1/*
2 * Mesa 3-D graphics library
3 * Version:  7.9
4 *
5 * Copyright (C) 2010 LunarG Inc.
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 OR
18 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
20 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
21 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
22 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
23 * DEALINGS IN THE SOFTWARE.
24 *
25 * Authors:
26 *    Chia-I Wu <olv@lunarg.com>
27 */
28
29#include "main/mtypes.h"
30#include "main/context.h"
31#include "main/mfeatures.h"
32#include "main/texobj.h"
33#include "main/teximage.h"
34#include "main/texstate.h"
35#include "main/framebuffer.h"
36#include "main/fbobject.h"
37#include "main/renderbuffer.h"
38#include "main/version.h"
39#include "st_texture.h"
40
41#include "st_context.h"
42#include "st_format.h"
43#include "st_cb_fbo.h"
44#include "st_cb_flush.h"
45#include "st_manager.h"
46
47#include "state_tracker/st_gl_api.h"
48
49#include "pipe/p_context.h"
50#include "pipe/p_screen.h"
51#include "util/u_format.h"
52#include "util/u_pointer.h"
53#include "util/u_inlines.h"
54#include "util/u_atomic.h"
55#include "util/u_surface.h"
56
57/**
58 * Cast wrapper to convert a struct gl_framebuffer to an st_framebuffer.
59 * Return NULL if the struct gl_framebuffer is a user-created framebuffer.
60 * We'll only return non-null for window system framebuffers.
61 * Note that this function may fail.
62 */
63static INLINE struct st_framebuffer *
64st_ws_framebuffer(struct gl_framebuffer *fb)
65{
66   /* FBO cannot be casted.  See st_new_framebuffer */
67   if (fb && _mesa_is_winsys_fbo(fb))
68      return (struct st_framebuffer *) fb;
69   return NULL;
70}
71
72/**
73 * Map an attachment to a buffer index.
74 */
75static INLINE gl_buffer_index
76attachment_to_buffer_index(enum st_attachment_type statt)
77{
78   gl_buffer_index index;
79
80   switch (statt) {
81   case ST_ATTACHMENT_FRONT_LEFT:
82      index = BUFFER_FRONT_LEFT;
83      break;
84   case ST_ATTACHMENT_BACK_LEFT:
85      index = BUFFER_BACK_LEFT;
86      break;
87   case ST_ATTACHMENT_FRONT_RIGHT:
88      index = BUFFER_FRONT_RIGHT;
89      break;
90   case ST_ATTACHMENT_BACK_RIGHT:
91      index = BUFFER_BACK_RIGHT;
92      break;
93   case ST_ATTACHMENT_DEPTH_STENCIL:
94      index = BUFFER_DEPTH;
95      break;
96   case ST_ATTACHMENT_ACCUM:
97      index = BUFFER_ACCUM;
98      break;
99   case ST_ATTACHMENT_SAMPLE:
100   default:
101      index = BUFFER_COUNT;
102      break;
103   }
104
105   return index;
106}
107
108/**
109 * Map a buffer index to an attachment.
110 */
111static INLINE enum st_attachment_type
112buffer_index_to_attachment(gl_buffer_index index)
113{
114   enum st_attachment_type statt;
115
116   switch (index) {
117   case BUFFER_FRONT_LEFT:
118      statt = ST_ATTACHMENT_FRONT_LEFT;
119      break;
120   case BUFFER_BACK_LEFT:
121      statt = ST_ATTACHMENT_BACK_LEFT;
122      break;
123   case BUFFER_FRONT_RIGHT:
124      statt = ST_ATTACHMENT_FRONT_RIGHT;
125      break;
126   case BUFFER_BACK_RIGHT:
127      statt = ST_ATTACHMENT_BACK_RIGHT;
128      break;
129   case BUFFER_DEPTH:
130      statt = ST_ATTACHMENT_DEPTH_STENCIL;
131      break;
132   case BUFFER_ACCUM:
133      statt = ST_ATTACHMENT_ACCUM;
134      break;
135   default:
136      statt = ST_ATTACHMENT_INVALID;
137      break;
138   }
139
140   return statt;
141}
142
143/**
144 * Make sure a context picks up the latest cached state of the
145 * drawables it binds to.
