src/gallium/state_trackers/python/p_context.i

   1  /**************************************************************************
   2  *
   3  * Copyright 2008 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  * @file
  30  * SWIG interface definion for Gallium types.
  31  *
  32  * @author Jose Fonseca <jrfonseca@tungstengraphics.com>
  33  */
  34
  35 %nodefaultctor st_context;
  36 %nodefaultdtor st_context;
  37
  38 struct st_context {
  39 };
  40
  41 %extend st_context {
  42
  43    ~st_context() {
  44       st_context_destroy($self);
  45    }
  46
  47    /*
  48     * State functions (create/bind/destroy state objects)
  49     */
  50
  51    void set_blend( const struct pipe_blend_state *state ) {
  52       cso_set_blend($self->cso, state);
  53    }
  54
  55    void set_fragment_sampler( unsigned index, const struct pipe_sampler_state *state ) {
  56       cso_single_sampler($self->cso, index, state);
  57       cso_single_sampler_done($self->cso);
  58    }
  59
  60    void set_vertex_sampler( unsigned index, const struct pipe_sampler_state *state ) {
  61       cso_single_vertex_sampler($self->cso, index, state);
  62       cso_single_vertex_sampler_done($self->cso);
  63    }
  64
  65    void set_rasterizer( const struct pipe_rasterizer_state *state ) {
  66       cso_set_rasterizer($self->cso, state);
  67    }
  68
  69    void set_depth_stencil_alpha(const struct pipe_depth_stencil_alpha_state *state) {
  70       cso_set_depth_stencil_alpha($self->cso, state);
  71    }
  72
  73    void set_fragment_shader( const struct pipe_shader_state *state ) {
  74       void *fs;
  75
  76       if(!state) {
  77          cso_set_fragment_shader_handle($self->cso, NULL);
  78          return;
  79       }
  80
  81       fs = $self->pipe->create_fs_state($self->pipe, state);
  82       if(!fs)
  83          return;
  84
  85       if(cso_set_fragment_shader_handle($self->cso, fs) != PIPE_OK)
  86          return;
  87
  88       cso_delete_fragment_shader($self->cso, $self->fs);
  89       $self->fs = fs;
  90    }
  91
  92    void set_vertex_shader( const struct pipe_shader_state *state ) {
  93       void *vs;
  94
  95       if(!state) {
  96          cso_set_vertex_shader_handle($self->cso, NULL);
  97          return;
  98       }
  99
 100       vs = $self->pipe->create_vs_state($self->pipe, state);
 101       if(!vs)
 102          return;
 103
 104       if(cso_set_vertex_shader_handle($self->cso, vs) != PIPE_OK)
 105          return;
 106
 107       cso_delete_vertex_shader($self->cso, $self->vs);
 108       $self->vs = vs;
 109    }
 110
 111    void set_geometry_shader( const struct pipe_shader_state *state ) {
 112       void *gs;
 113
 114       if(!state) {
 115          cso_set_geometry_shader_handle($self->cso, NULL);
 116          return;
 117       }
 118
 119       gs = $self->pipe->create_gs_state($self->pipe, state);
 120       if(!gs)
 121          return;
 122
 123       if(cso_set_geometry_shader_handle($self->cso, gs) != PIPE_OK)
 124          return;
 125
 126       cso_delete_geometry_shader($self->cso, $self->gs);
 127       $self->gs = gs;
 128    }
 129
 130    struct pipe_sampler_view *
 131    create_sampler_view(struct pipe_resource *texture,
 132                        enum pipe_format format = PIPE_FORMAT_NONE,
 133                        unsigned first_level = 0,
 134                        unsigned last_level = ~0,
 135                        unsigned first_layer = 0,
 136                        unsigned last_layer = ~0,
 137                        unsigned swizzle_r = 0,
 138                        unsigned swizzle_g = 1,
 139                        unsigned swizzle_b = 2,
 140                        unsigned swizzle_a = 3)
 141    {
 142       struct pipe_context *pipe = $self->pipe;
 143       struct pipe_sampler_view templat;
 144
 145       memset(&templat, 0, sizeof templat);
