src/gallium/auxiliary/draw/draw_pipe_pstipple.c

   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  * Polygon stipple stage:  implement polygon stipple with texture map and
  30  * fragment program.  The fragment program samples the texture and does
  31  * a fragment kill for the stipple-failing fragments.
  32  *
  33  * Authors:  Brian Paul
  34  */
  35
  36
  37 #include "pipe/p_util.h"
  38 #include "pipe/p_inlines.h"
  39 #include "pipe/p_context.h"
  40 #include "pipe/p_defines.h"
  41 #include "pipe/p_shader_tokens.h"
  42
  43 #include "tgsi/util/tgsi_transform.h"
  44 #include "tgsi/util/tgsi_dump.h"
  45
  46 #include "draw_context.h"
  47 #include "draw_pipe.h"
  48
  49
  50
  51 /**
  52  * Subclass of pipe_shader_state to carry extra fragment shader info.
  53  */
  54 struct pstip_fragment_shader
  55 {
  56    struct pipe_shader_state state;
  57    void *driver_fs;
  58    void *pstip_fs;
  59    uint sampler_unit;
  60 };
  61
  62
  63 /**
  64  * Subclass of draw_stage
  65  */
  66 struct pstip_stage
  67 {
  68    struct draw_stage stage;
  69
  70    void *sampler_cso;
  71    struct pipe_texture *texture;
  72    uint num_samplers;
  73    uint num_textures;
  74
  75    /*
  76     * Currently bound state
  77     */
  78    struct pstip_fragment_shader *fs;
  79    struct {
  80       void *samplers[PIPE_MAX_SAMPLERS];
  81       struct pipe_texture *textures[PIPE_MAX_SAMPLERS];
  82       const struct pipe_poly_stipple *stipple;
  83    } state;
  84
  85    /*
  86     * Driver interface/override functions
  87     */
  88    void * (*driver_create_fs_state)(struct pipe_context *,
  89                                     const struct pipe_shader_state *);
  90    void (*driver_bind_fs_state)(struct pipe_context *, void *);
  91    void (*driver_delete_fs_state)(struct pipe_context *, void *);
  92
  93    void (*driver_bind_sampler_states)(struct pipe_context *, unsigned, void **);
  94
  95    void (*driver_set_sampler_textures)(struct pipe_context *, unsigned,
  96                                        struct pipe_texture **);
  97
  98    void (*driver_set_polygon_stipple)(struct pipe_context *,
  99                                       const struct pipe_poly_stipple *);
 100
 101    struct pipe_context *pipe;
 102 };
 103
 104
 105
 106 /**
 107  * Subclass of tgsi_transform_context, used for transforming the
 108  * user's fragment shader to add the special AA instructions.
 109  */
 110 struct pstip_transform_context {
 111    struct tgsi_transform_context base;
 112    uint tempsUsed;  /**< bitmask */
 113    int wincoordInput;
 114    int maxInput;
 115    uint samplersUsed;  /**< bitfield of samplers used */
 116    int freeSampler;  /** an available sampler for the pstipple */
 117    int texTemp;  /**< temp registers */
 118    int numImmed;
 119    boolean firstInstruction;
 120 };
 121
 122
 123 /**
 124  * TGSI declaration transform callback.
 125  * Look for a free sampler, a free input attrib, and two free temp regs.
 126  */
 127 static void
 128 pstip_transform_decl(struct tgsi_transform_context *ctx,
 129                      struct tgsi_full_declaration *decl)
 130 {
 131    struct pstip_transform_context *pctx = (struct pstip_transform_context *) ctx;
 132
 133    if (decl->Declaration.File == TGSI_FILE_SAMPLER) {
 134       uint i;
 135       for (i = decl->u.DeclarationRange.First;
 136            i <= decl->u.DeclarationRange.Last; i++) {
 137          pctx->samplersUsed |= 1 << i;
 138       }
 139    }
 140    else if (decl->Declaration.File == TGSI_FILE_INPUT) {
 141       pctx->maxInput = MAX2(pctx->maxInput, (int) decl->u.DeclarationRange.Last);
 142       if (decl->Semantic.SemanticName == TGSI_SEMANTIC_POSITION)
 143          pctx->wincoordInput = (int) decl->u.DeclarationRange.First;
 144    }
 145    else if (decl->Declaration.File == TGSI_FILE_TEMPORARY) {
 146       uint i;
 147       for (i = decl->u.DeclarationRange.First;
 148            i <= decl->u.DeclarationRange.Last; i++) {
 149          pctx->tempsUsed |= (1 << i);
 150       }
 151    }
 152
 153    ctx->emit_declaration(ctx, decl);
 154 }
 155
 156
 157 static void
 158 pstip_transform_immed(struct tgsi_transform_context *ctx,
 159                       struct tgsi_full_immediate *immed)
 160 {
 161    struct pstip_transform_context *pctx = (struct pstip_transform_context *) ctx;
 162    pctx->numImmed++;
 163 }
 164
 165
 166 /**
 167  * Find the lowest zero bit in the given word, or -1 if bitfield is all ones.
