPTH(v);
1611         red_bits = depth / 3;
1612         depth -= red_bits;
1613         green_bits = depth / 2;
1614         depth -= green_bits;
1615         blue_bits = depth;
1616         alpha_bits = 0;
1617         assert( red_bits + green_bits + blue_bits == GET_VISUAL_DEPTH(v) );
1618      }
1619   }
1620
1621   if (alpha_flag && alpha_bits == 0)
1622      alpha_bits = 8;
1623
1624   _mesa_initialize_visual( &v->mesa_visual,
1625                            rgb_flag, db_flag, stereo_flag,
1626                            red_bits, green_bits,
1627                            blue_bits, alpha_bits,
1628                            v->mesa_visual.indexBits,
1629                            depth_size,
1630                            stencil_size,
1631                            accum_red_size, accum_green_size,
1632                            accum_blue_size, accum_alpha_size,
1633                            0 );
1634
1635   /* XXX minor hack */
1636   v->mesa_visual.level = level;
1637   return v;
1638}
1639
1640
1641void XMesaSetVisualDisplay( XMesaDisplay *dpy, XMesaVisual v )
1642{
1643    v->display = dpy;
1644}
1645
1646
1647void XMesaDestroyVisual( XMesaVisual v )
1648{
1649#ifndef XFree86Server
1650   FREE(v->visinfo);
1651#endif
1652   FREE(v);
1653}
1654
1655
1656
1657/**
1658 * Create a new XMesaContext.
1659 * \param v  the XMesaVisual
1660 * \param share_list  another XMesaContext with which to share display
1661 *                    lists or NULL if no sharing is wanted.
1662 * \return an XMesaContext or NULL if error.
1663 */
1664XMesaContext XMesaCreateContext( XMesaVisual v, XMesaContext share_list )
1665{
1666   static GLboolean firstTime = GL_TRUE;
1667   XMesaContext c;
1668   GLcontext *mesaCtx;
1669   struct dd_function_table functions;
1670   TNLcontext *tnl;
1671
1672   if (firstTime) {
1673      _glthread_INIT_MUTEX(_xmesa_lock);
1674      firstTime = GL_FALSE;
1675   }
1676
1677   /* Note: the XMesaContext contains a Mesa GLcontext struct (inheritance) */
1678   c = (XMesaContext) CALLOC_STRUCT(xmesa_context);
1679   if (!c)
1680      return NULL;
1681
1682   mesaCtx = &(c->mesa);
1683
1684   /* initialize with default driver functions, then plug in XMesa funcs */
1685   _mesa_init_driver_functions(&functions);
1686   xmesa_init_driver_functions(v, &functions);
1687   if (!_mesa_initialize_context(mesaCtx, &v->mesa_visual,
1688                      share_list ? &(share_list->mesa) : (GLcontext *) NULL,
1689                      &functions, (void *) c)) {
1690      FREE(c);
1691      return NULL;
1692   }
1693
1694   _mesa_enable_sw_extensions(mesaCtx);
1695   _mesa_enable_1_3_extensions(mesaCtx);
1696   _mesa_enable_1_4_extensions(mesaCtx);
1697   _mesa_enable_1_5_extensions(mesaCtx);
1698   _mesa_enable_2_0_extensions(mesaCtx);
1699#if SWTC
1700    if (c->Mesa_DXTn) {
1701       _mesa_enable_extension(c, "GL_EXT_texture_compression_s3tc");
1702       _mesa_enable_extension(c, "GL_S3_s3tc");
1703    }
1704    _mesa_enable_extension(c, "GL_3DFX_texture_compression_FXT1");
1705#endif
1706
1707   /* finish up xmesa context initializations */
1708   c->swapbytes = CHECK_BYTE_ORDER(v) ? GL_FALSE : GL_TRUE;
1709   c->xm_visual = v;
1710   c->xm_draw_buffer = NULL;   /* set later by XMesaMakeCurrent */
1711   c->xm_read_buffer = NULL;   /* set later by XMesaMakeCurrent */
1712   c->xm_buffer = NULL;   /* set later by XMesaMakeCurrent */
1713   c->display = v->display;
1714   c->pixelformat = v->dithered_pf;      /* Dithering is enabled by default */
1715
1716   /* Initialize the software rasterizer and helper modules.
