sp_tex_sample.c revision 6acd63a4980951727939c0dd545a0324965b3834
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 * Texture sampling 30 * 31 * Authors: 32 * Brian Paul 33 */ 34 35#include "sp_context.h" 36#include "sp_headers.h" 37#include "sp_surface.h" 38#include "sp_tex_sample.h" 39#include "sp_tile_cache.h" 40#include "pipe/p_context.h" 41#include "pipe/p_defines.h" 42#include "pipe/p_util.h" 43#include "tgsi/exec/tgsi_exec.h" 44 45 46/* 47 * Note, the FRAC macro has to work perfectly. Otherwise you'll sometimes 48 * see 1-pixel bands of improperly weighted linear-filtered textures. 49 * The tests/texwrap.c demo is a good test. 50 * Also note, FRAC(x) doesn't truly return the fractional part of x for x < 0. 51 * Instead, if x < 0 then FRAC(x) = 1 - true_frac(x). 52 */ 53#define FRAC(f) ((f) - ifloor(f)) 54 55 56/** 57 * Linear interpolation macro 58 */ 59#define LERP(T, A, B) ( (A) + (T) * ((B) - (A)) ) 60 61 62/** 63 * Do 2D/biliner interpolation of float values. 64 * v00, v10, v01 and v11 are typically four texture samples in a square/box. 65 * a and b are the horizontal and vertical interpolants. 66 * It's important that this function is inlined when compiled with 67 * optimization! If we find that's not true on some systems, convert 68 * to a macro. 69 */ 70static INLINE float 71lerp_2d(float a, float b, 72 float v00, float v10, float v01, float v11) 73{ 74 const float temp0 = LERP(a, v00, v10); 75 const float temp1 = LERP(a, v01, v11); 76 return LERP(b, temp0, temp1); 77} 78 79 80/** 81 * If A is a signed integer, A % B doesn't give the right value for A < 0 82 * (in terms of texture repeat). Just casting to unsigned fixes that. 83 */ 84#define REMAINDER(A, B) ((unsigned) (A) % (unsigned) (B)) 85 86 87/** 88 * Apply texture coord wrapping mode and return integer texture index. 89 * \param wrapMode PIPE_TEX_WRAP_x 90 * \param s the texcoord 91 * \param size the texture image size 92 * \return integer texture index 93 */ 94static INLINE int 95nearest_texcoord(unsigned wrapMode, float s, unsigned size) 96{ 97 int i; 98 switch (wrapMode) { 99 case PIPE_TEX_WRAP_REPEAT: 100 /* s limited to [0,1) */ 101 /* i limited to [0,size-1] */ 102 i = ifloor(s * size); 103 i = REMAINDER(i, size); 104 return i; 105 case PIPE_TEX_WRAP_CLAMP: 106 /* s limited to [0,1] */ 107 /* i limited to [0,size-1] */ 108 if (s <= 0.0F) 109 i = 0; 110 else if (s >= 1.0F) 111 i = size - 1; 112 else 113 i = ifloor(s * size); 114 return i; 115 case PIPE_TEX_WRAP_CLAMP_TO_EDGE: 116 { 117 /* s limited to [min,max] */ 118 /* i limited to [0, size-1] */ 119 const float min = 1.0F / (2.0F * size); 120 const float max = 1.0F - min; 121 if (s < min) 122 i = 0; 123 else if (s > max) 124 i = size - 1; 125 else 126 i = ifloor(s * size); 127 } 128 return i; 129 case PIPE_TEX_WRAP_CLAMP_TO_BORDER: 130 { 131 /* s limited to [min,max] */ 132 /* i limited to [-1, size] */ 133 const float min = -1.0F / (2.0F * size); 134 const float max = 1.0F - min; 135 if (s <= min) 136 i = -1; 137 else if (s >= max) 