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_context.h"
  38 #include "pipe/p_defines.h"
  39 #include "pipe/p_shader_tokens.h"
  40 #include "util/u_inlines.h"
  41
  42 #include "util/u_format.h"
  43 #include "util/u_math.h"
  44 #include "util/u_memory.h"
  45
  46 #include "tgsi/tgsi_transform.h"
  47 #include "tgsi/tgsi_dump.h"
  48
  49 #include "draw_context.h"
  50 #include "draw_pipe.h"
  51
  52
  53 /** Approx number of new tokens for instructions in pstip_transform_inst() */
  54 #define NUM_NEW_TOKENS 50
  55
  56
  57 /**
  58  * Subclass of pipe_shader_state to carry extra fragment shader info.
  59  */
  60 struct pstip_fragment_shader
  61 {
  62    struct pipe_shader_state state;
  63    void *driver_fs;
  64    void *pstip_fs;
  65    uint sampler_unit;
  66 };
  67
  68
  69 /**
  70  * Subclass of draw_stage
  71  */
  72 struct pstip_stage
  73 {
  74    struct draw_stage stage;
  75
  76    void *sampler_cso;
  77    struct pipe_texture *texture;
  78    uint num_samplers;
  79    uint num_textures;
  80
  81    /*
  82     * Currently bound state
  83     */
  84    struct pstip_fragment_shader *fs;
  85    struct {
  86       void *samplers[PIPE_MAX_SAMPLERS];
  87       struct pipe_texture *textures[PIPE_MAX_SAMPLERS];
  88       const struct pipe_poly_stipple *stipple;
  89    } state;
  90
  91    /*
  92     * Driver interface/override functions
  93     */
  94    void * (*driver_create_fs_state)(struct pipe_context *,
  95                                     const struct pipe_shader_state *);
  96    void (*driver_bind_fs_state)(struct pipe_context *, void *);
  97    void (*driver_delete_fs_state)(struct pipe_context *, void *);
  98
  99    void (*driver_bind_sampler_states)(struct pipe_context *, unsigned, void **);
 100
 101    void (*driver_set_sampler_textures)(struct pipe_context *, unsigned,
 102                                        struct pipe_texture **);
 103
 104    void (*driver_set_polygon_stipple)(struct pipe_context *,
 105                                       const struct pipe_poly_stipple *);
 106
 107    struct pipe_context *pipe;
 108 };
 109
 110
 111
 112 /**
 113  * Subclass of tgsi_transform_context, used for transforming the
 114  * user's fragment shader to add the special AA instructions.
 115  */
 116 struct pstip_transform_context {
 117    struct tgsi_transform_context base;
 118    uint tempsUsed;  /**< bitmask */
 119    int wincoordInput;
 120    int maxInput;
 121    uint samplersUsed;  /**< bitfield of samplers used */
 122    int freeSampler;  /** an available sampler for the pstipple */
 123    int texTemp;  /**< temp registers */
 124    int numImmed;
 125    boolean firstInstruction;
 126 };
 127
 128
 129 /**
 130  * TGSI declaration transform callback.
 131  * Look for a free sampler, a free input attrib, and two free temp regs.
 132  */
 133 static void
 134 pstip_transform_decl(struct tgsi_transform_context *ctx,
 135                      struct tgsi_full_declaration *decl)
 136 {
 137    struct pstip_transform_context *pctx = (struct pstip_transform_context *) ctx;
 138
 139    if (decl->Declaration.File == TGSI_FILE_SAMPLER) {
 140       uint i;
 141       for (i = decl->Range.First;
 142            i <= decl->Range.Last; i++) {
 143          pctx->samplersUsed |= 1 << i;
 144       }
 145    }
 146    else if (decl->Declaration.File == TGSI_FILE_INPUT) {
 147       pctx->maxInput = MAX2(pctx->maxInput, (int) decl->Range.Last);
 148       if (decl->Semantic.Name == TGSI_SEMANTIC_POSITION)
 149          pctx->wincoordInput = (int) decl->Range.First;
 150    }
 151    else if (decl->Declaration.File == TGSI_FILE_TEMPORARY) {
 152       uint i;
 153       for (i = decl->Range.First;
 154            i <= decl->Range.Last; i++) {
 155          pctx->tempsUsed |= (1 << i);
 156       }
 157    }
 158
 159    ctx->emit_declaration(ctx, decl);
 160 }
 161
 162
 163 static void
 164 pstip_transform_immed(struct tgsi_transform_context *ctx,
 165                       struct tgsi_full_immediate *immed)
 166 {
 167    struct pstip_transform_context *pctx = (struct pstip_transform_context *) ctx;
 168    pctx->numImmed++;
 169 }
 170
 171
 172 /**
 173  * Find the lowest zero bit in the given word, or -1 if bitfield is all ones.
