src/gallium/drivers/llvmpipe/lp_setup.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  * Tiling engine.
  30  *
  31  * Builds per-tile display lists and executes them on calls to
  32  * lp_setup_flush().
  33  */
  34
  35 #include "pipe/p_defines.h"
  36 #include "util/u_inlines.h"
  37 #include "util/u_memory.h"
  38 #include "util/u_pack_color.h"
  39 #include "util/u_surface.h"
  40 #include "lp_scene.h"
  41 #include "lp_scene_queue.h"
  42 #include "lp_buffer.h"
  43 #include "lp_texture.h"
  44 #include "lp_debug.h"
  45 #include "lp_fence.h"
  46 #include "lp_rast.h"
  47 #include "lp_setup_context.h"
  48 #include "lp_screen.h"
  49 #include "lp_winsys.h"
  50
  51 #include "draw/draw_context.h"
  52 #include "draw/draw_vbuf.h"
  53
  54
  55 static void set_scene_state( struct setup_context *, unsigned );
  56
  57
  58 struct lp_scene *
  59 lp_setup_get_current_scene(struct setup_context *setup)
  60 {
  61    if (!setup->scene) {
  62
  63       /* wait for a free/empty scene
  64        */
  65       setup->scene = lp_scene_dequeue(setup->empty_scenes, TRUE);
  66
  67       if(0)lp_scene_reset( setup->scene ); /* XXX temporary? */
  68
  69       lp_scene_set_framebuffer_size(setup->scene,
  70                                     setup->fb.width,
  71                                     setup->fb.height);
  72    }
  73    return setup->scene;
  74 }
  75
  76
  77 static void
  78 first_triangle( struct setup_context *setup,
  79                 const float (*v0)[4],
  80                 const float (*v1)[4],
  81                 const float (*v2)[4])
  82 {
  83    set_scene_state( setup, SETUP_ACTIVE );
  84    lp_setup_choose_triangle( setup );
  85    setup->triangle( setup, v0, v1, v2 );
  86 }
  87
  88 static void
  89 first_line( struct setup_context *setup,
  90             const float (*v0)[4],
  91             const float (*v1)[4])
  92 {
  93    set_scene_state( setup, SETUP_ACTIVE );
  94    lp_setup_choose_line( setup );
  95    setup->line( setup, v0, v1 );
  96 }
  97
  98 static void
  99 first_point( struct setup_context *setup,
 100              const float (*v0)[4])
 101 {
 102    set_scene_state( setup, SETUP_ACTIVE );
 103    lp_setup_choose_point( setup );
 104    setup->point( setup, v0 );
 105 }
 106
 107 static void reset_context( struct setup_context *setup )
 108 {
 109    LP_DBG(DEBUG_SETUP, "%s\n", __FUNCTION__);
 110
 111    /* Reset derived state */
 112    setup->constants.stored_size = 0;
 113    setup->constants.stored_data = NULL;
 114    setup->fs.stored = NULL;
 115    setup->dirty = ~0;
 116
 117    /* no current bin */
 118    setup->scene = NULL;
 119
 120    /* Reset some state:
 121     */
 122    setup->clear.flags = 0;
 123
 124    /* Have an explicit "start-binning" call and get rid of this
 125     * pointer twiddling?