 168  */
 169 static int
 170 free_bit(uint bitfield)
 171 {
 172    int i;
 173    for (i = 0; i < 32; i++) {
 174       if ((bitfield & (1 << i)) == 0)
 175          return i;
 176    }
 177    return -1;
 178 }
 179
 180
 181 /**
 182  * TGSI instruction transform callback.
 183  * Replace writes to result.color w/ a temp reg.
 184  * Upon END instruction, insert texture sampling code for antialiasing.
 185  */
 186 static void
 187 pstip_transform_inst(struct tgsi_transform_context *ctx,
 188                      struct tgsi_full_instruction *inst)
 189 {
 190    struct pstip_transform_context *pctx = (struct pstip_transform_context *) ctx;
 191
 192    if (pctx->firstInstruction) {
 193       /* emit our new declarations before the first instruction */
 194
 195       struct tgsi_full_declaration decl;
 196       struct tgsi_full_instruction newInst;
 197       uint i;
 198       int wincoordInput;
 199
 200       /* find free sampler */
 201       pctx->freeSampler = free_bit(pctx->samplersUsed);
 202       if (pctx->freeSampler >= PIPE_MAX_SAMPLERS)
 203          pctx->freeSampler = PIPE_MAX_SAMPLERS - 1;
 204
 205       if (pctx->wincoordInput < 0)
 206          wincoordInput = pctx->maxInput + 1;
 207       else
 208          wincoordInput = pctx->wincoordInput;
 209
 210       /* find one free temp reg */
 211       for (i = 0; i < 32; i++) {
 212          if ((pctx->tempsUsed & (1 << i)) == 0) {
 213             /* found a free temp */
 214             if (pctx->texTemp < 0)
 215                pctx->texTemp  = i;
 216             else
 217                break;
 218          }
 219       }
 220       assert(pctx->texTemp >= 0);
 221
 222       if (pctx->wincoordInput < 0) {
 223          /* declare new position input reg */
 224          decl = tgsi_default_full_declaration();
 225          decl.Declaration.File = TGSI_FILE_INPUT;
 226          decl.Declaration.Semantic = 1;
 227          decl.Semantic.SemanticName = TGSI_SEMANTIC_POSITION;
 228          decl.Semantic.SemanticIndex = 0;
 229          decl.Declaration.Interpolate = 1;
 230          decl.Interpolation.Interpolate = TGSI_INTERPOLATE_LINEAR; /* XXX? */
 231          decl.u.DeclarationRange.First =
 232             decl.u.DeclarationRange.Last = wincoordInput;
 233          ctx->emit_declaration(ctx, &decl);
 234       }
 235
 236       /* declare new sampler */
 237       decl = tgsi_default_full_declaration();
 238       decl.Declaration.File = TGSI_FILE_SAMPLER;
 239       decl.u.DeclarationRange.First =
 240       decl.u.DeclarationRange.Last = pctx->freeSampler;
 241       ctx->emit_declaration(ctx, &decl);
 242
 243       /* declare new temp regs */
 244       decl = tgsi_default_full_declaration();
 245       decl.Declaration.File = TGSI_FILE_TEMPORARY;
 246       decl.u.DeclarationRange.First =
 247       decl.u.DeclarationRange.Last = pctx->texTemp;
 248       ctx->emit_declaration(ctx, &decl);
 249
 250       /* emit immediate = {1/32, 1/32, 1, 1}
 251        * The index/position of this immediate will be pctx->numImmed
 252        */
 253       {
 254          static const float value[4] = { 1.0/32, 1.0/32, 1.0, 1.0 };
 255          struct tgsi_full_immediate immed;
 256          uint size = 4;
 257          immed = tgsi_default_full_immediate();
 258          immed.Immediate.Size = 1 + size; /* one for the token itself */
 259          immed.u.Pointer = (void *) value;
 260          ctx->emit_immediate(ctx, &immed);
 261       }
 262
 263       pctx->firstInstruction = FALSE;
 264
 265
 266       /*
 267        * Insert new MUL/TEX/KILP instructions at start of program
 268        * Take gl_FragCoord, divide by 32 (stipple size), sample the
 269        * texture and kill fragment if needed.