1717    */
1718   if (!_swrast_CreateContext( mesaCtx ) ||
1719       !_ac_CreateContext( mesaCtx ) ||
1720       !_tnl_CreateContext( mesaCtx ) ||
1721       !_swsetup_CreateContext( mesaCtx )) {
1722      _mesa_free_context_data(&c->mesa);
1723      _mesa_free(c);
1724      return NULL;
1725   }
1726
1727   /* tnl setup */
1728   tnl = TNL_CONTEXT(mesaCtx);
1729   tnl->Driver.RunPipeline = _tnl_run_pipeline;
1730   /* swrast setup */
1731   xmesa_register_swrast_functions( mesaCtx );
1732   _swsetup_Wakeup(mesaCtx);
1733
1734   return c;
1735}
1736
1737
1738
1739void XMesaDestroyContext( XMesaContext c )
1740{
1741   GLcontext *mesaCtx = &c->mesa;
1742#ifdef FX
1743   if (c->xm_draw_buffer && c->xm_buffer->FXctx)
1744      fxMesaDestroyContext(c->xm_draw_buffer->FXctx);
1745#endif
1746   _swsetup_DestroyContext( mesaCtx );
1747   _swrast_DestroyContext( mesaCtx );
1748   _tnl_DestroyContext( mesaCtx );
1749   _ac_DestroyContext( mesaCtx );
1750   _mesa_free_context_data( mesaCtx );
1751   _mesa_free( c );
1752}
1753
1754
1755
1756/*
1757 * XXX this isn't a public function!  It's a hack for the 3Dfx driver.
1758 * Create a new XMesaBuffer from an X window.
1759 * Input:  v - the XMesaVisual
1760 *         w - the window
1761 *         c - the context
1762 * Return:  new XMesaBuffer or NULL if error
1763 */
1764XMesaBuffer
1765XMesaCreateWindowBuffer2(XMesaVisual v, XMesaWindow w, XMesaContext c)
1766{
1767#ifndef XFree86Server
1768   XWindowAttributes attr;
1769#endif
1770#ifdef FX
1771   char *fxEnvVar;
1772#endif
1773   int client = 0;
1774   XMesaBuffer b;
1775   XMesaColormap cmap;
1776
1777   assert(v);
1778   (void) c;
1779
1780   /* Check that window depth matches visual depth */
1781#ifdef XFree86Server
1782   client = CLIENT_ID(((XMesaDrawable)w)->id);
1783
1784   if (GET_VISUAL_DEPTH(v) != ((XMesaDrawable)w)->depth) {
1785      _mesa_warning(NULL, "XMesaCreateWindowBuffer: depth mismatch between visual (%d) and window (%d)!\n",
1786                    GET_VISUAL_DEPTH(v), ((XMesaDrawable) w)->depth);
1787      return NULL;
1788   }
1789#else
1790   XGetWindowAttributes( v->display, w, &attr );
1791
1792   if (GET_VISUAL_DEPTH(v) != attr.depth) {
1793      _mesa_warning(NULL, "XMesaCreateWindowBuffer: depth mismatch between visual (%d) and window (%d)!\n",
1794                    GET_VISUAL_DEPTH(v), attr.depth);
1795      return NULL;
1796   }
1797#endif
1798
1799   /* Find colormap */
1800#ifdef XFree86Server
1801   cmap = (ColormapPtr)LookupIDByType(wColormap(w), RT_COLORMAP);
1802#else
1803   if (attr.colormap) {
1804      cmap = attr.colormap;
1805   }
1806   else {
1807      _mesa_warning(NULL, "Window %u has no colormap!\n", (unsigned int) w);
1808      /* this is weird, a window w/out a colormap!? */
1809      /* OK, let's just allocate a new one and hope for the best */
1810      cmap = XCreateColormap(v->display, w, attr.visual, AllocNone);
1811   }
1812#endif
1813
1814   b = alloc_xmesa_buffer(v, WINDOW, cmap);
1815   if (!b) {
1816      return NULL;
1817   }
1818
1819   if (!initialize_visual_and_buffer( client, v, b, v->mesa_visual.rgbMode,
1820                                      (XMesaDrawable)w, cmap )) {
1821      free_xmesa_buffer(client, b);
1822      return NULL;
1823   }
1824
1825#ifdef FX
1826   fxEnvVar = _mesa_getenv("MESA_GLX_FX");
1827   if (fxEnvVar) {
1828     if (fxEnvVar[0]!='d') {
1829       int attribs[100];
1830       int numAttribs = 0;
1831       int hw;
1832       if (v->mesa_visual.depthBits > 0) {
1833	 attribs[numAttribs++] = FXMESA_DEPTH_SIZE;
1834	 attribs[numAttribs++] = v->mesa_visual.depthBits;
1835       }
1836       if (v->mesa_visual.doubleBufferMode) {
1837	 attribs[numAttribs++] = FXMESA_DOUBLEBUFFER;
1838       }
1839       if (v->mesa_visual.accumRedBits > 0) {
1840	 attribs[numAttribs++] = FXMESA_ACCUM_SIZE;
1841	 attribs[numAttribs++] = v->mesa_visual.accumRedBits;
1842       }
1843       if (v->mesa_visual.stencilBits > 0) {
1844         attribs[numAttribs++] = FXMESA_STENCIL_SIZE;
1845         attribs[numAttribs++] = v->mesa_visual.stencilBits;
1846       }
1847       if (v->mesa_visual.alphaBits > 0) {
1848         attribs[numAttribs++] = FXMESA_ALPHA_SIZE;
1849         attribs[numAttribs++] = v->mesa_visual.alphaBits;
