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 swizzle_r = 0,
 136                        unsigned swizzle_g = 1,
 137                        unsigned swizzle_b = 2,
 138                        unsigned swizzle_a = 3)
 139    {
 140       struct pipe_context *pipe = $self->pipe;
 141       struct pipe_sampler_view templat;
 142
 143       memset(&templat, 0, sizeof templat);
 144       if (format == PIPE_FORMAT_NONE) {
 145          templat.format = texture->format;
 146       } else {
 147          templat.format = format;
 148       }
 149       templat.last_level = MIN2(last_level, texture->last_level);
 150       templat.first_level = first_level;
 151       templat.last_level = last_level;
 152       templat.swizzle_r = swizzle_r;
 153       templat.swizzle_g = swizzle_g;
 154       templat.swizzle_b = swizzle_b;
 155       templat.swizzle_a = swizzle_a;
 156
 157       return pipe->create_sampler_view(pipe, texture, &templat);
 158    }
 159
 160    void
 161    sampler_view_destroy(struct pipe_context *ctx,
 162                         struct pipe_sampler_view *view)
 163    {
 164       struct pipe_context *pipe = $self->pipe;
 165
 166       pipe->sampler_view_destroy(pipe, view);
 167    }
 168
 169    /*
 170     * Parameter-like state (or properties)
 171     */
 172
 173    void set_blend_color(const struct pipe_blend_color *state ) {
 174       cso_set_blend_color($self->cso, state);
 175    }
 176
 177    void set_stencil_ref(const struct pipe_stencil_ref *state ) {
 178       cso_set_stencil_ref($self->cso, state);
 179    }
 180
 181    void set_clip(const struct pipe_clip_state *state ) {
 182       $self->pipe->set_clip_state($self->pipe, state);
 183    }
 184
 185    void set_constant_buffer(unsigned shader, unsigned index,
 186                             struct pipe_resource *buffer )
 187    {
 188       $self->pipe->set_constant_buffer($self->pipe, shader, index, buffer);
 189    }
 190
 191    void set_framebuffer(const struct pipe_framebuffer_state *state )
 192    {
 193       memcpy(&$self->framebuffer, state, sizeof *state);
 194       cso_set_framebuffer($self->cso, state);
 195    }
 196
 197    void set_polygon_stipple(const struct pipe_poly_stipple *state ) {
 198       $self->pipe->set_polygon_stipple($self->pipe, state);
 199    }
 200
 201    void set_scissor(const struct pipe_scissor_state *state ) {
 202       $self->pipe->set_scissor_state($self->pipe, state);
 203    }
 204
 205    void set_viewport(const struct pipe_viewport_state *state) {
 206       cso_set_viewport($self->cso, state);
 207    }
 208
 209    void set_fragment_sampler_view(unsigned index,
 210                                   struct pipe_sampler_view *view)
 211    {
 212       pipe_sampler_view_reference(&$self->fragment_sampler_views[index], view);
 213
 214       $self->pipe->set_fragment_sampler_views($self->pipe,
 215                                               PIPE_MAX_SAMPLERS,
 216                                               $self->fragment_sampler_views);
 217    }
 218
 219    void set_vertex_sampler_view(unsigned index,
 220                                 struct pipe_sampler_view *view)
 221    {
 222       pipe_sampler_view_reference(&$self->vertex_sampler_views[index], view);
 223
 224       $self->pipe->set_vertex_sampler_views($self->pipe,
 225                                             PIPE_MAX_VERTEX_SAMPLERS,
 226                                             $self->vertex_sampler_views);
 227    }
 228
 229    void set_fragment_sampler_texture(unsigned index,
 230                                      struct pipe_resource *texture) {
 231       struct pipe_sampler_view templ;
 232
 233       if(!texture)
 234          texture = $self->default_texture;
 235       pipe_sampler_view_reference(&$self->fragment_sampler_views[index], NULL);
 236       u_sampler_view_default_template(&templ,
 237                                       texture,
 238                                       texture->format);