138 i = size; 139 else 140 i = ifloor(s * size); 141 } 142 return i; 143 case PIPE_TEX_WRAP_MIRROR_REPEAT: 144 { 145 const float min = 1.0F / (2.0F * size); 146 const float max = 1.0F - min; 147 const int flr = ifloor(s); 148 float u; 149 if (flr & 1) 150 u = 1.0F - (s - (float) flr); 151 else 152 u = s - (float) flr; 153 if (u < min) 154 i = 0; 155 else if (u > max) 156 i = size - 1; 157 else 158 i = ifloor(u * size); 159 } 160 return i; 161 case PIPE_TEX_WRAP_MIRROR_CLAMP: 162 { 163 /* s limited to [0,1] */ 164 /* i limited to [0,size-1] */ 165 const float u = FABSF(s); 166 if (u <= 0.0F) 167 i = 0; 168 else if (u >= 1.0F) 169 i = size - 1; 170 else 171 i = ifloor(u * size); 172 } 173 return i; 174 case PIPE_TEX_WRAP_MIRROR_CLAMP_TO_EDGE: 175 { 176 /* s limited to [min,max] */ 177 /* i limited to [0, size-1] */ 178 const float min = 1.0F / (2.0F * size); 179 const float max = 1.0F - min; 180 const float u = FABSF(s); 181 if (u < min) 182 i = 0; 183 else if (u > max) 184 i = size - 1; 185 else 186 i = ifloor(u * size); 187 } 188 return i; 189 case PIPE_TEX_WRAP_MIRROR_CLAMP_TO_BORDER: 190 { 191 /* s limited to [min,max] */ 192 /* i limited to [0, size-1] */ 193 const float min = -1.0F / (2.0F * size); 194 const float max = 1.0F - min; 195 const float u = FABSF(s); 196 if (u < min) 197 i = -1; 198 else if (u > max) 199 i = size; 200 else 201 i = ifloor(u * size); 202 } 203 return i; 204 default: 205 assert(0); 206 return 0; 207 } 208} 209 210 211/** 212 * Used to compute texel locations for linear sampling. 213 * \param wrapMode PIPE_TEX_WRAP_x 214 * \param s the texcoord 215 * \param size the texture image size 216 * \param i0 returns first texture index 217 * \param i1 returns second texture index (usually *i0 + 1) 218 * \param a returns blend factor/weight between texture indexes 219 */ 220static INLINE void 221linear_texcoord(unsigned wrapMode, float s, unsigned size, 222 int *i0, int *i1, float *a) 223{ 224 float u; 225 switch (wrapMode) { 226 case PIPE_TEX_WRAP_REPEAT: 227 u = s * size - 0.5F; 228 *i0 = REMAINDER(ifloor(u), size); 229 *i1 = REMAINDER(*i0 + 1, size); 230 break; 231 case PIPE_TEX_WRAP_CLAMP: 232 if (s <= 0.0F) 233 u = 0.0F; 234 else if (s >= 1.0F) 235 u = (float) size; 236 else 237 u = s * size; 238 u -= 0.5F; 239 *i0 = ifloor(u); 240 *i1 = *i0 + 1; 241 break; 242 case PIPE_TEX_WRAP_CLAMP_TO_EDGE: 243 if (s <= 0.0F) 244 u = 0.0F; 245 else if (s >= 1.0F) 246 u = (float) size; 247 else 248 u = s * size; 249 u -= 0.5F; 250 *i0 = ifloor(u); 251 *i1 = *i0 + 1; 252 if (*i0 < 0) 253 *i0 = 0; 254 if (*i1 >= (int) size) 255 *i1 = size - 1; 256 break; 257 case PIPE_TEX_WRAP_CLAMP_TO_BORDER: 258 { 259 const float min = -1.0F / (2.0F * size); 260 const float max = 1.0F - min; 261 if (s <= min) 262 u = min * size; 263 else if (s >= max) 264 u = max * size; 265 else 266 u = s * size; 267 u -= 0.5F; 268 *i0 = ifloor(u); 269 *i1 = *i0 + 1; 270 } 271 break; 272 case PIPE_TEX_WRAP_MIRROR_REPEAT: 273 { 274 const int flr = ifloor(s); 275 if (flr & 1) 276 u = 1.0F - (s - (float) flr); 277 else 278 u = s - (float) flr; 279 u = (u * size) - 0.5F; 280 *i0 = ifloor(u); 281 *i1 = *i0 + 1; 282 if (*i0 < 0) 283 *i0 = 0; 284 if (*i1 >= (int) size) 285 *i1 = size - 1; 286 } 287 break; 288 case PIPE_TEX_WRAP_MIRROR_CLAMP: 289 u = FABSF(s); 290 if (u >= 1.0F) 291 u = (float) size; 292 else 293 u *= size; 294 u -= 0.5F; 295 *i0 = ifloor(u); 296 *i1 = *i0 + 1; 297 break; 298 case PIPE_TEX_WRAP_MIRROR_CLAMP_TO_EDGE: 299 u = FABSF(s); 300 if (u >= 1.0F) 301 u = (float) size; 302 else 303 u *= size; 304 u -= 0.5F; 305 *i0 = ifloor(u); 306 *i1 = *i0 + 1; 307 if (*i0 < 0) 308 *i0 = 0; 309 if (*i1 >= (int) size) 310 *i1 = size - 1; 311 break; 312 case PIPE_TEX_WRAP_MIRROR_CLAMP_TO_BORDER: 313 { 314 const float min = -1.0F / (2.0F * size); 315 const float max = 1.0F - min; 316 u = FABSF(s); 317 if (u <= min) 318 u = min * size; 319 else if (u >= max) 320 u = max * size; 321 else 322 u *= size; 323 u -= 0.5F; 324 *i0 = ifloor(u); 325 *i1 = *i0 + 1; 326 } 327 break; 328 default: 329 assert(0); 330 } 331 *a = FRAC(u); 332} 333 334 335static unsigned 336choose_cube_face(float rx, float ry, float rz, float *newS, float *newT) 337{ 338 /* 339 major axis 340 direction target sc tc ma 341 ---------- ------------------------------- --- --- --- 342 +rx TEXTURE_CUBE_MAP_POSITIVE_X_EXT -rz -ry rx 343 -rx TEXTURE_CUBE_MAP_NEGATIVE_X_EXT +rz -ry rx 344 +ry TEXTURE_CUBE_MAP_POSITIVE_Y_EXT +rx +rz ry 345 -ry TEXTURE_CUBE_MAP_NEGATIVE_Y_EXT +rx -rz ry 346 +rz TEXTURE_CUBE_MAP_POSITIVE_Z_EXT +rx -ry rz 347 -rz TEXTURE_CUBE_MAP_NEGATIVE_Z_EXT -rx -ry rz 348 */ 349 const float arx = FABSF(rx), ary = FABSF(ry), arz = FABSF(rz); 350 unsigned face; 351 float sc, tc, ma; 352 353 if (arx > ary && arx > arz) { 354 if (rx >= 0.0F) { 355 face = PIPE_TEX_FACE_POS_X; 356 sc = -rz; 357 tc = -ry; 358 ma = arx; 359 } 360 else { 361 face = PIPE_TEX_FACE_NEG_X; 362 sc = rz; 363 tc = -ry; 364 ma = arx; 365 } 366 } 367 else if (ary > arx && ary > arz) { 368 if (ry >= 0.0F) { 369 face = PIPE_TEX_FACE_POS_Y; 370 sc = rx; 371 tc = rz; 372 ma = ary; 373 } 374 else { 375 face = PIPE_TEX_FACE_NEG_Y; 376 sc = rx; 377 tc = -rz; 378 ma = ary; 379 } 380 } 381 else { 382 if (rz > 0.0F) { 383 face = PIPE_TEX_FACE_POS_Z; 384 sc = rx; 385 tc = -ry; 386 ma = arz; 387 } 388 else { 389 face = PIPE_TEX_FACE_NEG_Z; 390 sc = -rx; 391 tc = -ry; 392 ma = arz; 393 } 394 } 395 396 *newS = ( sc / ma + 1.0F ) * 0.5F; 397 *newT = ( tc / ma + 1.0F ) * 0.5F; 398 399 return face; 400} 401 402 403/** 404 * Examine the quad's texture coordinates to compute the partial 405 * derivatives w.r.t X and Y, then compute lambda (level of detail). 406 * 407 * This is only done for fragment shaders, not vertex shaders. 