146 */
147static void
148st_context_validate(struct st_context *st,
149                    struct st_framebuffer *stdraw,
150                    struct st_framebuffer *stread)
151{
152    if (stdraw && stdraw->stamp != st->draw_stamp) {
153       st->dirty.st |= ST_NEW_FRAMEBUFFER;
154       _mesa_resize_framebuffer(st->ctx, &stdraw->Base,
155                                stdraw->Base.Width,
156                                stdraw->Base.Height);
157       st->draw_stamp = stdraw->stamp;
158    }
159
160    if (stread && stread->stamp != st->read_stamp) {
161       if (stread != stdraw) {
162          st->dirty.st |= ST_NEW_FRAMEBUFFER;
163          _mesa_resize_framebuffer(st->ctx, &stread->Base,
164                                   stread->Base.Width,
165                                   stread->Base.Height);
166       }
167       st->read_stamp = stread->stamp;
168    }
169}
170
171/**
172 * Validate a framebuffer to make sure up-to-date pipe_textures are used.
173 * The context we need to pass in is s dummy context needed only to be
174 * able to get a pipe context to create pipe surfaces, and to have a
175 * context to call _mesa_resize_framebuffer():
176 * (That should probably be rethought, since those surfaces become
177 * drawable state, not context state, and can be freed by another pipe
178 * context).
179 */
180static void
181st_framebuffer_validate(struct st_framebuffer *stfb,
182                        struct st_context *st)
183{
184   struct pipe_resource *textures[ST_ATTACHMENT_COUNT];
185   uint width, height;
186   unsigned i;
187   boolean changed = FALSE;
188   int32_t new_stamp = p_atomic_read(&stfb->iface->stamp);
189
190   if (stfb->iface_stamp == new_stamp)
191      return;
192
193   /* validate the fb */
194   do {
195      if (!stfb->iface->validate(stfb->iface, stfb->statts,
196				 stfb->num_statts, textures))
197	 return;
198
199      stfb->iface_stamp = new_stamp;
200      new_stamp = p_atomic_read(&stfb->iface->stamp);
201   } while(stfb->iface_stamp != new_stamp);
202
203   width = stfb->Base.Width;
204   height = stfb->Base.Height;
205
206   for (i = 0; i < stfb->num_statts; i++) {
207      struct st_renderbuffer *strb;
208      struct pipe_surface *ps, surf_tmpl;
209      gl_buffer_index idx;
210
211      if (!textures[i])
212         continue;
213
214      idx = attachment_to_buffer_index(stfb->statts[i]);
215      if (idx >= BUFFER_COUNT) {
216         pipe_resource_reference(&textures[i], NULL);
217         continue;
218      }
219
220      strb = st_renderbuffer(stfb->Base.Attachment[idx].Renderbuffer);
221      assert(strb);
222      if (strb->texture == textures[i]) {
223         pipe_resource_reference(&textures[i], NULL);
224         continue;
225      }
226
227      u_surface_default_template(&surf_tmpl, textures[i],
228                                 PIPE_BIND_RENDER_TARGET);
229      ps = st->pipe->create_surface(st->pipe, textures[i], &surf_tmpl);
230      if (ps) {
231         pipe_surface_reference(&strb->surface, ps);
232         pipe_resource_reference(&strb->texture, ps->texture);
233         /* ownership transfered */
234         pipe_surface_reference(&ps, NULL);
235
236         changed = TRUE;
237
238         strb->Base.Width = strb->surface->width;
239         strb->Base.Height = strb->surface->height;
240
241         width = strb->Base.Width;
242         height = strb->Base.Height;
243      }
244
245      pipe_resource_reference(&textures[i], NULL);
246   }
247
248   if (changed) {
249      ++stfb->stamp;
250      _mesa_resize_framebuffer(st->ctx, &stfb->Base, width, height);
251   }
252}
253
254/**
255 * Update the attachments to validate by looping the existing renderbuffers.
