src/mesa/main/texfetch.c

   1 /*
   2  * Mesa 3-D graphics library
   3  * Version:  7.7
   4  *
   5  * Copyright (C) 1999-2008  Brian Paul   All Rights Reserved.
   6  * Copyright (c) 2009  VMware, Inc.
   7  *
   8  * Permission is hereby granted, free of charge, to any person obtaining a
   9  * copy of this software and associated documentation files (the "Software"),
  10  * to deal in the Software without restriction, including without limitation
  11  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  12  * and/or sell copies of the Software, and to permit persons to whom the
  13  * Software is furnished to do so, subject to the following conditions:
  14  *
  15  * The above copyright notice and this permission notice shall be included
  16  * in all copies or substantial portions 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 MERCHANTABILITY,
  20  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  21  * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
  22  * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  23  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  24  */
  25
  26
  27 /**
  28  * \file texfetch.c
  29  *
  30  * Texel fetch/store functions
  31  *
  32  * \author Gareth Hughes
  33  */
  34
  35
  36 #include "colormac.h"
  37 #include "macros.h"
  38 #include "texcompress.h"
  39 #include "texcompress_fxt1.h"
  40 #include "texcompress_s3tc.h"
  41 #include "texfetch.h"
  42 #include "teximage.h"
  43
  44
  45 /**
  46  * Convert an 8-bit sRGB value from non-linear space to a
  47  * linear RGB value in [0, 1].
  48  * Implemented with a 256-entry lookup table.
  49  */
  50 static INLINE GLfloat
  51 nonlinear_to_linear(GLubyte cs8)
  52 {
  53    static GLfloat table[256];
  54    static GLboolean tableReady = GL_FALSE;
  55    if (!tableReady) {
  56       /* compute lookup table now */
  57       GLuint i;
  58       for (i = 0; i < 256; i++) {
  59          const GLfloat cs = UBYTE_TO_FLOAT(i);
  60          if (cs <= 0.04045) {
  61             table[i] = cs / 12.92f;
  62          }
  63          else {
  64             table[i] = (GLfloat) pow((cs + 0.055) / 1.055, 2.4);
  65          }
  66       }
  67       tableReady = GL_TRUE;
  68    }
  69    return table[cs8];
  70 }
  71
  72
  73
  74 /* Texel fetch routines for all supported formats
  75  */
  76 #define DIM 1
  77 #include "texfetch_tmp.h"
  78
  79 #define DIM 2
  80 #include "texfetch_tmp.h"
  81
  82 #define DIM 3
  83 #include "texfetch_tmp.h"
  84
  85 /**
  86  * Null texel fetch function.
  87  *
  88  * Have to have this so the FetchTexel function pointer is never NULL.
  89  */
  90 static void fetch_null_texelf( const struct gl_texture_image *texImage,
  91                                GLint i, GLint j, GLint k, GLfloat *texel )
  92 {
  93    (void) texImage; (void) i; (void) j; (void) k;
  94    texel[RCOMP] = 0.0;
  95    texel[GCOMP] = 0.0;
  96    texel[BCOMP] = 0.0;
  97    texel[ACOMP] = 0.0;
  98    _mesa_warning(NULL, "fetch_null_texelf() called!");
  99 }
 100
 101 static void store_null_texel(struct gl_texture_image *texImage,
 102                              GLint i, GLint j, GLint k, const void *texel)
 103 {
 104    (void) texImage;
 105    (void) i;
 106    (void) j;
 107    (void) k;
 108    (void) texel;
 109    /* no-op */
 110 }
 111
 112
 113
 114 /**
 115  * Table to map MESA_FORMAT_ to texel fetch/store funcs.
 116  * XXX this is somewhat temporary.
