src/mesa/drivers/dri/i965/brw_clip_unfilled.c

   1 /*
   2  Copyright (C) Intel Corp.  2006.  All Rights Reserved.
   3  Intel funded Tungsten Graphics (http://www.tungstengraphics.com) to
   4  develop this 3D driver.
   5
   6  Permission is hereby granted, free of charge, to any person obtaining
   7  a 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, sublicense, 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
  16  portions of the Software.
  17
  18  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  19  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  20  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
  21  IN NO EVENT SHALL THE COPYRIGHT OWNER(S) AND/OR ITS SUPPLIERS BE
  22  LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  23  OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  24  WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  25
  26  **********************************************************************/
  27  /*
  28   * Authors:
  29   *   Keith Whitwell <keith@tungstengraphics.com>
  30   */
  31
  32 #include "main/glheader.h"
  33 #include "main/macros.h"
  34 #include "main/enums.h"
  35 #include "program/program.h"
  36
  37 #include "intel_batchbuffer.h"
  38
  39 #include "brw_defines.h"
  40 #include "brw_context.h"
  41 #include "brw_eu.h"
  42 #include "brw_clip.h"
  43
  44
  45
  46 /* This is performed against the original triangles, so no indirection
  47  * required:
  48 BZZZT!
  49  */
  50 static void compute_tri_direction( struct brw_clip_compile *c )
  51 {
  52    struct brw_compile *p = &c->func;
  53    struct brw_reg e = c->reg.tmp0;
  54    struct brw_reg f = c->reg.tmp1;
  55    struct brw_reg v0 = byte_offset(c->reg.vertex[0], c->offset[VERT_RESULT_HPOS]);
  56    struct brw_reg v1 = byte_offset(c->reg.vertex[1], c->offset[VERT_RESULT_HPOS]);
  57    struct brw_reg v2 = byte_offset(c->reg.vertex[2], c->offset[VERT_RESULT_HPOS]);
  58
  59
  60    struct brw_reg v0n = get_tmp(c);
  61    struct brw_reg v1n = get_tmp(c);
  62    struct brw_reg v2n = get_tmp(c);
  63
  64    /* Convert to NDC.
  65     * NOTE: We can't modify the original vertex coordinates,
  66     * as it may impact further operations.
  67     * So, we have to keep normalized coordinates in temp registers.
  68     *
  69     * TBD-KC
  70     * Try to optimize unnecessary MOV's.
  71     */
  72    brw_MOV(p, v0n, v0);
  73    brw_MOV(p, v1n, v1);
  74    brw_MOV(p, v2n, v2);
  75
  76    brw_clip_project_position(c, v0n);
  77    brw_clip_project_position(c, v1n);
  78    brw_clip_project_position(c, v2n);
  79
  80    /* Calculate the vectors of two edges of the triangle:
  81     */
  82    brw_ADD(p, e, v0n, negate(v2n));
  83    brw_ADD(p, f, v1n, negate(v2n));
  84
  85    /* Take their crossproduct:
  86     */
  87    brw_set_access_mode(p, BRW_ALIGN_16);
  88    brw_MUL(p, vec4(brw_null_reg()), brw_swizzle(e, 1,2,0,3),  brw_swizzle(f,2,0,1,3));
  89    brw_MAC(p, vec4(e),  negate(brw_swizzle(e, 2,0,1,3)), brw_swizzle(f,1,2,0,3));
  90    brw_set_access_mode(p, BRW_ALIGN_1);
  91
  92    brw_MUL(p, c->reg.dir, c->reg.dir, vec4(e));
  93 }
  94
  95
  96 static void cull_direction( struct brw_clip_compile *c )
  97 {
  98    struct brw_compile *p = &c->func;
  99    GLuint conditional;
 100
 101    assert (!(c->key.fill_ccw == CLIP_CULL &&
 102              c->key.fill_cw == CLIP_CULL));
 103
 104    if (c->key.fill_ccw == CLIP_CULL)
 105       conditional = BRW_CONDITIONAL_GE;
 106    else
 107       conditional = BRW_CONDITIONAL_L;
 108
 109    brw_CMP(p,
 110            vec1(brw_null_reg()),
 111            conditional,
 112            get_element(c->reg.dir, 2),
 113            brw_imm_f(0));
 114
 115    brw_IF(p, BRW_EXECUTE_1);
 116    {
 117       brw_clip_kill_thread(c);
 118    }
 119    brw_ENDIF(p);
 120 }
 121
 122
 123
 124 static void copy_bfc( struct brw_clip_compile *c )
 125 {
 126    struct brw_compile *p = &c->func;
 127    GLuint conditional;
 128
 129    /* Do we have any colors to copy?