 146       if (format == PIPE_FORMAT_NONE) {
 147          templat.format = texture->format;
 148       } else {
 149          templat.format = format;
 150       }
 151       templat.u.tex.last_level = MIN2(last_level, texture->last_level);
 152       templat.u.tex.first_level = first_level;
 153       templat.u.tex.first_layer = first_layer;
 154       templat.u.tex.last_layer = last_layer;
 155       templat.swizzle_r = swizzle_r;
 156       templat.swizzle_g = swizzle_g;
 157       templat.swizzle_b = swizzle_b;
 158       templat.swizzle_a = swizzle_a;
 159
 160       return pipe->create_sampler_view(pipe, texture, &templat);
 161    }
 162
 163    void
 164    sampler_view_destroy(struct pipe_context *ctx,
 165                         struct pipe_sampler_view *view)
 166    {
 167       struct pipe_context *pipe = $self->pipe;
 168
 169       pipe->sampler_view_destroy(pipe, view);
 170    }
 171
 172    /*
 173     * Parameter-like state (or properties)
 174     */
 175
 176    void set_blend_color(const struct pipe_blend_color *state ) {
 177       cso_set_blend_color($self->cso, state);
 178    }
 179
 180    void set_stencil_ref(const struct pipe_stencil_ref *state ) {
 181       cso_set_stencil_ref($self->cso, state);
 182    }
 183
 184    void set_clip(const struct pipe_clip_state *state ) {
 185       $self->pipe->set_clip_state($self->pipe, state);
 186    }
 187
 188    void set_constant_buffer(unsigned shader, unsigned index,
 189                             struct pipe_resource *buffer )
 190    {
 191       $self->pipe->set_constant_buffer($self->pipe, shader, index, buffer);
 192    }
 193
 194    void set_framebuffer(const struct pipe_framebuffer_state *state )
 195    {
 196       memcpy(&$self->framebuffer, state, sizeof *state);
 197       cso_set_framebuffer($self->cso, state);
 198    }
 199
 200    void set_polygon_stipple(const struct pipe_poly_stipple *state ) {
 201       $self->pipe->set_polygon_stipple($self->pipe, state);
 202    }
 203
 204    void set_scissor(const struct pipe_scissor_state *state ) {
 205       $self->pipe->set_scissor_state($self->pipe, state);
 206    }
 207
 208    void set_viewport(const struct pipe_viewport_state *state) {
 209       cso_set_viewport($self->cso, state);
 210    }
 211
 212    void set_fragment_sampler_view(unsigned index,
 213                                   struct pipe_sampler_view *view)
 214    {
 215       pipe_sampler_view_reference(&$self->fragment_sampler_views[index], view);
 216
 217       $self->pipe->set_fragment_sampler_views($self->pipe,
 218                                               PIPE_MAX_SAMPLERS,
 219                                               $self->fragment_sampler_views);
 220    }
 221
 222    void set_vertex_sampler_view(unsigned index,
 223                                 struct pipe_sampler_view *view)
 224    {
 225       pipe_sampler_view_reference(&$self->vertex_sampler_views[index], view);
 226
 227       $self->pipe->set_vertex_sampler_views($self->pipe,
 228                                             PIPE_MAX_VERTEX_SAMPLERS,
 229                                             $self->vertex_sampler_views);
 230    }
 231
 232    void set_fragment_sampler_texture(unsigned index,
 233                                      struct pipe_resource *texture) {
 234       struct pipe_sampler_view templ;
 235
 236       if(!texture)
 237          texture = $self->default_texture;
 238       pipe_sampler_view_reference(&$self->fragment_sampler_views[index], NULL);
 239       u_sampler_view_default_template(&templ,
 240                                       texture,
 241                                       texture->format);
 242       $self->fragment_sampler_views[index] = $self->pipe->create_sampler_view($self->pipe,
 243                                                                               texture,
