src/gallium/drivers/svga/svga_surface.c

   1 /**********************************************************
   2  * Copyright 2008-2009 VMware, Inc.  All rights reserved.
   3  *
   4  * Permission is hereby granted, free of charge, to any person
   5  * obtaining a copy of this software and associated documentation
   6  * files (the "Software"), to deal in the Software without
   7  * restriction, including without limitation the rights to use, copy,
   8  * modify, merge, publish, distribute, sublicense, and/or sell copies
   9  * of the Software, and to permit persons to whom the Software is
  10  * furnished to do so, subject to the following conditions:
  11  *
  12  * The above copyright notice and this permission notice shall be
  13  * included in all copies or substantial portions of the Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  16  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  17  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  18  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  19  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  20  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  21  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  22  * SOFTWARE.
  23  *
  24  **********************************************************/
  25
  26 #include "svga_cmd.h"
  27
  28 #include "pipe/p_state.h"
  29 #include "pipe/p_defines.h"
  30 #include "util/u_inlines.h"
  31 #include "os/os_thread.h"
  32 #include "util/u_bitmask.h"
  33 #include "util/u_format.h"
  34 #include "util/u_math.h"
  35 #include "util/u_memory.h"
  36
  37 #include "svga_format.h"
  38 #include "svga_screen.h"
  39 #include "svga_context.h"
  40 #include "svga_sampler_view.h"
  41 #include "svga_resource_texture.h"
  42 #include "svga_surface.h"
  43 #include "svga_debug.h"
  44
  45 static void svga_mark_surface_dirty(struct pipe_surface *surf);
  46
  47 void
  48 svga_texture_copy_handle(struct svga_context *svga,
  49                          struct svga_winsys_surface *src_handle,
  50                          unsigned src_x, unsigned src_y, unsigned src_z,
  51                          unsigned src_level, unsigned src_layer,
  52                          struct svga_winsys_surface *dst_handle,
  53                          unsigned dst_x, unsigned dst_y, unsigned dst_z,
  54                          unsigned dst_level, unsigned dst_layer,
  55                          unsigned width, unsigned height, unsigned depth)
  56 {
  57    struct svga_surface dst, src;
  58    enum pipe_error ret;
  59    SVGA3dCopyBox box, *boxes;
  60
  61    assert(svga);
  62
  63    src.handle = src_handle;
  64    src.real_level = src_level;
  65    src.real_layer = src_layer;
  66    src.real_zslice = 0;
  67
  68    dst.handle = dst_handle;
  69    dst.real_level = dst_level;
  70    dst.real_layer = dst_layer;
  71    dst.real_zslice = 0;
  72
  73    box.x = dst_x;
  74    box.y = dst_y;
  75    box.z = dst_z;
  76    box.w = width;
  77    box.h = height;
  78    box.d = depth;
  79    box.srcx = src_x;
  80    box.srcy = src_y;
  81    box.srcz = src_z;
  82
  83 /*
  84    SVGA_DBG(DEBUG_VIEWS, "mipcopy src: %p %u (%ux%ux%u), dst: %p %u (%ux%ux%u)\n",
  85             src_handle, src_level, src_x, src_y, src_z,
  86             dst_handle, dst_level, dst_x, dst_y, dst_z);
  87 */
  88
  89    ret = SVGA3D_BeginSurfaceCopy(svga->swc,
  90                                  &src.base,
  91                                  &dst.base,
  92                                  &boxes, 1);
  93    if (ret != PIPE_OK) {
  94       svga_context_flush(svga, NULL);
  95       ret = SVGA3D_BeginSurfaceCopy(svga->swc,
  96                                     &src.base,
  97                                     &dst.base,
  98                                     &boxes, 1);