 174  */
 175 static int
 176 free_bit(uint bitfield)
 177 {
 178    return ffs(~bitfield) - 1;
 179 }
 180
 181
 182 /**
 183  * TGSI instruction transform callback.
 184  * Replace writes to result.color w/ a temp reg.
 185  * Upon END instruction, insert texture sampling code for antialiasing.
 186  */
 187 static void
 188 pstip_transform_inst(struct tgsi_transform_context *ctx,
 189                      struct tgsi_full_instruction *inst)
 190 {
 191    struct pstip_transform_context *pctx = (struct pstip_transform_context *) ctx;
 192
 193    if (pctx->firstInstruction) {
 194       /* emit our new declarations before the first instruction */
 195
 196       struct tgsi_full_declaration decl;
 197       struct tgsi_full_instruction newInst;
 198       uint i;
 199       int wincoordInput;
 200
 201       /* find free sampler */
 202       pctx->freeSampler = free_bit(pctx->samplersUsed);
 203       if (pctx->freeSampler >= PIPE_MAX_SAMPLERS)
 204          pctx->freeSampler = PIPE_MAX_SAMPLERS - 1;
 205
 206       if (pctx->wincoordInput < 0)
 207          wincoordInput = pctx->maxInput + 1;
 208       else
 209          wincoordInput = pctx->wincoordInput;
 210
 211       /* find one free temp reg */
 212       for (i = 0; i < 32; i++) {
 213          if ((pctx->tempsUsed & (1 << i)) == 0) {
 214             /* found a free temp */
 215             if (pctx->texTemp < 0)
 216                pctx->texTemp  = i;
 217             else
 218                break;
 219          }
 220       }
 221       assert(pctx->texTemp >= 0);
 222
 223       if (pctx->wincoordInput < 0) {
 224          /* declare new position input reg */
 225          decl = tgsi_default_full_declaration();
 226          decl.Declaration.File = TGSI_FILE_INPUT;
 227          decl.Declaration.Interpolate = TGSI_INTERPOLATE_LINEAR; /* XXX? */
 228          decl.Declaration.Semantic = 1;
 229          decl.Semantic.Name = TGSI_SEMANTIC_POSITION;
 230          decl.Semantic.Index = 0;
 231          decl.Range.First =
 232             decl.Range.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.Range.First =
 240       decl.Range.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.Range.First =
 247       decl.Range.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.NrTokens = 1 + size; /* one for the token itself */
 259          immed.u[0].Float = value[0];
 260          immed.u[1].Float = value[1];
 261          immed.u[2].Float = value[2];
 262          immed.u[3].Float = value[3];
 263          ctx->emit_immediate(ctx, &immed);
 264       }
 265
 266       pctx->firstInstruction = FALSE;
 267
 268
 269       /*
 270        * Insert new MUL/TEX/KILP instructions at start of program
 271        * Take gl_FragCoord, divide by 32 (stipple size), sample the
 272        * texture and kill fragment if needed.
 273        *
 274        * We'd like to use non-normalized texcoords to index into a RECT
 275        * texture, but we can only use GL_REPEAT wrap mode with normalized
 276        * texcoords.  Darn.
