src/mesa/state_tracker/st_cb_fbo.c

   1 /**************************************************************************
   2  *
   3  * Copyright 2007 Tungsten Graphics, Inc., Cedar Park, Texas.
   4  * All Rights Reserved.
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a
   7  * copy of this software and associated documentation files (the
   8  * "Software"), to deal in the Software without restriction, including
   9  * without limitation the rights to use, copy, modify, merge, publish,
  10  * distribute, sub license, and/or sell copies of the Software, and to
  11  * permit persons to whom the Software is furnished to do so, subject to
  12  * the following conditions:
  13  *
  14  * The above copyright notice and this permission notice (including the
  15  * next paragraph) shall be included in all copies or substantial portions
  16  * of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  19  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  20  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
  21  * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR
  22  * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
  23  * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
  24  * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  25  *
  26  **************************************************************************/
  27
  28
  29 /**
  30  * Framebuffer/renderbuffer functions.
  31  *
  32  * \author Brian Paul
  33  */
  34
  35
  36 #include "main/imports.h"
  37 #include "main/context.h"
  38 #include "main/fbobject.h"
  39 #include "main/framebuffer.h"
  40 #include "main/macros.h"
  41 #include "main/mfeatures.h"
  42 #include "main/renderbuffer.h"
  43
  44 #include "pipe/p_context.h"
  45 #include "pipe/p_defines.h"
  46 #include "pipe/p_screen.h"
  47 #include "st_context.h"
  48 #include "st_cb_fbo.h"
  49 #include "st_cb_flush.h"
  50 #include "st_format.h"
  51 #include "st_texture.h"
  52 #include "st_manager.h"
  53
  54 #include "util/u_format.h"
  55 #include "util/u_inlines.h"
  56 #include "util/u_surface.h"
  57
  58
  59 /**
  60  * gl_renderbuffer::AllocStorage()
  61  * This is called to allocate the original drawing surface, and
  62  * during window resize.
  63  */
  64 static GLboolean
  65 st_renderbuffer_alloc_storage(struct gl_context * ctx,
  66                               struct gl_renderbuffer *rb,
  67                               GLenum internalFormat,
  68                               GLuint width, GLuint height)
  69 {
  70    struct st_context *st = st_context(ctx);
  71    struct pipe_context *pipe = st->pipe;
  72    struct pipe_screen *screen = st->pipe->screen;
  73    struct st_renderbuffer *strb = st_renderbuffer(rb);
  74    enum pipe_format format;
  75    struct pipe_surface surf_tmpl;
  76
  77    format = st_choose_renderbuffer_format(screen, internalFormat,
  78                                           rb->NumSamples);
  79
  80    if (format == PIPE_FORMAT_NONE) {
  81       return FALSE;
  82    }
  83
  84    /* init renderbuffer fields */
  85    strb->Base.Width  = width;
  86    strb->Base.Height = height;
  87    strb->Base.Format = st_pipe_format_to_mesa_format(format);
  88    strb->Base._BaseFormat = _mesa_base_fbo_format(ctx, internalFormat);
  89    strb->Base.DataType = st_format_datatype(format);
  90    strb->format = format;
  91
  92    strb->defined = GL_FALSE;  /* undefined contents now */
  93
  94    if (strb->software) {
  95       size_t size;
  96
  97       free(strb->data);
  98
  99       assert(strb->format != PIPE_FORMAT_NONE);
 100
 101       strb->stride = util_format_get_stride(strb->format, width);
 102       size = util_format_get_2d_size(strb->format, strb->stride, height);
 103
 104       strb->data = malloc(size);
 105
 106       return strb->data != NULL;
 107    }
 108    else {
 109       struct pipe_resource template;
 110
 111       /* Free the old surface and texture
 112        */
 113       pipe_surface_reference( &strb->surface, NULL );
 114       pipe_resource_reference( &strb->texture, NULL );
 115       pipe_sampler_view_reference(&strb->sampler_view, NULL);
 116
 117       /* Setup new texture template.
