src/mesa/state_tracker/st_format.c

   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 /**
  30  * Texture Image-related functions.
  31  * \author Brian Paul
  32  */
  33
  34 #include "main/imports.h"
  35 #include "main/context.h"
  36 #include "main/texstore.h"
  37 #include "main/texformat.h"
  38 #include "main/enums.h"
  39 #include "main/macros.h"
  40
  41 #include "pipe/p_context.h"
  42 #include "pipe/p_defines.h"
  43 #include "st_context.h"
  44 #include "st_format.h"
  45
  46 static GLuint
  47 format_bits(
  48    pipe_format_rgbazs_t  info,
  49    GLuint comp )
  50 {
  51    GLuint   size;
  52
  53    if (pf_swizzle_x(info) == comp) {
  54       size = pf_size_x(info);
  55    }
  56    else if (pf_swizzle_y(info) == comp) {
  57       size = pf_size_y(info);
  58    }
  59    else if (pf_swizzle_z(info) == comp) {
  60       size = pf_size_z(info);
  61    }
  62    else if (pf_swizzle_w(info) == comp) {
  63       size = pf_size_w(info);
  64    }
  65    else {
  66       size = 0;
  67    }
  68    return size << (pf_exp8(info) * 3);
  69 }
  70
  71 static GLuint
  72 format_max_bits(
  73    pipe_format_rgbazs_t  info )
  74 {
  75    GLuint   size = format_bits( info, PIPE_FORMAT_COMP_R );
  76
  77    size = MAX2( size, format_bits( info, PIPE_FORMAT_COMP_G ) );
  78    size = MAX2( size, format_bits( info, PIPE_FORMAT_COMP_B ) );
  79    size = MAX2( size, format_bits( info, PIPE_FORMAT_COMP_A ) );
  80    size = MAX2( size, format_bits( info, PIPE_FORMAT_COMP_Z ) );
  81    size = MAX2( size, format_bits( info, PIPE_FORMAT_COMP_S ) );
  82    return size;
  83 }
  84
  85 static GLuint
  86 format_size(
  87    pipe_format_rgbazs_t  info )
  88 {
  89    return
  90       format_bits( info, PIPE_FORMAT_COMP_R ) +
  91       format_bits( info, PIPE_FORMAT_COMP_G ) +
  92       format_bits( info, PIPE_FORMAT_COMP_B ) +
  93       format_bits( info, PIPE_FORMAT_COMP_A ) +
  94       format_bits( info, PIPE_FORMAT_COMP_Z ) +
  95       format_bits( info, PIPE_FORMAT_COMP_S );
  96 }
  97
  98 /*
  99  * XXX temporary here
 100  */
 101 GLboolean
 102 st_get_format_info(
 103    GLuint format,
 104    struct pipe_format_info *pinfo )
 105 {
 106    if (pf_layout(format) == PIPE_FORMAT_LAYOUT_RGBAZS) {
 107       pipe_format_rgbazs_t info;
 108
 109       info = format;
 110
 111 #if 0
 112       printf(
 113          "PIPE_FORMAT: X(%u), Y(%u), Z(%u), W(%u)\n",
 114          info.sizeX,
 115          info.sizeY,
 116          info.sizeZ,
 117          info.sizeW );
 118 #endif
 119
 120       /* Data type */
 121       if (format == PIPE_FORMAT_U_A1_R5_G5_B5 || format == PIPE_FORMAT_U_R5_G6_B5) {
 122          pinfo->datatype = GL_UNSIGNED_SHORT;
 123       }
 124       else {
 125          GLuint size;
 126
 127          size = format_max_bits( info );
 128          if (size == 8) {
 129             if (pf_type(info) == PIPE_FORMAT_TYPE_UNORM)
 130                pinfo->datatype = GL_UNSIGNED_BYTE;
 131             else
 132                pinfo->datatype = GL_BYTE;
 133          }
 134          else if (size == 16) {