 277        */
 278
 279       /* MUL texTemp, INPUT[wincoord], 1/32; */
 280       newInst = tgsi_default_full_instruction();
 281       newInst.Instruction.Opcode = TGSI_OPCODE_MUL;
 282       newInst.Instruction.NumDstRegs = 1;
 283       newInst.Dst[0].Register.File = TGSI_FILE_TEMPORARY;
 284       newInst.Dst[0].Register.Index = pctx->texTemp;
 285       newInst.Instruction.NumSrcRegs = 2;
 286       newInst.Src[0].Register.File = TGSI_FILE_INPUT;
 287       newInst.Src[0].Register.Index = wincoordInput;
 288       newInst.Src[1].Register.File = TGSI_FILE_IMMEDIATE;
 289       newInst.Src[1].Register.Index = pctx->numImmed;
 290       ctx->emit_instruction(ctx, &newInst);
 291
 292       /* TEX texTemp, texTemp, sampler; */
 293       newInst = tgsi_default_full_instruction();
 294       newInst.Instruction.Opcode = TGSI_OPCODE_TEX;
 295       newInst.Instruction.NumDstRegs = 1;
 296       newInst.Dst[0].Register.File = TGSI_FILE_TEMPORARY;
 297       newInst.Dst[0].Register.Index = pctx->texTemp;
 298       newInst.Instruction.NumSrcRegs = 2;
 299       newInst.Instruction.Texture = TRUE;
 300       newInst.Texture.Texture = TGSI_TEXTURE_2D;
 301       newInst.Src[0].Register.File = TGSI_FILE_TEMPORARY;
 302       newInst.Src[0].Register.Index = pctx->texTemp;
 303       newInst.Src[1].Register.File = TGSI_FILE_SAMPLER;
 304       newInst.Src[1].Register.Index = pctx->freeSampler;
 305       ctx->emit_instruction(ctx, &newInst);
 306
 307       /* KIL -texTemp;   # if -texTemp < 0, KILL fragment */
 308       newInst = tgsi_default_full_instruction();
 309       newInst.Instruction.Opcode = TGSI_OPCODE_KIL;
 310       newInst.Instruction.NumDstRegs = 0;
 311       newInst.Instruction.NumSrcRegs = 1;
 312       newInst.Src[0].Register.File = TGSI_FILE_TEMPORARY;
 313       newInst.Src[0].Register.Index = pctx->texTemp;
 314       newInst.Src[0].Register.Negate = 1;
 315       ctx->emit_instruction(ctx, &newInst);
 316    }
 317
 318    /* emit this instruction */
 319    ctx->emit_instruction(ctx, inst);
 320 }
 321
 322
 323 /**
 324  * Generate the frag shader we'll use for doing polygon stipple.
 325  * This will be the user's shader prefixed with a TEX and KIL instruction.
 326  */
 327 static boolean
 328 generate_pstip_fs(struct pstip_stage *pstip)
 329 {
 330    const struct pipe_shader_state *orig_fs = &pstip->fs->state;
 331    /*struct draw_context *draw = pstip->stage.draw;*/
 332    struct pipe_shader_state pstip_fs;
 333    struct pstip_transform_context transform;
 334    const uint newLen = tgsi_num_tokens(orig_fs->tokens) + NUM_NEW_TOKENS;
 335
 336    pstip_fs = *orig_fs; /* copy to init */
 337    pstip_fs.tokens = tgsi_alloc_tokens(newLen);
 338    if (pstip_fs.tokens == NULL)
 339       return FALSE;
 340
 341    memset(&transform, 0, sizeof(transform));
 342    transform.wincoordInput = -1;
 343    transform.maxInput = -1;
 344    transform.texTemp = -1;
 345    transform.firstInstruction = TRUE;
 346    transform.base.transform_instruction = pstip_transform_inst;
 347    transform.base.transform_declaration = pstip_transform_decl;
 348    transform.base.transform_immediate = pstip_transform_immed;
 349
 350    tgsi_transform_shader(orig_fs->tokens,
 351                          (struct tgsi_token *) pstip_fs.tokens,
 352                          newLen, &transform.base);
 353
 354 #if 0 /* DEBUG */
 355    tgsi_dump(orig_fs->tokens, 0);
 356    tgsi_dump(pstip_fs.tokens, 0);
 357 #endif
 358
 359    pstip->fs->sampler_unit = transform.freeSampler;
 360    assert(pstip->fs->sampler_unit < PIPE_MAX_SAMPLERS);
 361
 362    pstip->fs->pstip_fs = pstip->driver_create_fs_state(pstip->pipe, &pstip_fs);
 363
 364    FREE((void *)pstip_fs.tokens);
 365    return TRUE;
 366 }
 367
 368
 369 /**
 370  * Load texture image with current stipple pattern.