 118        */
 119       memset(&template, 0, sizeof(template));
 120       template.target = st->internal_target;
 121       template.format = format;
 122       template.width0 = width;
 123       template.height0 = height;
 124       template.depth0 = 1;
 125       template.array_size = 1;
 126       template.last_level = 0;
 127       template.nr_samples = rb->NumSamples;
 128       if (util_format_is_depth_or_stencil(format)) {
 129          template.bind = PIPE_BIND_DEPTH_STENCIL;
 130       }
 131       else {
 132          template.bind = (PIPE_BIND_DISPLAY_TARGET |
 133                           PIPE_BIND_RENDER_TARGET);
 134       }
 135
 136       strb->texture = screen->resource_create(screen, &template);
 137
 138       if (!strb->texture)
 139          return FALSE;
 140
 141       memset(&surf_tmpl, 0, sizeof(surf_tmpl));
 142       u_surface_default_template(&surf_tmpl, strb->texture, template.bind);
 143       strb->surface = pipe->create_surface(pipe,
 144                                            strb->texture,
 145                                            &surf_tmpl);
 146       if (strb->surface) {
 147          assert(strb->surface->texture);
 148          assert(strb->surface->format);
 149          assert(strb->surface->width == width);
 150          assert(strb->surface->height == height);
 151       }
 152
 153       return strb->surface != NULL;
 154    }
 155 }
 156
 157
 158 /**
 159  * gl_renderbuffer::Delete()
 160  */
 161 static void
 162 st_renderbuffer_delete(struct gl_renderbuffer *rb)
 163 {
 164    struct st_renderbuffer *strb = st_renderbuffer(rb);
 165    ASSERT(strb);
 166    pipe_surface_reference(&strb->surface, NULL);
 167    pipe_resource_reference(&strb->texture, NULL);
 168    pipe_sampler_view_reference(&strb->sampler_view, NULL);
 169    free(strb->data);
 170    free(strb);
 171 }
 172
 173
 174 /**
 175  * gl_renderbuffer::GetPointer()
 176  */
 177 static void *
 178 null_get_pointer(struct gl_context * ctx, struct gl_renderbuffer *rb,
 179                  GLint x, GLint y)
 180 {
 181    /* By returning NULL we force all software rendering to go through
 182     * the span routines.
 183     */
 184 #if 0
 185    assert(0);  /* Should never get called with softpipe */
 186 #endif
 187    return NULL;
 188 }
 189
 190
 191 /**
 192  * Called via ctx->Driver.NewFramebuffer()
 193  */
 194 static struct gl_framebuffer *
 195 st_new_framebuffer(struct gl_context *ctx, GLuint name)
 196 {
 197    /* XXX not sure we need to subclass gl_framebuffer for pipe */
 198    return _mesa_new_framebuffer(ctx, name);
 199 }
 200
 201
 202 /**
 203  * Called via ctx->Driver.NewRenderbuffer()
 204  */
 205 static struct gl_renderbuffer *
 206 st_new_renderbuffer(struct gl_context *ctx, GLuint name)
 207 {
 208    struct st_renderbuffer *strb = ST_CALLOC_STRUCT(st_renderbuffer);
 209    if (strb) {
 210       _mesa_init_renderbuffer(&strb->Base, name);
 211       strb->Base.Delete = st_renderbuffer_delete;
 212       strb->Base.AllocStorage = st_renderbuffer_alloc_storage;
 213       strb->Base.GetPointer = null_get_pointer;
 214       strb->format = PIPE_FORMAT_NONE;
 215       return &strb->Base;
 216    }
 217    return NULL;
 218 }
 219
 220
 221 /**
 222  * Allocate a renderbuffer for a an on-screen window (not a user-created
 223  * renderbuffer).  The window system code determines the format.