 126     */
 127    setup->line = first_line;
 128    setup->point = first_point;
 129    setup->triangle = first_triangle;
 130 }
 131
 132
 133 /** Rasterize all scene's bins */
 134 static void
 135 lp_setup_rasterize_scene( struct setup_context *setup,
 136                          boolean write_depth )
 137 {
 138    struct lp_scene *scene = lp_setup_get_current_scene(setup);
 139
 140    lp_rasterize_scene(setup->rast,
 141                       scene,
 142                       &setup->fb,
 143                       write_depth);
 144
 145    reset_context( setup );
 146
 147    LP_DBG(DEBUG_SETUP, "%s done \n", __FUNCTION__);
 148 }
 149
 150
 151
 152 static void
 153 begin_binning( struct setup_context *setup )
 154 {
 155    struct lp_scene *scene = lp_setup_get_current_scene(setup);
 156
 157    LP_DBG(DEBUG_SETUP, "%s color: %s depth: %s\n", __FUNCTION__,
 158           (setup->clear.flags & PIPE_CLEAR_COLOR) ? "clear": "load",
 159           (setup->clear.flags & PIPE_CLEAR_DEPTHSTENCIL) ? "clear": "load");
 160
 161    if (setup->fb.nr_cbufs) {
 162       if (setup->clear.flags & PIPE_CLEAR_COLOR)
 163          lp_scene_bin_everywhere( scene,
 164                                   lp_rast_clear_color,
 165                                   setup->clear.color );
 166       else
 167          lp_scene_bin_everywhere( scene,
 168                                   lp_rast_load_color,
 169                                   lp_rast_arg_null() );
 170    }
 171
 172    if (setup->fb.zsbuf) {
 173       if (setup->clear.flags & PIPE_CLEAR_DEPTHSTENCIL)
 174          lp_scene_bin_everywhere( scene,
 175                                   lp_rast_clear_zstencil,
 176                                   setup->clear.zstencil );
 177    }
 178
 179    LP_DBG(DEBUG_SETUP, "%s done\n", __FUNCTION__);
 180 }
 181
 182
 183 /* This basically bins and then flushes any outstanding full-screen
 184  * clears.
 185  *
 186  * TODO: fast path for fullscreen clears and no triangles.
 187  */
 188 static void
 189 execute_clears( struct setup_context *setup )
 190 {
 191    LP_DBG(DEBUG_SETUP, "%s\n", __FUNCTION__);
 192
 193    begin_binning( setup );
 194    lp_setup_rasterize_scene( setup, TRUE );
 195 }
 196
 197
 198 static void
 199 set_scene_state( struct setup_context *setup,
 200            unsigned new_state )
 201 {
 202    unsigned old_state = setup->state;
 203
 204    if (old_state == new_state)
 205       return;
 206
 207    LP_DBG(DEBUG_SETUP, "%s old %d new %d\n", __FUNCTION__, old_state, new_state);
 208
 209    switch (new_state) {
 210    case SETUP_ACTIVE:
 211       begin_binning( setup );
 212       break;
 213
 214    case SETUP_CLEARED:
 215       if (old_state == SETUP_ACTIVE) {
 216          assert(0);
 217          return;
 218       }
 219       break;
 220
 221    case SETUP_FLUSHED:
 222       if (old_state == SETUP_CLEARED)
 223          execute_clears( setup );
 224       else
 225          lp_setup_rasterize_scene( setup, TRUE );
 226       break;
 227    }
 228
 229    setup->state = new_state;
 230 }
 231
 232
 233 void
 234 lp_setup_flush( struct setup_context *setup,
 235                 unsigned flags )
 236 {
 237    LP_DBG(DEBUG_SETUP, "%s\n", __FUNCTION__);
 238
 239    set_scene_state( setup, SETUP_FLUSHED );
 240 }
 241
 242
 243 void
 244 lp_setup_bind_framebuffer( struct setup_context *setup,
 245                            const struct pipe_framebuffer_state *fb )
 246 {
 247    struct lp_scene *scene = lp_setup_get_current_scene(setup);
 248
 249    LP_DBG(DEBUG_SETUP, "%s\n", __FUNCTION__);
 250
 251    set_scene_state( setup, SETUP_FLUSHED );
 252
 253    /* re-get scene pointer, may have a new scene after flushing */
 254    (void) scene;
 255    scene = lp_setup_get_current_scene(setup);
 256
 257    util_copy_framebuffer_state(&setup->fb, fb);
 258
 259    lp_scene_set_framebuffer_size(scene, setup->fb.width, setup->fb.height);
 260 }
 261
 262
 263 void
 264 lp_setup_clear( struct setup_context *setup,
 265                 const float *color,
 266                 double depth,
 267                 unsigned stencil,
 268                 unsigned flags )
 269 {
 270    struct lp_scene *scene = lp_setup_get_current_scene(setup);
 271    unsigned i;
 272
 273    LP_DBG(DEBUG_SETUP, "%s state %d\n", __FUNCTION__, setup->state);
 274
 275
 276    if (flags & PIPE_CLEAR_COLOR) {
 277       for (i = 0; i < 4; ++i)
 278          setup->clear.color.clear_color[i] = float_to_ubyte(color[i]);
 279    }
 280
 281    if (flags & PIPE_CLEAR_DEPTHSTENCIL) {
 282       setup->clear.zstencil.clear_zstencil =
 283          util_pack_z_stencil(setup->fb.zsbuf->format,
 284                              depth,
 285                              stencil);
 286    }
 287
 288    if (setup->state == SETUP_ACTIVE) {
 289       /* Add the clear to existing scene.  In the unusual case where
 290        * both color and depth-stencil are being cleared when there's
 291        * already been some rendering, we could discard the currently
 292        * binned scene and start again, but I don't see that as being
 293        * a common usage.