 244                                                                               &templ);
 245       $self->pipe->set_fragment_sampler_views($self->pipe,
 246                                               PIPE_MAX_SAMPLERS,
 247                                               $self->fragment_sampler_views);
 248    }
 249
 250    void set_vertex_sampler_texture(unsigned index,
 251                                    struct pipe_resource *texture) {
 252       struct pipe_sampler_view templ;
 253
 254       if(!texture)
 255          texture = $self->default_texture;
 256       pipe_sampler_view_reference(&$self->vertex_sampler_views[index], NULL);
 257       u_sampler_view_default_template(&templ,
 258                                       texture,
 259                                       texture->format);
 260       $self->vertex_sampler_views[index] = $self->pipe->create_sampler_view($self->pipe,
 261                                                                             texture,
 262                                                                             &templ);
 263
 264       $self->pipe->set_vertex_sampler_views($self->pipe,
 265                                             PIPE_MAX_VERTEX_SAMPLERS,
 266                                             $self->vertex_sampler_views);
 267    }
 268
 269    void set_vertex_buffer(unsigned index,
 270                           unsigned stride,
 271                           unsigned buffer_offset,
 272                           struct pipe_resource *buffer)
 273    {
 274       unsigned i;
 275       struct pipe_vertex_buffer state;
 276
 277       memset(&state, 0, sizeof(state));
 278       state.stride = stride;
 279       state.buffer_offset = buffer_offset;
 280       state.buffer = buffer;
 281
 282       memcpy(&$self->vertex_buffers[index], &state, sizeof(state));
 283
 284       for(i = 0; i < PIPE_MAX_ATTRIBS; ++i)
 285          if(self->vertex_buffers[i].buffer)
 286             $self->num_vertex_buffers = i + 1;
 287
 288       $self->pipe->set_vertex_buffers($self->pipe,
 289                                       $self->num_vertex_buffers,
 290                                       $self->vertex_buffers);
 291    }
 292
 293    void set_index_buffer(unsigned index_size,
 294                          unsigned offset,
 295                          struct pipe_resource *buffer)
 296    {
 297       struct pipe_index_buffer ib;
 298
 299       memset(&ib, 0, sizeof(ib));
 300       ib.index_size = index_size;
 301       ib.offset = offset;
 302       ib.buffer = buffer;
 303
 304       $self->pipe->set_index_buffer($self->pipe, &ib);
 305    }
 306
 307    void set_vertex_element(unsigned index,
 308                            const struct pipe_vertex_element *element)
 309    {
 310       memcpy(&$self->vertex_elements[index], element, sizeof(*element));
 311    }
 312
 313    void set_vertex_elements(unsigned num)
 314    {
 315       $self->num_vertex_elements = num;
 316       cso_set_vertex_elements($self->cso,
 317                               $self->num_vertex_elements,
 318                               $self->vertex_elements);
 319    }
 320
 321    /*
 322     * Draw functions
 323     */
 324
 325    void draw_arrays(unsigned mode, unsigned start, unsigned count) {
 326       util_draw_arrays($self->pipe, mode, start, count);
 327    }
 328
 329    void draw_vbo(const struct pipe_draw_info *info)
 330    {
 331       $self->pipe->draw_vbo($self->pipe, info);
 332    }
 333
 334    void draw_vertices(unsigned prim,
 335                       unsigned num_verts,
 336                       unsigned num_attribs,
 337                       const float *vertices)
 338    {
 339       struct pipe_context *pipe = $self->pipe;
 340       struct pipe_screen *screen = pipe->screen;
 341       struct pipe_resource *vbuf;