1850       }
1851       if (1) {
1852         attribs[numAttribs++] = FXMESA_SHARE_CONTEXT;
1853         attribs[numAttribs++] = (int) &(c->mesa);
1854       }
1855       attribs[numAttribs++] = FXMESA_NONE;
1856
1857       /* [dBorca] we should take an envvar for `fxMesaSelectCurrentBoard'!!! */
1858       hw = fxMesaSelectCurrentBoard(0);
1859
1860       /* if these fail, there's a new bug somewhere */
1861       ASSERT(b->mesa_buffer.Width > 0);
1862       ASSERT(b->mesa_buffer.Height > 0);
1863
1864       if ((hw == GR_SSTTYPE_VOODOO) || (hw == GR_SSTTYPE_Voodoo2)) {
1865         b->FXctx = fxMesaCreateBestContext(0, b->mesa_buffer.Width,
1866                                            b->mesa_buffer.Height, attribs);
1867         if ((v->undithered_pf!=PF_Index) && (b->backimage)) {
1868	   b->FXisHackUsable = b->FXctx ? GL_TRUE : GL_FALSE;
1869	   if (b->FXctx && (fxEnvVar[0]=='w' || fxEnvVar[0]=='W')) {
1870	     b->FXwindowHack = GL_TRUE;
1871	     FX_grSstControl(GR_CONTROL_DEACTIVATE);
1872	   }
1873           else {
1874	     b->FXwindowHack = GL_FALSE;
1875	   }
1876         }
1877       }
1878       else {
1879         if (fxEnvVar[0]=='w' || fxEnvVar[0]=='W')
1880	   b->FXctx = fxMesaCreateContext(w, GR_RESOLUTION_NONE,
1881					  GR_REFRESH_75Hz, attribs);
1882         else
1883	   b->FXctx = fxMesaCreateBestContext(0, b->mesa_buffer.Width,
1884                                              b->mesa_buffer.Height, attribs);
1885         b->FXisHackUsable = GL_FALSE;
1886         b->FXwindowHack = GL_FALSE;
1887       }
1888       /*
1889       fprintf(stderr,
1890               "voodoo %d, wid %d height %d hack: usable %d active %d\n",
1891               hw, b->width, b->height, b->FXisHackUsable, b->FXwindowHack);
1892       */
1893     }
1894   }
1895   else {
1896      _mesa_warning(NULL, "WARNING: This Mesa Library includes the Glide driver but\n");
1897      _mesa_warning(NULL, "         you have not defined the MESA_GLX_FX env. var.\n");
1898      _mesa_warning(NULL, "         (check the README.3DFX file for more information).\n\n");
1899      _mesa_warning(NULL, "         you can disable this message with a 'export MESA_GLX_FX=disable'.\n");
1900   }
1901#endif
1902
1903   return b;
1904}
1905
1906
1907XMesaBuffer
1908XMesaCreateWindowBuffer(XMesaVisual v, XMesaWindow w)
1909{
1910   return XMesaCreateWindowBuffer2( v, w, NULL );
1911}
1912
1913
1914/**
1915 * Create a new XMesaBuffer from an X pixmap.
1916 *
1917 * \param v    the XMesaVisual
1918 * \param p    the pixmap
1919 * \param cmap the colormap, may be 0 if using a \c GLX_TRUE_COLOR or
1920 *             \c GLX_DIRECT_COLOR visual for the pixmap
1921 * \returns new XMesaBuffer or NULL if error
1922 */
1923XMesaBuffer
1924XMesaCreatePixmapBuffer(XMesaVisual v, XMesaPixmap p, XMesaColormap cmap)
1925{
1926   int client = 0;
1927   XMesaBuffer b;
1928
1929   assert(v);
1930
1931   b = alloc_xmesa_buffer(v, PIXMAP, cmap);
1932   if (!b) {
1933      return NULL;
1934   }
1935
1936#ifdef XFree86Server
1937   client = CLIENT_ID(((XMesaDrawable)p)->id);
1938#endif
1939
1940   if (!initialize_visual_and_buffer(client, v, b, v->mesa_visual.rgbMode,
1941				     (XMesaDrawable)p, cmap)) {
1942      free_xmesa_buffer(client, b);
1943      return NULL;
1944   }
1945
1946   return b;
1947}
1948
1949
1950
1951XMesaBuffer
1952XMesaCreatePBuffer(XMesaVisual v, XMesaColormap cmap,
1953                   unsigned int width, unsigned int height)
1954{
1955#ifdef XFree86Server
1956   return 0;
1957#else
1958   int client = 0;
1959   XMesaWindow root;
1960   XMesaDrawable drawable;  /* X Pixmap Drawable */
1961   XMesaBuffer b;
1962
1963   b = alloc_xmesa_buffer(v, PBUFFER, cmap);
1964   if (!b) {
1965      return NULL;
1966   }
1967
1968   /* allocate pixmap for front buffer */
1969   root = RootWindow( v->display, v->visinfo->screen );
1970   drawable = XCreatePixmap( v->display, root, width, height, v->visinfo->depth );
1971
1972   if (!initialize_visual_and_buffer(client, v, b, v->mesa_visual.rgbMode,
1973				     drawable, cmap)) {
1974      free_xmesa_buffer(client, b);
1975      return NULL;
1976   }
1977
1978   return b;
1979#endif
1980}
1981
1982
1983
1984/*
1985 * Deallocate an XMesaBuffer structure and all related info.