 117  */
 118 static struct {
 119    gl_format Name;
 120    FetchTexelFuncF Fetch1D;
 121    FetchTexelFuncF Fetch2D;
 122    FetchTexelFuncF Fetch3D;
 123    StoreTexelFunc StoreTexel;
 124 }
 125 texfetch_funcs[MESA_FORMAT_COUNT] =
 126 {
 127    {
 128       MESA_FORMAT_NONE,
 129       fetch_null_texelf,
 130       fetch_null_texelf,
 131       fetch_null_texelf,
 132       store_null_texel
 133    },
 134
 135    {
 136       MESA_FORMAT_RGBA8888,
 137       fetch_texel_1d_f_rgba8888,
 138       fetch_texel_2d_f_rgba8888,
 139       fetch_texel_3d_f_rgba8888,
 140       store_texel_rgba8888
 141    },
 142    {
 143       MESA_FORMAT_RGBA8888_REV,
 144       fetch_texel_1d_f_rgba8888_rev,
 145       fetch_texel_2d_f_rgba8888_rev,
 146       fetch_texel_3d_f_rgba8888_rev,
 147       store_texel_rgba8888_rev
 148    },
 149    {
 150       MESA_FORMAT_ARGB8888,
 151       fetch_texel_1d_f_argb8888,
 152       fetch_texel_2d_f_argb8888,
 153       fetch_texel_3d_f_argb8888,
 154       store_texel_argb8888
 155    },
 156    {
 157       MESA_FORMAT_ARGB8888_REV,
 158       fetch_texel_1d_f_argb8888_rev,
 159       fetch_texel_2d_f_argb8888_rev,
 160       fetch_texel_3d_f_argb8888_rev,
 161       store_texel_argb8888_rev
 162    },
 163    {
 164       MESA_FORMAT_XRGB8888,
 165       fetch_texel_1d_f_xrgb8888,
 166       fetch_texel_2d_f_xrgb8888,
 167       fetch_texel_3d_f_xrgb8888,
 168       store_texel_xrgb8888
 169    },
 170    {
 171       MESA_FORMAT_XRGB8888_REV,
 172       fetch_texel_1d_f_xrgb8888_rev,
 173       fetch_texel_2d_f_xrgb8888_rev,
 174       fetch_texel_3d_f_xrgb8888_rev,
 175       store_texel_xrgb8888_rev,
 176    },
 177    {
 178       MESA_FORMAT_RGB888,
 179       fetch_texel_1d_f_rgb888,
 180       fetch_texel_2d_f_rgb888,
 181       fetch_texel_3d_f_rgb888,
 182       store_texel_rgb888
 183    },
 184    {
 185       MESA_FORMAT_BGR888,
 186       fetch_texel_1d_f_bgr888,
 187       fetch_texel_2d_f_bgr888,
 188       fetch_texel_3d_f_bgr888,
 189       store_texel_bgr888
 190    },
 191    {
 192       MESA_FORMAT_RGB565,
 193       fetch_texel_1d_f_rgb565,
 194       fetch_texel_2d_f_rgb565,
 195       fetch_texel_3d_f_rgb565,
 196       store_texel_rgb565
 197    },
 198    {
 199       MESA_FORMAT_RGB565_REV,
 200       fetch_texel_1d_f_rgb565_rev,
 201       fetch_texel_2d_f_rgb565_rev,
 202       fetch_texel_3d_f_rgb565_rev,
 203       store_texel_rgb565_rev
 204    },
 205    {
 206       MESA_FORMAT_ARGB4444,
 207       fetch_texel_1d_f_argb4444,
 208       fetch_texel_2d_f_argb4444,
 209       fetch_texel_3d_f_argb4444,
 210       store_texel_argb4444
 211    },
 212    {
 213       MESA_FORMAT_ARGB4444_REV,
 214       fetch_texel_1d_f_argb4444_rev,
 215       fetch_texel_2d_f_argb4444_rev,
 216       fetch_texel_3d_f_argb4444_rev,
 217       store_texel_argb4444_rev
 218    },
 219    {
 220       MESA_FORMAT_RGBA5551,
 221       fetch_texel_1d_f_rgba5551,
 222       fetch_texel_2d_f_rgba5551,
 223       fetch_texel_3d_f_rgba5551,
 224       store_texel_rgba5551
 225    },
 226    {
 227       MESA_FORMAT_ARGB1555,