256 */
257static void
258st_framebuffer_update_attachments(struct st_framebuffer *stfb)
259{
260   gl_buffer_index idx;
261
262   stfb->num_statts = 0;
263   for (idx = 0; idx < BUFFER_COUNT; idx++) {
264      struct st_renderbuffer *strb;
265      enum st_attachment_type statt;
266
267      strb = st_renderbuffer(stfb->Base.Attachment[idx].Renderbuffer);
268      if (!strb || strb->software)
269         continue;
270
271      statt = buffer_index_to_attachment(idx);
272      if (statt != ST_ATTACHMENT_INVALID &&
273          st_visual_have_buffers(stfb->iface->visual, 1 << statt))
274         stfb->statts[stfb->num_statts++] = statt;
275   }
276   stfb->stamp++;
277}
278
279/**
280 * Add a renderbuffer to the framebuffer.
281 */
282static boolean
283st_framebuffer_add_renderbuffer(struct st_framebuffer *stfb,
284                                gl_buffer_index idx)
285{
286   struct gl_renderbuffer *rb;
287   enum pipe_format format;
288   int samples;
289   boolean sw;
290
291   if (!stfb->iface)
292      return FALSE;
293
294   /* do not distinguish depth/stencil buffers */
295   if (idx == BUFFER_STENCIL)
296      idx = BUFFER_DEPTH;
297
298   switch (idx) {
299   case BUFFER_DEPTH:
300      format = stfb->iface->visual->depth_stencil_format;
301      sw = FALSE;
302      break;
303   case BUFFER_ACCUM:
304      format = stfb->iface->visual->accum_format;
305      sw = TRUE;
306      break;
307   default:
308      format = stfb->iface->visual->color_format;
309      sw = FALSE;
310      break;
311   }
312
313   if (format == PIPE_FORMAT_NONE)
314      return FALSE;
315
316   samples = stfb->iface->visual->samples;
317   if (!samples)
318      samples = st_get_msaa();
319
320   rb = st_new_renderbuffer_fb(format, samples, sw);
321   if (!rb)
322      return FALSE;
323
324   if (idx != BUFFER_DEPTH) {
325      _mesa_add_renderbuffer(&stfb->Base, idx, rb);
326   }
327   else {
328      if (util_format_get_component_bits(format, UTIL_FORMAT_COLORSPACE_ZS, 0))
329         _mesa_add_renderbuffer(&stfb->Base, BUFFER_DEPTH, rb);
330      if (util_format_get_component_bits(format, UTIL_FORMAT_COLORSPACE_ZS, 1))
331         _mesa_add_renderbuffer(&stfb->Base, BUFFER_STENCIL, rb);
332   }
333
334   return TRUE;
335}
336
337/**
338 * Intialize a struct gl_config from a visual.