 342       struct pipe_transfer *transfer;
 343       struct pipe_vertex_element velements[PIPE_MAX_ATTRIBS];
 344       struct pipe_vertex_buffer vbuffer;
 345       float *map;
 346       unsigned size;
 347       unsigned i;
 348
 349       size = num_verts * num_attribs * 4 * sizeof(float);
 350
 351       vbuf = pipe_buffer_create(screen,
 352                                 PIPE_BIND_VERTEX_BUFFER,
 353                                 PIPE_USAGE_STATIC,
 354                                 size);
 355       if(!vbuf)
 356          goto error1;
 357
 358       map = pipe_buffer_map(pipe, vbuf, PIPE_TRANSFER_WRITE, &transfer);
 359       if (!map)
 360          goto error2;
 361       memcpy(map, vertices, size);
 362       pipe_buffer_unmap(pipe, transfer);
 363
 364       cso_save_vertex_elements($self->cso);
 365
 366       /* tell pipe about the vertex attributes */
 367       for (i = 0; i < num_attribs; i++) {
 368          velements[i].src_offset = i * 4 * sizeof(float);
 369          velements[i].instance_divisor = 0;
 370          velements[i].vertex_buffer_index = 0;
 371          velements[i].src_format = PIPE_FORMAT_R32G32B32A32_FLOAT;
 372       }
 373       cso_set_vertex_elements($self->cso, num_attribs, velements);
 374
 375       /* tell pipe about the vertex buffer */
 376       memset(&vbuffer, 0, sizeof(vbuffer));
 377       vbuffer.buffer = vbuf;
 378       vbuffer.stride = num_attribs * 4 * sizeof(float);  /* vertex size */
 379       vbuffer.buffer_offset = 0;
 380       pipe->set_vertex_buffers(pipe, 1, &vbuffer);
 381
 382       /* draw */
 383       util_draw_arrays(pipe, prim, 0, num_verts);
 384
 385       cso_restore_vertex_elements($self->cso);
 386
 387 error2:
 388       pipe_resource_reference(&vbuf, NULL);
 389 error1:
 390       ;
 391    }
 392
 393    void
 394    clear(unsigned buffers, const float *rgba, double depth = 0.0f,
 395          unsigned stencil = 0)
 396    {
 397       $self->pipe->clear($self->pipe, buffers, rgba, depth, stencil);
 398    }
 399
 400    void
 401    flush(unsigned flags = 0) {
 402       struct pipe_fence_handle *fence = NULL;
 403       $self->pipe->flush($self->pipe, &fence);
 404       if(fence) {
 405          /* TODO: allow asynchronous operation */
 406          $self->pipe->screen->fence_finish( $self->pipe->screen, fence, PIPE_TIMEOUT_INFINITE );
 407          $self->pipe->screen->fence_reference( $self->pipe->screen, &fence, NULL );
 408       }
 409    }
 410
 411    /*
 412     * Surface functions
 413     */
 414
 415    void resource_copy_region(struct pipe_resource *dst,
 416                              unsigned dst_level,
 417                              unsigned dstx, unsigned dsty, unsigned dstz,
 418                              struct pipe_resource *src,
 419                              unsigned src_level,
 420                              const struct pipe_box *src_box)
 421    {
 422       $self->pipe->resource_copy_region($self->pipe,
 423                                         dst, dst_level, dstx, dsty, dstz,
 424                                         src, src_level, src_box);
 425    }
 426
 427
 428    void clear_render_target(struct st_surface *dst,
 429                             float *rgba,
 430                             unsigned x, unsigned y,
 431                             unsigned width, unsigned height)
 432    {
 433       struct pipe_surface *_dst = NULL;
 434
 435      _dst = st_pipe_surface($self->pipe, dst, PIPE_BIND_RENDER_TARGET);
 436       if(!_dst)
 437          SWIG_exception(SWIG_ValueError, "couldn't acquire destination surface for writing");
 438
 439       $self->pipe->clear_render_target($self->pipe, _dst, rgba, x, y, width, height);
 440
 441    fail:
 442       pipe_surface_reference(&_dst, NULL);
 443    }
 444
 445    void clear_depth_stencil(struct st_surface *dst,
 446                             unsigned clear_flags,