 224  */
 225 struct gl_renderbuffer *
 226 st_new_renderbuffer_fb(enum pipe_format format, int samples, boolean sw)
 227 {
 228    struct st_renderbuffer *strb;
 229
 230    strb = ST_CALLOC_STRUCT(st_renderbuffer);
 231    if (!strb) {
 232       _mesa_error(NULL, GL_OUT_OF_MEMORY, "creating renderbuffer");
 233       return NULL;
 234    }
 235
 236    _mesa_init_renderbuffer(&strb->Base, 0);
 237    strb->Base.ClassID = 0x4242; /* just a unique value */
 238    strb->Base.NumSamples = samples;
 239    strb->Base.Format = st_pipe_format_to_mesa_format(format);
 240    strb->Base._BaseFormat = _mesa_get_format_base_format(strb->Base.Format);
 241    strb->Base.DataType = st_format_datatype(format);
 242    strb->format = format;
 243    strb->software = sw;
 244
 245    switch (format) {
 246    case PIPE_FORMAT_R8G8B8A8_UNORM:
 247    case PIPE_FORMAT_B8G8R8A8_UNORM:
 248    case PIPE_FORMAT_A8R8G8B8_UNORM:
 249    case PIPE_FORMAT_R8G8B8X8_UNORM:
 250    case PIPE_FORMAT_B8G8R8X8_UNORM:
 251    case PIPE_FORMAT_X8R8G8B8_UNORM:
 252    case PIPE_FORMAT_B5G5R5A1_UNORM:
 253    case PIPE_FORMAT_B4G4R4A4_UNORM:
 254    case PIPE_FORMAT_B5G6R5_UNORM:
 255       strb->Base.InternalFormat = GL_RGBA;
 256       break;
 257    case PIPE_FORMAT_Z16_UNORM:
 258       strb->Base.InternalFormat = GL_DEPTH_COMPONENT16;
 259       break;
 260    case PIPE_FORMAT_Z32_UNORM:
 261       strb->Base.InternalFormat = GL_DEPTH_COMPONENT32;
 262       break;
 263    case PIPE_FORMAT_Z24_UNORM_S8_USCALED:
 264    case PIPE_FORMAT_S8_USCALED_Z24_UNORM:
 265    case PIPE_FORMAT_Z24X8_UNORM:
 266    case PIPE_FORMAT_X8Z24_UNORM:
 267       strb->Base.InternalFormat = GL_DEPTH24_STENCIL8_EXT;
 268       break;
 269    case PIPE_FORMAT_S8_USCALED:
 270       strb->Base.InternalFormat = GL_STENCIL_INDEX8_EXT;
 271       break;
 272    case PIPE_FORMAT_R16G16B16A16_SNORM:
 273       /* accum buffer */
 274       strb->Base.InternalFormat = GL_RGBA16_SNORM;
 275       break;
 276    case PIPE_FORMAT_R8_UNORM:
 277       strb->Base.InternalFormat = GL_R8;
 278       break;
 279    case PIPE_FORMAT_R8G8_UNORM:
 280       strb->Base.InternalFormat = GL_RG8;
 281       break;
 282    case PIPE_FORMAT_R16_UNORM:
 283       strb->Base.InternalFormat = GL_R16;
 284       break;
 285    case PIPE_FORMAT_R16G16_UNORM:
 286       strb->Base.InternalFormat = GL_RG16;
 287       break;
 288    default:
 289       _mesa_problem(NULL,
 290                     "Unexpected format in st_new_renderbuffer_fb");
 291       free(strb);
 292       return NULL;
 293    }
 294
 295    /* st-specific methods */
 296    strb->Base.Delete = st_renderbuffer_delete;
 297    strb->Base.AllocStorage = st_renderbuffer_alloc_storage;
 298    strb->Base.GetPointer = null_get_pointer;
 299
 300    /* surface is allocated in st_renderbuffer_alloc_storage() */
 301    strb->surface = NULL;
 302
 303    return &strb->Base;
 304 }
 305
 306
 307
 308
 309 /**
 310  * Called via ctx->Driver.BindFramebufferEXT().