1986 */
1987void XMesaDestroyBuffer( XMesaBuffer b )
1988{
1989   int client = 0;
1990
1991#ifdef XFree86Server
1992   if (b->frontbuffer)
1993       client = CLIENT_ID(b->frontbuffer->id);
1994#endif
1995
1996   if (b->gc)  XMesaFreeGC( b->xm_visual->display, b->gc );
1997   if (b->cleargc)  XMesaFreeGC( b->xm_visual->display, b->cleargc );
1998   if (b->swapgc)  XMesaFreeGC( b->xm_visual->display, b->swapgc );
1999
2000   if (b->backimage) {
2001#if defined(USE_XSHM) && !defined(XFree86Server)
2002       if (b->shm) {
2003	   XShmDetach( b->xm_visual->display, &b->shminfo );
2004	   XDestroyImage( b->backimage );
2005	   shmdt( b->shminfo.shmaddr );
2006       }
2007       else
2008#endif
2009	   XMesaDestroyImage( b->backimage );
2010   }
2011   if (b->backpixmap) {
2012      XMesaFreePixmap( b->xm_visual->display, b->backpixmap );
2013      if (b->xm_visual->hpcr_clear_flag) {
2014	XMesaFreePixmap( b->xm_visual->display,
2015			 b->xm_visual->hpcr_clear_pixmap );
2016	XMesaDestroyImage( b->xm_visual->hpcr_clear_ximage );
2017      }
2018   }
2019   if (b->rowimage) {
2020      FREE( b->rowimage->data );
2021      b->rowimage->data = NULL;
2022      XMesaDestroyImage( b->rowimage );
2023   }
2024
2025   free_xmesa_buffer(client, b);
2026}
2027
2028
2029
2030/*
2031 * Bind buffer b to context c and make c the current rendering context.
2032 */
2033GLboolean XMesaMakeCurrent( XMesaContext c, XMesaBuffer b )
2034{
2035   return XMesaMakeCurrent2( c, b, b );
2036}
2037
2038
2039/*
2040 * Bind buffer b to context c and make c the current rendering context.
2041 */
2042GLboolean XMesaMakeCurrent2( XMesaContext c, XMesaBuffer drawBuffer,
2043                             XMesaBuffer readBuffer )
2044{
2045   if (c) {
2046      if (!drawBuffer || !readBuffer)
2047         return GL_FALSE;  /* must specify buffers! */
2048
2049#ifdef FX
2050      if (drawBuffer->FXctx) {
2051         fxMesaMakeCurrent(drawBuffer->FXctx);
2052
2053         c->xm_draw_buffer = drawBuffer;
2054         c->xm_read_buffer = readBuffer;
2055         c->xm_buffer = drawBuffer;
2056
2057         return GL_TRUE;
2058      }
2059#endif
2060      if (&(c->mesa) == _mesa_get_current_context()
2061          && c->xm_draw_buffer == drawBuffer
2062          && c->xm_read_buffer == readBuffer
2063          && c->xm_draw_buffer->wasCurrent) {
2064         /* same context and buffer, do nothing */
2065         return GL_TRUE;
2066      }
2067
2068      c->xm_draw_buffer = drawBuffer;
2069      c->xm_read_buffer = readBuffer;
2070      c->xm_buffer = drawBuffer;
2071
2072      _mesa_make_current2(&(c->mesa),
2073                          &drawBuffer->mesa_buffer,
2074                          &readBuffer->mesa_buffer);
2075
2076      if (c->xm_visual->mesa_visual.rgbMode) {
2077         /*
2078          * Must recompute and set these pixel values because colormap
2079          * can be different for different windows.
2080          */
2081         c->clearpixel = xmesa_color_to_pixel( c,
2082                                               c->clearcolor[0],
2083                                               c->clearcolor[1],
2084                                               c->clearcolor[2],
2085                                               c->clearcolor[3],
2086                                               c->xm_visual->undithered_pf);
2087         XMesaSetForeground(c->display, c->xm_draw_buffer->cleargc, c->clearpixel);
2088      }
2089
2090      /* Solution to Stephane Rehel's problem with glXReleaseBuffersMESA(): */
2091      c->xm_draw_buffer->wasCurrent = GL_TRUE;
2092   }
2093   else {
2094      /* Detach */
2095      _mesa_make_current2( NULL, NULL, NULL );
2096   }
2097   return GL_TRUE;
2098}
2099
2100
2101/*
2102 * Unbind the context c from its buffer.