 294        */
 295       if (flags & PIPE_CLEAR_COLOR)
 296          lp_scene_bin_everywhere( scene,
 297                                   lp_rast_clear_color,
 298                                   setup->clear.color );
 299
 300       if (setup->clear.flags & PIPE_CLEAR_DEPTHSTENCIL)
 301          lp_scene_bin_everywhere( scene,
 302                                   lp_rast_clear_zstencil,
 303                                   setup->clear.zstencil );
 304    }
 305    else {
 306       /* Put ourselves into the 'pre-clear' state, specifically to try
 307        * and accumulate multiple clears to color and depth_stencil
 308        * buffers which the app or state-tracker might issue
 309        * separately.
 310        */
 311       set_scene_state( setup, SETUP_CLEARED );
 312
 313       setup->clear.flags |= flags;
 314    }
 315 }
 316
 317
 318 /**
 319  * Emit a fence.
 320  */
 321 struct pipe_fence_handle *
 322 lp_setup_fence( struct setup_context *setup )
 323 {
 324    struct lp_scene *scene = lp_setup_get_current_scene(setup);
 325    const unsigned rank = lp_scene_get_num_bins( scene ); /* xxx */
 326    struct lp_fence *fence = lp_fence_create(rank);
 327
 328    LP_DBG(DEBUG_SETUP, "%s rank %u\n", __FUNCTION__, rank);
 329
 330    set_scene_state( setup, SETUP_ACTIVE );
 331
 332    /* insert the fence into all command bins */
 333    lp_scene_bin_everywhere( scene,
 334                             lp_rast_fence,
 335                             lp_rast_arg_fence(fence) );
 336
 337    return (struct pipe_fence_handle *) fence;
 338 }
 339
 340
 341 void
 342 lp_setup_set_triangle_state( struct setup_context *setup,
 343                              unsigned cull_mode,
 344                              boolean ccw_is_frontface,
 345                              boolean scissor )
 346 {
 347    LP_DBG(DEBUG_SETUP, "%s\n", __FUNCTION__);
 348
 349    setup->ccw_is_frontface = ccw_is_frontface;
 350    setup->cullmode = cull_mode;
 351    setup->triangle = first_triangle;
 352    setup->scissor_test = scissor;
 353 }
 354
 355
 356
 357 void
 358 lp_setup_set_fs_inputs( struct setup_context *setup,
 359                         const struct lp_shader_input *input,
 360                         unsigned nr )
 361 {
 362    LP_DBG(DEBUG_SETUP, "%s %p %u\n", __FUNCTION__, (void *) input, nr);
 363
 364    memcpy( setup->fs.input, input, nr * sizeof input[0] );
 365    setup->fs.nr_inputs = nr;
 366 }
 367
 368 void
 369 lp_setup_set_fs_functions( struct setup_context *setup,
 370                            lp_jit_frag_func jit_function0,
 371                            lp_jit_frag_func jit_function1,
 372                            boolean opaque )
 373 {
 374    LP_DBG(DEBUG_SETUP, "%s %p\n", __FUNCTION__, (void *) jit_function0);
 375    /* FIXME: reference count */
 376
 377    setup->fs.current.jit_function[0] = jit_function0;
 378    setup->fs.current.jit_function[1] = jit_function1;
 379    setup->fs.current.opaque = opaque;
 380    setup->dirty |= LP_SETUP_NEW_FS;
 381 }
 382
 383 void
 384 lp_setup_set_fs_constants(struct setup_context *setup,
 385                           struct pipe_buffer *buffer)
 386 {
 387    LP_DBG(DEBUG_SETUP, "%s %p\n", __FUNCTION__, (void *) buffer);
 388
 389    pipe_buffer_reference(&setup->constants.current, buffer);
 390
 391    setup->dirty |= LP_SETUP_NEW_CONSTANTS;
 392 }
 393
 394
 395 void
 396 lp_setup_set_alpha_ref_value( struct setup_context *setup,
 397                               float alpha_ref_value )