 135             if (pf_type(info) == PIPE_FORMAT_TYPE_UNORM)
 136                pinfo->datatype = GL_UNSIGNED_SHORT;
 137             else
 138                pinfo->datatype = GL_SHORT;
 139          }
 140          else {
 141             assert( size <= 32 );
 142             if (pf_type(info) == PIPE_FORMAT_TYPE_UNORM)
 143                pinfo->datatype = GL_UNSIGNED_INT;
 144             else
 145                pinfo->datatype = GL_INT;
 146          }
 147       }
 148
 149       /* Component bits */
 150       pinfo->red_bits = format_bits( info, PIPE_FORMAT_COMP_R );
 151       pinfo->green_bits = format_bits( info, PIPE_FORMAT_COMP_G );
 152       pinfo->blue_bits = format_bits( info, PIPE_FORMAT_COMP_B );
 153       pinfo->alpha_bits = format_bits( info, PIPE_FORMAT_COMP_A );
 154       pinfo->depth_bits = format_bits( info, PIPE_FORMAT_COMP_Z );
 155       pinfo->stencil_bits = format_bits( info, PIPE_FORMAT_COMP_S );
 156
 157       /* Format size */
 158       pinfo->size = format_size( info ) / 8;
 159
 160       /* Luminance & Intensity bits */
 161       if( pf_swizzle_x(info) == PIPE_FORMAT_COMP_R &&
 162           pf_swizzle_y(info) == PIPE_FORMAT_COMP_R &&
 163           pf_swizzle_z(info) == PIPE_FORMAT_COMP_R ) {
 164          if( pf_swizzle_w(info) == PIPE_FORMAT_COMP_R ) {
 165             pinfo->luminance_bits = 0;
 166             pinfo->intensity_bits = pinfo->red_bits;
 167          }
 168          else {
 169             pinfo->luminance_bits = pinfo->red_bits;
 170             pinfo->intensity_bits = 0;
 171          }
 172          pinfo->red_bits = 0;
 173       }
 174
 175       /* Base format */
 176       if (pinfo->depth_bits) {
 177          if (pinfo->stencil_bits) {
 178             pinfo->base_format = GL_DEPTH_STENCIL_EXT;
 179          }
 180          else {
 181             pinfo->base_format = GL_DEPTH_COMPONENT;
 182          }
 183       }
 184       else if (pinfo->stencil_bits) {
 185          pinfo->base_format = GL_STENCIL_INDEX;
 186       }
 187       else {
 188          pinfo->base_format = GL_RGBA;
 189       }
 190    }
 191    else {
 192       pipe_format_ycbcr_t info;
 193
 194       assert( pf_layout(format) == PIPE_FORMAT_LAYOUT_YCBCR );
 195
 196       info = format;
 197
 198       /* TODO */
 199       assert( 0 );
 200    }
 201
 202 #if 0
 203    printf(
 204       "ST_FORMAT: R(%u), G(%u), B(%u), A(%u), Z(%u), S(%u)\n",
 205       pinfo->red_bits,
 206       pinfo->green_bits,
 207       pinfo->blue_bits,
 208       pinfo->alpha_bits,
 209       pinfo->depth_bits,
 210       pinfo->stencil_bits );
 211 #endif
 212
 213    pinfo->format = format;
 214
 215    return GL_TRUE;
 216 }
 217
 218
 219 /**
 220  * Return bytes per pixel for the given format.
 221  */
 222 GLuint
 223 st_sizeof_format(GLuint pipeFormat)
 224 {
 225    struct pipe_format_info info;
 226    if (!st_get_format_info( pipeFormat, &info )) {
 227       assert( 0 );
 228       return 0;
 229    }
 230    return info.size;
 231 }
 232
 233
 234 /**
 235  * Return bytes per pixel for the given format.