2103 */
2104GLboolean XMesaUnbindContext( XMesaContext c )
2105{
2106   /* A no-op for XFree86 integration purposes */
2107   return GL_TRUE;
2108}
2109
2110
2111XMesaContext XMesaGetCurrentContext( void )
2112{
2113   GET_CURRENT_CONTEXT(ctx);
2114   if (ctx) {
2115      XMesaContext xmesa = XMESA_CONTEXT(ctx);
2116      return xmesa;
2117   }
2118   else {
2119      return 0;
2120   }
2121}
2122
2123
2124XMesaBuffer XMesaGetCurrentBuffer( void )
2125{
2126   GET_CURRENT_CONTEXT(ctx);
2127   if (ctx) {
2128      XMesaContext xmesa = XMESA_CONTEXT(ctx);
2129      return xmesa->xm_draw_buffer;
2130   }
2131   else {
2132      return 0;
2133   }
2134}
2135
2136
2137/* New in Mesa 3.1 */
2138XMesaBuffer XMesaGetCurrentReadBuffer( void )
2139{
2140   GET_CURRENT_CONTEXT(ctx);
2141   if (ctx) {
2142      XMesaContext xmesa = XMESA_CONTEXT(ctx);
2143      return xmesa->xm_read_buffer;
2144   }
2145   else {
2146      return 0;
2147   }
2148}
2149
2150
2151GLboolean XMesaForceCurrent(XMesaContext c)
2152{
2153   if (c) {
2154      if (&(c->mesa) != _mesa_get_current_context()) {
2155	 _mesa_make_current(&(c->mesa), &c->xm_draw_buffer->mesa_buffer);
2156      }
2157   }
2158   else {
2159      _mesa_make_current(NULL, NULL);
2160   }
2161   return GL_TRUE;
2162}
2163
2164
2165GLboolean XMesaLoseCurrent(XMesaContext c)
2166{
2167   (void) c;
2168   _mesa_make_current(NULL, NULL);
2169   return GL_TRUE;
2170}
2171
2172
2173/*
2174 * Switch 3Dfx support hack between window and full-screen mode.
2175 */
2176GLboolean XMesaSetFXmode( GLint mode )
2177{
2178#ifdef FX
2179   const char *fx = _mesa_getenv("MESA_GLX_FX");
2180   if (fx && fx[0] != 'd') {
2181      GET_CURRENT_CONTEXT(ctx);
2182      GrHwConfiguration hw;
2183      if (!FX_grSstQueryHardware(&hw)) {
2184         /*fprintf(stderr, "!grSstQueryHardware\n");*/
2185         return GL_FALSE;
2186      }
2187      if (hw.num_sst < 1) {
2188         /*fprintf(stderr, "hw.num_sst < 1\n");*/
2189         return GL_FALSE;
2190      }
2191      if (ctx) {
2192         /* [dBorca] Hack alert:
2193	  * oh, this is sooo wrong: ctx above is
2194	  * really an fxMesaContext, not an XMesaContext
2195	  */
2196         XMesaContext xmesa = XMESA_CONTEXT(ctx);
2197         if (mode == XMESA_FX_WINDOW) {
2198	    if (xmesa->xm_draw_buffer->FXisHackUsable) {
2199	       FX_grSstControl(GR_CONTROL_DEACTIVATE);
2200	       xmesa->xm_draw_buffer->FXwindowHack = GL_TRUE;
2201	       return GL_TRUE;
2202	    }
2203	 }
2204	 else if (mode == XMESA_FX_FULLSCREEN) {
2205	    FX_grSstControl(GR_CONTROL_ACTIVATE);
2206	    xmesa->xm_draw_buffer->FXwindowHack = GL_FALSE;
2207	    return GL_TRUE;
2208	 }
2209	 else {
2210	    /* Error: Bad mode value */
2211	 }
2212      }
2213   }
2214   /*fprintf(stderr, "fallthrough\n");*/
2215#else
2216   (void) mode;
2217#endif
2218   return GL_FALSE;
2219}
2220
2221
2222
2223#ifdef FX
2224/*
2225 * Read image from VooDoo frame buffer into X/Mesa's back XImage.