 398 {
 399    LP_DBG(DEBUG_SETUP, "%s %f\n", __FUNCTION__, alpha_ref_value);
 400
 401    if(setup->fs.current.jit_context.alpha_ref_value != alpha_ref_value) {
 402       setup->fs.current.jit_context.alpha_ref_value = alpha_ref_value;
 403       setup->dirty |= LP_SETUP_NEW_FS;
 404    }
 405 }
 406
 407 void
 408 lp_setup_set_blend_color( struct setup_context *setup,
 409                           const struct pipe_blend_color *blend_color )
 410 {
 411    LP_DBG(DEBUG_SETUP, "%s\n", __FUNCTION__);
 412
 413    assert(blend_color);
 414
 415    if(memcmp(&setup->blend_color.current, blend_color, sizeof *blend_color) != 0) {
 416       memcpy(&setup->blend_color.current, blend_color, sizeof *blend_color);
 417       setup->dirty |= LP_SETUP_NEW_BLEND_COLOR;
 418    }
 419 }
 420
 421
 422 void
 423 lp_setup_set_scissor( struct setup_context *setup,
 424                       const struct pipe_scissor_state *scissor )
 425 {
 426    LP_DBG(DEBUG_SETUP, "%s\n", __FUNCTION__);
 427
 428    assert(scissor);
 429
 430    if (memcmp(&setup->scissor.current, scissor, sizeof(*scissor)) != 0) {
 431       setup->scissor.current = *scissor; /* struct copy */
 432       setup->dirty |= LP_SETUP_NEW_SCISSOR;
 433    }
 434 }
 435
 436
 437 void
 438 lp_setup_set_flatshade_first( struct setup_context *setup,
 439                               boolean flatshade_first )
 440 {
 441    setup->flatshade_first = flatshade_first;
 442 }
 443
 444
 445 void
 446 lp_setup_set_vertex_info( struct setup_context *setup,
 447                           struct vertex_info *vertex_info )
 448 {
 449    /* XXX: just silently holding onto the pointer:
 450     */
 451    setup->vertex_info = vertex_info;
 452 }
 453
 454
 455 /**
 456  * Called during state validation when LP_NEW_TEXTURE is set.
 457  */
 458 void
 459 lp_setup_set_sampler_textures( struct setup_context *setup,
 460                                unsigned num, struct pipe_texture **texture)
 461 {
 462    unsigned i;
 463
 464    LP_DBG(DEBUG_SETUP, "%s\n", __FUNCTION__);
 465
 466    assert(num <= PIPE_MAX_SAMPLERS);
 467
 468    for (i = 0; i < PIPE_MAX_SAMPLERS; i++) {
 469       struct pipe_texture *tex = i < num ? texture[i] : NULL;
 470
 471       if(tex) {
 472          struct llvmpipe_texture *lp_tex = llvmpipe_texture(tex);
 473          struct lp_jit_texture *jit_tex;
 474          jit_tex = &setup->fs.current.jit_context.textures[i];
 475          jit_tex->width = tex->width0;
 476          jit_tex->height = tex->height0;
 477          jit_tex->stride = lp_tex->stride[0];
 478          if(!lp_tex->dt) {
 479             jit_tex->data = lp_tex->data;
 480          }
 481          else {
 482             /*
 483              * XXX: Where should this be unmapped?
 484              */
 485
 486             struct llvmpipe_screen *screen = llvmpipe_screen(tex->screen);
 487             struct llvmpipe_winsys *winsys = screen->winsys;
 488             jit_tex->data = winsys->displaytarget_map(winsys, lp_tex->dt,
 489                                                       PIPE_BUFFER_USAGE_CPU_READ);
 490             assert(jit_tex->data);
 491          }
 492
 493          /* the scene references this texture */
 494          {
 495             struct lp_scene *scene = lp_setup_get_current_scene(setup);
 496             lp_scene_texture_reference(scene, tex);
 497          }
 498       }
 499    }
 500
 501    setup->dirty |= LP_SETUP_NEW_FS;
 502 }
 503
 504
 505 /**
 506  * Is the given texture referenced by any scene?