 130     */
 131    if (!(c->offset[VERT_RESULT_COL0] && c->offset[VERT_RESULT_BFC0]) &&
 132        !(c->offset[VERT_RESULT_COL1] && c->offset[VERT_RESULT_BFC1]))
 133       return;
 134
 135    /* In some wierd degnerate cases we can end up testing the
 136     * direction twice, once for culling and once for bfc copying.  Oh
 137     * well, that's what you get for setting wierd GL state.
 138     */
 139    if (c->key.copy_bfc_ccw)
 140       conditional = BRW_CONDITIONAL_GE;
 141    else
 142       conditional = BRW_CONDITIONAL_L;
 143
 144    brw_CMP(p,
 145            vec1(brw_null_reg()),
 146            conditional,
 147            get_element(c->reg.dir, 2),
 148            brw_imm_f(0));
 149
 150    brw_IF(p, BRW_EXECUTE_1);
 151    {
 152       GLuint i;
 153
 154       for (i = 0; i < 3; i++) {
 155          if (c->offset[VERT_RESULT_COL0] && c->offset[VERT_RESULT_BFC0])
 156             brw_MOV(p,
 157                     byte_offset(c->reg.vertex[i], c->offset[VERT_RESULT_COL0]),
 158                     byte_offset(c->reg.vertex[i], c->offset[VERT_RESULT_BFC0]));
 159
 160          if (c->offset[VERT_RESULT_COL1] && c->offset[VERT_RESULT_BFC1])
 161             brw_MOV(p,
 162                     byte_offset(c->reg.vertex[i], c->offset[VERT_RESULT_COL1]),
 163                     byte_offset(c->reg.vertex[i], c->offset[VERT_RESULT_BFC1]));
 164       }
 165    }
 166    brw_ENDIF(p);
 167 }
 168
 169
 170
 171
 172 /*
 173   GLfloat iz    = 1.0 / dir.z;
 174   GLfloat ac    = dir.x * iz;
 175   GLfloat bc    = dir.y * iz;
 176   offset = ctx->Polygon.OffsetUnits * DEPTH_SCALE;
 177   offset += MAX2( abs(ac), abs(bc) ) * ctx->Polygon.OffsetFactor;
 178   offset *= MRD;
 179 */
 180 static void compute_offset( struct brw_clip_compile *c )
 181 {
 182    struct brw_compile *p = &c->func;
 183    struct brw_reg off = c->reg.offset;
 184    struct brw_reg dir = c->reg.dir;
 185
 186    brw_math_invert(p, get_element(off, 2), get_element(dir, 2));
 187    brw_MUL(p, vec2(off), dir, get_element(off, 2));
 188
 189    brw_CMP(p,
 190            vec1(brw_null_reg()),
 191            BRW_CONDITIONAL_GE,
 192            brw_abs(get_element(off, 0)),
 193            brw_abs(get_element(off, 1)));
 194
 195    brw_SEL(p, vec1(off), brw_abs(get_element(off, 0)), brw_abs(get_element(off, 1)));
 196    brw_set_predicate_control(p, BRW_PREDICATE_NONE);
 197
 198    brw_MUL(p, vec1(off), off, brw_imm_f(c->key.offset_factor));
 199    brw_ADD(p, vec1(off), off, brw_imm_f(c->key.offset_units));
 200 }
 201
 202
 203 static void merge_edgeflags( struct brw_clip_compile *c )
 204 {
 205    struct brw_compile *p = &c->func;
 206    struct brw_reg tmp0 = get_element_ud(c->reg.tmp0, 0);
 207
 208    brw_AND(p, tmp0, get_element_ud(c->reg.R0, 2), brw_imm_ud(PRIM_MASK));
 209    brw_CMP(p,
 210            vec1(brw_null_reg()),
 211            BRW_CONDITIONAL_EQ,
 212            tmp0,
 213            brw_imm_ud(_3DPRIM_POLYGON));
 214