2226 */
2227static void FXgetImage( XMesaBuffer b )
2228{
2229   GET_CURRENT_CONTEXT(ctx);
2230   static unsigned short pixbuf[MAX_WIDTH];
2231   GLuint x, y;
2232   int xpos, ypos;
2233   XMesaWindow root;
2234   unsigned int bw, depth, width, height;
2235   XMesaContext xmesa = XMESA_CONTEXT(ctx);
2236
2237#ifdef XFree86Server
2238   x = b->frontbuffer->x;
2239   y = b->frontbuffer->y;
2240   width = b->frontbuffer->width;
2241   height = b->frontbuffer->height;
2242   depth = b->frontbuffer->depth;
2243#else
2244   XGetGeometry( b->xm_visual->display, b->frontbuffer,
2245                 &root, &xpos, &ypos, &width, &height, &bw, &depth);
2246#endif
2247   if (b->mesa_buffer.Width != width || b->mesa_buffer.Height != height) {
2248      b->mesa_buffer.Width = MIN2((int)width, b->FXctx->width);
2249      b->mesa_buffer.Height = MIN2((int)height, b->FXctx->height);
2250      if (b->mesa_buffer.Width & 1)
2251         b->mesa_buffer.Width--;  /* prevent odd width */
2252      xmesa_alloc_back_buffer( b );
2253   }
2254
2255   /* [dBorca] we're always in the right GR_COLORFORMAT... aren't we? */
2256   /* grLfbWriteColorFormat(GR_COLORFORMAT_ARGB); */
2257   if (b->xm_visual->undithered_pf==PF_5R6G5B) {
2258      /* Special case: 16bpp RGB */
2259      grLfbReadRegion( GR_BUFFER_FRONTBUFFER,       /* src buffer */
2260                       0, b->FXctx->height - b->mesa_buffer.Height,  /*pos*/
2261                       b->mesa_buffer.Width, b->mesa_buffer.Height,  /* size */
2262                       b->mesa_buffer.Width * sizeof(GLushort), /* stride */
2263                       b->backimage->data);         /* dest buffer */
2264   }
2265   else if (b->xm_visual->dithered_pf==PF_Dither
2266	    && GET_VISUAL_DEPTH(b->xm_visual)==8) {
2267      /* Special case: 8bpp RGB */
2268      for (y=0;y<b->mesa_buffer.Height;y++) {
2269         GLubyte *ptr = (GLubyte*) b->backimage->data
2270                        + b->backimage->bytes_per_line * y;
2271         XDITHER_SETUP(y);
2272
2273         /* read row from 3Dfx frame buffer */
2274         grLfbReadRegion( GR_BUFFER_FRONTBUFFER,
2275                          0, b->FXctx->height-(b->mesa_buffer.Height-y),
2276                          b->mesa_buffer.Width, 1,
2277                          0,
2278                          pixbuf );
2279
2280         /* write to XImage back buffer */
2281         for (x=0;x<b->mesa_buffer.Width;x++) {
2282            GLubyte r = (pixbuf[x] & 0xf800) >> 8;
2283            GLubyte g = (pixbuf[x] & 0x07e0) >> 3;
2284            GLubyte b = (pixbuf[x] & 0x001f) << 3;
2285            *ptr++ = XDITHER( x, r, g, b);
2286         }
2287      }
2288   }
2289   else {
2290      /* General case: slow! */
2291      for (y=0;y<b->mesa_buffer.Height;y++) {
2292         /* read row from 3Dfx frame buffer */
2293         grLfbReadRegion( GR_BUFFER_FRONTBUFFER,
2294                          0, b->FXctx->height-(b->mesa_buffer.Height-y),
2295                          b->mesa_buffer.Width, 1,
2296                          0,
2297                          pixbuf );
2298
2299         /* write to XImage back buffer */
2300         for (x=0;x<b->mesa_buffer.Width;x++) {
2301            XMesaPutPixel(b->backimage,x,y,
2302			  xmesa_color_to_pixel(xmesa,
2303					       (pixbuf[x] & 0xf800) >> 8,
2304					       (pixbuf[x] & 0x07e0) >> 3,
2305					       (pixbuf[x] & 0x001f) << 3,
2306					       0xff,
2307                                               b->xm_visual->undithered_pf));
2308         }
2309      }
2310   }
2311   /* grLfbWriteColorFormat(GR_COLORFORMAT_ABGR); */
2312}
2313#endif
2314
2315
2316/*
2317 * Copy the back buffer to the front buffer.  If there's no back buffer
2318 * this is a no-op.
2319 */
2320void XMesaSwapBuffers( XMesaBuffer b )
2321{
2322   GET_CURRENT_CONTEXT(ctx);
2323
2324   /* If we're swapping the buffer associated with the current context
2325    * we have to flush any pending rendering commands first.