 270        *
 271        * We'd like to use non-normalized texcoords to index into a RECT
 272        * texture, but we can only use GL_REPEAT wrap mode with normalized
 273        * texcoords.  Darn.
 274        */
 275
 276       /* MUL texTemp, INPUT[wincoord], 1/32; */
 277       newInst = tgsi_default_full_instruction();
 278       newInst.Instruction.Opcode = TGSI_OPCODE_MUL;
 279       newInst.Instruction.NumDstRegs = 1;
 280       newInst.FullDstRegisters[0].DstRegister.File = TGSI_FILE_TEMPORARY;
 281       newInst.FullDstRegisters[0].DstRegister.Index = pctx->texTemp;
 282       newInst.Instruction.NumSrcRegs = 2;
 283       newInst.FullSrcRegisters[0].SrcRegister.File = TGSI_FILE_INPUT;
 284       newInst.FullSrcRegisters[0].SrcRegister.Index = wincoordInput;
 285       newInst.FullSrcRegisters[1].SrcRegister.File = TGSI_FILE_IMMEDIATE;
 286       newInst.FullSrcRegisters[1].SrcRegister.Index = pctx->numImmed;
 287       ctx->emit_instruction(ctx, &newInst);
 288
 289       /* TEX texTemp, texTemp, sampler; */
 290       newInst = tgsi_default_full_instruction();
 291       newInst.Instruction.Opcode = TGSI_OPCODE_TEX;
 292       newInst.Instruction.NumDstRegs = 1;
 293       newInst.FullDstRegisters[0].DstRegister.File = TGSI_FILE_TEMPORARY;
 294       newInst.FullDstRegisters[0].DstRegister.Index = pctx->texTemp;
 295       newInst.Instruction.NumSrcRegs = 2;
 296       newInst.InstructionExtTexture.Texture = TGSI_TEXTURE_2D;
 297       newInst.FullSrcRegisters[0].SrcRegister.File = TGSI_FILE_TEMPORARY;
 298       newInst.FullSrcRegisters[0].SrcRegister.Index = pctx->texTemp;
 299       newInst.FullSrcRegisters[1].SrcRegister.File = TGSI_FILE_SAMPLER;
 300       newInst.FullSrcRegisters[1].SrcRegister.Index = pctx->freeSampler;
 301       ctx->emit_instruction(ctx, &newInst);
 302
 303       /* KILP texTemp;   # if texTemp < 0, KILL fragment */
 304       newInst = tgsi_default_full_instruction();
 305       newInst.Instruction.Opcode = TGSI_OPCODE_KILP;
 306       newInst.Instruction.NumDstRegs = 0;
 307       newInst.Instruction.NumSrcRegs = 1;
 308       newInst.FullSrcRegisters[0].SrcRegister.File = TGSI_FILE_TEMPORARY;
 309       newInst.FullSrcRegisters[0].SrcRegister.Index = pctx->texTemp;
 310       newInst.FullSrcRegisters[0].SrcRegister.Negate = 1;
 311       ctx->emit_instruction(ctx, &newInst);
 312    }
 313
 314    /* emit this instruction */
 315    ctx->emit_instruction(ctx, inst);
 316 }
 317
 318
 319 /**
 320  * Generate the frag shader we'll use for doing polygon stipple.
 321  * This will be the user's shader prefixed with a TEX and KIL instruction.