 311  */
 312 static void
 313 st_bind_framebuffer(struct gl_context *ctx, GLenum target,
 314                     struct gl_framebuffer *fb, struct gl_framebuffer *fbread)
 315 {
 316
 317 }
 318
 319 /**
 320  * Called by ctx->Driver.FramebufferRenderbuffer
 321  */
 322 static void
 323 st_framebuffer_renderbuffer(struct gl_context *ctx,
 324                             struct gl_framebuffer *fb,
 325                             GLenum attachment,
 326                             struct gl_renderbuffer *rb)
 327 {
 328    /* XXX no need for derivation? */
 329    _mesa_framebuffer_renderbuffer(ctx, fb, attachment, rb);
 330 }
 331
 332
 333 /**
 334  * Called by ctx->Driver.RenderTexture
 335  */
 336 static void
 337 st_render_texture(struct gl_context *ctx,
 338                   struct gl_framebuffer *fb,
 339                   struct gl_renderbuffer_attachment *att)
 340 {
 341    struct st_context *st = st_context(ctx);
 342    struct pipe_context *pipe = st->pipe;
 343    struct st_renderbuffer *strb;
 344    struct gl_renderbuffer *rb;
 345    struct pipe_resource *pt = st_get_texobj_resource(att->Texture);
 346    struct st_texture_object *stObj;
 347    const struct gl_texture_image *texImage;
 348    struct pipe_surface surf_tmpl;
 349
 350    /* When would this fail?  Perhaps assert? */
 351    if (!pt)
 352       return;
 353
 354    /* get pointer to texture image we're rendeing to */
 355    texImage = _mesa_get_attachment_teximage(att);
 356
 357    /* create new renderbuffer which wraps the texture image */
 358    rb = st_new_renderbuffer(ctx, 0);
 359    if (!rb) {
 360       _mesa_error(ctx, GL_OUT_OF_MEMORY, "glFramebufferTexture()");
 361       return;
 362    }
 363
 364    _mesa_reference_renderbuffer(&att->Renderbuffer, rb);
 365    assert(rb->RefCount == 1);
 366    rb->AllocStorage = NULL; /* should not get called */
 367    strb = st_renderbuffer(rb);
 368
 369    assert(strb->Base.RefCount > 0);
 370
 371    /* get the texture for the texture object */
 372    stObj = st_texture_object(att->Texture);
 373
 374    /* point renderbuffer at texobject */
 375    strb->rtt = stObj;
 376    strb->rtt_level = att->TextureLevel;
 377    strb->rtt_face = att->CubeMapFace;
 378    strb->rtt_slice = att->Zoffset;
 379
 380    rb->Width = texImage->Width2;
 381    rb->Height = texImage->Height2;
 382    rb->_BaseFormat = texImage->_BaseFormat;
 383    /*printf("***** render to texture level %d: %d x %d\n", att->TextureLevel, rb->Width, rb->Height);*/
 384
 385    /*printf("***** pipe texture %d x %d\n", pt->width0, pt->height0);*/
 386
 387    pipe_resource_reference( &strb->texture, pt );
 388
 389    pipe_surface_reference(&strb->surface, NULL);
 390
 391    pipe_sampler_view_reference(&strb->sampler_view,
 392                                st_get_texture_sampler_view(stObj, pipe));
 393
 394    assert(strb->rtt_level <= strb->texture->last_level);
 395
 396    /* new surface for rendering into the texture */
 397    memset(&surf_tmpl, 0, sizeof(surf_tmpl));
 398    surf_tmpl.format = ctx->Color.sRGBEnabled ? strb->texture->format : util_format_linear(strb->texture->format);
 399    surf_tmpl.usage = PIPE_BIND_RENDER_TARGET;
 400    surf_tmpl.u.tex.level = strb->rtt_level;
 401    surf_tmpl.u.tex.first_layer = strb->rtt_face + strb->rtt_slice;
 402    surf_tmpl.u.tex.last_layer = strb->rtt_face + strb->rtt_slice;
 403    strb->surface = pipe->create_surface(pipe,
 404                                         strb->texture,
 405                                         &surf_tmpl);
 406
 407    strb->format = pt->format;
 408
 409    strb->Base.Format = st_pipe_format_to_mesa_format(pt->format);
 410    strb->Base.DataType = st_format_datatype(pt->format);
 411
 412    /*
 413    printf("RENDER TO TEXTURE obj=%p pt=%p surf=%p  %d x %d\n",
 414           att->Texture, pt, strb->surface, rb->Width, rb->Height);
 415    */
 416
 417    /* Invalidate buffer state so that the pipe's framebuffer state
 418     * gets updated.
 419     * That's where the new renderbuffer (which we just created) gets
 420     * passed to the pipe as a (color/depth) render target.
 421     */
 422    st_invalidate_state(ctx, _NEW_BUFFERS);
 423 }
 424
 425
 426 /**
 427  * Called via ctx->Driver.FinishRenderTexture.
 428  */
 429 static void
 430 st_finish_render_texture(struct gl_context *ctx,
 431                          struct gl_renderbuffer_attachment *att)
 432 {
 433    struct st_renderbuffer *strb = st_renderbuffer(att->Renderbuffer);
 434
 435    if (!strb)
 436       return;
 437
 438    strb->rtt = NULL;
 439
 440    /*
 441    printf("FINISH RENDER TO TEXTURE surf=%p\n", strb->surface);
 442    */
 443
 444    /* restore previous framebuffer state */
 445    st_invalidate_state(ctx, _NEW_BUFFERS);
 446 }
 447
 448
 449 /**
 450  * Validate a renderbuffer attachment for a particular set of bindings.