 236  */
 237 GLenum
 238 st_format_datatype(GLuint pipeFormat)
 239 {
 240    struct pipe_format_info info;
 241    if (!st_get_format_info( pipeFormat, &info )) {
 242       assert( 0 );
 243       return 0;
 244    }
 245    return info.datatype;
 246 }
 247
 248
 249 GLuint
 250 st_mesa_format_to_pipe_format(GLuint mesaFormat)
 251 {
 252    switch (mesaFormat) {
 253       /* fix this */
 254    case MESA_FORMAT_ARGB8888_REV:
 255    case MESA_FORMAT_ARGB8888:
 256       return PIPE_FORMAT_U_A8_R8_G8_B8;
 257    case MESA_FORMAT_AL88:
 258       return PIPE_FORMAT_U_A8_L8;
 259    case MESA_FORMAT_A8:
 260       return PIPE_FORMAT_U_A8;
 261    case MESA_FORMAT_L8:
 262       return PIPE_FORMAT_U_L8;
 263    case MESA_FORMAT_I8:
 264       return PIPE_FORMAT_U_I8;
 265    case MESA_FORMAT_Z16:
 266       return PIPE_FORMAT_U_Z16;
 267    default:
 268       assert(0);
 269       return 0;
 270    }
 271 }
 272
 273 /**
 274  * Search list of formats for first RGBA format.
 275  */
 276 static GLuint
 277 default_rgba_format(
 278    struct pipe_context *pipe )
 279 {
 280    if (pipe->is_format_supported( pipe, PIPE_FORMAT_U_R8_G8_B8_A8 )) {
 281       return PIPE_FORMAT_U_R8_G8_B8_A8;
 282    }
 283    if (pipe->is_format_supported( pipe, PIPE_FORMAT_U_A8_R8_G8_B8 )) {
 284       return PIPE_FORMAT_U_A8_R8_G8_B8;
 285    }
 286    if (pipe->is_format_supported( pipe, PIPE_FORMAT_U_R5_G6_B5 )) {
 287       return PIPE_FORMAT_U_R5_G6_B5;
 288    }
 289    return PIPE_FORMAT_NONE;
 290 }
 291
 292
 293 /**
 294  * Search list of formats for first RGBA format with >8 bits/channel.
 295  */
 296 static GLuint
 297 default_deep_rgba_format(
 298    struct pipe_context *pipe )
 299 {
 300    if (pipe->is_format_supported( pipe, PIPE_FORMAT_S_R16_G16_B16_A16 )) {
 301       return PIPE_FORMAT_S_R16_G16_B16_A16;
 302    }
 303    return PIPE_FORMAT_NONE;
 304 }
 305
 306
 307 /**
 308  * Search list of formats for first depth/Z format.
 309  */
 310 static GLuint
 311 default_depth_format(
 312    struct pipe_context *pipe )
 313 {
 314    if (pipe->is_format_supported( pipe, PIPE_FORMAT_U_Z16 )) {
 315       return PIPE_FORMAT_U_Z16;
 316    }
 317    if (pipe->is_format_supported( pipe, PIPE_FORMAT_U_Z32 )) {
 318       return PIPE_FORMAT_U_Z32;
 319    }
 320    if (pipe->is_format_supported( pipe, PIPE_FORMAT_S8_Z24 )) {
 321       return PIPE_FORMAT_S8_Z24;
 322    }
 323    return PIPE_FORMAT_NONE;
 324 }
 325
 326 /**
 327  * Choose the PIPE_FORMAT_ to use for storing a texture image based
 328  * on the user's internalFormat, format and type parameters.
 329  * We query the pipe device for a list of formats which it supports
 330  * and choose from them.
 331  * If we find a device that needs a more intricate selection mechanism,
 332  * this function _could_ get pushed down into the pipe device.
 333  *
 334  * Note: also used for glRenderbufferStorageEXT()
 335  *
 336  * Note: format and type may be GL_NONE (see renderbuffers)
 337  *
 338  * \return PIPE_FORMAT_NONE if error/problem.