408 */ 409static float 410compute_lambda(struct tgsi_sampler *sampler, 411 const float s[QUAD_SIZE], 412 const float t[QUAD_SIZE], 413 const float p[QUAD_SIZE], 414 float lodbias) 415{ 416 float rho, lambda; 417 418 assert(s); 419 { 420 float dsdx = s[QUAD_BOTTOM_RIGHT] - s[QUAD_BOTTOM_LEFT]; 421 float dsdy = s[QUAD_TOP_LEFT] - s[QUAD_BOTTOM_LEFT]; 422 dsdx = FABSF(dsdx); 423 dsdy = FABSF(dsdy); 424 rho = MAX2(dsdx, dsdy); 425 if (sampler->state->normalized_coords) 426 rho *= sampler->texture->width[0]; 427 } 428 if (t) { 429 float dtdx = t[QUAD_BOTTOM_RIGHT] - t[QUAD_BOTTOM_LEFT]; 430 float dtdy = t[QUAD_TOP_LEFT] - t[QUAD_BOTTOM_LEFT]; 431 float max; 432 dtdx = FABSF(dtdx); 433 dtdy = FABSF(dtdy); 434 max = MAX2(dtdx, dtdy); 435 if (sampler->state->normalized_coords) 436 max *= sampler->texture->height[0]; 437 rho = MAX2(rho, max); 438 } 439 if (p) { 440 float dpdx = p[QUAD_BOTTOM_RIGHT] - p[QUAD_BOTTOM_LEFT]; 441 float dpdy = p[QUAD_TOP_LEFT] - p[QUAD_BOTTOM_LEFT]; 442 float max; 443 dpdx = FABSF(dpdx); 444 dpdy = FABSF(dpdy); 445 max = MAX2(dpdx, dpdy); 446 if (sampler->state->normalized_coords) 447 max *= sampler->texture->depth[0]; 448 rho = MAX2(rho, max); 449 } 450 451 lambda = LOG2(rho); 452 lambda += lodbias + sampler->state->lod_bias; 453 lambda = CLAMP(lambda, sampler->state->min_lod, sampler->state->max_lod); 454 455 return lambda; 456} 457 458 459/** 460 * Do several things here: 461 * 1. Compute lambda from the texcoords, if needed 462 * 2. Determine if we're minifying or magnifying 463 * 3. If minifying, choose mipmap levels 464 * 4. Return image filter to use within mipmap images 465 */ 466static void 467choose_mipmap_levels(struct tgsi_sampler *sampler, 468 const float s[QUAD_SIZE], 469 const float t[QUAD_SIZE], 470 const float p[QUAD_SIZE], 471 float lodbias, 472 unsigned *level0, unsigned *level1, float *levelBlend, 473 unsigned *imgFilter) 474{ 475 if (sampler->state->min_mip_filter == PIPE_TEX_MIPFILTER_NONE) { 476 /* no mipmap selection needed */ 477 *imgFilter = sampler->state->mag_img_filter; 478 *level0 = *level1 = (int) sampler->state->min_lod; 479 } 480 else { 481 float lambda; 482 483 if (1) 484 /* fragment shader */ 485 lambda = compute_lambda(sampler, s, t, p, lodbias); 486 else 487 /* vertex shader */ 488 lambda = lodbias; /* not really a bias, but absolute LOD */ 489 490 if (lambda < 0.0) { /* XXX threshold depends on the filter */ 491 /* magnifying */ 492 *imgFilter = sampler->state->mag_img_filter; 493 *level0 = *level1 = 0; 494 } 495 else { 496 /* minifying */ 497 *imgFilter = sampler->state->min_img_filter; 498 499 /* choose mipmap level(s) and compute the blend factor between them */ 500 if (sampler->state->min_mip_filter == PIPE_TEX_MIPFILTER_NEAREST) { 501 /* Nearest mipmap level */ 502 const int lvl = (int) (lambda + 0.5); 503 *level0 = 504 *level1 = CLAMP(lvl, 0, (int) sampler->texture->last_level); 505 } 506 else { 507 /* Linear interpolation between mipmap levels */ 508 const int lvl = (int) lambda; 509 *level0 = CLAMP(lvl, 0, (int) sampler->texture->last_level); 510 *level1 = CLAMP(lvl + 1, 0, (int) sampler->texture->last_level); 511 *levelBlend = FRAC(lambda); /* blending weight between levels */ 512 } 513 } 514 } 515} 516 517 518/** 519 * Get a texel from a texture, using the texture tile cache. 