 451  */
 452 static GLboolean
 453 st_validate_attachment(struct gl_context *ctx,
 454                        struct pipe_screen *screen,
 455                        const struct gl_renderbuffer_attachment *att,
 456                        unsigned bindings)
 457 {
 458    const struct st_texture_object *stObj = st_texture_object(att->Texture);
 459    enum pipe_format format;
 460    gl_format texFormat;
 461
 462    /* Only validate texture attachments for now, since
 463     * st_renderbuffer_alloc_storage makes sure that
 464     * the format is supported.
 465     */
 466    if (att->Type != GL_TEXTURE)
 467       return GL_TRUE;
 468
 469    if (!stObj)
 470       return GL_FALSE;
 471
 472    format = stObj->pt->format;
 473    texFormat = _mesa_get_attachment_teximage_const(att)->TexFormat;
 474
 475    /* If the encoding is sRGB and sRGB rendering cannot be enabled,
 476     * check for linear format support instead.
 477     * Later when we create a surface, we change the format to a linear one. */
 478    if (!ctx->Const.sRGBCapable &&
 479        _mesa_get_format_color_encoding(texFormat) == GL_SRGB) {
 480       const gl_format linearFormat = _mesa_get_srgb_format_linear(texFormat);
 481       format = st_mesa_format_to_pipe_format(linearFormat);
 482    }
 483
 484    return screen->is_format_supported(screen, format,
 485                                       PIPE_TEXTURE_2D,
 486                                       stObj->pt->nr_samples, bindings);
 487 }
 488
 489
 490 /**
 491  * Check if two renderbuffer attachments name a combined depth/stencil
 492  * renderbuffer.
 493  */
 494 GLboolean
 495 st_is_depth_stencil_combined(const struct gl_renderbuffer_attachment *depth,
 496                              const struct gl_renderbuffer_attachment *stencil)
 497 {
 498    assert(depth && stencil);
 499
 500    if (depth->Type == stencil->Type) {
 501       if (depth->Type == GL_RENDERBUFFER_EXT &&
 502           depth->Renderbuffer == stencil->Renderbuffer)
 503          return GL_TRUE;
 504
 505       if (depth->Type == GL_TEXTURE &&
 506           depth->Texture == stencil->Texture)
 507          return GL_TRUE;
 508    }
 509
 510    return GL_FALSE;
 511 }
 512
 513
 514 /**
 515  * Check that the framebuffer configuration is valid in terms of what
 516  * the driver can support.
 517  *
 518  * For Gallium we only supports combined Z+stencil, not separate buffers.
 519  */
 520 static void
 521 st_validate_framebuffer(struct gl_context *ctx, struct gl_framebuffer *fb)
 522 {
 523    struct st_context *st = st_context(ctx);
 524    struct pipe_screen *screen = st->pipe->screen;
 525    const struct gl_renderbuffer_attachment *depth =
 526          &fb->Attachment[BUFFER_DEPTH];
 527    const struct gl_renderbuffer_attachment *stencil =
 528          &fb->Attachment[BUFFER_STENCIL];
 529    GLuint i;
 530    enum pipe_format first_format = PIPE_FORMAT_NONE;
 531    boolean mixed_formats =
 532          screen->get_param(screen, PIPE_CAP_MIXED_COLORBUFFER_FORMATS) != 0;
 533
 534    if (depth->Type && stencil->Type && depth->Type != stencil->Type) {
 535       fb->_Status = GL_FRAMEBUFFER_UNSUPPORTED_EXT;
 536       return;
 537    }
 538    if (depth->Type == GL_RENDERBUFFER_EXT &&
 539        stencil->Type == GL_RENDERBUFFER_EXT &&
 540        depth->Renderbuffer != stencil->Renderbuffer) {
 541       fb->_Status = GL_FRAMEBUFFER_UNSUPPORTED_EXT;
 542       return;
 543    }
 544    if (depth->Type == GL_TEXTURE &&
 545        stencil->Type == GL_TEXTURE &&
 546        depth->Texture != stencil->Texture) {
 547       fb->_Status = GL_FRAMEBUFFER_UNSUPPORTED_EXT;
 548       return;
 549    }
 550
 551    if (!st_validate_attachment(ctx,