 371  */
 372 static void
 373 pstip_update_texture(struct pstip_stage *pstip)
 374 {
 375    static const uint bit31 = 1 << 31;
 376    struct pipe_context *pipe = pstip->pipe;
 377    struct pipe_transfer *transfer;
 378    const uint *stipple = pstip->state.stipple->stipple;
 379    uint i, j;
 380    ubyte *data;
 381
 382    /* XXX: want to avoid flushing just because we use stipple:
 383     *
 384     * Flush should no longer be necessary if driver is properly
 385     * interleaving drawing and transfers on a given context:
 386     */
 387    pipe->flush( pipe, PIPE_FLUSH_TEXTURE_CACHE, NULL );
 388
 389    transfer = pipe->get_tex_transfer(pipe, pstip->texture, 0, 0, 0,
 390                                      PIPE_TRANSFER_WRITE, 0, 0, 32, 32);
 391    data = pipe->transfer_map(pipe, transfer);
 392
 393    /*
 394     * Load alpha texture.
 395     * Note: 0 means keep the fragment, 255 means kill it.
 396     * We'll negate the texel value and use KILP which kills if value
 397     * is negative.
 398     */
 399    for (i = 0; i < 32; i++) {
 400       for (j = 0; j < 32; j++) {
 401          if (stipple[i] & (bit31 >> j)) {
 402             /* fragment "on" */
 403             data[i * transfer->stride + j] = 0;
 404          }
 405          else {
 406             /* fragment "off" */
 407             data[i * transfer->stride + j] = 255;
 408          }
 409       }
 410    }
 411
 412    /* unmap */
 413    pipe->transfer_unmap(pipe, transfer);
 414    pipe->tex_transfer_destroy(transfer);
 415 }
 416
 417
 418 /**
 419  * Create the texture map we'll use for stippling.
 420  */
 421 static boolean
 422 pstip_create_texture(struct pstip_stage *pstip)
 423 {
 424    struct pipe_context *pipe = pstip->pipe;
 425    struct pipe_screen *screen = pipe->screen;
 426    struct pipe_texture texTemp;
 427
 428    memset(&texTemp, 0, sizeof(texTemp));
 429    texTemp.target = PIPE_TEXTURE_2D;
 430    texTemp.format = PIPE_FORMAT_A8_UNORM; /* XXX verify supported by driver! */
 431    texTemp.last_level = 0;
 432    texTemp.width0 = 32;
 433    texTemp.height0 = 32;
 434    texTemp.depth0 = 1;
 435
 436    pstip->texture = screen->texture_create(screen, &texTemp);
 437    if (pstip->texture == NULL)
 438       return FALSE;
 439
 440    return TRUE;
 441 }
 442
 443
 444 /**
 445  * Create the sampler CSO that'll be used for stippling.
 446  */
 447 static boolean
 448 pstip_create_sampler(struct pstip_stage *pstip)
 449 {
 450    struct pipe_sampler_state sampler;
 451    struct pipe_context *pipe = pstip->pipe;
 452
 453    memset(&sampler, 0, sizeof(sampler));
 454    sampler.wrap_s = PIPE_TEX_WRAP_REPEAT;
 455    sampler.wrap_t = PIPE_TEX_WRAP_REPEAT;
 456    sampler.wrap_r = PIPE_TEX_WRAP_REPEAT;
 457    sampler.min_mip_filter = PIPE_TEX_MIPFILTER_NONE;
 458    sampler.min_img_filter = PIPE_TEX_FILTER_NEAREST;
 459    sampler.mag_img_filter = PIPE_TEX_FILTER_NEAREST;
 460    sampler.normalized_coords = 1;
 461    sampler.min_lod = 0.0f;
 462    sampler.max_lod = 0.0f;
 463
 464    pstip->sampler_cso = pipe->create_sampler_state(pipe, &sampler);
 465    if (pstip->sampler_cso == NULL)
 466       return FALSE;
 467
 468    return TRUE;
 469 }
 470
 471
 472 /**
 473  * When we're about to draw our first stipple polygon in a batch, this function
 474  * is called to tell the driver to bind our modified fragment shader.