 322  */
 323 static boolean
 324 generate_pstip_fs(struct pstip_stage *pstip)
 325 {
 326    const struct pipe_shader_state *orig_fs = &pstip->fs->state;
 327    /*struct draw_context *draw = pstip->stage.draw;*/
 328    struct pipe_shader_state pstip_fs;
 329    struct pstip_transform_context transform;
 330
 331 #define MAX 1000
 332
 333    pstip_fs = *orig_fs; /* copy to init */
 334    pstip_fs.tokens = MALLOC(sizeof(struct tgsi_token) * MAX);
 335    if (pstip_fs.tokens == NULL)
 336       return FALSE;
 337
 338    memset(&transform, 0, sizeof(transform));
 339    transform.wincoordInput = -1;
 340    transform.maxInput = -1;
 341    transform.texTemp = -1;
 342    transform.firstInstruction = TRUE;
 343    transform.base.transform_instruction = pstip_transform_inst;
 344    transform.base.transform_declaration = pstip_transform_decl;
 345    transform.base.transform_immediate = pstip_transform_immed;
 346
 347    tgsi_transform_shader(orig_fs->tokens,
 348                          (struct tgsi_token *) pstip_fs.tokens,
 349                          MAX, &transform.base);
 350
 351 #if 0 /* DEBUG */
 352    tgsi_dump(orig_fs->tokens, 0);
 353    tgsi_dump(pstip_fs.tokens, 0);
 354 #endif
 355
 356    pstip->fs->sampler_unit = transform.freeSampler;
 357    assert(pstip->fs->sampler_unit < PIPE_MAX_SAMPLERS);
 358
 359    pstip->fs->pstip_fs = pstip->driver_create_fs_state(pstip->pipe, &pstip_fs);
 360
 361    return TRUE;
 362 }
 363
 364
 365 /**
 366  * Load texture image with current stipple pattern.
 367  */
 368 static void
 369 pstip_update_texture(struct pstip_stage *pstip)
 370 {
 371    static const uint bit31 = 1 << 31;
 372    struct pipe_context *pipe = pstip->pipe;
 373    struct pipe_screen *screen = pipe->screen;
 374    struct pipe_surface *surface;
 375    const uint *stipple = pstip->state.stipple->stipple;
 376    uint i, j;
 377    ubyte *data;
 378
 379    /* XXX: want to avoid flushing just because we use stipple:
 380     */
 381    pipe->flush( pipe, PIPE_FLUSH_TEXTURE_CACHE, NULL );
 382
 383    surface = screen->get_tex_surface(screen, pstip->texture, 0, 0, 0,
 384                                      PIPE_BUFFER_USAGE_CPU_WRITE);
 385    data = screen->surface_map(screen, surface,
 386                               PIPE_BUFFER_USAGE_CPU_WRITE);
 387
 388    /*
 389     * Load alpha texture.
 390     * Note: 0 means keep the fragment, 255 means kill it.
 391     * We'll negate the texel value and use KILP which kills if value
 392     * is negative.
 393     */
 394    for (i = 0; i < 32; i++) {
 395       for (j = 0; j < 32; j++) {
 396          if (stipple[i] & (bit31 >> j)) {
 397             /* fragment "on" */
 398             data[i * surface->pitch + j] = 0;
 399          }
 400          else {
 401             /* fragment "off" */
 402             data[i * surface->pitch + j] = 255;
 403          }
 404       }
 405    }
 406
 407    /* unmap */
 408    screen->surface_unmap(screen, surface);
 409    screen->tex_surface_release(screen, &surface);
 410 }
 411
 412
 413 /**
 414  * Create the texture map we'll use for stippling.
 415  */
 416 static boolean
 417 pstip_create_texture(struct pstip_stage *pstip)
 418 {
 419    struct pipe_context *pipe = pstip->pipe;
 420    struct pipe_screen *screen = pipe->screen;
 421    struct pipe_texture texTemp;
 422
 423    memset(&texTemp, 0, sizeof(texTemp));
 424    texTemp.target = PIPE_TEXTURE_2D;
 425    texTemp.format = PIPE_FORMAT_A8_UNORM; /* XXX verify supported by driver! */
 426    texTemp.last_level = 0;
 427    texTemp.width[0] = 32;
 428    texTemp.height[0] = 32;
 429    texTemp.depth[0] = 1;
 430    texTemp.cpp = 1;
 431
 432    pstip->texture = screen->texture_create(screen, &texTemp);
 433    if (pstip->texture == NULL)
 434       return FALSE;
 435
 436    return TRUE;
 437 }
 438
 439
 440 /**
 441  * Create the sampler CSO that'll be used for stippling.