 552                                screen,
 553                                depth,
 554                                PIPE_BIND_DEPTH_STENCIL)) {
 555       fb->_Status = GL_FRAMEBUFFER_UNSUPPORTED_EXT;
 556       return;
 557    }
 558    if (!st_validate_attachment(ctx,
 559                                screen,
 560                                stencil,
 561                                PIPE_BIND_DEPTH_STENCIL)) {
 562       fb->_Status = GL_FRAMEBUFFER_UNSUPPORTED_EXT;
 563       return;
 564    }
 565    for (i = 0; i < ctx->Const.MaxColorAttachments; i++) {
 566       struct gl_renderbuffer_attachment *att =
 567             &fb->Attachment[BUFFER_COLOR0 + i];
 568       enum pipe_format format;
 569
 570       if (!st_validate_attachment(ctx,
 571                                   screen,
 572                                   att,
 573                                   PIPE_BIND_RENDER_TARGET)) {
 574          fb->_Status = GL_FRAMEBUFFER_UNSUPPORTED_EXT;
 575          return;
 576       }
 577
 578       if (!mixed_formats) {
 579          /* Disallow mixed formats. */
 580          if (att->Type != GL_NONE) {
 581             format = st_renderbuffer(att->Renderbuffer)->surface->format;
 582          } else {
 583             continue;
 584          }
 585
 586          if (first_format == PIPE_FORMAT_NONE) {
 587             first_format = format;
 588          } else if (format != first_format) {
 589             fb->_Status = GL_FRAMEBUFFER_UNSUPPORTED_EXT;
 590             return;
 591          }
 592       }
 593    }
 594 }
 595
 596
 597 /**
 598  * Called via glDrawBuffer.
 599  */
 600 static void
 601 st_DrawBuffers(struct gl_context *ctx, GLsizei count, const GLenum *buffers)
 602 {
 603    struct st_context *st = st_context(ctx);
 604    struct gl_framebuffer *fb = ctx->DrawBuffer;
 605    GLuint i;
 606
 607    (void) count;
 608    (void) buffers;
 609
 610    /* add the renderbuffers on demand */
 611    for (i = 0; i < fb->_NumColorDrawBuffers; i++) {
 612       gl_buffer_index idx = fb->_ColorDrawBufferIndexes[i];
 613       st_manager_add_color_renderbuffer(st, fb, idx);
 614    }
 615 }
 616
 617
 618 /**
 619  * Called via glReadBuffer.
 620  */
 621 static void
 622 st_ReadBuffer(struct gl_context *ctx, GLenum buffer)
 623 {
 624    struct st_context *st = st_context(ctx);
 625    struct gl_framebuffer *fb = ctx->ReadBuffer;
 626
 627    (void) buffer;
 628
 629    /* add the renderbuffer on demand */
 630    st_manager_add_color_renderbuffer(st, fb, fb->_ColorReadBufferIndex);
 631 }
 632
 633
 634 void st_init_fbo_functions(struct dd_function_table *functions)
 635 {
 636 #if FEATURE_EXT_framebuffer_object
 637    functions->NewFramebuffer = st_new_framebuffer;
 638    functions->NewRenderbuffer = st_new_renderbuffer;
 639    functions->BindFramebuffer = st_bind_framebuffer;
 640    functions->FramebufferRenderbuffer = st_framebuffer_renderbuffer;
 641    functions->RenderTexture = st_render_texture;
 642    functions->FinishRenderTexture = st_finish_render_texture;
 643    functions->ValidateFramebuffer = st_validate_framebuffer;
 644 #endif
 645    /* no longer needed by core Mesa, drivers handle resizes...
 646    functions->ResizeBuffers = st_resize_buffers;
 647    */
 648
 649    functions->DrawBuffers = st_DrawBuffers;
 650    functions->ReadBuffer = st_ReadBuffer;
 651 }
 652
 653 /* XXX unused ? */
 654 struct pipe_sampler_view *
 655 st_get_renderbuffer_sampler_view(struct st_renderbuffer *rb,
 656                                  struct pipe_context *pipe)
 657 {
 658    if (!rb->sampler_view) {
 659       rb->sampler_view = st_create_texture_sampler_view(pipe, rb->texture);
 660    }
 661
 662    return rb->sampler_view;
 663 }