339 */
340static void
341st_visual_to_context_mode(const struct st_visual *visual,
342                          struct gl_config *mode)
343{
344   memset(mode, 0, sizeof(*mode));
345
346   if (st_visual_have_buffers(visual, ST_ATTACHMENT_BACK_LEFT_MASK))
347      mode->doubleBufferMode = GL_TRUE;
348   if (st_visual_have_buffers(visual,
349            ST_ATTACHMENT_FRONT_RIGHT_MASK | ST_ATTACHMENT_BACK_RIGHT_MASK))
350      mode->stereoMode = GL_TRUE;
351
352   if (visual->color_format != PIPE_FORMAT_NONE) {
353      mode->rgbMode = GL_TRUE;
354
355      mode->redBits =
356         util_format_get_component_bits(visual->color_format,
357               UTIL_FORMAT_COLORSPACE_RGB, 0);
358      mode->greenBits =
359         util_format_get_component_bits(visual->color_format,
360               UTIL_FORMAT_COLORSPACE_RGB, 1);
361      mode->blueBits =
362         util_format_get_component_bits(visual->color_format,
363               UTIL_FORMAT_COLORSPACE_RGB, 2);
364      mode->alphaBits =
365         util_format_get_component_bits(visual->color_format,
366               UTIL_FORMAT_COLORSPACE_RGB, 3);
367
368      mode->rgbBits = mode->redBits +
369         mode->greenBits + mode->blueBits + mode->alphaBits;
370   }
371
372   if (visual->depth_stencil_format != PIPE_FORMAT_NONE) {
373      mode->depthBits =
374         util_format_get_component_bits(visual->depth_stencil_format,
375               UTIL_FORMAT_COLORSPACE_ZS, 0);
376      mode->stencilBits =
377         util_format_get_component_bits(visual->depth_stencil_format,
378               UTIL_FORMAT_COLORSPACE_ZS, 1);
379
380      mode->haveDepthBuffer = mode->depthBits > 0;
381      mode->haveStencilBuffer = mode->stencilBits > 0;
382   }
383
384   if (visual->accum_format != PIPE_FORMAT_NONE) {
385      mode->haveAccumBuffer = GL_TRUE;
386
387      mode->accumRedBits =
388         util_format_get_component_bits(visual->accum_format,
389               UTIL_FORMAT_COLORSPACE_RGB, 0);
390      mode->accumGreenBits =
391         util_format_get_component_bits(visual->accum_format,
392               UTIL_FORMAT_COLORSPACE_RGB, 1);
393      mode->accumBlueBits =
394         util_format_get_component_bits(visual->accum_format,
395               UTIL_FORMAT_COLORSPACE_RGB, 2);
396      mode->accumAlphaBits =
397         util_format_get_component_bits(visual->accum_format,
398               UTIL_FORMAT_COLORSPACE_RGB, 3);
399   }
400
401   if (visual->samples) {
402      mode->sampleBuffers = 1;
403      mode->samples = visual->samples;
404   }
405}
406
407/**
408 * Create a framebuffer from a manager interface.
409 */
410static struct st_framebuffer *
411st_framebuffer_create(struct st_framebuffer_iface *stfbi)
412{
413   struct st_framebuffer *stfb;
414   struct gl_config mode;
415   gl_buffer_index idx;
416
417   if (!stfbi)
418      return NULL;
419
420   stfb = CALLOC_STRUCT(st_framebuffer);
421   if (!stfb)
422      return NULL;
423
424   st_visual_to_context_mode(stfbi->visual, &mode);
425   _mesa_initialize_window_framebuffer(&stfb->Base, &mode);
426
427   stfb->iface = stfbi;
428   stfb->iface_stamp = p_atomic_read(&stfbi->stamp) - 1;
429
430   /* add the color buffer */
431   idx = stfb->Base._ColorDrawBufferIndexes[0];
432   if (!st_framebuffer_add_renderbuffer(stfb, idx)) {
433      FREE(stfb);
434      return NULL;
435   }
436
437   st_framebuffer_add_renderbuffer(stfb, BUFFER_DEPTH);
438   st_framebuffer_add_renderbuffer(stfb, BUFFER_ACCUM);
439
440   stfb->stamp = 0;
441   st_framebuffer_update_attachments(stfb);
442
443   stfb->Base.Initialized = GL_TRUE;
444
445   return stfb;
446}
447
448/**
449 * Reference a framebuffer.