 507  * Note: we have to check all scenes including any scenes currently
 508  * being rendered and the current scene being built.
 509  */
 510 unsigned
 511 lp_setup_is_texture_referenced( const struct setup_context *setup,
 512                                 const struct pipe_texture *texture )
 513 {
 514    unsigned i;
 515
 516    /* check the render targets */
 517    for (i = 0; i < setup->fb.nr_cbufs; i++) {
 518       if (setup->fb.cbufs[i]->texture == texture)
 519          return PIPE_REFERENCED_FOR_READ | PIPE_REFERENCED_FOR_WRITE;
 520    }
 521    if (setup->fb.zsbuf && setup->fb.zsbuf->texture == texture) {
 522       return PIPE_REFERENCED_FOR_READ | PIPE_REFERENCED_FOR_WRITE;
 523    }
 524
 525    /* check textures referenced by the scene */
 526    for (i = 0; i < Elements(setup->scenes); i++) {
 527       if (lp_scene_is_texture_referenced(setup->scenes[i], texture)) {
 528          return PIPE_REFERENCED_FOR_READ;
 529       }
 530    }
 531
 532    return PIPE_UNREFERENCED;
 533 }
 534
 535
 536 /**
 537  * Called by vbuf code when we're about to draw something.
 538  */
 539 void
 540 lp_setup_update_state( struct setup_context *setup )
 541 {
 542    struct lp_scene *scene = lp_setup_get_current_scene(setup);
 543
 544    LP_DBG(DEBUG_SETUP, "%s\n", __FUNCTION__);
 545
 546    assert(setup->fs.current.jit_function);
 547
 548    if(setup->dirty & LP_SETUP_NEW_BLEND_COLOR) {
 549       uint8_t *stored;
 550       unsigned i, j;
 551
 552       stored = lp_scene_alloc_aligned(scene, 4 * 16, 16);
 553
 554       /* smear each blend color component across 16 ubyte elements */
 555       for (i = 0; i < 4; ++i) {
 556          uint8_t c = float_to_ubyte(setup->blend_color.current.color[i]);
 557          for (j = 0; j < 16; ++j)
 558             stored[i*16 + j] = c;
 559       }
 560
 561       setup->blend_color.stored = stored;
 562
 563       setup->fs.current.jit_context.blend_color = setup->blend_color.stored;
 564       setup->dirty |= LP_SETUP_NEW_FS;
 565    }
 566
 567    if (setup->dirty & LP_SETUP_NEW_SCISSOR) {
 568       float *stored;
 569
 570       stored = lp_scene_alloc_aligned(scene, 4 * sizeof(int32_t), 16);
 571
 572       stored[0] = (float) setup->scissor.current.minx;
 573       stored[1] = (float) setup->scissor.current.miny;
 574       stored[2] = (float) setup->scissor.current.maxx;
 575       stored[3] = (float) setup->scissor.current.maxy;
 576
 577       setup->scissor.stored = stored;
 578
 579       setup->fs.current.jit_context.scissor_xmin = stored[0];
 580       setup->fs.current.jit_context.scissor_ymin = stored[1];
 581       setup->fs.current.jit_context.scissor_xmax = stored[2];
 582       setup->fs.current.jit_context.scissor_ymax = stored[3];
 583
 584       setup->dirty |= LP_SETUP_NEW_FS;
 585    }
 586
 587    if(setup->dirty & LP_SETUP_NEW_CONSTANTS) {
 588       struct pipe_buffer *buffer = setup->constants.current;
 589
 590       if(buffer) {
 591          unsigned current_size = buffer->size;
 592          const void *current_data = llvmpipe_buffer(buffer)->data;
 593
 594          /* TODO: copy only the actually used constants? */
 595
 596          if(setup->constants.stored_size != current_size ||
 597             !setup->constants.stored_data ||
 598             memcmp(setup->constants.stored_data,
 599                    current_data,
 600                    current_size) != 0) {
 601             void *stored;
 602
 603             stored = lp_scene_alloc(scene, current_size);
 604             if(stored) {
 605                memcpy(stored,
 606                       current_data,
 607                       current_size);
 608                setup->constants.stored_size = current_size;
 609                setup->constants.stored_data = stored;
 610             }
 611          }
 612       }
 613       else {
 614          setup->constants.stored_size = 0;
 615          setup->constants.stored_data = NULL;
 616       }
 617
 618       setup->fs.current.jit_context.constants = setup->constants.stored_data;
 619       setup->dirty |= LP_SETUP_NEW_FS;
 620    }
 621
 622
 623    if(setup->dirty & LP_SETUP_NEW_FS) {
 624       if(!setup->fs.stored ||
 625          memcmp(setup->fs.stored,
 626                 &setup->fs.current,
 627                 sizeof setup->fs.current) != 0) {
 628          /* The fs state that's been stored in the scene is different from
 629           * the new, current state.  So allocate a new lp_rast_state object
 630           * and append it to the bin's setup data buffer.