520 * 521 * \param face the cube face in 0..5 522 * \param level the mipmap level 523 * \param x the x coord of texel within 2D image 524 * \param y the y coord of texel within 2D image 525 * \param z which slice of a 3D texture 526 * \param rgba the quad to put the texel/color into 527 * \param j which element of the rgba quad to write to 528 * 529 * XXX maybe move this into sp_tile_cache.c and merge with the 530 * sp_get_cached_tile_tex() function. Also, get 4 texels instead of 1... 531 */ 532static void 533get_texel(struct tgsi_sampler *sampler, 534 unsigned face, unsigned level, int x, int y, int z, 535 float rgba[NUM_CHANNELS][QUAD_SIZE], unsigned j) 536{ 537 const int tx = x % TILE_SIZE; 538 const int ty = y % TILE_SIZE; 539 const struct softpipe_cached_tile *tile 540 = sp_get_cached_tile_tex(sampler->pipe, sampler->cache, 541 x, y, z, face, level); 542 rgba[0][j] = tile->data.color[ty][tx][0]; 543 rgba[1][j] = tile->data.color[ty][tx][1]; 544 rgba[2][j] = tile->data.color[ty][tx][2]; 545 rgba[3][j] = tile->data.color[ty][tx][3]; 546} 547 548 549/** 550 * Compare texcoord 'p' (aka R) against texture value 'rgba[0]' 551 * When we sampled the depth texture, the depth value was put into all 552 * RGBA channels. We look at the red channel here. 553 */ 554static INLINE void 555shadow_compare(uint compare_func, 556 float rgba[NUM_CHANNELS][QUAD_SIZE], 557 const float p[QUAD_SIZE], 558 uint j) 559{ 560 int k; 561 switch (compare_func) { 562 case PIPE_FUNC_LESS: 563 k = p[j] < rgba[0][j]; 564 break; 565 case PIPE_FUNC_LEQUAL: 566 k = p[j] <= rgba[0][j]; 567 break; 568 case PIPE_FUNC_GREATER: 569 k = p[j] > rgba[0][j]; 570 break; 571 case PIPE_FUNC_GEQUAL: 572 k = p[j] >= rgba[0][j]; 573 break; 574 case PIPE_FUNC_EQUAL: 575 k = p[j] == rgba[0][j]; 576 break; 577 case PIPE_FUNC_NOTEQUAL: 578 k = p[j] != rgba[0][j]; 579 break; 580 case PIPE_FUNC_ALWAYS: 581 k = 1; 582 break; 583 case PIPE_FUNC_NEVER: 584 k = 0; 585 break; 586 default: 587 assert(0); 588 } 589 590 rgba[0][j] = rgba[1][j] = rgba[2][j] = (float) k; 591} 592 593 594/** 595 * Common code for sampling 1D/2D/cube textures. 596 * Could probably extend for 3D... 597 */ 598static void 599sp_get_samples_2d_common(struct tgsi_sampler *sampler, 600 const float s[QUAD_SIZE], 601 const float t[QUAD_SIZE], 602 const float p[QUAD_SIZE], 603 float lodbias, 604 float rgba[NUM_CHANNELS][QUAD_SIZE], 605 const unsigned faces[4]) 606{ 607 const uint compare_func = sampler->state->compare_func; 608 unsigned level0, level1, j, imgFilter; 609 int width, height; 610 float levelBlend; 611 612 choose_mipmap_levels(sampler, s, t, p, lodbias, 613 &level0, &level1, &levelBlend, &imgFilter); 614 615 if (sampler->state->normalized_coords) { 616 width = sampler->texture->width[level0]; 617 height = sampler->texture->height[level0]; 618 } 619 else { 620 width = height = 1; 621 } 622 623 assert(width > 0); 624 625 switch (imgFilter) { 626 case PIPE_TEX_FILTER_NEAREST: 627 for (j = 0; j < QUAD_SIZE; j++) { 628 int x = nearest_texcoord(sampler->state->wrap_s, s[j], width); 629 