 339  */
 340 GLuint
 341 st_choose_pipe_format(struct pipe_context *pipe, GLint internalFormat,
 342                       GLenum format, GLenum type)
 343 {
 344    switch (internalFormat) {
 345    case 4:
 346    case GL_RGBA:
 347    case GL_COMPRESSED_RGBA:
 348       if (format == GL_BGRA) {
 349          if (type == GL_UNSIGNED_BYTE || type == GL_UNSIGNED_INT_8_8_8_8_REV) {
 350             if (pipe->is_format_supported( pipe, PIPE_FORMAT_U_A8_R8_G8_B8 ))
 351                return PIPE_FORMAT_U_A8_R8_G8_B8;
 352          }
 353          else if (type == GL_UNSIGNED_SHORT_4_4_4_4_REV) {
 354             if (pipe->is_format_supported( pipe, PIPE_FORMAT_U_A4_R4_G4_B4 ))
 355                return PIPE_FORMAT_U_A4_R4_G4_B4;
 356          }
 357          else if (type == GL_UNSIGNED_SHORT_1_5_5_5_REV) {
 358             if (pipe->is_format_supported( pipe, PIPE_FORMAT_U_A1_R5_G5_B5 ))
 359                return PIPE_FORMAT_U_A1_R5_G5_B5;
 360          }
 361       }
 362       return default_rgba_format( pipe );
 363
 364    case 3:
 365    case GL_RGB:
 366    case GL_COMPRESSED_RGB:
 367       if (format == GL_RGB && type == GL_UNSIGNED_SHORT_5_6_5) {
 368          if (pipe->is_format_supported( pipe, PIPE_FORMAT_U_R5_G6_B5 ))
 369             return PIPE_FORMAT_U_R5_G6_B5;
 370       }
 371       return default_rgba_format( pipe );
 372
 373    case GL_RGBA8:
 374    case GL_RGB10_A2:
 375    case GL_RGBA12:
 376       return default_rgba_format( pipe );
 377    case GL_RGBA16:
 378       return default_deep_rgba_format( pipe );
 379
 380    case GL_RGBA4:
 381    case GL_RGBA2:
 382       if (pipe->is_format_supported( pipe, PIPE_FORMAT_U_A4_R4_G4_B4 ))
 383          return PIPE_FORMAT_U_A4_R4_G4_B4;
 384       return default_rgba_format( pipe );
 385
 386    case GL_RGB5_A1:
 387       if (pipe->is_format_supported( pipe, PIPE_FORMAT_U_A1_R5_G5_B5 ))
 388          return PIPE_FORMAT_U_A1_R5_G5_B5;
 389       return default_rgba_format( pipe );
 390
 391    case GL_RGB8:
 392    case GL_RGB10:
 393    case GL_RGB12:
 394    case GL_RGB16:
 395       return default_rgba_format( pipe );
 396
 397    case GL_RGB5:
 398    case GL_RGB4:
 399    case GL_R3_G3_B2:
 400       if (pipe->is_format_supported( pipe, PIPE_FORMAT_U_A1_R5_G5_B5 ))
 401          return PIPE_FORMAT_U_A1_R5_G5_B5;
 402       return default_rgba_format( pipe );
 403
 404    case GL_ALPHA:
 405    case GL_ALPHA4:
 406    case GL_ALPHA8:
 407    case GL_ALPHA12:
 408    case GL_ALPHA16:
 409    case GL_COMPRESSED_ALPHA:
 410       if (pipe->is_format_supported( pipe, PIPE_FORMAT_U_A8 ))
 411          return PIPE_FORMAT_U_A8;
 412       return default_rgba_format( pipe );
 413
 414    case 1:
 415    case GL_LUMINANCE:
 416    case GL_LUMINANCE4:
 417    case GL_LUMINANCE8:
 418    case GL_LUMINANCE12:
 419    case GL_LUMINANCE16:
 420    case GL_COMPRESSED_LUMINANCE:
 421       if (pipe->is_format_supported( pipe, PIPE_FORMAT_U_A8 ))
 422          return PIPE_FORMAT_U_A8;
 423       return default_rgba_format( pipe );
 424
 425    case 2:
 426    case GL_LUMINANCE_ALPHA:
 427    case GL_LUMINANCE4_ALPHA4:
 428    case GL_LUMINANCE6_ALPHA2:
 429    case GL_LUMINANCE8_ALPHA8:
 430    case GL_LUMINANCE12_ALPHA4:
 431    case GL_LUMINANCE12_ALPHA12:
 432    case GL_LUMINANCE16_ALPHA16:
 433    case GL_COMPRESSED_LUMINANCE_ALPHA:
 434       if (pipe->is_format_supported( pipe, PIPE_FORMAT_U_A8_L8 ))
 435          return PIPE_FORMAT_U_A8_L8;
 436       return default_rgba_format( pipe );
 437
 438    case GL_INTENSITY:
 439    case GL_INTENSITY4:
 440    case GL_INTENSITY8:
 441    case GL_INTENSITY12:
 442    case GL_INTENSITY16:
 443    case GL_COMPRESSED_INTENSITY:
 444       if (pipe->is_format_supported( pipe, PIPE_FORMAT_U_I8 ))
 445          return PIPE_FORMAT_U_I8;
 446       return default_rgba_format( pipe );
 447
 448    case GL_YCBCR_MESA:
 449       if (type == GL_UNSIGNED_SHORT_8_8_MESA || type == GL_UNSIGNED_BYTE) {
 450          if (pipe->is_format_supported( pipe, PIPE_FORMAT_YCBCR ))
 451             return PIPE_FORMAT_YCBCR;
 452       }
 453       else {
 454          if (pipe->is_format_supported( pipe, PIPE_FORMAT_YCBCR_REV ))
 455             return PIPE_FORMAT_YCBCR_REV;
 456       }
 457       return PIPE_FORMAT_NONE;
 458
 459 #if 0
 460    case GL_COMPRESSED_RGB_FXT1_3DFX:
 461       return &_mesa_texformat_rgb_fxt1;
 462    case GL_COMPRESSED_RGBA_FXT1_3DFX:
 463       return &_mesa_texformat_rgba_fxt1;
 464
 465    case GL_RGB_S3TC:
 466    case GL_RGB4_S3TC:
 467    case GL_COMPRESSED_RGB_S3TC_DXT1_EXT:
 468       return &_mesa_texformat_rgb_dxt1;
 469
 470    case GL_COMPRESSED_RGBA_S3TC_DXT1_EXT:
 471       return &_mesa_texformat_rgba_dxt1;
 472
 473    case GL_RGBA_S3TC:
 474    case GL_RGBA4_S3TC:
 475    case GL_COMPRESSED_RGBA_S3TC_DXT3_EXT:
 476       return &_mesa_texformat_rgba_dxt3;
 477
 478    case GL_COMPRESSED_RGBA_S3TC_DXT5_EXT:
 479       return &_mesa_texformat_rgba_dxt5;
 480 #endif
 481
 482    case GL_DEPTH_COMPONENT16:
 483       if (pipe->is_format_supported( pipe, PIPE_FORMAT_U_Z16 ))
 484          return PIPE_FORMAT_U_Z16;
 485       /* fall-through */
 486    case GL_DEPTH_COMPONENT24:
 487       if (pipe->is_format_supported( pipe, PIPE_FORMAT_S8_Z24 ))
 488          return PIPE_FORMAT_S8_Z24;
 489       /* fall-through */
 490    case GL_DEPTH_COMPONENT32:
 491       if (pipe->is_format_supported( pipe, PIPE_FORMAT_U_Z32 ))
 492          return PIPE_FORMAT_U_Z32;
 493       /* fall-through */
 494    case GL_DEPTH_COMPONENT:
 495       return default_depth_format( pipe );
 496
 497    case GL_STENCIL_INDEX:
 498    case GL_STENCIL_INDEX1_EXT:
 499    case GL_STENCIL_INDEX4_EXT:
 500    case GL_STENCIL_INDEX8_EXT:
 501    case GL_STENCIL_INDEX16_EXT:
 502       if (pipe->is_format_supported( pipe, PIPE_FORMAT_U_S8 ))
 503          return PIPE_FORMAT_U_S8;
 504       if (pipe->is_format_supported( pipe, PIPE_FORMAT_S8_Z24 ))
 505          return PIPE_FORMAT_S8_Z24;
 506       return PIPE_FORMAT_NONE;
 507
 508    case GL_DEPTH_STENCIL_EXT:
 509    case GL_DEPTH24_STENCIL8_EXT:
 510       if (pipe->is_format_supported( pipe, PIPE_FORMAT_S8_Z24 ))
 511          return PIPE_FORMAT_S8_Z24;
 512       return PIPE_FORMAT_NONE;
 513
 514    default:
 515       return PIPE_FORMAT_NONE;
 516    }
 517 }
 518
 519
 520
 521 /* It works out that this function is fine for all the supported
 522  * hardware.  However, there is still a need to map the formats onto
 523  * hardware descriptors.
 524  */
 525 /* Note that the i915 can actually support many more formats than
 526  * these if we take the step of simply swizzling the colors
 527  * immediately after sampling...
 528  */
 529 const struct gl_texture_format *
 530 st_ChooseTextureFormat(GLcontext * ctx, GLint internalFormat,
 531                          GLenum format, GLenum type)
 532 {
 533 #if 0
 534    struct intel_context *intel = intel_context(ctx);
 535    const GLboolean do32bpt = (intel->intelScreen->front.cpp == 4);
 536 #else
 537    const GLboolean do32bpt = 1;
 538 #endif
 539
 540    switch (internalFormat) {
 541    case 4:
 542    case GL_RGBA:
 543    case GL_COMPRESSED_RGBA:
 544       if (format == GL_BGRA) {
 545          if (type == GL_UNSIGNED_BYTE || type == GL_UNSIGNED_INT_8_8_8_8_REV) {
 546             return &_mesa_texformat_argb8888;
 547          }
 548          else if (type == GL_UNSIGNED_SHORT_4_4_4_4_REV) {
 549             return &_mesa_texformat_argb4444;
 550          }
 551          else if (type == GL_UNSIGNED_SHORT_1_5_5_5_REV) {
 552             return &_mesa_texformat_argb1555;
 553          }
 554       }
 555       return do32bpt ? &_mesa_texformat_argb8888 : &_mesa_texformat_argb4444;
 556
 557    case 3:
 558    case GL_RGB:
 559    case GL_COMPRESSED_RGB:
 560       if (format == GL_RGB && type == GL_UNSIGNED_SHORT_5_6_5) {
 561          return &_mesa_texformat_rgb565;
 562       }
 563       return do32bpt ? &_mesa_texformat_argb8888 : &_mesa_texformat_rgb565;
 564
 565    case GL_RGBA8:
 566    case GL_RGB10_A2:
 567    case GL_RGBA12:
 568    case GL_RGBA16:
 569       return do32bpt ? &_mesa_texformat_argb8888 : &_mesa_texformat_argb4444;
 570
 571    case GL_RGBA4:
 572    case GL_RGBA2:
 573       return &_mesa_texformat_argb4444;
 574
 575    case GL_RGB5_A1:
 576       return &_mesa_texformat_argb1555;
 577
 578    case GL_RGB8:
 579    case GL_RGB10:
 580    case GL_RGB12:
 581    case GL_RGB16:
 582       return &_mesa_texformat_argb8888;
 583
 584    case GL_RGB5:
 585    case GL_RGB4:
 586    case GL_R3_G3_B2:
 587       return &_mesa_texformat_rgb565;
 588
 589    case GL_ALPHA:
 590    case GL_ALPHA4:
 591    case GL_ALPHA8:
 592    case GL_ALPHA12:
 593    case GL_ALPHA16:
 594    case GL_COMPRESSED_ALPHA:
 595       return &_mesa_texformat_a8;
 596
 597    case 1:
 598    case GL_LUMINANCE:
 599    case GL_LUMINANCE4:
 600    case GL_LUMINANCE8:
 601    case GL_LUMINANCE12:
 602    case GL_LUMINANCE16:
 603    case GL_COMPRESSED_LUMINANCE:
 604       return &_mesa_texformat_l8;
 605
 606    case 2:
 607    case GL_LUMINANCE_ALPHA:
 608    case GL_LUMINANCE4_ALPHA4:
 609    case GL_LUMINANCE6_ALPHA2:
 610    case GL_LUMINANCE8_ALPHA8:
 611    case GL_LUMINANCE12_ALPHA4:
 612    case GL_LUMINANCE12_ALPHA12:
 613    case GL_LUMINANCE16_ALPHA16:
 614    case GL_COMPRESSED_LUMINANCE_ALPHA:
 615       return &_mesa_texformat_al88;
 616
 617    case GL_INTENSITY:
 618    case GL_INTENSITY4:
 619    case GL_INTENSITY8:
 620    case GL_INTENSITY12:
 621    case GL_INTENSITY16:
 622    case GL_COMPRESSED_INTENSITY:
 623       return &_mesa_texformat_i8;
 624
 625    case GL_YCBCR_MESA:
 626       if (type == GL_UNSIGNED_SHORT_8_8_MESA || type == GL_UNSIGNED_BYTE)
 627          return &_mesa_texformat_ycbcr;
 628       else
 629          return &_mesa_texformat_ycbcr_rev;
 630
 631    case GL_COMPRESSED_RGB_FXT1_3DFX:
 632       return &_mesa_texformat_rgb_fxt1;
 633    case GL_COMPRESSED_RGBA_FXT1_3DFX:
 634       return &_mesa_texformat_rgba_fxt1;
 635
 636    case GL_RGB_S3TC:
 637    case GL_RGB4_S3TC:
 638    case GL_COMPRESSED_RGB_S3TC_DXT1_EXT:
 639       return &_mesa_texformat_rgb_dxt1;
 640
 641    case GL_COMPRESSED_RGBA_S3TC_DXT1_EXT:
 642       return &_mesa_texformat_rgba_dxt1;
 643
 644    case GL_RGBA_S3TC:
 645    case GL_RGBA4_S3TC:
 646    case GL_COMPRESSED_RGBA_S3TC_DXT3_EXT:
 647       return &_mesa_texformat_rgba_dxt3;
 648
 649    case GL_COMPRESSED_RGBA_S3TC_DXT5_EXT:
 650       return &_mesa_texformat_rgba_dxt5;
 651
 652    case GL_DEPTH_COMPONENT:
 653    case GL_DEPTH_COMPONENT16:
 654    case GL_DEPTH_COMPONENT24:
 655    case GL_DEPTH_COMPONENT32:
 656       return &_mesa_texformat_z16;
 657
 658    case GL_DEPTH_STENCIL_EXT:
 659    case GL_DEPTH24_STENCIL8_EXT:
 660       return &_mesa_texformat_z24_s8;
 661
 662    default:
 663       fprintf(stderr, "unexpected texture format %s in %s\n",
 664               _mesa_lookup_enum_by_nr(internalFormat), __FUNCTION__);
 665       return NULL;
 666    }
 667
 668    return NULL;                 /* never get here */
 669 }