450 */
451static void
452st_framebuffer_reference(struct st_framebuffer **ptr,
453                         struct st_framebuffer *stfb)
454{
455   struct gl_framebuffer *fb = &stfb->Base;
456   _mesa_reference_framebuffer((struct gl_framebuffer **) ptr, fb);
457}
458
459static void
460st_context_flush(struct st_context_iface *stctxi, unsigned flags,
461                 struct pipe_fence_handle **fence)
462{
463   struct st_context *st = (struct st_context *) stctxi;
464   st_flush(st, fence);
465   if (flags & ST_FLUSH_FRONT)
466      st_manager_flush_frontbuffer(st);
467}
468
469static boolean
470st_context_teximage(struct st_context_iface *stctxi,
471                    enum st_texture_type tex_type,
472                    int level, enum pipe_format internal_format,
473                    struct pipe_resource *tex, boolean mipmap)
474{
475   struct st_context *st = (struct st_context *) stctxi;
476   struct gl_context *ctx = st->ctx;
477   struct gl_texture_unit *texUnit = _mesa_get_current_tex_unit(ctx);
478   struct gl_texture_object *texObj;
479   struct gl_texture_image *texImage;
480   struct st_texture_object *stObj;
481   struct st_texture_image *stImage;
482   GLenum internalFormat;
483   GLuint width, height, depth;
484   GLenum target;
485
486   switch (tex_type) {
487   case ST_TEXTURE_1D:
488      target = GL_TEXTURE_1D;
489      break;
490   case ST_TEXTURE_2D:
491      target = GL_TEXTURE_2D;
492      break;
493   case ST_TEXTURE_3D:
494      target = GL_TEXTURE_3D;
495      break;
496   case ST_TEXTURE_RECT:
497      target = GL_TEXTURE_RECTANGLE_ARB;
498      break;
499   default:
500      return FALSE;
501   }
502
503   texObj = _mesa_select_tex_object(ctx, texUnit, target);
504   _mesa_lock_texture(ctx, texObj);
505
506   stObj = st_texture_object(texObj);
507   /* switch to surface based */
508   if (!stObj->surface_based) {
509      _mesa_clear_texture_object(ctx, texObj);
510      stObj->surface_based = GL_TRUE;
511   }
512
513   texImage = _mesa_get_tex_image(ctx, texObj, target, level);
514   stImage = st_texture_image(texImage);
515   if (tex) {
516      gl_format texFormat;
517
518      /*
519       * XXX When internal_format and tex->format differ, st_finalize_texture
520       * needs to allocate a new texture with internal_format and copy the
521       * texture here into the new one.  It will result in surface_copy being
522       * called on surfaces whose formats differ.
523       *
524       * To avoid that, internal_format is (wrongly) ignored here.  A sane fix
525       * is to use a sampler view.
526       */
527      if (!st_sampler_compat_formats(tex->format, internal_format))
528	 internal_format = tex->format;
529
530      if (util_format_get_component_bits(internal_format,
531               UTIL_FORMAT_COLORSPACE_RGB, 3) > 0)
532         internalFormat = GL_RGBA;
533      else
534         internalFormat = GL_RGB;
535
536      texFormat = st_ChooseTextureFormat(ctx, target, internalFormat,
537                                         GL_BGRA, GL_UNSIGNED_BYTE);
538
539      _mesa_init_teximage_fields(ctx, texImage,
540                                 tex->width0, tex->height0, 1, 0,
541                                 internalFormat, texFormat);
542
543      width = tex->width0;