 447                             double depth,
 448                             unsigned stencil,
 449                             unsigned x, unsigned y,
 450                             unsigned width, unsigned height)
 451    {
 452       struct pipe_surface *_dst = NULL;
 453
 454      _dst = st_pipe_surface($self->pipe, dst, PIPE_BIND_DEPTH_STENCIL);
 455       if(!_dst)
 456          SWIG_exception(SWIG_ValueError, "couldn't acquire destination surface for writing");
 457
 458       $self->pipe->clear_depth_stencil($self->pipe, _dst, clear_flags, depth, stencil,
 459                                        x, y, width, height);
 460
 461    fail:
 462       pipe_surface_reference(&_dst, NULL);
 463    }
 464
 465    %cstring_output_allocate_size(char **STRING, int *LENGTH, free(*$1));
 466    void
 467    surface_read_raw(struct st_surface *surface,
 468                     unsigned x, unsigned y, unsigned w, unsigned h,
 469                     char **STRING, int *LENGTH)
 470    {
 471       struct pipe_resource *texture = surface->texture;
 472       struct pipe_context *pipe = $self->pipe;
 473       struct pipe_transfer *transfer;
 474       unsigned stride;
 475
 476       stride = util_format_get_stride(texture->format, w);
 477       *LENGTH = util_format_get_nblocksy(texture->format, h) * stride;
 478       *STRING = (char *) malloc(*LENGTH);
 479       if(!*STRING)
 480          return;
 481
 482       transfer = pipe_get_transfer(pipe,
 483                                    surface->texture,
 484                                    surface->level,
 485                                    surface->layer,
 486                                    PIPE_TRANSFER_READ,
 487                                    x, y, w, h);
 488       if(transfer) {
 489          pipe_get_tile_raw(pipe, transfer, 0, 0, w, h, *STRING, stride);
 490          pipe->transfer_destroy(pipe, transfer);
 491       }
 492    }
 493
 494    %cstring_input_binary(const char *STRING, unsigned LENGTH);
 495    void
 496    surface_write_raw(struct st_surface *surface,
 497                      unsigned x, unsigned y, unsigned w, unsigned h,
 498                      const char *STRING, unsigned LENGTH, unsigned stride = 0)
 499    {
 500       struct pipe_resource *texture = surface->texture;
 501       struct pipe_context *pipe = $self->pipe;
 502       struct pipe_transfer *transfer;
 503
 504       if(stride == 0)
 505          stride = util_format_get_stride(texture->format, w);
 506
 507       if(LENGTH < util_format_get_nblocksy(texture->format, h) * stride)
 508          SWIG_exception(SWIG_ValueError, "offset must be smaller than buffer size");
 509
 510       transfer = pipe_get_transfer(pipe,
 511                                    surface->texture,
 512                                    surface->level,
 513                                    surface->layer,
 514                                    PIPE_TRANSFER_WRITE,
 515                                    x, y, w, h);
 516       if(!transfer)
 517          SWIG_exception(SWIG_MemoryError, "couldn't initiate transfer");
 518
 519       pipe_put_tile_raw(pipe, transfer, 0, 0, w, h, STRING, stride);
 520       pipe->transfer_destroy(pipe, transfer);
 521
 522    fail:
 523       return;
 524    }
 525
 526    void
 527    surface_read_rgba(struct st_surface *surface,
 528                      unsigned x, unsigned y, unsigned w, unsigned h,
 529                      float *rgba)
 530    {
 531       struct pipe_context *pipe = $self->pipe;
 532       struct pipe_transfer *transfer;
 533       transfer = pipe_get_transfer(pipe,
 534                                    surface->texture,
 535                                    surface->level,
 536                                    surface->layer,
 537                                    PIPE_TRANSFER_READ,