 239       $self->fragment_sampler_views[index] = $self->pipe->create_sampler_view($self->pipe,
 240                                                                               texture,
 241                                                                               &templ);
 242       $self->pipe->set_fragment_sampler_views($self->pipe,
 243                                               PIPE_MAX_SAMPLERS,
 244                                               $self->fragment_sampler_views);
 245    }
 246
 247    void set_vertex_sampler_texture(unsigned index,
 248                                    struct pipe_resource *texture) {
 249       struct pipe_sampler_view templ;
 250
 251       if(!texture)
 252          texture = $self->default_texture;
 253       pipe_sampler_view_reference(&$self->vertex_sampler_views[index], NULL);
 254       u_sampler_view_default_template(&templ,
 255                                       texture,
 256                                       texture->format);
 257       $self->vertex_sampler_views[index] = $self->pipe->create_sampler_view($self->pipe,
 258                                                                             texture,
 259                                                                             &templ);
 260
 261       $self->pipe->set_vertex_sampler_views($self->pipe,
 262                                             PIPE_MAX_VERTEX_SAMPLERS,
 263                                             $self->vertex_sampler_views);
 264    }
 265
 266    void set_vertex_buffer(unsigned index,
 267                           unsigned stride,
 268                           unsigned max_index,
 269                           unsigned buffer_offset,
 270                           struct pipe_resource *buffer)
 271    {
 272       unsigned i;
 273       struct pipe_vertex_buffer state;
 274
 275       memset(&state, 0, sizeof(state));
 276       state.stride = stride;
 277       state.max_index = max_index;
 278       state.buffer_offset = buffer_offset;
 279       state.buffer = buffer;
 280
 281       memcpy(&$self->vertex_buffers[index], &state, sizeof(state));
 282
 283       for(i = 0; i < PIPE_MAX_ATTRIBS; ++i)
 284          if(self->vertex_buffers[i].buffer)
 285             $self->num_vertex_buffers = i + 1;
 286
 287       $self->pipe->set_vertex_buffers($self->pipe,
 288                                       $self->num_vertex_buffers,
 289                                       $self->vertex_buffers);
 290    }
 291
 292    void set_vertex_element(unsigned index,
 293                            const struct pipe_vertex_element *element)
 294    {
 295       memcpy(&$self->vertex_elements[index], element, sizeof(*element));
 296    }
 297
 298    void set_vertex_elements(unsigned num)
 299    {
 300       $self->num_vertex_elements = num;
 301       cso_set_vertex_elements($self->cso,
 302                               $self->num_vertex_elements,
 303                               $self->vertex_elements);
 304    }
 305
 306    /*
 307     * Draw functions
 308     */
 309
 310    void draw_arrays(unsigned mode, unsigned start, unsigned count) {
 311       $self->pipe->draw_arrays($self->pipe, mode, start, count);
 312    }
 313
 314    void draw_elements( struct pipe_resource *indexBuffer,
 315                        unsigned indexSize, int indexBias,
 316                        unsigned mode, unsigned start, unsigned count)
 317    {
 318       $self->pipe->draw_elements($self->pipe,
 319                                  indexBuffer,
 320                                  indexSize,
 321                                  indexBias,
 322                                  mode, start, count);
 323    }
 324
 325    void draw_range_elements( struct pipe_resource *indexBuffer,
 326                              unsigned indexSize, int indexBias,
 327                              unsigned minIndex, unsigned maxIndex,