  99       assert(ret == PIPE_OK);
 100    }
 101    *boxes = box;
 102    SVGA_FIFOCommitAll(svga->swc);
 103 }
 104
 105
 106 struct svga_winsys_surface *
 107 svga_texture_view_surface(struct svga_context *svga,
 108                           struct svga_texture *tex,
 109                           unsigned bind_flags,
 110                           SVGA3dSurfaceFlags flags,
 111                           SVGA3dSurfaceFormat format,
 112                           unsigned start_mip,
 113                           unsigned num_mip,
 114                           int layer_pick,
 115                           unsigned num_layers,
 116                           int zslice_pick,
 117                           struct svga_host_surface_cache_key *key) /* OUT */
 118 {
 119    struct svga_screen *ss = svga_screen(svga->pipe.screen);
 120    struct svga_winsys_surface *handle;
 121    uint32_t i, j;
 122    unsigned z_offset = 0;
 123
 124    SVGA_DBG(DEBUG_PERF,
 125             "svga: Create surface view: layer %d zslice %d mips %d..%d\n",
 126             layer_pick, zslice_pick, start_mip, start_mip+num_mip-1);
 127
 128    key->flags = flags;
 129    key->format = format;
 130    key->numMipLevels = num_mip;
 131    key->size.width = u_minify(tex->b.b.width0, start_mip);
 132    key->size.height = u_minify(tex->b.b.height0, start_mip);
 133    key->size.depth = zslice_pick < 0 ? u_minify(tex->b.b.depth0, start_mip) : 1;
 134    key->cachable = 1;
 135    key->arraySize = 1;
 136    key->numFaces = 1;
 137    key->sampleCount = tex->b.b.nr_samples;
 138
 139    if (key->sampleCount > 1) {
 140       key->flags |= SVGA3D_SURFACE_MASKABLE_ANTIALIAS;
 141    }
 142
 143    if (tex->b.b.target == PIPE_TEXTURE_CUBE && layer_pick < 0) {
 144       key->flags |= SVGA3D_SURFACE_CUBEMAP;
 145       key->numFaces = 6;
 146    } else if (tex->b.b.target == PIPE_TEXTURE_1D_ARRAY ||
 147               tex->b.b.target == PIPE_TEXTURE_2D_ARRAY) {
 148       key->arraySize = num_layers;
 149    }
 150
 151    if (key->format == SVGA3D_FORMAT_INVALID) {
 152       key->cachable = 0;
 153       return NULL;
 154    }
 155
 156    SVGA_DBG(DEBUG_DMA, "surface_create for texture view\n");
 157    handle = svga_screen_surface_create(ss, bind_flags, PIPE_USAGE_DEFAULT, key);
 158    if (!handle) {
 159       key->cachable = 0;
 160       return NULL;
 161    }
 162
 163    SVGA_DBG(DEBUG_DMA, " --> got sid %p (texture view)\n", handle);
 164
 165    if (layer_pick < 0)
 166       layer_pick = 0;
 167
 168    if (zslice_pick >= 0)
 169       z_offset = zslice_pick;
 170
 171    for (i = 0; i < key->numMipLevels; i++) {
 172       for (j = 0; j < key->numFaces * key->arraySize; j++) {
 173          if (svga_is_texture_level_defined(tex, j + layer_pick, i + start_mip)) {
 174             unsigned depth = (zslice_pick < 0 ?
 175                               u_minify(tex->b.b.depth0, i + start_mip) :
 176                               1);
 177
 178             svga_texture_copy_handle(svga,
 179                                      tex->handle,
 180                                      0, 0, z_offset,
 181                                      i + start_mip,
 182                                      j + layer_pick,
 183                                      handle, 0, 0, 0, i, j,
 184                                      u_minify(tex->b.b.width0, i + start_mip),
 185                                      u_minify(tex->b.b.height0, i + start_mip),
 186                                      depth);
 187          }
 188       }
 189    }
 190
 191    return handle;
 192 }
 193
 194
 195 /**
 196  * A helper function to create a surface view.
 197  * The view boolean flag specifies whether svga_texture_view_surface()
 198  * will be called to create a cloned surface and resource for the view.