 215    /* Get away with using reg.vertex because we know that this is not
 216     * a _3DPRIM_TRISTRIP_REVERSE:
 217     */
 218    brw_IF(p, BRW_EXECUTE_1);
 219    {
 220       brw_set_conditionalmod(p, BRW_CONDITIONAL_EQ);
 221       brw_AND(p, vec1(brw_null_reg()), get_element_ud(c->reg.R0, 2), brw_imm_ud(1<<8));
 222       brw_MOV(p, byte_offset(c->reg.vertex[0], c->offset[VERT_RESULT_EDGE]), brw_imm_f(0));
 223       brw_set_predicate_control(p, BRW_PREDICATE_NONE);
 224
 225       brw_set_conditionalmod(p, BRW_CONDITIONAL_EQ);
 226       brw_AND(p, vec1(brw_null_reg()), get_element_ud(c->reg.R0, 2), brw_imm_ud(1<<9));
 227       brw_MOV(p, byte_offset(c->reg.vertex[2], c->offset[VERT_RESULT_EDGE]), brw_imm_f(0));
 228       brw_set_predicate_control(p, BRW_PREDICATE_NONE);
 229    }
 230    brw_ENDIF(p);
 231 }
 232
 233
 234
 235 static void apply_one_offset( struct brw_clip_compile *c,
 236                           struct brw_indirect vert )
 237 {
 238    struct brw_compile *p = &c->func;
 239    struct brw_reg z = deref_1f(vert, c->ndc_offset +
 240                                2 * type_sz(BRW_REGISTER_TYPE_F));
 241
 242    brw_ADD(p, z, z, vec1(c->reg.offset));
 243 }
 244
 245
 246
 247 /***********************************************************************
 248  * Output clipped polygon as an unfilled primitive:
 249  */
 250 static void emit_lines(struct brw_clip_compile *c,
 251                        GLboolean do_offset)
 252 {
 253    struct brw_compile *p = &c->func;
 254    struct brw_instruction *loop;
 255    struct brw_indirect v0 = brw_indirect(0, 0);
 256    struct brw_indirect v1 = brw_indirect(1, 0);
 257    struct brw_indirect v0ptr = brw_indirect(2, 0);
 258    struct brw_indirect v1ptr = brw_indirect(3, 0);
 259
 260    /* Need a seperate loop for offset:
 261     */
 262    if (do_offset) {
 263       brw_MOV(p, c->reg.loopcount, c->reg.nr_verts);
 264       brw_MOV(p, get_addr_reg(v0ptr), brw_address(c->reg.inlist));
 265
 266       loop = brw_DO(p, BRW_EXECUTE_1);
 267       {
 268          brw_MOV(p, get_addr_reg(v0), deref_1uw(v0ptr, 0));
 269          brw_ADD(p, get_addr_reg(v0ptr), get_addr_reg(v0ptr), brw_imm_uw(2));
 270
 271          apply_one_offset(c, v0);
 272
 273          brw_set_conditionalmod(p, BRW_CONDITIONAL_G);
 274          brw_ADD(p, c->reg.loopcount, c->reg.loopcount, brw_imm_d(-1));
 275       }
 276       brw_WHILE(p, loop);
 277    }
 278
 279    /* v1ptr = &inlist[nr_verts]
 280     * *v1ptr = v0
 281     */
 282    brw_MOV(p, c->reg.loopcount, c->reg.nr_verts);
 283    brw_MOV(p, get_addr_reg(v0ptr), brw_address(c->reg.inlist));
 284    brw_ADD(p, get_addr_reg(v1ptr), get_addr_reg(v0ptr), retype(c->reg.nr_verts, BRW_REGISTER_TYPE_UW));
 285    brw_ADD(p, get_addr_reg(v1ptr), get_addr_reg(v1ptr), retype(c->reg.nr_verts, BRW_REGISTER_TYPE_UW));
 286    brw_MOV(p, deref_1uw(v1ptr, 0), deref_1uw(v0ptr, 0));
 287
 288    loop = brw_DO(p, BRW_EXECUTE_1);
 289    {