 328                              unsigned mode, unsigned start, unsigned count)
 329    {
 330       $self->pipe->draw_range_elements($self->pipe,
 331                                        indexBuffer, indexSize, indexBias,
 332                                        minIndex, maxIndex,
 333                                        mode, start, count);
 334    }
 335
 336    void draw_vertices(unsigned prim,
 337                       unsigned num_verts,
 338                       unsigned num_attribs,
 339                       const float *vertices)
 340    {
 341       struct pipe_context *pipe = $self->pipe;
 342       struct pipe_screen *screen = pipe->screen;
 343       struct pipe_resource *vbuf;
 344       struct pipe_transfer *transfer;
 345       struct pipe_vertex_element velements[PIPE_MAX_ATTRIBS];
 346       struct pipe_vertex_buffer vbuffer;
 347       float *map;
 348       unsigned size;
 349       unsigned i;
 350
 351       size = num_verts * num_attribs * 4 * sizeof(float);
 352
 353       vbuf = pipe_buffer_create(screen,
 354                                 PIPE_BIND_VERTEX_BUFFER,
 355                                 size);
 356       if(!vbuf)
 357          goto error1;
 358
 359       map = pipe_buffer_map(pipe, vbuf, PIPE_TRANSFER_WRITE, &transfer);
 360       if (!map)
 361          goto error2;
 362       memcpy(map, vertices, size);
 363       pipe_buffer_unmap(pipe, vbuf, transfer);
 364
 365       cso_save_vertex_elements($self->cso);
 366
 367       /* tell pipe about the vertex attributes */
 368       for (i = 0; i < num_attribs; i++) {
 369          velements[i].src_offset = i * 4 * sizeof(float);
 370          velements[i].instance_divisor = 0;
 371          velements[i].vertex_buffer_index = 0;
 372          velements[i].src_format = PIPE_FORMAT_R32G32B32A32_FLOAT;
 373       }
 374       cso_set_vertex_elements($self->cso, num_attribs, velements);
 375
 376       /* tell pipe about the vertex buffer */
 377       memset(&vbuffer, 0, sizeof(vbuffer));
 378       vbuffer.buffer = vbuf;
 379       vbuffer.stride = num_attribs * 4 * sizeof(float);  /* vertex size */
 380       vbuffer.buffer_offset = 0;
 381       vbuffer.max_index = num_verts - 1;
 382       pipe->set_vertex_buffers(pipe, 1, &vbuffer);
 383
 384       /* draw */
 385       pipe->draw_arrays(pipe, prim, 0, num_verts);
 386
 387       cso_restore_vertex_elements($self->cso);
 388
 389 error2:
 390       pipe_resource_reference(&vbuf, NULL);
 391 error1:
 392       ;
 393    }
 394
 395    void
 396    clear(unsigned buffers, const float *rgba, double depth = 0.0f,
 397          unsigned stencil = 0)
 398    {
 399       $self->pipe->clear($self->pipe, buffers, rgba, depth, stencil);
 400    }
 401
 402    void
 403    flush(unsigned flags = 0) {
 404       struct pipe_fence_handle *fence = NULL;
 405       $self->pipe->flush($self->pipe, flags | PIPE_FLUSH_RENDER_CACHE, &fence);
 406       if(fence) {
 407          /* TODO: allow asynchronous operation */
 408          $self->pipe->screen->fence_finish( $self->pipe->screen, fence, 0 );
 409          $self->pipe->screen->fence_reference( $self->pipe->screen, &fence, NULL );
 410       }
 411    }
 412
 413    /*
 414     * Surface functions
 415     */
 416
 417    void resource_copy_region(struct pipe_resource *dst,
 418                              struct pipe_subresource subdst,
 419                              unsigned dstx, unsigned dsty, unsigned dstz,
 420                              struct pipe_resource *src,
 421                              struct pipe_subresource subsrc,
 422                              unsigned srcx, unsigned srcy, unsigned srcz,
 423                              unsigned width, unsigned height)
 424    {
 425       $self->pipe->resource_copy_region($self->pipe,
 426                                         dst, subdst, dstx, dsty, dstz,
 427                                         src, subsrc, srcx, srcy, srcz,
 428                                         width, height);