544      height = tex->height0;
545      depth = tex->depth0;
546
547      /* grow the image size until we hit level = 0 */
548      while (level > 0) {
549         if (width != 1)
550            width <<= 1;
551         if (height != 1)
552            height <<= 1;
553         if (depth != 1)
554            depth <<= 1;
555         level--;
556      }
557   }
558   else {
559      _mesa_clear_texture_image(ctx, texImage);
560      width = height = depth = 0;
561   }
562
563   pipe_resource_reference(&stImage->pt, tex);
564   stObj->width0 = width;
565   stObj->height0 = height;
566   stObj->depth0 = depth;
567
568   _mesa_dirty_texobj(ctx, texObj, GL_TRUE);
569   _mesa_unlock_texture(ctx, texObj);
570
571   return TRUE;
572}
573
574static void
575st_context_copy(struct st_context_iface *stctxi,
576                struct st_context_iface *stsrci, unsigned mask)
577{
578   struct st_context *st = (struct st_context *) stctxi;
579   struct st_context *src = (struct st_context *) stsrci;
580
581   _mesa_copy_context(src->ctx, st->ctx, mask);
582}
583
584static boolean
585st_context_share(struct st_context_iface *stctxi,
586                 struct st_context_iface *stsrci)
587{
588   struct st_context *st = (struct st_context *) stctxi;
589   struct st_context *src = (struct st_context *) stsrci;
590
591   return _mesa_share_state(st->ctx, src->ctx);
592}
593
594static void
595st_context_destroy(struct st_context_iface *stctxi)
596{
597   struct st_context *st = (struct st_context *) stctxi;
598   st_destroy_context(st);
599}
600
601static struct st_context_iface *
602st_api_create_context(struct st_api *stapi, struct st_manager *smapi,
603                      const struct st_context_attribs *attribs,
604                      enum st_context_error *error,
605                      struct st_context_iface *shared_stctxi)
606{
607   struct st_context *shared_ctx = (struct st_context *) shared_stctxi;
608   struct st_context *st;
609   struct pipe_context *pipe;
610   struct gl_config mode;
611   gl_api api;
612
613   if (!(stapi->profile_mask & (1 << attribs->profile)))
614      return NULL;
615
616   switch (attribs->profile) {
617   case ST_PROFILE_DEFAULT:
618      api = API_OPENGL;
619      break;
620   case ST_PROFILE_OPENGL_ES1:
621      api = API_OPENGLES;
622      break;
623   case ST_PROFILE_OPENGL_ES2:
624      api = API_OPENGLES2;
625      break;
626   case ST_PROFILE_OPENGL_CORE:
627   default:
628      *error = ST_CONTEXT_ERROR_BAD_API;
629      return NULL;
630      break;
631   }
632
633   pipe = smapi->screen->context_create(smapi->screen, NULL);
634   if (!pipe) {
635      *error = ST_CONTEXT_ERROR_NO_MEMORY;
636      return NULL;
637   }
638
639   st_visual_to_context_mode(&attribs->visual, &mode);
640   st = st_create_context(api, pipe, &mode, shared_ctx, &attribs->options);
641   if (!st) {
642      *error = ST_CONTEXT_ERROR_NO_MEMORY;
643      pipe->destroy(pipe);
644      return NULL;
645   }
646
647   /* need to perform version check */
648   if (attribs->major > 1 || attribs->minor > 0) {
649      _mesa_compute_version(st->ctx);
650
651      /* Is the actual version less than the requested version?  Mesa can't
652       * yet enforce the added restrictions of a forward-looking context, so
653       * fail that too.