 228       fetch_texel_1d_f_argb1555,
 229       fetch_texel_2d_f_argb1555,
 230       fetch_texel_3d_f_argb1555,
 231       store_texel_argb1555
 232    },
 233    {
 234       MESA_FORMAT_ARGB1555_REV,
 235       fetch_texel_1d_f_argb1555_rev,
 236       fetch_texel_2d_f_argb1555_rev,
 237       fetch_texel_3d_f_argb1555_rev,
 238       store_texel_argb1555_rev
 239    },
 240    {
 241       MESA_FORMAT_AL44,
 242       fetch_texel_1d_f_al44,
 243       fetch_texel_2d_f_al44,
 244       fetch_texel_3d_f_al44,
 245       store_texel_al44
 246    },
 247    {
 248       MESA_FORMAT_AL88,
 249       fetch_texel_1d_f_al88,
 250       fetch_texel_2d_f_al88,
 251       fetch_texel_3d_f_al88,
 252       store_texel_al88
 253    },
 254    {
 255       MESA_FORMAT_AL88_REV,
 256       fetch_texel_1d_f_al88_rev,
 257       fetch_texel_2d_f_al88_rev,
 258       fetch_texel_3d_f_al88_rev,
 259       store_texel_al88_rev
 260    },
 261    {
 262       MESA_FORMAT_AL1616,
 263       fetch_texel_1d_f_al1616,
 264       fetch_texel_2d_f_al1616,
 265       fetch_texel_3d_f_al1616,
 266       store_texel_al1616
 267    },
 268    {
 269       MESA_FORMAT_AL1616_REV,
 270       fetch_texel_1d_f_al1616_rev,
 271       fetch_texel_2d_f_al1616_rev,
 272       fetch_texel_3d_f_al1616_rev,
 273       store_texel_al1616_rev
 274    },
 275    {
 276       MESA_FORMAT_RGB332,
 277       fetch_texel_1d_f_rgb332,
 278       fetch_texel_2d_f_rgb332,
 279       fetch_texel_3d_f_rgb332,
 280       store_texel_rgb332
 281    },
 282    {
 283       MESA_FORMAT_A8,
 284       fetch_texel_1d_f_a8,
 285       fetch_texel_2d_f_a8,
 286       fetch_texel_3d_f_a8,
 287       store_texel_a8
 288    },
 289    {
 290       MESA_FORMAT_A16,
 291       fetch_texel_1d_f_a16,
 292       fetch_texel_2d_f_a16,
 293       fetch_texel_3d_f_a16,
 294       store_texel_a16
 295    },
 296    {
 297       MESA_FORMAT_L8,
 298       fetch_texel_1d_f_l8,
 299       fetch_texel_2d_f_l8,
 300       fetch_texel_3d_f_l8,
 301       store_texel_l8
 302    },
 303    {
 304       MESA_FORMAT_L16,
 305       fetch_texel_1d_f_l16,
 306       fetch_texel_2d_f_l16,
 307       fetch_texel_3d_f_l16,
 308       store_texel_l16
 309    },
 310    {
 311       MESA_FORMAT_I8,
 312       fetch_texel_1d_f_i8,
 313       fetch_texel_2d_f_i8,
 314       fetch_texel_3d_f_i8,
 315       store_texel_i8
 316    },
 317    {
 318       MESA_FORMAT_I16,
 319       fetch_texel_1d_f_i16,
 320       fetch_texel_2d_f_i16,
 321       fetch_texel_3d_f_i16,
 322       store_texel_i16
 323    },
 324    {
 325       MESA_FORMAT_CI8,
 326       fetch_texel_1d_f_ci8,
 327       fetch_texel_2d_f_ci8,
 328       fetch_texel_3d_f_ci8,
 329       store_texel_ci8
 330    },
 331    {
 332       MESA_FORMAT_YCBCR,
 333       fetch_texel_1d_f_ycbcr,
 334       fetch_texel_2d_f_ycbcr,
 335       fetch_texel_3d_f_ycbcr,
 336       store_texel_ycbcr
 337    },
 338    {
 339       MESA_FORMAT_YCBCR_REV,
 340       fetch_texel_1d_f_ycbcr_rev,
 341       fetch_texel_2d_f_ycbcr_rev,
 342       fetch_texel_3d_f_ycbcr_rev,
 343       store_texel_ycbcr_rev