 475  */
 476 static boolean
 477 bind_pstip_fragment_shader(struct pstip_stage *pstip)
 478 {
 479    struct draw_context *draw = pstip->stage.draw;
 480    if (!pstip->fs->pstip_fs &&
 481        !generate_pstip_fs(pstip))
 482       return FALSE;
 483
 484    draw->suspend_flushing = TRUE;
 485    pstip->driver_bind_fs_state(pstip->pipe, pstip->fs->pstip_fs);
 486    draw->suspend_flushing = FALSE;
 487    return TRUE;
 488 }
 489
 490
 491 static INLINE struct pstip_stage *
 492 pstip_stage( struct draw_stage *stage )
 493 {
 494    return (struct pstip_stage *) stage;
 495 }
 496
 497
 498 static void
 499 pstip_first_tri(struct draw_stage *stage, struct prim_header *header)
 500 {
 501    struct pstip_stage *pstip = pstip_stage(stage);
 502    struct pipe_context *pipe = pstip->pipe;
 503    struct draw_context *draw = stage->draw;
 504    uint num_samplers;
 505
 506    assert(stage->draw->rasterizer->poly_stipple_enable);
 507
 508    /* bind our fragprog */
 509    if (!bind_pstip_fragment_shader(pstip)) {
 510       stage->tri = draw_pipe_passthrough_tri;
 511       stage->tri(stage, header);
 512       return;
 513    }
 514
 515
 516    /* how many samplers? */
 517    /* we'll use sampler/texture[pstip->sampler_unit] for the stipple */
 518    num_samplers = MAX2(pstip->num_textures, pstip->num_samplers);
 519    num_samplers = MAX2(num_samplers, pstip->fs->sampler_unit + 1);
 520
 521    /* plug in our sampler, texture */
 522    pstip->state.samplers[pstip->fs->sampler_unit] = pstip->sampler_cso;
 523    pipe_texture_reference(&pstip->state.textures[pstip->fs->sampler_unit],
 524                           pstip->texture);
 525
 526    assert(num_samplers <= PIPE_MAX_SAMPLERS);
 527
 528    draw->suspend_flushing = TRUE;
 529    pstip->driver_bind_sampler_states(pipe, num_samplers, pstip->state.samplers);
 530    pstip->driver_set_sampler_textures(pipe, num_samplers, pstip->state.textures);
 531    draw->suspend_flushing = FALSE;
 532
 533    /* now really draw first triangle */
 534    stage->tri = draw_pipe_passthrough_tri;
 535    stage->tri(stage, header);
 536 }
 537
 538
 539 static void
 540 pstip_flush(struct draw_stage *stage, unsigned flags)
 541 {
 542    struct draw_context *draw = stage->draw;
 543    struct pstip_stage *pstip = pstip_stage(stage);
 544    struct pipe_context *pipe = pstip->pipe;
 545
 546    stage->tri = pstip_first_tri;
 547    stage->next->flush( stage->next, flags );
 548
 549    /* restore original frag shader, texture, sampler state */
 550    draw->suspend_flushing = TRUE;
 551    pstip->driver_bind_fs_state(pipe, pstip->fs->driver_fs);
 552    pstip->driver_bind_sampler_states(pipe, pstip->num_samplers,
 553                                      pstip->state.samplers);
 554    pstip->driver_set_sampler_textures(pipe, pstip->num_textures,
 555                                       pstip->state.textures);
 556    draw->suspend_flushing = FALSE;
 557 }
 558
 559
 560 static void
 561 pstip_reset_stipple_counter(struct draw_stage *stage)
 562 {
 563    stage->next->reset_stipple_counter( stage->next );
 564 }
 565
 566
 567 static void
 568 pstip_destroy(struct draw_stage *stage)
 569 {
 570    struct pstip_stage *pstip = pstip_stage(stage);
 571    uint i;