2326    */
2327   if (ctx && ctx->DrawBuffer == &(b->mesa_buffer))
2328      _mesa_notifySwapBuffers(ctx);
2329
2330   if (b->db_state) {
2331#ifdef FX
2332      if (b->FXctx) {
2333         fxMesaSwapBuffers();
2334
2335         if (b->FXwindowHack)
2336            FXgetImage(b);
2337         else
2338            return;
2339      }
2340#endif
2341     if (b->backimage) {
2342	 /* Copy Ximage from host's memory to server's window */
2343#if defined(USE_XSHM) && !defined(XFree86Server)
2344	 if (b->shm) {
2345            /*_glthread_LOCK_MUTEX(_xmesa_lock);*/
2346	    XShmPutImage( b->xm_visual->display, b->frontbuffer,
2347			  b->swapgc,
2348			  b->backimage, 0, 0,
2349			  0, 0, b->mesa_buffer.Width, b->mesa_buffer.Height,
2350                          False );
2351            /*_glthread_UNLOCK_MUTEX(_xmesa_lock);*/
2352	 }
2353	 else
2354#endif
2355         {
2356            /*_glthread_LOCK_MUTEX(_xmesa_lock);*/
2357            XMesaPutImage( b->xm_visual->display, b->frontbuffer,
2358			   b->swapgc,
2359			   b->backimage, 0, 0,
2360			   0, 0, b->mesa_buffer.Width, b->mesa_buffer.Height );
2361            /*_glthread_UNLOCK_MUTEX(_xmesa_lock);*/
2362         }
2363      }
2364      else {
2365	 /* Copy pixmap to window on server */
2366         /*_glthread_LOCK_MUTEX(_xmesa_lock);*/
2367	 XMesaCopyArea( b->xm_visual->display,
2368			b->backpixmap,   /* source drawable */
2369			b->frontbuffer,  /* dest. drawable */
2370			b->swapgc,
2371			0, 0, b->mesa_buffer.Width, b->mesa_buffer.Height,
2372			0, 0                 /* dest region */
2373		      );
2374         /*_glthread_UNLOCK_MUTEX(_xmesa_lock);*/
2375      }
2376   }
2377#if !defined(XFree86Server)
2378   XSync( b->xm_visual->display, False );
2379#endif
2380}
2381
2382
2383
2384/*
2385 * Copy sub-region of back buffer to front buffer
2386 */
2387void XMesaCopySubBuffer( XMesaBuffer b, int x, int y, int width, int height )
2388{
2389   GET_CURRENT_CONTEXT(ctx);
2390
2391   /* If we're swapping the buffer associated with the current context
2392    * we have to flush any pending rendering commands first.
2393    */
2394   if (ctx && ctx->DrawBuffer == &(b->mesa_buffer))
2395      _mesa_notifySwapBuffers(ctx);
2396
2397   if (b->db_state) {
2398      int yTop = b->mesa_buffer.Height - y - height;
2399#ifdef FX
2400      if (b->FXctx) {
2401         fxMesaSwapBuffers();
2402         if (b->FXwindowHack)
2403            FXgetImage(b);
2404         else
2405            return;
2406      }
2407#endif
2408      if (b->backimage) {
2409         /* Copy Ximage from host's memory to server's window */
2410#if defined(USE_XSHM) && !defined(XFree86Server)
2411         if (b->shm) {
2412            /* XXX assuming width and height aren't too large! */
2413            XShmPutImage( b->xm_visual->display, b->frontbuffer,
2414                          b->swapgc,
2415                          b->backimage, x, yTop,
2416                          x, yTop, width, height, False );
2417            /* wait for finished event??? */
2418         }
2419         else
2420#endif
2421         {
2422            /* XXX assuming width and height aren't too large! */
2423            XMesaPutImage( b->xm_visual->display, b->frontbuffer,
2424			   b->swapgc,
2425			   b->backimage, x, yTop,
2426			   x, yTop, width, height );
2427         }
2428      }
2429      else {
2430         /* Copy pixmap to window on server */
2431         XMesaCopyArea( b->xm_visual->display,
2432			b->backpixmap,           /* source drawable */
2433			b->frontbuffer,          /* dest. drawable */
2434			b->swapgc,
2435			x, yTop, width, height,  /* source region */
2436			x, yTop                  /* dest region */
2437                      );
2438      }
2439   }
2440}
2441
2442
2443/*
2444 * Return a pointer to the XMesa backbuffer Pixmap or XImage.  This function
2445 * is a way to get "under the hood" of X/Mesa so one can manipulate the
2446 * back buffer directly.
2447 * Output:  pixmap - pointer to back buffer's Pixmap, or 0
2448 *          ximage - pointer to back buffer's XImage, or NULL
2449 * Return:  GL_TRUE = context is double buffered
2450 *          GL_FALSE = context is single buffered
2451 */
2452GLboolean XMesaGetBackBuffer( XMesaBuffer b,
2453                              XMesaPixmap *pixmap,
2454                              XMesaImage **ximage )
2455{
2456   if (b->db_state) {
2457      if (pixmap)  *pixmap = b->backpixmap;
2458      if (ximage)  *ximage = b->backimage;
2459      return GL_TRUE;
2460   }
2461   else {
2462      *pixmap = 0;
2463      *ximage = NULL;
2464      return GL_FALSE;
2465   }
2466}
2467
2468
2469/*
2470 * Return the depth buffer associated with an XMesaBuffer.
2471 * Input:  b - the XMesa buffer handle
2472 * Output:  width, height - size of buffer in pixels
2473 *          bytesPerValue - bytes per depth value (2 or 4)
2474 *          buffer - pointer to depth buffer values
2475 * Return:  GL_TRUE or GL_FALSE to indicate success or failure.