 429    }
 430
 431    void resource_fill_region(struct pipe_resource *dst,
 432                              struct pipe_subresource subdst,
 433                              unsigned dstx, unsigned dsty, unsigned dstz,
 434                              unsigned width, unsigned height,
 435                              unsigned value)
 436    {
 437       $self->pipe->resource_fill_region($self->pipe,
 438                                         dst, subdst, dstx, dsty, dstz,
 439                                         width, height, value);
 440    }
 441
 442    %cstring_output_allocate_size(char **STRING, int *LENGTH, free(*$1));
 443    void
 444    surface_read_raw(struct st_surface *surface,
 445                     unsigned x, unsigned y, unsigned w, unsigned h,
 446                     char **STRING, int *LENGTH)
 447    {
 448       struct pipe_resource *texture = surface->texture;
 449       struct pipe_context *pipe = $self->pipe;
 450       struct pipe_transfer *transfer;
 451       unsigned stride;
 452
 453       stride = util_format_get_stride(texture->format, w);
 454       *LENGTH = util_format_get_nblocksy(texture->format, h) * stride;
 455       *STRING = (char *) malloc(*LENGTH);
 456       if(!*STRING)
 457          return;
 458
 459       transfer = pipe_get_transfer(pipe,
 460                                    surface->texture,
 461                                    surface->face,
 462                                    surface->level,
 463                                    surface->zslice,
 464                                    PIPE_TRANSFER_READ,
 465                                    x, y, w, h);
 466       if(transfer) {
 467          pipe_get_tile_raw(pipe, transfer, 0, 0, w, h, *STRING, stride);
 468          pipe->transfer_destroy(pipe, transfer);
 469       }
 470    }
 471
 472    %cstring_input_binary(const char *STRING, unsigned LENGTH);
 473    void
 474    surface_write_raw(struct st_surface *surface,
 475                      unsigned x, unsigned y, unsigned w, unsigned h,
 476                      const char *STRING, unsigned LENGTH, unsigned stride = 0)
 477    {
 478       struct pipe_resource *texture = surface->texture;
 479       struct pipe_context *pipe = $self->pipe;
 480       struct pipe_transfer *transfer;
 481
 482       if(stride == 0)
 483          stride = util_format_get_stride(texture->format, w);
 484
 485       if(LENGTH < util_format_get_nblocksy(texture->format, h) * stride)
 486          SWIG_exception(SWIG_ValueError, "offset must be smaller than buffer size");
 487
 488       transfer = pipe_get_transfer(pipe,
 489                                    surface->texture,
 490                                    surface->face,
 491                                    surface->level,
 492                                    surface->zslice,
 493                                    PIPE_TRANSFER_WRITE,
 494                                    x, y, w, h);
 495       if(!transfer)
 496          SWIG_exception(SWIG_MemoryError, "couldn't initiate transfer");
 497
 498       pipe_put_tile_raw(pipe, transfer, 0, 0, w, h, STRING, stride);
 499       pipe->transfer_destroy(pipe, transfer);
 500
 501    fail:
 502       return;
 503    }
 504
 505    void
 506    surface_read_rgba(struct st_surface *surface,
 507                      unsigned x, unsigned y, unsigned w, unsigned h,
 508                      float *rgba)
 509    {
 510       struct pipe_context *pipe = $self->pipe;
 511       struct pipe_transfer *transfer;
 512       transfer = pipe_get_transfer(pipe,
 513                                    surface->texture,
 514                                    surface->face,
 515                                    surface->level,
 516                                    surface->zslice,
 517                                    PIPE_TRANSFER_READ,
 518                                    x, y, w, h);
 519       if(transfer) {
 520          pipe_get_tile_rgba(pipe, transfer, 0, 0, w, h, rgba);