 631           */
 632          struct lp_rast_state *stored =
 633             (struct lp_rast_state *) lp_scene_alloc(scene, sizeof *stored);
 634          if(stored) {
 635             memcpy(stored,
 636                    &setup->fs.current,
 637                    sizeof setup->fs.current);
 638             setup->fs.stored = stored;
 639
 640             /* put the state-set command into all bins */
 641             lp_scene_bin_state_command( scene,
 642                                         lp_rast_set_state,
 643                                         lp_rast_arg_state(setup->fs.stored) );
 644          }
 645       }
 646    }
 647
 648    setup->dirty = 0;
 649
 650    assert(setup->fs.stored);
 651 }
 652
 653
 654
 655 /* Only caller is lp_setup_vbuf_destroy()
 656  */
 657 void
 658 lp_setup_destroy( struct setup_context *setup )
 659 {
 660    reset_context( setup );
 661
 662    pipe_buffer_reference(&setup->constants.current, NULL);
 663
 664    /* free the scenes in the 'empty' queue */
 665    while (1) {
 666       struct lp_scene *scene = lp_scene_dequeue(setup->empty_scenes, FALSE);
 667       if (!scene)
 668          break;
 669       lp_scene_destroy(scene);
 670    }
 671
 672    lp_rast_destroy( setup->rast );
 673
 674    FREE( setup );
 675 }
 676
 677
 678 /**
 679  * Create a new primitive tiling engine.  Plug it into the backend of
 680  * the draw module.  Currently also creates a rasterizer to use with
 681  * it.
 682  */
 683 struct setup_context *
 684 lp_setup_create( struct pipe_screen *screen,
 685                  struct draw_context *draw )
 686 {
 687    unsigned i;
 688    struct setup_context *setup = CALLOC_STRUCT(setup_context);
 689
 690    if (!setup)
 691       return NULL;
 692
 693    lp_setup_init_vbuf(setup);
 694
 695    setup->empty_scenes = lp_scene_queue_create();
 696    if (!setup->empty_scenes)
 697       goto fail;
 698
 699    setup->rast = lp_rast_create( screen, setup->empty_scenes );
 700    if (!setup->rast)
 701       goto fail;
 702
 703    setup->vbuf = draw_vbuf_stage(draw, &setup->base);
 704    if (!setup->vbuf)
 705       goto fail;
 706
 707    draw_set_rasterize_stage(draw, setup->vbuf);
 708    draw_set_render(draw, &setup->base);
 709
 710    /* create some empty scenes */
 711    for (i = 0; i < MAX_SCENES; i++) {
 712       setup->scenes[i] = lp_scene_create();
 713       lp_scene_enqueue(setup->empty_scenes, setup->scenes[i]);
 714    }
 715
 716    setup->triangle = first_triangle;
 717    setup->line     = first_line;
 718    setup->point    = first_point;
 719
 720    setup->dirty = ~0;
 721
 722    return setup;
 723
 724 fail:
 725    if (setup->rast)
 726       lp_rast_destroy( setup->rast );
 727
 728    if (setup->vbuf)
 729       ;
 730
 731    if (setup->empty_scenes)
 732       lp_scene_queue_destroy(setup->empty_scenes);
 733
 734    FREE(setup);
 735    return NULL;
 736 }
 737