 344    },
 345    {
 346       MESA_FORMAT_R8,
 347       fetch_texel_1d_f_r8,
 348       fetch_texel_2d_f_r8,
 349       fetch_texel_3d_f_r8,
 350       store_texel_r8,
 351    },
 352    {
 353       MESA_FORMAT_RG88,
 354       fetch_texel_1d_f_rg88,
 355       fetch_texel_2d_f_rg88,
 356       fetch_texel_3d_f_rg88,
 357       store_texel_rg88,
 358    },
 359    {
 360       MESA_FORMAT_RG88_REV,
 361       fetch_texel_1d_f_rg88_rev,
 362       fetch_texel_2d_f_rg88_rev,
 363       fetch_texel_3d_f_rg88_rev,
 364       store_texel_rg88_rev,
 365    },
 366    {
 367       MESA_FORMAT_R16,
 368       fetch_texel_1d_f_r16,
 369       fetch_texel_2d_f_r16,
 370       fetch_texel_3d_f_r16,
 371       store_texel_r16,
 372    },
 373    {
 374       MESA_FORMAT_RG1616,
 375       fetch_texel_1d_f_rg1616,
 376       fetch_texel_2d_f_rg1616,
 377       fetch_texel_3d_f_rg1616,
 378       store_texel_rg1616,
 379    },
 380    {
 381       MESA_FORMAT_RG1616_REV,
 382       fetch_texel_1d_f_rg1616_rev,
 383       fetch_texel_2d_f_rg1616_rev,
 384       fetch_texel_3d_f_rg1616_rev,
 385       store_texel_rg1616_rev,
 386    },
 387    {
 388       MESA_FORMAT_ARGB2101010,
 389       fetch_texel_1d_f_argb2101010,
 390       fetch_texel_2d_f_argb2101010,
 391       fetch_texel_3d_f_argb2101010,
 392       store_texel_argb2101010
 393    },
 394    {
 395       MESA_FORMAT_Z24_S8,
 396       fetch_texel_1d_f_z24_s8,
 397       fetch_texel_2d_f_z24_s8,
 398       fetch_texel_3d_f_z24_s8,
 399       store_texel_z24_s8
 400    },
 401    {
 402       MESA_FORMAT_S8_Z24,
 403       fetch_texel_1d_f_s8_z24,
 404       fetch_texel_2d_f_s8_z24,
 405       fetch_texel_3d_f_s8_z24,
 406       store_texel_s8_z24
 407    },
 408    {
 409       MESA_FORMAT_Z16,
 410       fetch_texel_1d_f_z16,
 411       fetch_texel_2d_f_z16,
 412       fetch_texel_3d_f_z16,
 413       store_texel_z16
 414    },
 415    {
 416       MESA_FORMAT_X8_Z24,
 417       fetch_texel_1d_f_s8_z24,
 418       fetch_texel_2d_f_s8_z24,
 419       fetch_texel_3d_f_s8_z24,
 420       store_texel_s8_z24
 421    },
 422    {
 423       MESA_FORMAT_Z24_X8,
 424       fetch_texel_1d_f_z24_s8,
 425       fetch_texel_2d_f_z24_s8,
 426       fetch_texel_3d_f_z24_s8,
 427       store_texel_z24_s8
 428    },
 429    {
 430       MESA_FORMAT_Z32,
 431       fetch_texel_1d_f_z32,
 432       fetch_texel_2d_f_z32,
 433       fetch_texel_3d_f_z32,
 434       store_texel_z32
 435    },
 436    {
 437       MESA_FORMAT_S8,
 438       NULL,
 439       NULL,
 440       NULL,
 441       NULL
 442    },
 443    {
 444       MESA_FORMAT_SRGB8,
 445       fetch_texel_1d_srgb8,
 446       fetch_texel_2d_srgb8,
 447       fetch_texel_3d_srgb8,
 448       store_texel_srgb8
 449    },
 450    {
 451       MESA_FORMAT_SRGBA8,
 452       fetch_texel_1d_srgba8,
 453       fetch_texel_2d_srgba8,
 454       fetch_texel_3d_srgba8,
 455       store_texel_srgba8
 456    },
 457    {
 458       MESA_FORMAT_SARGB8,
 459       fetch_texel_1d_sargb8,
 460       fetch_texel_2d_sargb8,
 461       fetch_texel_3d_sargb8,
 462       store_texel_sargb8