 199  */
 200 static struct pipe_surface *
 201 svga_create_surface_view(struct pipe_context *pipe,
 202                          struct pipe_resource *pt,
 203                          const struct pipe_surface *surf_tmpl,
 204                          boolean view)
 205 {
 206    struct svga_context *svga = svga_context(pipe);
 207    struct svga_texture *tex = svga_texture(pt);
 208    struct pipe_screen *screen = pipe->screen;
 209    struct svga_screen *ss = svga_screen(screen);
 210    struct svga_surface *s;
 211    unsigned layer, zslice, bind;
 212    unsigned nlayers = 1;
 213    SVGA3dSurfaceFlags flags = 0;
 214    SVGA3dSurfaceFormat format;
 215
 216    s = CALLOC_STRUCT(svga_surface);
 217    if (!s)
 218       return NULL;
 219
 220    if (pt->target == PIPE_TEXTURE_CUBE) {
 221       layer = surf_tmpl->u.tex.first_layer;
 222       zslice = 0;
 223    }
 224    else if (pt->target == PIPE_TEXTURE_1D_ARRAY ||
 225             pt->target == PIPE_TEXTURE_2D_ARRAY) {
 226       layer = surf_tmpl->u.tex.first_layer;
 227       zslice = 0;
 228       nlayers = surf_tmpl->u.tex.last_layer - surf_tmpl->u.tex.first_layer + 1;
 229    }
 230    else {
 231       layer = 0;
 232       zslice = surf_tmpl->u.tex.first_layer;
 233    }
 234
 235    pipe_reference_init(&s->base.reference, 1);
 236    pipe_resource_reference(&s->base.texture, pt);
 237    s->base.context = pipe;
 238    s->base.format = surf_tmpl->format;
 239    s->base.width = u_minify(pt->width0, surf_tmpl->u.tex.level);
 240    s->base.height = u_minify(pt->height0, surf_tmpl->u.tex.level);
 241    s->base.u.tex.level = surf_tmpl->u.tex.level;
 242    s->base.u.tex.first_layer = surf_tmpl->u.tex.first_layer;
 243    s->base.u.tex.last_layer = surf_tmpl->u.tex.last_layer;
 244    s->view_id = SVGA3D_INVALID_ID;
 245
 246    s->backed = NULL;
 247
 248    if (util_format_is_depth_or_stencil(surf_tmpl->format)) {
 249       flags = SVGA3D_SURFACE_HINT_DEPTHSTENCIL |
 250               SVGA3D_SURFACE_BIND_DEPTH_STENCIL;
 251       bind = PIPE_BIND_DEPTH_STENCIL;
 252    }
 253    else {
 254       flags = SVGA3D_SURFACE_HINT_RENDERTARGET |
 255               SVGA3D_SURFACE_BIND_RENDER_TARGET;
 256       bind = PIPE_BIND_RENDER_TARGET;
 257    }
 258
 259    if (tex->imported)
 260       format = tex->key.format;
 261    else
 262       format = svga_translate_format(ss, surf_tmpl->format, bind);
 263
 264    assert(format != SVGA3D_FORMAT_INVALID);
 265
 266    if (view) {
 267       SVGA_DBG(DEBUG_VIEWS, "svga: Surface view: yes %p, level %u layer %u z %u, %p\n",
 268                pt, surf_tmpl->u.tex.level, layer, zslice, s);
 269
 270       if (svga_have_vgpu10(svga)) {
 271          switch (pt->target) {
 272          case PIPE_TEXTURE_1D:
 273             flags |= SVGA3D_SURFACE_1D;
 274             break;
 275          case PIPE_TEXTURE_1D_ARRAY:
 276             flags |= SVGA3D_SURFACE_1D | SVGA3D_SURFACE_ARRAY;
 277             break;
 278          case PIPE_TEXTURE_2D_ARRAY:
 279             flags |= SVGA3D_SURFACE_ARRAY;
 280             break;
 281          case PIPE_TEXTURE_3D:
 282             flags |= SVGA3D_SURFACE_VOLUME;
 283             break;
 284          case PIPE_TEXTURE_CUBE:
 285             if (nlayers == 6)
 286                flags |= SVGA3D_SURFACE_CUBEMAP;
 287             break;
 288          default:
 289             break;
 290          }
 291       }
 292
 293       /* When we clone the surface view resource, use the format used in
 294        * the creation of the original resource.