 442  */
 443 static boolean
 444 pstip_create_sampler(struct pstip_stage *pstip)
 445 {
 446    struct pipe_sampler_state sampler;
 447    struct pipe_context *pipe = pstip->pipe;
 448
 449    memset(&sampler, 0, sizeof(sampler));
 450    sampler.wrap_s = PIPE_TEX_WRAP_REPEAT;
 451    sampler.wrap_t = PIPE_TEX_WRAP_REPEAT;
 452    sampler.wrap_r = PIPE_TEX_WRAP_REPEAT;
 453    sampler.min_mip_filter = PIPE_TEX_MIPFILTER_NONE;
 454    sampler.min_img_filter = PIPE_TEX_FILTER_NEAREST;
 455    sampler.mag_img_filter = PIPE_TEX_FILTER_NEAREST;
 456    sampler.normalized_coords = 1;
 457    sampler.min_lod = 0.0f;
 458    sampler.max_lod = 0.0f;
 459
 460    pstip->sampler_cso = pipe->create_sampler_state(pipe, &sampler);
 461    if (pstip->sampler_cso == NULL)
 462       return FALSE;
 463
 464    return TRUE;
 465 }
 466
 467
 468 /**
 469  * When we're about to draw our first stipple polygon in a batch, this function
 470  * is called to tell the driver to bind our modified fragment shader.
 471  */
 472 static boolean
 473 bind_pstip_fragment_shader(struct pstip_stage *pstip)
 474 {
 475    struct draw_context *draw = pstip->stage.draw;
 476    if (!pstip->fs->pstip_fs &&
 477        !generate_pstip_fs(pstip))
 478       return FALSE;
 479
 480    draw->suspend_flushing = TRUE;
 481    pstip->driver_bind_fs_state(pstip->pipe, pstip->fs->pstip_fs);
 482    draw->suspend_flushing = FALSE;
 483    return TRUE;
 484 }
 485
 486
 487 static INLINE struct pstip_stage *
 488 pstip_stage( struct draw_stage *stage )
 489 {
 490    return (struct pstip_stage *) stage;
 491 }
 492
 493
 494 static void
 495 pstip_first_tri(struct draw_stage *stage, struct prim_header *header)
 496 {
 497    struct pstip_stage *pstip = pstip_stage(stage);
 498    struct pipe_context *pipe = pstip->pipe;
 499    struct draw_context *draw = stage->draw;
 500    uint num_samplers;
 501
 502    assert(stage->draw->rasterizer->poly_stipple_enable);
 503
 504    /* bind our fragprog */
 505    if (!bind_pstip_fragment_shader(pstip)) {
 506       stage->tri = draw_pipe_passthrough_tri;
 507       stage->tri(stage, header);
 508       return;
 509    }
 510
 511
 512    /* how many samplers? */
 513    /* we'll use sampler/texture[pstip->sampler_unit] for the stipple */
 514    num_samplers = MAX2(pstip->num_textures, pstip->num_samplers);
 515    num_samplers = MAX2(num_samplers, pstip->fs->sampler_unit + 1);
 516
 517    /* plug in our sampler, texture */
 518    pstip->state.samplers[pstip->fs->sampler_unit] = pstip->sampler_cso;
 519    pipe_texture_reference(&pstip->state.textures[pstip->fs->sampler_unit],
 520                           pstip->texture);
 521
 522    assert(num_samplers <= PIPE_MAX_SAMPLERS);
 523
 524    draw->suspend_flushing = TRUE;
 525    pstip->driver_bind_sampler_states(pipe, num_samplers, pstip->state.samplers);
 526    pstip->driver_set_sampler_textures(pipe, num_samplers, pstip->state.textures);
 527    draw->suspend_flushing = FALSE;
 528
 529    /* now really draw first triangle */
 530    stage->tri = draw_pipe_passthrough_tri;
 531    stage->tri(stage, header);
 532 }
 533
 534
 535 static void
 536 pstip_flush(struct draw_stage *stage, unsigned flags)
 537 {
 538    struct draw_context *draw = stage->draw;
 539    struct pstip_stage *pstip = pstip_stage(stage);
 540    struct pipe_context *pipe = pstip->pipe;
 541
 542    stage->tri = pstip_first_tri;
 543    stage->next->flush( stage->next, flags );
 544
 545    /* restore original frag shader, texture, sampler state */