654       */
655      if (st->ctx->Version < attribs->major * 10 + attribs->minor
656	  || (attribs->flags & ~ST_CONTEXT_FLAG_DEBUG) != 0) {
657	 *error = ST_CONTEXT_ERROR_BAD_VERSION;
658         st_destroy_context(st);
659         return NULL;
660      }
661   }
662
663   st->invalidate_on_gl_viewport =
664      smapi->get_param(smapi, ST_MANAGER_BROKEN_INVALIDATE);
665
666   st->iface.destroy = st_context_destroy;
667   st->iface.flush = st_context_flush;
668   st->iface.teximage = st_context_teximage;
669   st->iface.copy = st_context_copy;
670   st->iface.share = st_context_share;
671   st->iface.st_context_private = (void *) smapi;
672
673   *error = ST_CONTEXT_SUCCESS;
674   return &st->iface;
675}
676
677static struct st_context_iface *
678st_api_get_current(struct st_api *stapi)
679{
680   GET_CURRENT_CONTEXT(ctx);
681   struct st_context *st = (ctx) ? ctx->st : NULL;
682
683   return (st) ? &st->iface : NULL;
684}
685
686static struct st_framebuffer *
687st_framebuffer_reuse_or_create(struct gl_framebuffer *fb,
688                               struct st_framebuffer_iface *stfbi)
689{
690   struct st_framebuffer *cur = st_ws_framebuffer(fb), *stfb = NULL;
691
692   /* dummy framebuffers cant be used as st_framebuffer */
693   if (cur && &cur->Base != _mesa_get_incomplete_framebuffer() &&
694       cur->iface == stfbi) {
695      /* reuse the current stfb */
696      st_framebuffer_reference(&stfb, cur);
697   }
698   else {
699      /* create a new one */
700      stfb = st_framebuffer_create(stfbi);
701   }
702
703   return stfb;
704}
705
706static boolean
707st_api_make_current(struct st_api *stapi, struct st_context_iface *stctxi,
708                    struct st_framebuffer_iface *stdrawi,
709                    struct st_framebuffer_iface *streadi)
710{
711   struct st_context *st = (struct st_context *) stctxi;
712   struct st_framebuffer *stdraw, *stread;
713   boolean ret;
714
715   _glapi_check_multithread();
716
717   if (st) {
718      /* reuse or create the draw fb */
719      stdraw = st_framebuffer_reuse_or_create(st->ctx->WinSysDrawBuffer,
720                                              stdrawi);
721      if (streadi != stdrawi) {
722         /* do the same for the read fb */
723         stread = st_framebuffer_reuse_or_create(st->ctx->WinSysReadBuffer,
724                                                 streadi);
725      }
726      else {
727         stread = NULL;
728         /* reuse the draw fb for the read fb */
729         if (stdraw)
730            st_framebuffer_reference(&stread, stdraw);
731      }
732
733      if (stdraw && stread) {
734         st_framebuffer_validate(stdraw, st);
735         if (stread != stdraw)
736            st_framebuffer_validate(stread, st);
737
738         ret = _mesa_make_current(st->ctx, &stdraw->Base, &stread->Base);
739
740         st->draw_stamp = stdraw->stamp - 1;
741         st->read_stamp = stread->stamp - 1;
742         st_context_validate(st, stdraw, stread);
743      }
744      else {
745         struct gl_framebuffer *incomplete = _mesa_get_incomplete_framebuffer();
746         ret = _mesa_make_current(st->ctx, incomplete, incomplete);
747      }
748
749      st_framebuffer_reference(&stdraw, NULL);
750      st_framebuffer_reference(&stread, NULL);
751   }
752   else {
753      ret = _mesa_make_current(NULL, NULL, NULL);
754   }
755
756   return ret;
757}
758
759static st_proc_t
760st_api_get_proc_address(struct st_api *stapi, const char *procname)
761{
762   return (st_proc_t) _glapi_get_proc_address(procname);
763}
764
765static void
766st_api_destroy(struct st_api *stapi)
767{
768}
769
770/**
771 * Flush the front buffer if the current context renders to the front buffer.
772 */
773void
774st_manager_flush_frontbuffer(struct st_context *st)
775{
776   struct st_framebuffer *stfb = st_ws_framebuffer(st->ctx->DrawBuffer);
777   struct st_renderbuffer *strb = NULL;
778
779   if (stfb)
780      strb = st_renderbuffer(stfb->Base.Attachment[BUFFER_FRONT_LEFT].Renderbuffer);
781   if (!strb)
782      return;
783
784   /* never a dummy fb */
785   assert(&stfb->Base != _mesa_get_incomplete_framebuffer());
786   stfb->iface->flush_front(stfb->iface, ST_ATTACHMENT_FRONT_LEFT);
787}
788
789/**
790 * Return the surface of an EGLImage.