 295        */
 296       s->handle = svga_texture_view_surface(svga, tex, bind, flags, tex->key.format,
 297                                             surf_tmpl->u.tex.level, 1,
 298                                             layer, nlayers, zslice, &s->key);
 299       if (!s->handle) {
 300          FREE(s);
 301          return NULL;
 302       }
 303
 304       s->key.format = format;
 305       s->real_layer = 0;
 306       s->real_level = 0;
 307       s->real_zslice = 0;
 308    } else {
 309       SVGA_DBG(DEBUG_VIEWS, "svga: Surface view: no %p, level %u, layer %u, z %u, %p\n",
 310                pt, surf_tmpl->u.tex.level, layer, zslice, s);
 311
 312       memset(&s->key, 0, sizeof s->key);
 313       s->key.format = format;
 314       s->handle = tex->handle;
 315       s->real_layer = layer;
 316       s->real_zslice = zslice;
 317       s->real_level = surf_tmpl->u.tex.level;
 318    }
 319
 320    return &s->base;
 321 }
 322
 323
 324 static struct pipe_surface *
 325 svga_create_surface(struct pipe_context *pipe,
 326                     struct pipe_resource *pt,
 327                     const struct pipe_surface *surf_tmpl)
 328 {
 329    struct svga_context *svga = svga_context(pipe);
 330    struct pipe_screen *screen = pipe->screen;
 331    boolean view = FALSE;
 332
 333    if (svga_screen(screen)->debug.force_surface_view)
 334       view = TRUE;
 335
 336    if (surf_tmpl->u.tex.level != 0 &&
 337        svga_screen(screen)->debug.force_level_surface_view)
 338       view = TRUE;
 339
 340    if (pt->target == PIPE_TEXTURE_3D)
 341       view = TRUE;
 342
 343    if (svga_have_vgpu10(svga) || svga_screen(screen)->debug.no_surface_view)
 344       view = FALSE;
 345
 346    return svga_create_surface_view(pipe, pt, surf_tmpl, view);
 347 }
 348
 349
 350 /**
 351  * Clone the surface view and its associated resource.
 352  */
 353 static struct svga_surface *
 354 create_backed_surface_view(struct svga_context *svga, struct svga_surface *s)
 355 {
 356    struct svga_surface *bs = s->backed;
 357
 358    if (bs == NULL) {
 359       struct svga_texture *tex = svga_texture(s->base.texture);
 360       struct pipe_surface *backed_view;
 361
 362       backed_view = svga_create_surface_view(&svga->pipe,
 363                                              &tex->b.b,
 364                                              &s->base,
 365                                              TRUE);
 366       if (!backed_view)
 367          return NULL;
 368
 369       bs = svga_surface(backed_view);
 370       s->backed = bs;
 371    }
 372
 373    svga_mark_surface_dirty(&bs->base);
 374
 375    return bs;
 376 }
 377
 378 /**
 379  * Create a DX RenderTarget/DepthStencil View for the given surface,
 380  * if needed.
 381  */
 382 struct pipe_surface *
 383 svga_validate_surface_view(struct svga_context *svga, struct svga_surface *s)
 384 {
 385    enum pipe_error ret = PIPE_OK;
 386    unsigned shader;
 387
 388    assert(svga_have_vgpu10(svga));
 389
 390    /**
 391     * DX spec explicitly specifies that no resource can be bound to a render
 392     * target view and a shader resource view simultanously.