int y = nearest_texcoord(sampler->state->wrap_t, t[j], height); 630 get_texel(sampler, faces[j], level0, x, y, 0, rgba, j); 631 if (sampler->state->compare_mode == PIPE_TEX_COMPARE_R_TO_TEXTURE) { 632 shadow_compare(compare_func, rgba, p, j); 633 } 634 635 if (level0 != level1) { 636 /* get texels from second mipmap level and blend */ 637 float rgba2[4][4]; 638 unsigned c; 639 x = x / 2; 640 y = y / 2; 641 get_texel(sampler, faces[j], level1, x, y, 0, rgba2, j); 642 if (sampler->state->compare_mode == PIPE_TEX_COMPARE_R_TO_TEXTURE){ 643 shadow_compare(compare_func, rgba2, p, j); 644 } 645 646 for (c = 0; c < NUM_CHANNELS; c++) { 647 rgba[c][j] = LERP(levelBlend, rgba[c][j], rgba2[c][j]); 648 } 649 } 650 } 651 break; 652 case PIPE_TEX_FILTER_LINEAR: 653 for (j = 0; j < QUAD_SIZE; j++) { 654 float tx[4][4], a, b; 655 int x0, y0, x1, y1, c; 656 linear_texcoord(sampler->state->wrap_s, s[j], width, &x0, &x1, &a); 657 linear_texcoord(sampler->state->wrap_t, t[j], height, &y0, &y1, &b); 658 get_texel(sampler, faces[j], level0, x0, y0, 0, tx, 0); 659 get_texel(sampler, faces[j], level0, x1, y0, 0, tx, 1); 660 get_texel(sampler, faces[j], level0, x0, y1, 0, tx, 2); 661 get_texel(sampler, faces[j], level0, x1, y1, 0, tx, 3); 662 if (sampler->state->compare_mode == PIPE_TEX_COMPARE_R_TO_TEXTURE) { 663 shadow_compare(compare_func, tx, p, 0); 664 shadow_compare(compare_func, tx, p, 1); 665 shadow_compare(compare_func, tx, p, 2); 666 shadow_compare(compare_func, tx, p, 3); 667 } 668 669 for (c = 0; c < 4; c++) { 670 rgba[c][j] = lerp_2d(a, b, tx[c][0], tx[c][1], tx[c][2], tx[c][3]); 671 } 672 673 if (level0 != level1) { 674 /* get texels from second mipmap level and blend */ 675 float rgba2[4][4]; 676 x0 = x0 / 2; 677 y0 = y0 / 2; 678 x1 = x1 / 2; 679 y1 = y1 / 2; 680 get_texel(sampler, faces[j], level1, x0, y0, 0, tx, 0); 681 get_texel(sampler, faces[j], level1, x1, y0, 0, tx, 1); 682 get_texel(sampler, faces[j], level1, x0, y1, 0, tx, 2); 683 get_texel(sampler, faces[j], level1, x1, y1, 0, tx, 3); 684 if (sampler->state->compare_mode == PIPE_TEX_COMPARE_R_TO_TEXTURE){ 685 shadow_compare(compare_func, tx, p, 0); 686 shadow_compare(compare_func, tx, p, 1); 687 shadow_compare(compare_func, tx, p, 2); 688 shadow_compare(compare_func, tx, p, 3); 689 } 690 691 for (c = 0; c < 4; c++) { 692 rgba2[c][j] = lerp_2d(a, b, 693 tx[c][0], tx[c][1], tx[c][2], tx[c][3]); 694 } 695 696 for (c = 0; c < NUM_CHANNELS; c++) { 697 rgba[c][j] = LERP(levelBlend, rgba[c][j], rgba2[c][j]); 698 } 699 } 700 } 701 break; 702 default: 703 assert(0); 704 } 705} 706 707 708static void 709sp_get_samples_1d(struct tgsi_sampler *sampler, 710 const float s[QUAD_SIZE], 711 const float t[QUAD_SIZE], 712 const float p[QUAD_SIZE], 713 float lodbias, 714 float rgba[NUM_CHANNELS][QUAD_SIZE]) 715{ 716 static const unsigned faces[4] = {0, 0, 0, 0}; 717 static const float tzero[4] = {0, 0, 0, 0}; 718 sp_get_samples_2d_common(sampler, s, tzero, NULL, lodbias, rgba, faces); 719} 720 721 722static void 723sp_get_samples_2d(struct