 572
 573    for (i = 0; i < PIPE_MAX_SAMPLERS; i++) {
 574       pipe_texture_reference(&pstip->state.textures[i], NULL);
 575    }
 576
 577    pstip->pipe->delete_sampler_state(pstip->pipe, pstip->sampler_cso);
 578
 579    pipe_texture_reference(&pstip->texture, NULL);
 580
 581    draw_free_temp_verts( stage );
 582    FREE( stage );
 583 }
 584
 585
 586 static struct pstip_stage *
 587 draw_pstip_stage(struct draw_context *draw)
 588 {
 589    struct pstip_stage *pstip = CALLOC_STRUCT(pstip_stage);
 590
 591    draw_alloc_temp_verts( &pstip->stage, 8 );
 592
 593    pstip->stage.draw = draw;
 594    pstip->stage.name = "pstip";
 595    pstip->stage.next = NULL;
 596    pstip->stage.point = draw_pipe_passthrough_point;
 597    pstip->stage.line = draw_pipe_passthrough_line;
 598    pstip->stage.tri = pstip_first_tri;
 599    pstip->stage.flush = pstip_flush;
 600    pstip->stage.reset_stipple_counter = pstip_reset_stipple_counter;
 601    pstip->stage.destroy = pstip_destroy;
 602
 603    return pstip;
 604 }
 605
 606
 607 static struct pstip_stage *
 608 pstip_stage_from_pipe(struct pipe_context *pipe)
 609 {
 610    struct draw_context *draw = (struct draw_context *) pipe->draw;
 611    return pstip_stage(draw->pipeline.pstipple);
 612 }
 613
 614
 615 /**
 616  * This function overrides the driver's create_fs_state() function and
 617  * will typically be called by the state tracker.
 618  */
 619 static void *
 620 pstip_create_fs_state(struct pipe_context *pipe,
 621                        const struct pipe_shader_state *fs)
 622 {
 623    struct pstip_stage *pstip = pstip_stage_from_pipe(pipe);
 624    struct pstip_fragment_shader *aafs = CALLOC_STRUCT(pstip_fragment_shader);
 625
 626    if (aafs) {
 627       aafs->state = *fs;
 628
 629       /* pass-through */
 630       aafs->driver_fs = pstip->driver_create_fs_state(pstip->pipe, fs);
 631    }
 632
 633    return aafs;
 634 }
 635
 636
 637 static void
 638 pstip_bind_fs_state(struct pipe_context *pipe, void *fs)
 639 {
 640    struct pstip_stage *pstip = pstip_stage_from_pipe(pipe);
 641    struct pstip_fragment_shader *aafs = (struct pstip_fragment_shader *) fs;
 642    /* save current */
 643    pstip->fs = aafs;
 644    /* pass-through */
 645    pstip->driver_bind_fs_state(pstip->pipe,
 646                                (aafs ? aafs->driver_fs : NULL));
 647 }
 648
 649
 650 static void
 651 pstip_delete_fs_state(struct pipe_context *pipe, void *fs)
 652 {
 653    struct pstip_stage *pstip = pstip_stage_from_pipe(pipe);
 654    struct pstip_fragment_shader *aafs = (struct pstip_fragment_shader *) fs;
 655    /* pass-through */
 656    pstip->driver_delete_fs_state(pstip->pipe, aafs->driver_fs);
 657
 658    if (aafs->pstip_fs)
 659       pstip->driver_delete_fs_state(pstip->pipe, aafs->pstip_fs);
 660
 661    FREE(aafs);
 662 }
 663
 664
 665 static void
 666 pstip_bind_sampler_states(struct pipe_context *pipe,
 667                           unsigned num, void **sampler)
 668 {
 669    struct pstip_stage *pstip = pstip_stage_from_pipe(pipe);
 670    uint i;
 671
 672    /* save current */
 673    memcpy(pstip->state.samplers, sampler, num * sizeof(void *));
 674    for (i = num; i < PIPE_MAX_SAMPLERS; i++) {