 521          pipe->transfer_destroy(pipe, transfer);
 522       }
 523    }
 524
 525    void
 526    surface_write_rgba(struct st_surface *surface,
 527                       unsigned x, unsigned y, unsigned w, unsigned h,
 528                       const float *rgba)
 529    {
 530       struct pipe_context *pipe = $self->pipe;
 531       struct pipe_transfer *transfer;
 532       transfer = pipe_get_transfer(pipe,
 533                                    surface->texture,
 534                                    surface->face,
 535                                    surface->level,
 536                                    surface->zslice,
 537                                    PIPE_TRANSFER_WRITE,
 538                                    x, y, w, h);
 539       if(transfer) {
 540          pipe_put_tile_rgba(pipe, transfer, 0, 0, w, h, rgba);
 541          pipe->transfer_destroy(pipe, transfer);
 542       }
 543    }
 544
 545    %cstring_output_allocate_size(char **STRING, int *LENGTH, free(*$1));
 546    void
 547    surface_read_rgba8(struct st_surface *surface,
 548                       unsigned x, unsigned y, unsigned w, unsigned h,
 549                       char **STRING, int *LENGTH)
 550    {
 551       struct pipe_context *pipe = $self->pipe;
 552       struct pipe_transfer *transfer;
 553       float *rgba;
 554       unsigned char *rgba8;
 555       unsigned i, j, k;
 556
 557       *LENGTH = 0;
 558       *STRING = NULL;
 559
 560       if (!surface)
 561          return;
 562
 563       *LENGTH = h*w*4;
 564       *STRING = (char *) malloc(*LENGTH);
 565       if(!*STRING)
 566          return;
 567
 568       rgba = malloc(h*w*4*sizeof(float));
 569       if(!rgba)
 570          return;
 571
 572       rgba8 = (unsigned char *) *STRING;
 573
 574       transfer = pipe_get_transfer(pipe,
 575                                    surface->texture,
 576                                    surface->face,
 577                                    surface->level,
 578                                    surface->zslice,
 579                                    PIPE_TRANSFER_READ,
 580                                    x, y, w, h);
 581       if(transfer) {
 582          pipe_get_tile_rgba(pipe, transfer, 0, 0, w, h, rgba);
 583          for(j = 0; j < h; ++j) {
 584             for(i = 0; i < w; ++i)
 585                for(k = 0; k <4; ++k)
 586                   rgba8[j*w*4 + i*4 + k] = float_to_ubyte(rgba[j*w*4 + i*4 + k]);
 587          }
 588          pipe->transfer_destroy(pipe, transfer);
 589       }
 590
 591       free(rgba);
 592    }
 593
 594    void
 595    surface_read_z(struct st_surface *surface,
 596                   unsigned x, unsigned y, unsigned w, unsigned h,
 597                   unsigned *z)
 598    {
 599       struct pipe_context *pipe = $self->pipe;
 600       struct pipe_transfer *transfer;
 601       transfer = pipe_get_transfer(pipe,
 602                                    surface->texture,
 603                                    surface->face,
 604                                    surface->level,
 605                                    surface->zslice,
 606                                    PIPE_TRANSFER_READ,
 607                                    x, y, w, h);
 608       if(transfer) {
 609          pipe_get_tile_z(pipe, transfer, 0, 0, w, h, z);
 610          pipe->transfer_destroy(pipe, transfer);
 611       }
 612    }
 613
 614    void
 615    surface_write_z(struct st_surface *surface,
 616                    unsigned x, unsigned y, unsigned w, unsigned h,
 617                    const unsigned *z)
 618    {
 619       struct pipe_context *pipe = $self->pipe;
 620       struct pipe_transfer *transfer;
 621       transfer = pipe_get_transfer(pipe,
 622                                    surface->texture,
 623                                    surface->face,
 624                                    surface->level,