tgsi_sampler *sampler, 724 const float s[QUAD_SIZE], 725 const float t[QUAD_SIZE], 726 const float p[QUAD_SIZE], 727 float lodbias, 728 float rgba[NUM_CHANNELS][QUAD_SIZE]) 729{ 730 static const unsigned faces[4] = {0, 0, 0, 0}; 731 sp_get_samples_2d_common(sampler, s, t, p, lodbias, rgba, faces); 732} 733 734 735static void 736sp_get_samples_3d(struct tgsi_sampler *sampler, 737 const float s[QUAD_SIZE], 738 const float t[QUAD_SIZE], 739 const float p[QUAD_SIZE], 740 float lodbias, 741 float rgba[NUM_CHANNELS][QUAD_SIZE]) 742{ 743 /* get/map pipe_surfaces corresponding to 3D tex slices */ 744 unsigned level0, level1, j, imgFilter; 745 int width, height, depth; 746 float levelBlend; 747 const uint face = 0; 748 749 choose_mipmap_levels(sampler, s, t, p, lodbias, 750 &level0, &level1, &levelBlend, &imgFilter); 751 752 if (sampler->state->normalized_coords) { 753 width = sampler->texture->width[level0]; 754 height = sampler->texture->height[level0]; 755 depth = sampler->texture->depth[level0]; 756 } 757 else { 758 width = height = depth = 1; 759 } 760 761 assert(width > 0); 762 assert(height > 0); 763 assert(depth > 0); 764 765 switch (imgFilter) { 766 case PIPE_TEX_FILTER_NEAREST: 767 for (j = 0; j < QUAD_SIZE; j++) { 768 int x = nearest_texcoord(sampler->state->wrap_s, s[j], width); 769 int y = nearest_texcoord(sampler->state->wrap_t, t[j], height); 770 int z = nearest_texcoord(sampler->state->wrap_r, p[j], depth); 771 get_texel(sampler, face, level0, x, y, z, rgba, j); 772 773 if (level0 != level1) { 774 /* get texels from second mipmap level and blend */ 775 float rgba2[4][4]; 776 unsigned c; 777 x /= 2; 778 y /= 2; 779 z /= 2; 780 get_texel(sampler, face, level1, x, y, z, rgba2, j); 781 for (c = 0; c < NUM_CHANNELS; c++) { 782 rgba[c][j] = LERP(levelBlend, rgba2[c][j], rgba[c][j]); 783 } 784 } 785 } 786 break; 787 case PIPE_TEX_FILTER_LINEAR: 788 for (j = 0; j < QUAD_SIZE; j++) { 789 float texel0[4][4], texel1[4][4]; 790 float xw, yw, zw; /* interpolation weights */ 791 int x0, x1, y0, y1, z0, z1, c; 792 linear_texcoord(sampler->state->wrap_s, s[j], width, &x0, &x1, &xw); 793 linear_texcoord(sampler->state->wrap_t, t[j], height, &y0, &y1, &yw); 794 linear_texcoord(sampler->state->wrap_r, p[j], depth, &z0, &z1, &zw); 795 get_texel(sampler, face, level0, x0, y0, z0, texel0, 0); 796 get_texel(sampler, face, level0, x1, y0, z0, texel0, 1); 797 get_texel(sampler, face, level0, x0, y1, z0, texel0, 2); 798 get_texel(sampler, face, level0, x1, y1, z0, texel0, 3); 799 get_texel(sampler, face, level0, x0, y0, z1, texel1, 0); 800 get_texel(sampler, face, level0, x1, y0, z1, texel1, 1); 801 get_texel(sampler, face, level0, x0, y1, z1, texel1, 2); 802 get_texel(sampler, face, level0, x1, y1, z1, texel1, 3); 803 804 /* 3D lerp */ 805 for (c = 0; c < 4; c++) { 806 float ctemp0[4][4], ctemp1[4][4]; 807 ctemp0[c][j] = lerp_2d(xw, yw, 808 texel0[c][0], texel0[c][1], 809 texel0[c][2], texel0[c][3]); 810 ctemp1[c][j] = lerp_2d(xw, yw, 811 texel1[c][0], texel1[c][1], 812 