 463    },
 464    {
 465       MESA_FORMAT_SL8,
 466       fetch_texel_1d_sl8,
 467       fetch_texel_2d_sl8,
 468       fetch_texel_3d_sl8,
 469       store_texel_sl8
 470    },
 471    {
 472       MESA_FORMAT_SLA8,
 473       fetch_texel_1d_sla8,
 474       fetch_texel_2d_sla8,
 475       fetch_texel_3d_sla8,
 476       store_texel_sla8
 477    },
 478    {
 479       MESA_FORMAT_SRGB_DXT1,
 480       NULL,
 481       _mesa_fetch_texel_2d_f_srgb_dxt1,
 482       NULL,
 483       NULL
 484    },
 485    {
 486       MESA_FORMAT_SRGBA_DXT1,
 487       NULL,
 488       _mesa_fetch_texel_2d_f_srgba_dxt1,
 489       NULL,
 490       NULL
 491    },
 492    {
 493       MESA_FORMAT_SRGBA_DXT3,
 494       NULL,
 495       _mesa_fetch_texel_2d_f_srgba_dxt3,
 496       NULL,
 497       NULL
 498    },
 499    {
 500       MESA_FORMAT_SRGBA_DXT5,
 501       NULL,
 502       _mesa_fetch_texel_2d_f_srgba_dxt5,
 503       NULL,
 504       NULL
 505    },
 506
 507    {
 508       MESA_FORMAT_RGB_FXT1,
 509       NULL,
 510       _mesa_fetch_texel_2d_f_rgb_fxt1,
 511       NULL,
 512       NULL
 513    },
 514    {
 515       MESA_FORMAT_RGBA_FXT1,
 516       NULL,
 517       _mesa_fetch_texel_2d_f_rgba_fxt1,
 518       NULL,
 519       NULL
 520    },
 521    {
 522       MESA_FORMAT_RGB_DXT1,
 523       NULL,
 524       _mesa_fetch_texel_2d_f_rgb_dxt1,
 525       NULL,
 526       NULL
 527    },
 528    {
 529       MESA_FORMAT_RGBA_DXT1,
 530       NULL,
 531       _mesa_fetch_texel_2d_f_rgba_dxt1,
 532       NULL,
 533       NULL
 534    },
 535    {
 536       MESA_FORMAT_RGBA_DXT3,
 537       NULL,
 538       _mesa_fetch_texel_2d_f_rgba_dxt3,
 539       NULL,
 540       NULL
 541    },
 542    {
 543       MESA_FORMAT_RGBA_DXT5,
 544       NULL,
 545       _mesa_fetch_texel_2d_f_rgba_dxt5,
 546       NULL,
 547       NULL
 548    },
 549    {
 550       MESA_FORMAT_RGBA_FLOAT32,
 551       fetch_texel_1d_f_rgba_f32,
 552       fetch_texel_2d_f_rgba_f32,
 553       fetch_texel_3d_f_rgba_f32,
 554       store_texel_rgba_f32
 555    },
 556    {
 557       MESA_FORMAT_RGBA_FLOAT16,
 558       fetch_texel_1d_f_rgba_f16,
 559       fetch_texel_2d_f_rgba_f16,
 560       fetch_texel_3d_f_rgba_f16,
 561       store_texel_rgba_f16
 562    },
 563    {
 564       MESA_FORMAT_RGB_FLOAT32,
 565       fetch_texel_1d_f_rgb_f32,
 566       fetch_texel_2d_f_rgb_f32,
 567       fetch_texel_3d_f_rgb_f32,
 568       store_texel_rgb_f32
 569    },
 570    {
 571       MESA_FORMAT_RGB_FLOAT16,
 572       fetch_texel_1d_f_rgb_f16,
 573       fetch_texel_2d_f_rgb_f16,
 574       fetch_texel_3d_f_rgb_f16,
 575       store_texel_rgb_f16
 576    },
 577    {
 578       MESA_FORMAT_ALPHA_FLOAT32,
 579       fetch_texel_1d_f_alpha_f32,
 580       fetch_texel_2d_f_alpha_f32,
 581       fetch_texel_3d_f_alpha_f32,
 582       store_texel_alpha_f32
 583    },
 584    {
 585       MESA_FORMAT_ALPHA_FLOAT16,
 586       fetch_texel_1d_f_alpha_f16,
 587       fetch_texel_2d_f_alpha_f16,
 588       fetch_texel_3d_f_alpha_f16,
 589       store_texel_alpha_f16
 590    },
 591    {