 393     * So first check if the resource bound to this surface view collides with
 394     * a sampler view. If so, then we will clone this surface view and its
 395     * associated resource. We will then use the cloned surface view for
 396     * render target.
 397     */
 398    for (shader = PIPE_SHADER_VERTEX; shader <= PIPE_SHADER_GEOMETRY; shader++) {
 399       if (svga_check_sampler_view_resource_collision(svga, s->handle, shader)) {
 400          SVGA_DBG(DEBUG_VIEWS,
 401                   "same resource used in shaderResource and renderTarget 0x%x\n",
 402                   s->handle);
 403          s = create_backed_surface_view(svga, s);
 404          if (!s)
 405             return NULL;
 406
 407          break;
 408       }
 409    }
 410
 411    if (s->view_id == SVGA3D_INVALID_ID) {
 412       SVGA3dResourceType resType;
 413       SVGA3dRenderTargetViewDesc desc;
 414
 415       desc.tex.mipSlice = s->real_level;
 416       desc.tex.firstArraySlice = s->real_layer + s->real_zslice;
 417       desc.tex.arraySize =
 418          s->base.u.tex.last_layer - s->base.u.tex.first_layer + 1;
 419
 420       s->view_id = util_bitmask_add(svga->surface_view_id_bm);
 421
 422       switch (s->base.texture->target) {
 423       case PIPE_TEXTURE_1D:
 424       case PIPE_TEXTURE_1D_ARRAY:
 425          resType = SVGA3D_RESOURCE_TEXTURE1D;
 426          break;
 427       case PIPE_TEXTURE_RECT:
 428       case PIPE_TEXTURE_2D:
 429       case PIPE_TEXTURE_2D_ARRAY:
 430       case PIPE_TEXTURE_CUBE:
 431          /* drawing to cube map is treated as drawing to 2D array */
 432          resType = SVGA3D_RESOURCE_TEXTURE2D;
 433          break;
 434       case PIPE_TEXTURE_3D:
 435          resType = SVGA3D_RESOURCE_TEXTURE3D;
 436          break;
 437       default:
 438          assert(!"Unexpected texture target");
 439          resType = SVGA3D_RESOURCE_TEXTURE2D;
 440       }
 441
 442       if (util_format_is_depth_or_stencil(s->base.format)) {
 443          ret = SVGA3D_vgpu10_DefineDepthStencilView(svga->swc,
 444                                                     s->view_id,
 445                                                     s->handle,
 446                                                     s->key.format,
 447                                                     resType,
 448                                                     &desc);
 449       }
 450       else {
 451          ret = SVGA3D_vgpu10_DefineRenderTargetView(svga->swc,
 452                                                     s->view_id,
 453                                                     s->handle,
 454                                                     s->key.format,
 455                                                     resType,
 456                                                     &desc);
 457       }
 458
 459       if (ret != PIPE_OK) {
 460          util_bitmask_clear(svga->surface_view_id_bm, s->view_id);
 461          s->view_id = SVGA3D_INVALID_ID;
 462          return NULL;
 463       }
 464    }
 465    return &s->base;
 466 }
 467
 468
 469
 470 static void
 471 svga_surface_destroy(struct pipe_context *pipe,
 472                      struct pipe_surface *surf)
 473 {
 474    struct svga_context *svga = svga_context(pipe);
 475    struct svga_surface *s = svga_surface(surf);
 476    struct svga_texture *t = svga_texture(surf->texture);
 477    struct svga_screen *ss = svga_screen(surf->texture->screen);
 478    enum pipe_error ret = PIPE_OK;
 479
 480    /* Destroy the backed view surface if it exists */
 481    if (s->backed) {
 482       svga_surface_destroy(pipe, &s->backed->base);
 483       s->backed = NULL;
 484    }
 485
 486    if (s->handle != t->handle) {
 487       SVGA_DBG(DEBUG_DMA, "unref sid %p (tex surface)\n", s->handle);
 488       svga_screen_surface_destroy(ss, &s->key, &s->handle);
 489    }
 490
 491    if (s->view_id != SVGA3D_INVALID_ID) {
 492       unsigned try;
 493
 494       assert(svga_have_vgpu10(svga));
 495       for (try = 0; try < 2; try++) {