2476 */
2477GLboolean XMesaGetDepthBuffer( XMesaBuffer b, GLint *width, GLint *height,
2478                               GLint *bytesPerValue, void **buffer )
2479{
2480   if (!b->mesa_buffer.DepthBuffer) {
2481      *width = 0;
2482      *height = 0;
2483      *bytesPerValue = 0;
2484      *buffer = 0;
2485      return GL_FALSE;
2486   }
2487   else {
2488      *width = b->mesa_buffer.Width;
2489      *height = b->mesa_buffer.Height;
2490      *bytesPerValue = b->mesa_buffer.Visual.depthBits <= 16
2491         ? sizeof(GLushort) : sizeof(GLuint);
2492      *buffer = b->mesa_buffer.DepthBuffer;
2493      return GL_TRUE;
2494   }
2495}
2496
2497
2498void XMesaFlush( XMesaContext c )
2499{
2500   if (c && c->xm_visual) {
2501#ifdef XFree86Server
2502      /* NOT_NEEDED */
2503#else
2504      XSync( c->xm_visual->display, False );
2505#endif
2506   }
2507}
2508
2509
2510
2511const char *XMesaGetString( XMesaContext c, int name )
2512{
2513   (void) c;
2514   if (name==XMESA_VERSION) {
2515      return "5.0";
2516   }
2517   else if (name==XMESA_EXTENSIONS) {
2518      return "";
2519   }
2520   else {
2521      return NULL;
2522   }
2523}
2524
2525
2526
2527XMesaBuffer XMesaFindBuffer( XMesaDisplay *dpy, XMesaDrawable d )
2528{
2529   XMesaBuffer b;
2530   for (b=XMesaBufferList; b; b=b->Next) {
2531      if (b->frontbuffer==d && b->display==dpy) {
2532         return b;
2533      }
2534   }
2535   return NULL;
2536}
2537
2538
2539
2540/*
2541 * Look for XMesaBuffers whose X window has been destroyed.
2542 * Deallocate any such XMesaBuffers.
2543 */
2544void XMesaGarbageCollect( void )
2545{
2546   XMesaBuffer b, next;
2547   for (b=XMesaBufferList; b; b=next) {
2548      next = b->Next;
2549      if (b->display && b->frontbuffer && b->type == WINDOW) {
2550#ifdef XFree86Server
2551	 /* NOT_NEEDED */
2552#else
2553         XSync(b->display, False);
2554         if (!window_exists( b->display, b->frontbuffer )) {
2555            /* found a dead window, free the ancillary info */
2556            XMesaDestroyBuffer( b );
2557         }
2558#endif
2559      }
2560   }
2561}
2562
2563
2564void XMesaReset( void )
2565{
2566    while (XMesaBufferList)
2567	XMesaDestroyBuffer(XMesaBufferList);
2568
2569    XMesaBufferList = NULL;
2570}
2571
2572
2573unsigned long XMesaDitherColor( XMesaContext xmesa, GLint x, GLint y,
2574                                GLfloat red, GLfloat green,
2575                                GLfloat blue, GLfloat alpha )
2576{
2577   GLint r = (GLint) (red   * 255.0F);
2578   GLint g = (GLint) (green * 255.0F);
2579   GLint b = (GLint) (blue  * 255.0F);
2580   GLint a = (GLint) (alpha * 255.0F);
2581
2582   switch (xmesa->pixelformat) {
2583      case PF_Index:
2584         return 0;
2585      case PF_Truecolor:
2586         {
2587            unsigned long p;
2588            PACK_TRUECOLOR( p, r, g, b );
2589            return p;
2590         }
2591      case PF_8A8B8G8R:
2592         return PACK_8A8B8G8R( r, g, b, a );
2593      case PF_8A8R8G8B:
2594         return PACK_8A8R8G8B( r, g, b, a );
2595      case PF_8R8G8B:
2596         return PACK_8R8G8B( r, g, b );
2597      case PF_5R6G5B:
2598         return PACK_5R6G5B( r, g, b );
2599      case PF_Dither:
2600         {
2601            DITHER_SETUP;
2602            return DITHER( x, y, r, g, b );
2603         }
2604      case PF_1Bit:
2605         /* 382 = (3*255)/2 */
2606         return ((r+g+b) > 382) ^ xmesa->xm_visual->bitFlip;
2607      case PF_HPCR:
2608         return DITHER_HPCR(x, y, r, g, b);
2609      case PF_Lookup:
2610         {
2611            LOOKUP_SETUP;
2612            return LOOKUP( r, g, b );
2613         }
2614      case PF_Grayscale:
2615         return GRAY_RGB( r, g, b );
2616      case PF_Dither_5R6G5B:
2617         /* fall through */
2618      case PF_Dither_True:
2619         {
2620            unsigned long p;
2621            PACK_TRUEDITHER(p, x, y, r, g, b);
2622            return p;
2623         }
2624      default:
2625         _mesa_problem(NULL, "Bad pixel format in XMesaDitherColor");
2626   }
2627   return 0;
2628}
2629
2630
2631/*
2632 * This is typically called when the window size changes and we need
2633 * to reallocate the buffer's back/depth/stencil/accum buffers.
2634 */
2635void XMesaResizeBuffers( XMesaBuffer b )
2636{
2637   xmesa_resize_buffers( &(b->mesa_buffer) );
2638
2639}
2640
2641