 592       MESA_FORMAT_LUMINANCE_FLOAT32,
 593       fetch_texel_1d_f_luminance_f32,
 594       fetch_texel_2d_f_luminance_f32,
 595       fetch_texel_3d_f_luminance_f32,
 596       store_texel_luminance_f32
 597    },
 598    {
 599       MESA_FORMAT_LUMINANCE_FLOAT16,
 600       fetch_texel_1d_f_luminance_f16,
 601       fetch_texel_2d_f_luminance_f16,
 602       fetch_texel_3d_f_luminance_f16,
 603       store_texel_luminance_f16
 604    },
 605    {
 606       MESA_FORMAT_LUMINANCE_ALPHA_FLOAT32,
 607       fetch_texel_1d_f_luminance_alpha_f32,
 608       fetch_texel_2d_f_luminance_alpha_f32,
 609       fetch_texel_3d_f_luminance_alpha_f32,
 610       store_texel_luminance_alpha_f32
 611    },
 612    {
 613       MESA_FORMAT_LUMINANCE_ALPHA_FLOAT16,
 614       fetch_texel_1d_f_luminance_alpha_f16,
 615       fetch_texel_2d_f_luminance_alpha_f16,
 616       fetch_texel_3d_f_luminance_alpha_f16,
 617       store_texel_luminance_alpha_f16
 618    },
 619    {
 620       MESA_FORMAT_INTENSITY_FLOAT32,
 621       fetch_texel_1d_f_intensity_f32,
 622       fetch_texel_2d_f_intensity_f32,
 623       fetch_texel_3d_f_intensity_f32,
 624       store_texel_intensity_f32
 625    },
 626    {
 627       MESA_FORMAT_INTENSITY_FLOAT16,
 628       fetch_texel_1d_f_intensity_f16,
 629       fetch_texel_2d_f_intensity_f16,
 630       fetch_texel_3d_f_intensity_f16,
 631       store_texel_intensity_f16
 632    },
 633
 634    /* non-normalized, signed int */
 635    {
 636       MESA_FORMAT_RGBA_INT8,
 637       fetch_texel_1d_rgba_int8,
 638       fetch_texel_2d_rgba_int8,
 639       fetch_texel_3d_rgba_int8,
 640       store_texel_rgba_int8
 641    },
 642    {
 643       MESA_FORMAT_RGBA_INT16,
 644       fetch_texel_1d_rgba_int16,
 645       fetch_texel_2d_rgba_int16,
 646       fetch_texel_3d_rgba_int16,
 647       store_texel_rgba_int16
 648    },
 649    {
 650       MESA_FORMAT_RGBA_INT32,
 651       fetch_texel_1d_rgba_int32,
 652       fetch_texel_2d_rgba_int32,
 653       fetch_texel_3d_rgba_int32,
 654       store_texel_rgba_int32
 655    },
 656
 657    /* non-normalized, unsigned int */
 658    {
 659       MESA_FORMAT_RGBA_UINT8,
 660       fetch_texel_1d_rgba_uint8,
 661       fetch_texel_2d_rgba_uint8,
 662       fetch_texel_3d_rgba_uint8,
 663       store_texel_rgba_uint8
 664    },
 665    {
 666       MESA_FORMAT_RGBA_UINT16,
 667       fetch_texel_1d_rgba_uint16,
 668       fetch_texel_2d_rgba_uint16,
 669       fetch_texel_3d_rgba_uint16,
 670       store_texel_rgba_uint16
 671    },
 672    {
 673       MESA_FORMAT_RGBA_UINT32,
 674       fetch_texel_1d_rgba_uint32,
 675       fetch_texel_2d_rgba_uint32,
 676       fetch_texel_3d_rgba_uint32,
 677       store_texel_rgba_uint32
 678    },
 679
 680    /* dudv */
 681    {
 682       MESA_FORMAT_DUDV8,
 683       fetch_texel_1d_dudv8,
 684       fetch_texel_2d_dudv8,
 685       fetch_texel_3d_dudv8,
 686       NULL
 687    },
 688
 689    /* signed, normalized */
 690    {
 691       MESA_FORMAT_SIGNED_R8,
 692       fetch_texel_1d_signed_r8,
 693       fetch_texel_2d_signed_r8,
 694       fetch_texel_3d_signed_r8,