 496          if (util_format_is_depth_or_stencil(s->base.format)) {
 497             ret = SVGA3D_vgpu10_DestroyDepthStencilView(svga->swc, s->view_id);
 498          }
 499          else {
 500             ret = SVGA3D_vgpu10_DestroyRenderTargetView(svga->swc, s->view_id);
 501          }
 502          if (ret == PIPE_OK)
 503             break;
 504          svga_context_flush(svga, NULL);
 505       }
 506       assert(ret == PIPE_OK);
 507       util_bitmask_clear(svga->surface_view_id_bm, s->view_id);
 508    }
 509
 510    pipe_resource_reference(&surf->texture, NULL);
 511    FREE(surf);
 512 }
 513
 514
 515 static void
 516 svga_mark_surface_dirty(struct pipe_surface *surf)
 517 {
 518    struct svga_surface *s = svga_surface(surf);
 519    struct svga_texture *tex = svga_texture(surf->texture);
 520
 521    if (!s->dirty) {
 522       s->dirty = TRUE;
 523
 524       if (s->handle == tex->handle) {
 525          /* hmm so 3d textures always have all their slices marked ? */
 526          svga_define_texture_level(tex, surf->u.tex.first_layer,
 527                                    surf->u.tex.level);
 528       }
 529       else {
 530          /* this will happen later in svga_propagate_surface */
 531       }
 532    }
 533
 534    /* Increment the view_age and texture age for this surface's mipmap
 535     * level so that any sampler views into the texture are re-validated too.
 536     */
 537    svga_age_texture_view(tex, surf->u.tex.level);
 538 }
 539
 540
 541 void
 542 svga_mark_surfaces_dirty(struct svga_context *svga)
 543 {
 544    struct svga_screen *svgascreen = svga_screen(svga->pipe.screen);
 545    unsigned i;
 546
 547    for (i = 0; i < svgascreen->max_color_buffers; i++) {
 548       if (svga->curr.framebuffer.cbufs[i])
 549          svga_mark_surface_dirty(svga->curr.framebuffer.cbufs[i]);
 550    }
 551    if (svga->curr.framebuffer.zsbuf)
 552       svga_mark_surface_dirty(svga->curr.framebuffer.zsbuf);
 553 }
 554
 555
 556 /**
 557  * Progagate any changes from surfaces to texture.
 558  * pipe is optional context to inline the blit command in.
 559  */
 560 void
 561 svga_propagate_surface(struct svga_context *svga, struct pipe_surface *surf)
 562 {
 563    struct svga_surface *s = svga_surface(surf);
 564    struct svga_texture *tex = svga_texture(surf->texture);
 565    struct svga_screen *ss = svga_screen(surf->texture->screen);
 566    unsigned zslice, layer;
 567    unsigned nlayers = 1;
 568    unsigned i;
 569
 570    if (!s->dirty)
 571       return;
 572
 573    if (surf->texture->target == PIPE_TEXTURE_CUBE) {
 574       zslice = 0;
 575       layer = surf->u.tex.first_layer;
 576    }
 577    else if (surf->texture->target == PIPE_TEXTURE_1D_ARRAY ||
 578             surf->texture->target == PIPE_TEXTURE_2D_ARRAY) {
 579       zslice = 0;
 580       layer = surf->u.tex.first_layer;
 581       nlayers = surf->u.tex.last_layer - surf->u.tex.first_layer + 1;
 582    }
 583    else {
 584       zslice = surf->u.tex.first_layer;
 585       layer = 0;
 586    }
 587
 588    s->dirty = FALSE;
 589    ss->texture_timestamp++;
 590    svga_age_texture_view(tex, surf->u.tex.level);
 591
 592    if (s->handle != tex->handle) {
 593       SVGA_DBG(DEBUG_VIEWS,
 594                "svga: Surface propagate: tex %p, level %u, from %p\n",
 595                tex, surf->u.tex.level, surf);
 596       for (i = 0; i < nlayers; i++) {
 597          svga_texture_copy_handle(svga,
 598                                   s->handle, 0, 0, 0, s->real_level, s->real_layer + i,
 599                                   tex->handle, 0, 0, zslice, surf->u.tex.level, layer + i,
 600                                   u_minify(tex->b.b.width0, surf->u.tex.level),
 601                                   u_minify(tex->b.b.height0, surf->u.tex.level), 1);
 602          svga_define_texture_level(tex, layer + i, surf->u.tex.level);
 603       }
 604    }
 605 }
 606
 607
 608 /**
 609  * Check if we should call svga_propagate_surface on the surface.