 538                                    x, y, w, h);
 539       if(transfer) {
 540          pipe_get_tile_rgba(pipe, transfer, 0, 0, w, h, rgba);
 541          pipe->transfer_destroy(pipe, transfer);
 542       }
 543    }
 544
 545    void
 546    surface_write_rgba(struct st_surface *surface,
 547                       unsigned x, unsigned y, unsigned w, unsigned h,
 548                       const float *rgba)
 549    {
 550       struct pipe_context *pipe = $self->pipe;
 551       struct pipe_transfer *transfer;
 552       transfer = pipe_get_transfer(pipe,
 553                                    surface->texture,
 554                                    surface->level,
 555                                    surface->layer,
 556                                    PIPE_TRANSFER_WRITE,
 557                                    x, y, w, h);
 558       if(transfer) {
 559          pipe_put_tile_rgba(pipe, transfer, 0, 0, w, h, rgba);
 560          pipe->transfer_destroy(pipe, transfer);
 561       }
 562    }
 563
 564    %cstring_output_allocate_size(char **STRING, int *LENGTH, free(*$1));
 565    void
 566    surface_read_rgba8(struct st_surface *surface,
 567                       unsigned x, unsigned y, unsigned w, unsigned h,
 568                       char **STRING, int *LENGTH)
 569    {
 570       struct pipe_context *pipe = $self->pipe;
 571       struct pipe_transfer *transfer;
 572       float *rgba;
 573       unsigned char *rgba8;
 574       unsigned i, j, k;
 575
 576       *LENGTH = 0;
 577       *STRING = NULL;
 578
 579       if (!surface)
 580          return;
 581
 582       *LENGTH = h*w*4;
 583       *STRING = (char *) malloc(*LENGTH);
 584       if(!*STRING)
 585          return;
 586
 587       rgba = malloc(h*w*4*sizeof(float));
 588       if(!rgba)
 589          return;
 590
 591       rgba8 = (unsigned char *) *STRING;
 592
 593       transfer = pipe_get_transfer(pipe,
 594                                    surface->texture,
 595                                    surface->level,
 596                                    surface->layer,
 597                                    PIPE_TRANSFER_READ,
 598                                    x, y, w, h);
 599       if(transfer) {
 600          pipe_get_tile_rgba(pipe, transfer, 0, 0, w, h, rgba);
 601          for(j = 0; j < h; ++j) {
 602             for(i = 0; i < w; ++i)
 603                for(k = 0; k <4; ++k)
 604                   rgba8[j*w*4 + i*4 + k] = float_to_ubyte(rgba[j*w*4 + i*4 + k]);
 605          }
 606          pipe->transfer_destroy(pipe, transfer);
 607       }
 608
 609       free(rgba);
 610    }
 611
 612    void
 613    surface_read_z(struct st_surface *surface,
 614                   unsigned x, unsigned y, unsigned w, unsigned h,
 615                   unsigned *z)
 616    {
 617       struct pipe_context *pipe = $self->pipe;
 618       struct pipe_transfer *transfer;
 619       transfer = pipe_get_transfer(pipe,
 620                                    surface->texture,
 621                                    surface->level,
 622                                    surface->layer,
 623                                    PIPE_TRANSFER_READ,
 624                                    x, y, w, h);
 625       if(transfer) {
 626          pipe_get_tile_z(pipe, transfer, 0, 0, w, h, z);
 627          pipe->transfer_destroy(pipe, transfer);
 628       }
 629    }
 630
 631    void
 632    surface_write_z(struct st_surface *surface,
 633                    unsigned x, unsigned y, unsigned w, unsigned h,
 634                    const unsigned *z)
 635    {
 636       struct pipe_context *pipe = $self->pipe;
 637       struct pipe_transfer *transfer;
 638       transfer = pipe_get_transfer(pipe,
 639                                    surface->texture,
 640                                    surface->level,
 641                                    surface->layer,