 290       brw_MOV(p, get_addr_reg(v0), deref_1uw(v0ptr, 0));
 291       brw_MOV(p, get_addr_reg(v1), deref_1uw(v0ptr, 2));
 292       brw_ADD(p, get_addr_reg(v0ptr), get_addr_reg(v0ptr), brw_imm_uw(2));
 293
 294       /* draw edge if edgeflag != 0 */
 295       brw_CMP(p,
 296               vec1(brw_null_reg()), BRW_CONDITIONAL_NZ,
 297               deref_1f(v0, c->offset[VERT_RESULT_EDGE]),
 298               brw_imm_f(0));
 299       brw_IF(p, BRW_EXECUTE_1);
 300       {
 301          brw_clip_emit_vue(c, v0, 1, 0, (_3DPRIM_LINESTRIP << 2) | R02_PRIM_START);
 302          brw_clip_emit_vue(c, v1, 1, 0, (_3DPRIM_LINESTRIP << 2) | R02_PRIM_END);
 303       }
 304       brw_ENDIF(p);
 305
 306       brw_set_conditionalmod(p, BRW_CONDITIONAL_NZ);
 307       brw_ADD(p, c->reg.loopcount, c->reg.loopcount, brw_imm_d(-1));
 308    }
 309    brw_WHILE(p, loop);
 310 }
 311
 312
 313
 314 static void emit_points(struct brw_clip_compile *c,
 315                         GLboolean do_offset )
 316 {
 317    struct brw_compile *p = &c->func;
 318    struct brw_instruction *loop;
 319
 320    struct brw_indirect v0 = brw_indirect(0, 0);
 321    struct brw_indirect v0ptr = brw_indirect(2, 0);
 322
 323    brw_MOV(p, c->reg.loopcount, c->reg.nr_verts);
 324    brw_MOV(p, get_addr_reg(v0ptr), brw_address(c->reg.inlist));
 325
 326    loop = brw_DO(p, BRW_EXECUTE_1);
 327    {
 328       brw_MOV(p, get_addr_reg(v0), deref_1uw(v0ptr, 0));
 329       brw_ADD(p, get_addr_reg(v0ptr), get_addr_reg(v0ptr), brw_imm_uw(2));
 330
 331       /* draw if edgeflag != 0
 332        */
 333       brw_CMP(p,
 334               vec1(brw_null_reg()), BRW_CONDITIONAL_NZ,
 335               deref_1f(v0, c->offset[VERT_RESULT_EDGE]),
 336               brw_imm_f(0));
 337       brw_IF(p, BRW_EXECUTE_1);
 338       {
 339          if (do_offset)
 340             apply_one_offset(c, v0);
 341
 342          brw_clip_emit_vue(c, v0, 1, 0, (_3DPRIM_POINTLIST << 2) | R02_PRIM_START | R02_PRIM_END);
 343       }
 344       brw_ENDIF(p);
 345
 346       brw_set_conditionalmod(p, BRW_CONDITIONAL_NZ);
 347       brw_ADD(p, c->reg.loopcount, c->reg.loopcount, brw_imm_d(-1));
 348    }
 349    brw_WHILE(p, loop);
 350 }
 351
 352
 353
 354
 355
 356
 357
 358 static void emit_primitives( struct brw_clip_compile *c,
 359                              GLuint mode,
 360                              GLboolean do_offset )
 361 {
 362    switch (mode) {
 363    case CLIP_FILL:
 364       brw_clip_tri_emit_polygon(c);
 365       break;
 366
 367    case CLIP_LINE:
 368       emit_lines(c, do_offset);
 369       break;
 370
 371    case CLIP_POINT:
 372       emit_points(c, do_offset);
 373       break;
 374
 375    case CLIP_CULL:
 376       assert(0);
 377       break;
 378    }
 379 }
 380
 381
 382
 383 static void emit_unfilled_primitives( struct brw_clip_compile *c )
 384 {
 385    struct brw_compile *p = &c->func;
 386
 387    /* Direction culling has already been done.