 625                                    surface->zslice,
 626                                    PIPE_TRANSFER_WRITE,
 627                                    x, y, w, h);
 628       if(transfer) {
 629          pipe_put_tile_z(pipe, transfer, 0, 0, w, h, z);
 630          pipe->transfer_destroy(pipe, transfer);
 631       }
 632    }
 633
 634    void
 635    surface_sample_rgba(struct st_surface *surface,
 636                        float *rgba,
 637                        int norm = 0)
 638    {
 639       st_sample_surface($self->pipe, surface, rgba, norm != 0);
 640    }
 641
 642    unsigned
 643    surface_compare_rgba(struct st_surface *surface,
 644                         unsigned x, unsigned y, unsigned w, unsigned h,
 645                         const float *rgba, float tol = 0.0)
 646    {
 647       struct pipe_context *pipe = $self->pipe;
 648       struct pipe_transfer *transfer;
 649       float *rgba2;
 650       const float *p1;
 651       const float *p2;
 652       unsigned i, j, n;
 653
 654       rgba2 = MALLOC(h*w*4*sizeof(float));
 655       if(!rgba2)
 656          return ~0;
 657
 658       transfer = pipe_get_transfer(pipe,
 659                                    surface->texture,
 660                                    surface->face,
 661                                    surface->level,
 662                                    surface->zslice,
 663                                    PIPE_TRANSFER_READ,
 664                                    x, y, w, h);
 665       if(!transfer) {
 666          FREE(rgba2);
 667          return ~0;
 668       }
 669
 670       pipe_get_tile_rgba(pipe, transfer, 0, 0, w, h, rgba2);
 671       pipe->transfer_destroy(pipe, transfer);
 672
 673       p1 = rgba;
 674       p2 = rgba2;
 675       n = 0;
 676       for(i = h*w; i; --i) {
 677          unsigned differs = 0;
 678          for(j = 4; j; --j) {
 679             float delta = *p2++ - *p1++;
 680             if (delta < -tol || delta > tol)
 681                 differs = 1;
 682          }
 683          n += differs;
 684       }
 685
 686       FREE(rgba2);
 687
 688       return n;
 689    }
 690
 691    %cstring_input_binary(const char *STRING, unsigned LENGTH);
 692    void
 693    transfer_inline_write(struct pipe_resource *resource,
 694                          struct pipe_subresource *sr,
 695                          unsigned usage,
 696                          const struct pipe_box *box,
 697                          const char *STRING, unsigned LENGTH,
 698                          unsigned stride,
 699                          unsigned slice_stride)
 700    {
 701       struct pipe_context *pipe = $self->pipe;
 702
 703       pipe->transfer_inline_write(pipe, resource, *sr, usage, box, STRING, stride, slice_stride);
 704    }
 705
 706    %cstring_output_allocate_size(char **STRING, int *LENGTH, free(*$1));
 707    void buffer_read(struct pipe_resource *buffer,
 708                     char **STRING, int *LENGTH)
 709    {
 710       struct pipe_context *pipe = $self->pipe;
 711
 712       assert(buffer->target == PIPE_BUFFER);
 713
 714       *LENGTH = buffer->width0;
 715       *STRING = (char *) malloc(buffer->width0);
 716       if(!*STRING)
 717          return;
 718
 719       pipe_buffer_read(pipe, buffer, 0, buffer->width0, *STRING);
 720    }
 721
 722    void buffer_write(struct pipe_resource *buffer,
 723                      const char *STRING, unsigned LENGTH, unsigned offset = 0)
 724    {
 725       struct pipe_context *pipe = $self->pipe;
 726
 727       assert(buffer->target == PIPE_BUFFER);
 728
 729       if(offset > buffer->width0)
 730          SWIG_exception(SWIG_ValueError, "offset must be smaller than buffer size");
 731
 732       if(offset + LENGTH > buffer->width0)
 733          SWIG_exception(SWIG_ValueError, "data length must fit inside the buffer");
 734
 735       pipe_buffer_write(pipe, buffer, offset, LENGTH, STRING);
 736
 737 fail:
 738       return;
 739    }
 740
 741 };