 695       store_texel_signed_r8
 696    },
 697    {
 698       MESA_FORMAT_SIGNED_RG88,
 699       fetch_texel_1d_signed_rg88,
 700       fetch_texel_2d_signed_rg88,
 701       fetch_texel_3d_signed_rg88,
 702       store_texel_signed_rg88
 703    },
 704    {
 705       MESA_FORMAT_SIGNED_RGBX8888,
 706       fetch_texel_1d_signed_rgbx8888,
 707       fetch_texel_2d_signed_rgbx8888,
 708       fetch_texel_3d_signed_rgbx8888,
 709       store_texel_signed_rgbx8888
 710    },
 711    {
 712       MESA_FORMAT_SIGNED_RGBA8888,
 713       fetch_texel_1d_signed_rgba8888,
 714       fetch_texel_2d_signed_rgba8888,
 715       fetch_texel_3d_signed_rgba8888,
 716       store_texel_signed_rgba8888
 717    },
 718    {
 719       MESA_FORMAT_SIGNED_RGBA8888_REV,
 720       fetch_texel_1d_signed_rgba8888_rev,
 721       fetch_texel_2d_signed_rgba8888_rev,
 722       fetch_texel_3d_signed_rgba8888_rev,
 723       store_texel_signed_rgba8888_rev
 724    },
 725    {
 726       MESA_FORMAT_SIGNED_R_16,
 727       fetch_texel_1d_signed_r_16,
 728       fetch_texel_2d_signed_r_16,
 729       fetch_texel_3d_signed_r_16,
 730       store_texel_signed_r_16
 731    },
 732    {
 733       MESA_FORMAT_SIGNED_RG_16,
 734       fetch_texel_1d_signed_rg_16,
 735       fetch_texel_2d_signed_rg_16,
 736       fetch_texel_3d_signed_rg_16,
 737       store_texel_signed_rg_16
 738    },
 739    {
 740       MESA_FORMAT_SIGNED_RGB_16,
 741       fetch_texel_1d_signed_rgb_16,
 742       fetch_texel_2d_signed_rgb_16,
 743       fetch_texel_3d_signed_rgb_16,
 744       store_texel_signed_rgb_16
 745    },
 746    {
 747       MESA_FORMAT_SIGNED_RGBA_16,
 748       fetch_texel_1d_signed_rgba_16,
 749       fetch_texel_2d_signed_rgba_16,
 750       fetch_texel_3d_signed_rgba_16,
 751       store_texel_signed_rgba_16
 752    },
 753    {
 754       MESA_FORMAT_RGBA_16,
 755       fetch_texel_1d_rgba_16,
 756       fetch_texel_2d_rgba_16,
 757       fetch_texel_3d_rgba_16,
 758       store_texel_rgba_16
 759    }
 760 };
 761
 762
 763 FetchTexelFuncF
 764 _mesa_get_texel_fetch_func(gl_format format, GLuint dims)
 765 {
 766 #ifdef DEBUG
 767    /* check that the table entries are sorted by format name */
 768    gl_format fmt;
 769    for (fmt = 0; fmt < MESA_FORMAT_COUNT; fmt++) {
 770       assert(texfetch_funcs[fmt].Name == fmt);
 771    }
 772 #endif
 773
 774    assert(Elements(texfetch_funcs) == MESA_FORMAT_COUNT);
 775    assert(format < MESA_FORMAT_COUNT);
 776
 777    switch (dims) {
 778    case 1:
 779       return texfetch_funcs[format].Fetch1D;
 780    case 2:
 781       return texfetch_funcs[format].Fetch2D;
 782    case 3:
 783       return texfetch_funcs[format].Fetch3D;
 784    default:
 785       assert(0 && "bad dims in _mesa_get_texel_fetch_func");
 786       return NULL;
 787    }
 788 }
 789
 790
 791 StoreTexelFunc
 792 _mesa_get_texel_store_func(gl_format format)
 793 {
 794    assert(format < MESA_FORMAT_COUNT);
 795    return texfetch_funcs[format].StoreTexel;
 796 }
 797
 798
 799 /**
 800  * Adaptor for fetching a GLchan texel from a float-valued texture.