 610  */
 611 boolean
 612 svga_surface_needs_propagation(const struct pipe_surface *surf)
 613 {
 614    const struct svga_surface *s = svga_surface_const(surf);
 615    struct svga_texture *tex = svga_texture(surf->texture);
 616
 617    return s->dirty && s->handle != tex->handle;
 618 }
 619
 620
 621 static void
 622 svga_get_sample_position(struct pipe_context *context,
 623                          unsigned sample_count, unsigned sample_index,
 624                          float *pos_out)
 625 {
 626    /* We can't actually query the device to learn the sample positions.
 627     * These were grabbed from nvidia's driver.
 628     */
 629    static const float pos1[1][2] = {
 630       { 0.5, 0.5 }
 631    };
 632    static const float pos4[4][2] = {
 633       { 0.375000, 0.125000 },
 634       { 0.875000, 0.375000 },
 635       { 0.125000, 0.625000 },
 636       { 0.625000, 0.875000 }
 637    };
 638    static const float pos8[8][2] = {
 639       { 0.562500, 0.312500 },
 640       { 0.437500, 0.687500 },
 641       { 0.812500, 0.562500 },
 642       { 0.312500, 0.187500 },
 643       { 0.187500, 0.812500 },
 644       { 0.062500, 0.437500 },
 645       { 0.687500, 0.937500 },
 646       { 0.937500, 0.062500 }
 647    };
 648    static const float pos16[16][2] = {
 649       { 0.187500, 0.062500 },
 650       { 0.437500, 0.187500 },
 651       { 0.062500, 0.312500 },
 652       { 0.312500, 0.437500 },
 653       { 0.687500, 0.062500 },
 654       { 0.937500, 0.187500 },
 655       { 0.562500, 0.312500 },
 656       { 0.812500, 0.437500 },
 657       { 0.187500, 0.562500 },
 658       { 0.437500, 0.687500 },
 659       { 0.062500, 0.812500 },
 660       { 0.312500, 0.937500 },
 661       { 0.687500, 0.562500 },
 662       { 0.937500, 0.687500 },
 663       { 0.562500, 0.812500 },
 664       { 0.812500, 0.937500 }
 665    };
 666    const float (*positions)[2];
 667
 668    switch (sample_count) {
 669    case 4:
 670       positions = pos4;
 671       break;
 672    case 8:
 673       positions = pos8;
 674       break;
 675    case 16:
 676       positions = pos16;
 677       break;
 678    default:
 679       positions = pos1;
 680    }
 681
 682    pos_out[0] = positions[sample_index][0];
 683    pos_out[1] = positions[sample_index][1];
 684 }
 685
 686
 687 void
 688 svga_init_surface_functions(struct svga_context *svga)
 689 {
 690    svga->pipe.create_surface = svga_create_surface;
 691    svga->pipe.surface_destroy = svga_surface_destroy;
 692    svga->pipe.get_sample_position = svga_get_sample_position;
 693 }