 388     */
 389    if (c->key.fill_ccw != c->key.fill_cw &&
 390        c->key.fill_ccw != CLIP_CULL &&
 391        c->key.fill_cw != CLIP_CULL)
 392    {
 393       brw_CMP(p,
 394               vec1(brw_null_reg()),
 395               BRW_CONDITIONAL_GE,
 396               get_element(c->reg.dir, 2),
 397               brw_imm_f(0));
 398
 399       brw_IF(p, BRW_EXECUTE_1);
 400       {
 401          emit_primitives(c, c->key.fill_ccw, c->key.offset_ccw);
 402       }
 403       brw_ELSE(p);
 404       {
 405          emit_primitives(c, c->key.fill_cw, c->key.offset_cw);
 406       }
 407       brw_ENDIF(p);
 408    }
 409    else if (c->key.fill_cw != CLIP_CULL) {
 410       emit_primitives(c, c->key.fill_cw, c->key.offset_cw);
 411    }
 412    else if (c->key.fill_ccw != CLIP_CULL) {
 413       emit_primitives(c, c->key.fill_ccw, c->key.offset_ccw);
 414    }
 415 }
 416
 417
 418
 419
 420 static void check_nr_verts( struct brw_clip_compile *c )
 421 {
 422    struct brw_compile *p = &c->func;
 423
 424    brw_CMP(p, vec1(brw_null_reg()), BRW_CONDITIONAL_L, c->reg.nr_verts, brw_imm_d(3));
 425    brw_IF(p, BRW_EXECUTE_1);
 426    {
 427       brw_clip_kill_thread(c);
 428    }
 429    brw_ENDIF(p);
 430 }
 431
 432
 433 void brw_emit_unfilled_clip( struct brw_clip_compile *c )
 434 {
 435    struct brw_compile *p = &c->func;
 436
 437    c->need_direction = ((c->key.offset_ccw || c->key.offset_cw) ||
 438                         (c->key.fill_ccw != c->key.fill_cw) ||
 439                         c->key.fill_ccw == CLIP_CULL ||
 440                         c->key.fill_cw == CLIP_CULL ||
 441                         c->key.copy_bfc_cw ||
 442                         c->key.copy_bfc_ccw);
 443
 444    brw_clip_tri_alloc_regs(c, 3 + c->key.nr_userclip + 6);
 445    brw_clip_tri_init_vertices(c);
 446    brw_clip_init_ff_sync(c);
 447
 448    assert(c->offset[VERT_RESULT_EDGE]);
 449
 450    if (c->key.fill_ccw == CLIP_CULL &&
 451        c->key.fill_cw == CLIP_CULL) {
 452       brw_clip_kill_thread(c);
 453       return;
 454    }
 455
 456    merge_edgeflags(c);
 457
 458    /* Need to use the inlist indirection here:
 459     */
 460    if (c->need_direction)
 461       compute_tri_direction(c);
 462
 463    if (c->key.fill_ccw == CLIP_CULL ||
 464        c->key.fill_cw == CLIP_CULL)
 465       cull_direction(c);
 466
 467    if (c->key.offset_ccw ||
 468        c->key.offset_cw)
 469       compute_offset(c);
 470
 471    if (c->key.copy_bfc_ccw ||
 472        c->key.copy_bfc_cw)
 473       copy_bfc(c);
 474
 475    /* Need to do this whether we clip or not:
 476     */
 477    if (c->key.do_flat_shading)
 478       brw_clip_tri_flat_shade(c);
 479
 480    brw_clip_init_clipmask(c);
 481    brw_CMP(p, vec1(brw_null_reg()), BRW_CONDITIONAL_NZ, c->reg.planemask, brw_imm_ud(0));
 482    brw_IF(p, BRW_EXECUTE_1);
 483    {
 484       brw_clip_init_planes(c);
 485       brw_clip_tri(c);
 486       check_nr_verts(c);
 487    }
 488    brw_ENDIF(p);
 489
 490    emit_unfilled_primitives(c);
 491    brw_clip_kill_thread(c);
 492 }
 493
 494
 495