 675       pstip->state.samplers[i] = NULL;
 676    }
 677
 678    pstip->num_samplers = num;
 679    /* pass-through */
 680    pstip->driver_bind_sampler_states(pstip->pipe, num, sampler);
 681 }
 682
 683
 684 static void
 685 pstip_set_sampler_textures(struct pipe_context *pipe,
 686                            unsigned num, struct pipe_texture **texture)
 687 {
 688    struct pstip_stage *pstip = pstip_stage_from_pipe(pipe);
 689    uint i;
 690
 691    /* save current */
 692    for (i = 0; i < num; i++) {
 693       pipe_texture_reference(&pstip->state.textures[i], texture[i]);
 694    }
 695    for (; i < PIPE_MAX_SAMPLERS; i++) {
 696       pipe_texture_reference(&pstip->state.textures[i], NULL);
 697    }
 698
 699    pstip->num_textures = num;
 700
 701    /* pass-through */
 702    pstip->driver_set_sampler_textures(pstip->pipe, num, texture);
 703 }
 704
 705
 706 static void
 707 pstip_set_polygon_stipple(struct pipe_context *pipe,
 708                           const struct pipe_poly_stipple *stipple)
 709 {
 710    struct pstip_stage *pstip = pstip_stage_from_pipe(pipe);
 711
 712    /* save current */
 713    pstip->state.stipple = stipple;
 714
 715    /* pass-through */
 716    pstip->driver_set_polygon_stipple(pstip->pipe, stipple);
 717
 718    pstip_update_texture(pstip);
 719 }
 720
 721
 722 /**
 723  * Called by drivers that want to install this polygon stipple stage
 724  * into the draw module's pipeline.  This will not be used if the
 725  * hardware has native support for polygon stipple.
 726  */
 727 boolean
 728 draw_install_pstipple_stage(struct draw_context *draw,
 729                             struct pipe_context *pipe)
 730 {
 731    struct pstip_stage *pstip;
 732
 733    pipe->draw = (void *) draw;
 734
 735    /*
 736     * Create / install pgon stipple drawing / prim stage
 737     */
 738    pstip = draw_pstip_stage( draw );
 739    if (pstip == NULL)
 740       goto fail;
 741
 742    draw->pipeline.pstipple = &pstip->stage;
 743
 744    pstip->pipe = pipe;
 745
 746    /* create special texture, sampler state */
 747    if (!pstip_create_texture(pstip))
 748       goto fail;
 749
 750    if (!pstip_create_sampler(pstip))
 751       goto fail;
 752
 753    /* save original driver functions */
 754    pstip->driver_create_fs_state = pipe->create_fs_state;
 755    pstip->driver_bind_fs_state = pipe->bind_fs_state;
 756    pstip->driver_delete_fs_state = pipe->delete_fs_state;
 757
 758    pstip->driver_bind_sampler_states = pipe->bind_fragment_sampler_states;
 759    pstip->driver_set_sampler_textures = pipe->set_fragment_sampler_textures;
 760    pstip->driver_set_polygon_stipple = pipe->set_polygon_stipple;
 761
 762    /* override the driver's functions */
 763    pipe->create_fs_state = pstip_create_fs_state;
 764    pipe->bind_fs_state = pstip_bind_fs_state;
 765    pipe->delete_fs_state = pstip_delete_fs_state;
 766
 767    pipe->bind_fragment_sampler_states = pstip_bind_sampler_states;
 768    pipe->set_fragment_sampler_textures = pstip_set_sampler_textures;
 769    pipe->set_polygon_stipple = pstip_set_polygon_stipple;
 770
 771    return TRUE;
 772
 773  fail:
 774    if (pstip)
 775       pstip->stage.destroy( &pstip->stage );
 776
 777    return FALSE;
 778 }