 642                                    PIPE_TRANSFER_WRITE,
 643                                    x, y, w, h);
 644       if(transfer) {
 645          pipe_put_tile_z(pipe, transfer, 0, 0, w, h, z);
 646          pipe->transfer_destroy(pipe, transfer);
 647       }
 648    }
 649
 650    void
 651    surface_sample_rgba(struct st_surface *surface,
 652                        float *rgba,
 653                        int norm = 0)
 654    {
 655       st_sample_surface($self->pipe, surface, rgba, norm != 0);
 656    }
 657
 658    unsigned
 659    surface_compare_rgba(struct st_surface *surface,
 660                         unsigned x, unsigned y, unsigned w, unsigned h,
 661                         const float *rgba, float tol = 0.0)
 662    {
 663       struct pipe_context *pipe = $self->pipe;
 664       struct pipe_transfer *transfer;
 665       float *rgba2;
 666       const float *p1;
 667       const float *p2;
 668       unsigned i, j, n;
 669
 670       rgba2 = MALLOC(h*w*4*sizeof(float));
 671       if(!rgba2)
 672          return ~0;
 673
 674       transfer = pipe_get_transfer(pipe,
 675                                    surface->texture,
 676                                    surface->level,
 677                                    surface->layer,
 678                                    PIPE_TRANSFER_READ,
 679                                    x, y, w, h);
 680       if(!transfer) {
 681          FREE(rgba2);
 682          return ~0;
 683       }
 684
 685       pipe_get_tile_rgba(pipe, transfer, 0, 0, w, h, rgba2);
 686       pipe->transfer_destroy(pipe, transfer);
 687
 688       p1 = rgba;
 689       p2 = rgba2;
 690       n = 0;
 691       for(i = h*w; i; --i) {
 692          unsigned differs = 0;
 693          for(j = 4; j; --j) {
 694             float delta = *p2++ - *p1++;
 695             if (delta < -tol || delta > tol)
 696                 differs = 1;
 697          }
 698          n += differs;
 699       }
 700
 701       FREE(rgba2);
 702
 703       return n;
 704    }
 705
 706    %cstring_input_binary(const char *STRING, unsigned LENGTH);
 707    void
 708    transfer_inline_write(struct pipe_resource *resource,
 709                          unsigned level,
 710                          unsigned usage,
 711                          const struct pipe_box *box,
 712                          const char *STRING, unsigned LENGTH,
 713                          unsigned stride,
 714                          unsigned layer_stride)
 715    {
 716       struct pipe_context *pipe = $self->pipe;
 717
 718       pipe->transfer_inline_write(pipe, resource, level, usage, box, STRING, stride, layer_stride);
 719    }
 720
 721    %cstring_output_allocate_size(char **STRING, int *LENGTH, free(*$1));
 722    void buffer_read(struct pipe_resource *buffer,
 723                     char **STRING, int *LENGTH)
 724    {
 725       struct pipe_context *pipe = $self->pipe;
 726
 727       assert(buffer->target == PIPE_BUFFER);
 728
 729       *LENGTH = buffer->width0;
 730       *STRING = (char *) malloc(buffer->width0);
 731       if(!*STRING)
 732          return;
 733
 734       pipe_buffer_read(pipe, buffer, 0, buffer->width0, *STRING);
 735    }
 736
 737    void buffer_write(struct pipe_resource *buffer,
 738                      const char *STRING, unsigned LENGTH, unsigned offset = 0)
 739    {
 740       struct pipe_context *pipe = $self->pipe;
 741
 742       assert(buffer->target == PIPE_BUFFER);
 743
 744       if(offset > buffer->width0)
 745          SWIG_exception(SWIG_ValueError, "offset must be smaller than buffer size");
 746
 747       if(offset + LENGTH > buffer->width0)
 748          SWIG_exception(SWIG_ValueError, "data length must fit inside the buffer");
 749
 750       pipe_buffer_write(pipe, buffer, offset, LENGTH, STRING);
 751
 752 fail:
 753       return;
 754    }
 755
 756 };