 546    draw->suspend_flushing = TRUE;
 547    pstip->driver_bind_fs_state(pipe, pstip->fs->driver_fs);
 548    pstip->driver_bind_sampler_states(pipe, pstip->num_samplers,
 549                                      pstip->state.samplers);
 550    pstip->driver_set_sampler_textures(pipe, pstip->num_textures,
 551                                       pstip->state.textures);
 552    draw->suspend_flushing = FALSE;
 553 }
 554
 555
 556 static void
 557 pstip_reset_stipple_counter(struct draw_stage *stage)
 558 {
 559    stage->next->reset_stipple_counter( stage->next );
 560 }
 561
 562
 563 static void
 564 pstip_destroy(struct draw_stage *stage)
 565 {
 566    struct pstip_stage *pstip = pstip_stage(stage);
 567    uint i;
 568
 569    for (i = 0; i < PIPE_MAX_SAMPLERS; i++) {
 570       pipe_texture_reference(&pstip->state.textures[i], NULL);
 571    }
 572
 573    pstip->pipe->delete_sampler_state(pstip->pipe, pstip->sampler_cso);
 574
 575    pipe_texture_release(&pstip->texture);
 576
 577    draw_free_temp_verts( stage );
 578    FREE( stage );
 579 }
 580
 581
 582 static struct pstip_stage *
 583 draw_pstip_stage(struct draw_context *draw)
 584 {
 585    struct pstip_stage *pstip = CALLOC_STRUCT(pstip_stage);
 586
 587    draw_alloc_temp_verts( &pstip->stage, 8 );
 588
 589    pstip->stage.draw = draw;
 590    pstip->stage.next = NULL;
 591    pstip->stage.point = draw_pipe_passthrough_point;
 592    pstip->stage.line = draw_pipe_passthrough_line;
 593    pstip->stage.tri = pstip_first_tri;
 594    pstip->stage.flush = pstip_flush;
 595    pstip->stage.reset_stipple_counter = pstip_reset_stipple_counter;
 596    pstip->stage.destroy = pstip_destroy;
 597
 598    return pstip;
 599 }
 600
 601
 602 static struct pstip_stage *
 603 pstip_stage_from_pipe(struct pipe_context *pipe)
 604 {
 605    struct draw_context *draw = (struct draw_context *) pipe->draw;
 606    return pstip_stage(draw->pipeline.pstipple);
 607 }
 608
 609
 610 /**
 611  * This function overrides the driver's create_fs_state() function and
 612  * will typically be called by the state tracker.
 613  */
 614 static void *
 615 pstip_create_fs_state(struct pipe_context *pipe,
 616                        const struct pipe_shader_state *fs)
 617 {
 618    struct pstip_stage *pstip = pstip_stage_from_pipe(pipe);
 619    struct pstip_fragment_shader *aafs = CALLOC_STRUCT(pstip_fragment_shader);
 620
 621    if (aafs) {
 622       aafs->state = *fs;
 623
 624       /* pass-through */
 625       aafs->driver_fs = pstip->driver_create_fs_state(pstip->pipe, fs);
 626    }
 627
 628    return aafs;
 629 }
 630
 631
 632 static void
 633 pstip_bind_fs_state(struct pipe_context *pipe, void *fs)
 634 {
 635    struct pstip_stage *pstip = pstip_stage_from_pipe(pipe);
 636    struct pstip_fragment_shader *aafs = (struct pstip_fragment_shader *) fs;
 637    /* save current */
 638    pstip->fs = aafs;
 639    /* pass-through */
 640    pstip->driver_bind_fs_state(pstip->pipe,
 641                                (aafs ? aafs->driver_fs : NULL));
 642 }
 643
 644
 645 static void
 646 pstip_delete_fs_state(struct pipe_context *pipe, void *fs)
 647 {
 648    struct pstip_stage *pstip = pstip_stage_from_pipe(pipe);
 649    struct pstip_fragment_shader *aafs = (struct pstip_fragment_shader *) fs;
 650    /* pass-through */
 651    pstip->driver_delete_fs_state(pstip->pipe, aafs->driver_fs);
 652    FREE(aafs);
 653 }
 654
 655
 656 static void
 657 pstip_bind_sampler_states(struct pipe_context *pipe,