791 * FIXME: I think this should operate on resources, not surfaces
792 */
793struct pipe_surface *
794st_manager_get_egl_image_surface(struct st_context *st,
795                                 void *eglimg, unsigned usage)
796{
797   struct st_manager *smapi =
798      (struct st_manager *) st->iface.st_context_private;
799   struct st_egl_image stimg;
800   struct pipe_surface *ps, surf_tmpl;
801
802   if (!smapi || !smapi->get_egl_image)
803      return NULL;
804
805   memset(&stimg, 0, sizeof(stimg));
806   if (!smapi->get_egl_image(smapi, eglimg, &stimg))
807      return NULL;
808
809   u_surface_default_template(&surf_tmpl, stimg.texture, usage);
810   surf_tmpl.u.tex.level = stimg.level;
811   surf_tmpl.u.tex.first_layer = stimg.layer;
812   surf_tmpl.u.tex.last_layer = stimg.layer;
813   ps = st->pipe->create_surface(st->pipe, stimg.texture, &surf_tmpl);
814   pipe_resource_reference(&stimg.texture, NULL);
815
816   return ps;
817}
818
819/**
820 * Re-validate the framebuffers.
821 */
822void
823st_manager_validate_framebuffers(struct st_context *st)
824{
825   struct st_framebuffer *stdraw = st_ws_framebuffer(st->ctx->DrawBuffer);
826   struct st_framebuffer *stread = st_ws_framebuffer(st->ctx->ReadBuffer);
827
828   if (stdraw)
829      st_framebuffer_validate(stdraw, st);
830   if (stread && stread != stdraw)
831      st_framebuffer_validate(stread, st);
832
833   st_context_validate(st, stdraw, stread);
834}
835
836/**
837 * Add a color renderbuffer on demand.
838 */
839boolean
840st_manager_add_color_renderbuffer(struct st_context *st,
841                                  struct gl_framebuffer *fb,
842                                  gl_buffer_index idx)
843{
844   struct st_framebuffer *stfb = st_ws_framebuffer(fb);
845
846   /* FBO */
847   if (!stfb)
848      return FALSE;
849
850   if (stfb->Base.Attachment[idx].Renderbuffer)
851      return TRUE;
852
853   switch (idx) {
854   case BUFFER_FRONT_LEFT:
855   case BUFFER_BACK_LEFT:
856   case BUFFER_FRONT_RIGHT:
857   case BUFFER_BACK_RIGHT:
858      break;
859   default:
860      return FALSE;
861      break;
862   }
863
864   if (!st_framebuffer_add_renderbuffer(stfb, idx))
865      return FALSE;
866
867   st_framebuffer_update_attachments(stfb);
868
869   /*
870    * Force a call to the state tracker manager to validate the
871    * new renderbuffer. It might be that there is a window system
872    * renderbuffer available.
873    */
874   if(stfb->iface)
875      stfb->iface_stamp = p_atomic_read(&stfb->iface->stamp) - 1;
876
877   st_invalidate_state(st->ctx, _NEW_BUFFERS);
878
879   return TRUE;
880}
881
882static const struct st_api st_gl_api = {
883   "Mesa " MESA_VERSION_STRING,
884   ST_API_OPENGL,
885#if FEATURE_GL
886   ST_PROFILE_DEFAULT_MASK |
887#endif
888#if FEATURE_ES1
889   ST_PROFILE_OPENGL_ES1_MASK |
890#endif
891#if FEATURE_ES2
892   ST_PROFILE_OPENGL_ES2_MASK |
893#endif
894   0,
895   0,
896   st_api_destroy,
897   st_api_get_proc_address,
898   st_api_create_context,
899   st_api_make_current,
900   st_api_get_current,
901};
902
903struct st_api *
904st_gl_api_create(void)
905{
906   return (struct st_api *) &st_gl_api;
907}
908