 801  */
 802 static void
 803 fetch_texel_float_to_chan(const struct gl_texture_image *texImage,
 804                           GLint i, GLint j, GLint k, GLchan *texelOut)
 805 {
 806    GLfloat temp[4];
 807    GLenum baseFormat = _mesa_get_format_base_format(texImage->TexFormat);
 808
 809    ASSERT(texImage->FetchTexelf);
 810    texImage->FetchTexelf(texImage, i, j, k, temp);
 811    if (baseFormat == GL_DEPTH_COMPONENT ||
 812        baseFormat == GL_DEPTH_STENCIL_EXT) {
 813       /* just one channel */
 814       UNCLAMPED_FLOAT_TO_CHAN(texelOut[0], temp[0]);
 815    }
 816    else {
 817       /* four channels */
 818       UNCLAMPED_FLOAT_TO_CHAN(texelOut[0], temp[0]);
 819       UNCLAMPED_FLOAT_TO_CHAN(texelOut[1], temp[1]);
 820       UNCLAMPED_FLOAT_TO_CHAN(texelOut[2], temp[2]);
 821       UNCLAMPED_FLOAT_TO_CHAN(texelOut[3], temp[3]);
 822    }
 823 }
 824
 825
 826 #if 0
 827 /**
 828  * Adaptor for fetching a float texel from a GLchan-valued texture.
 829  */
 830 static void
 831 fetch_texel_chan_to_float(const struct gl_texture_image *texImage,
 832                           GLint i, GLint j, GLint k, GLfloat *texelOut)
 833 {
 834    GLchan temp[4];
 835    GLenum baseFormat = _mesa_get_format_base_format(texImage->TexFormat);
 836
 837    ASSERT(texImage->FetchTexelc);
 838    texImage->FetchTexelc(texImage, i, j, k, temp);
 839    if (baseFormat == GL_DEPTH_COMPONENT ||
 840        baseFormat == GL_DEPTH_STENCIL_EXT) {
 841       /* just one channel */
 842       texelOut[0] = CHAN_TO_FLOAT(temp[0]);
 843    }
 844    else {
 845       /* four channels */
 846       texelOut[0] = CHAN_TO_FLOAT(temp[0]);
 847       texelOut[1] = CHAN_TO_FLOAT(temp[1]);
 848       texelOut[2] = CHAN_TO_FLOAT(temp[2]);
 849       texelOut[3] = CHAN_TO_FLOAT(temp[3]);
 850    }
 851 }
 852 #endif
 853
 854
 855 /**
 856  * Initialize the texture image's FetchTexelc and FetchTexelf methods.
 857  */
 858 void
 859 _mesa_set_fetch_functions(struct gl_texture_image *texImage, GLuint dims)
 860 {
 861    gl_format format = texImage->TexFormat;
 862
 863    ASSERT(dims == 1 || dims == 2 || dims == 3);
 864
 865    if (texImage->TexObject->sRGBDecode == GL_SKIP_DECODE_EXT &&
 866        _mesa_get_format_color_encoding(format) == GL_SRGB) {
 867       format = _mesa_get_srgb_format_linear(format);
 868    }
 869
 870    texImage->FetchTexelf = _mesa_get_texel_fetch_func(format, dims);
 871
 872    texImage->FetchTexelc = fetch_texel_float_to_chan;
 873
 874    ASSERT(texImage->FetchTexelc);
 875    ASSERT(texImage->FetchTexelf);
 876 }
 877
 878 void
 879 _mesa_update_fetch_functions(struct gl_texture_object *texObj)
 880 {
 881    GLuint face, i;
 882    GLuint dims;
 883
 884    dims = _mesa_get_texture_dimensions(texObj->Target);
 885
 886    for (face = 0; face < 6; face++) {
 887       for (i = 0; i < MAX_TEXTURE_LEVELS; i++) {
 888          if (texObj->Image[face][i]) {
 889             _mesa_set_fetch_functions(texObj->Image[face][i], dims);
 890          }
 891       }
 892    }
 893 }