texel1[c][2], texel1[c][3]); 813 rgba[c][j] = LERP(zw, ctemp0[c][j], ctemp1[c][j]); 814 } 815 816 if (level0 != level1) { 817 /* get texels from second mipmap level and blend */ 818 float rgba2[4][4]; 819 x0 /= 2; 820 y0 /= 2; 821 z0 /= 2; 822 x1 /= 2; 823 y1 /= 2; 824 z1 /= 2; 825 get_texel(sampler, face, level1, x0, y0, z0, texel0, 0); 826 get_texel(sampler, face, level1, x1, y0, z0, texel0, 1); 827 get_texel(sampler, face, level1, x0, y1, z0, texel0, 2); 828 get_texel(sampler, face, level1, x1, y1, z0, texel0, 3); 829 get_texel(sampler, face, level1, x0, y0, z1, texel1, 0); 830 get_texel(sampler, face, level1, x1, y0, z1, texel1, 1); 831 get_texel(sampler, face, level1, x0, y1, z1, texel1, 2); 832 get_texel(sampler, face, level1, x1, y1, z1, texel1, 3); 833 834 /* 3D lerp */ 835 for (c = 0; c < 4; c++) { 836 float ctemp0[4][4], ctemp1[4][4]; 837 ctemp0[c][j] = lerp_2d(xw, yw, 838 texel0[c][0], texel0[c][1], 839 texel0[c][2], texel0[c][3]); 840 ctemp1[c][j] = lerp_2d(xw, yw, 841 texel1[c][0], texel1[c][1], 842 texel1[c][2], texel1[c][3]); 843 rgba2[c][j] = LERP(zw, ctemp0[c][j], ctemp1[c][j]); 844 } 845 846 /* blend mipmap levels */ 847 for (c = 0; c < NUM_CHANNELS; c++) { 848 rgba[c][j] = LERP(levelBlend, rgba[c][j], rgba2[c][j]); 849 } 850 } 851 } 852 break; 853 default: 854 assert(0); 855 } 856} 857 858 859static void 860sp_get_samples_cube(struct tgsi_sampler *sampler, 861 const float s[QUAD_SIZE], 862 const float t[QUAD_SIZE], 863 const float p[QUAD_SIZE], 864 float lodbias, 865 float rgba[NUM_CHANNELS][QUAD_SIZE]) 866{ 867 unsigned faces[QUAD_SIZE], j; 868 float ssss[4], tttt[4]; 869 for (j = 0; j < QUAD_SIZE; j++) { 870 faces[j] = choose_cube_face(s[j], t[j], p[j], ssss + j, tttt + j); 871 } 872 sp_get_samples_2d_common(sampler, ssss, tttt, NULL, lodbias, rgba, faces); 873} 874 875 876/** 877 * Called via tgsi_sampler::get_samples() 878 * Use the sampler's state setting to get a filtered RGBA value 879 * from the sampler's texture. 880 * 881 * XXX we can implement many versions of this function, each 882 * tightly coded for a specific combination of sampler state 883 * (nearest + repeat), (bilinear mipmap + clamp), etc. 884 * 885 * The update_samplers() function in st_atom_sampler.c could create 886 * a new tgsi_sampler object for each state combo it finds.... 887 */ 888void 889sp_get_samples(struct tgsi_sampler *sampler, 890 const float s[QUAD_SIZE], 891 const float t[QUAD_SIZE], 892 const float p[QUAD_SIZE], 893 float lodbias, 894 float rgba[NUM_CHANNELS][QUAD_SIZE]) 895{ 896 if (!sampler->texture) 897 return; 898 899 switch (sampler->texture->target) { 900 case PIPE_TEXTURE_1D: 901 sp_get_samples_1d(sampler, s, t, p, lodbias, rgba); 902 break; 903 case PIPE_TEXTURE_2D: 904 sp_get_samples_2d(sampler, s, t, p, lodbias, rgba); 905 break; 906 case PIPE_TEXTURE_3D: 907 sp_get_samples_3d(sampler, s, t, p, lodbias, rgba); 908 break; 909 case PIPE_TEXTURE_CUBE: 910 sp_get_samples_cube(sampler, s, t, p, lodbias, rgba); 911 break; 912 default: 913 assert(0); 914 } 915} 916 917