 658                           unsigned num, void **sampler)
 659 {
 660    struct pstip_stage *pstip = pstip_stage_from_pipe(pipe);
 661    uint i;
 662
 663    /* save current */
 664    memcpy(pstip->state.samplers, sampler, num * sizeof(void *));
 665    for (i = num; i < PIPE_MAX_SAMPLERS; i++) {
 666       pstip->state.samplers[i] = NULL;
 667    }
 668
 669    pstip->num_samplers = num;
 670    /* pass-through */
 671    pstip->driver_bind_sampler_states(pstip->pipe, num, sampler);
 672 }
 673
 674
 675 static void
 676 pstip_set_sampler_textures(struct pipe_context *pipe,
 677                            unsigned num, struct pipe_texture **texture)
 678 {
 679    struct pstip_stage *pstip = pstip_stage_from_pipe(pipe);
 680    uint i;
 681
 682    /* save current */
 683    for (i = 0; i < num; i++) {
 684       pipe_texture_reference(&pstip->state.textures[i], texture[i]);
 685    }
 686    for (; i < PIPE_MAX_SAMPLERS; i++) {
 687       pipe_texture_reference(&pstip->state.textures[i], NULL);
 688    }
 689
 690    pstip->num_textures = num;
 691
 692    /* pass-through */
 693    pstip->driver_set_sampler_textures(pstip->pipe, num, texture);
 694 }
 695
 696
 697 static void
 698 pstip_set_polygon_stipple(struct pipe_context *pipe,
 699                           const struct pipe_poly_stipple *stipple)
 700 {
 701    struct pstip_stage *pstip = pstip_stage_from_pipe(pipe);
 702
 703    /* save current */
 704    pstip->state.stipple = stipple;
 705
 706    /* pass-through */
 707    pstip->driver_set_polygon_stipple(pstip->pipe, stipple);
 708
 709    pstip_update_texture(pstip);
 710 }
 711
 712
 713 /**
 714  * Called by drivers that want to install this polygon stipple stage
 715  * into the draw module's pipeline.  This will not be used if the
 716  * hardware has native support for polygon stipple.
 717  */
 718 boolean
 719 draw_install_pstipple_stage(struct draw_context *draw,
 720                             struct pipe_context *pipe)
 721 {
 722    struct pstip_stage *pstip;
 723
 724    pipe->draw = (void *) draw;
 725
 726    /*
 727     * Create / install pgon stipple drawing / prim stage
 728     */
 729    pstip = draw_pstip_stage( draw );
 730    if (pstip == NULL)
 731       goto fail;
 732
 733    draw->pipeline.pstipple = &pstip->stage;
 734
 735    pstip->pipe = pipe;
 736
 737    /* create special texture, sampler state */
 738    if (!pstip_create_texture(pstip))
 739       goto fail;
 740
 741    if (!pstip_create_sampler(pstip))
 742       goto fail;
 743
 744    /* save original driver functions */
 745    pstip->driver_create_fs_state = pipe->create_fs_state;
 746    pstip->driver_bind_fs_state = pipe->bind_fs_state;
 747    pstip->driver_delete_fs_state = pipe->delete_fs_state;
 748
 749    pstip->driver_bind_sampler_states = pipe->bind_sampler_states;
 750    pstip->driver_set_sampler_textures = pipe->set_sampler_textures;
 751    pstip->driver_set_polygon_stipple = pipe->set_polygon_stipple;
 752
 753    /* override the driver's functions */
 754    pipe->create_fs_state = pstip_create_fs_state;
 755    pipe->bind_fs_state = pstip_bind_fs_state;
 756    pipe->delete_fs_state = pstip_delete_fs_state;
 757
 758    pipe->bind_sampler_states = pstip_bind_sampler_states;
 759    pipe->set_sampler_textures = pstip_set_sampler_textures;
 760    pipe->set_polygon_stipple = pstip_set_polygon_stipple;
 761
 762    return TRUE;
 763
 764  fail:
 765    if (pstip)
 766       pstip->stage.destroy( &pstip->stage );
 767
 768    return FALSE;
 769 }