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 "pipe/p_screen.h"
  44 #include "st_context.h"
  45 #include "st_format.h"
  46
  47 static GLuint
  48 format_bits(
  49    pipe_format_rgbazs_t  info,
  50    GLuint comp )
  51 {
  52    GLuint   size;
  53
  54    if (pf_swizzle_x(info) == comp) {
  55       size = pf_size_x(info);
  56    }
  57    else if (pf_swizzle_y(info) == comp) {
  58       size = pf_size_y(info);
  59    }
  60    else if (pf_swizzle_z(info) == comp) {
  61       size = pf_size_z(info);
  62    }
  63    else if (pf_swizzle_w(info) == comp) {
  64       size = pf_size_w(info);
  65    }
  66    else {
  67       size = 0;
  68    }
  69    return size << (pf_exp8(info) * 3);
  70 }
  71
  72 static GLuint
  73 format_max_bits(
  74    pipe_format_rgbazs_t  info )
  75 {
  76    GLuint   size = format_bits( info, PIPE_FORMAT_COMP_R );
  77
  78    size = MAX2( size, format_bits( info, PIPE_FORMAT_COMP_G ) );
  79    size = MAX2( size, format_bits( info, PIPE_FORMAT_COMP_B ) );
  80    size = MAX2( size, format_bits( info, PIPE_FORMAT_COMP_A ) );
  81    size = MAX2( size, format_bits( info, PIPE_FORMAT_COMP_Z ) );
  82    size = MAX2( size, format_bits( info, PIPE_FORMAT_COMP_S ) );
  83    return size;
  84 }
  85
  86 static GLuint
  87 format_size(
  88    pipe_format_rgbazs_t  info )
  89 {
  90    return
  91       format_bits( info, PIPE_FORMAT_COMP_R ) +
  92       format_bits( info, PIPE_FORMAT_COMP_G ) +
  93       format_bits( info, PIPE_FORMAT_COMP_B ) +
  94       format_bits( info, PIPE_FORMAT_COMP_A ) +
  95       format_bits( info, PIPE_FORMAT_COMP_Z ) +
  96       format_bits( info, PIPE_FORMAT_COMP_S );
  97 }
  98
  99 /*
 100  * XXX temporary here
 101  */
 102 GLboolean
 103 st_get_format_info(enum pipe_format format, struct pipe_format_info *pinfo)
 104 {
 105    if (pf_layout(format) == PIPE_FORMAT_LAYOUT_RGBAZS) {
 106       pipe_format_rgbazs_t info;
 107
 108       info = format;
 109
 110 #if 0
 111       {
 112          char  fmtname[256];
 113
 114          pf_sprint_name( fmtname, format );
 115          printf(
 116             "%s\n",
 117             fmtname );
 118       }
 119 #endif
 120
 121       /* Data type */
 122       if (format == PIPE_FORMAT_A1R5G5B5_UNORM || format == PIPE_FORMAT_R5G6B5_UNORM) {
 123          pinfo->datatype = GL_UNSIGNED_SHORT;
 124       }
 125       else {
 126          GLuint size;
 127
 128          size = format_max_bits( info );
 129          if (size == 8) {
 130             if (pf_type(info) == PIPE_FORMAT_TYPE_UNORM)
 131                pinfo->datatype = GL_UNSIGNED_BYTE;
 132             else
 133                pinfo->datatype = GL_BYTE;
 134          }
 135          else if (size == 16) {
 136             if (pf_type(info) == PIPE_FORMAT_TYPE_UNORM)
 137                pinfo->datatype = GL_UNSIGNED_SHORT;
 138             else
 139                pinfo->datatype = GL_SHORT;
 140          }
 141          else {
 142             assert( size <= 32 );
 143             if (pf_type(info) == PIPE_FORMAT_TYPE_UNORM)
 144                pinfo->datatype = GL_UNSIGNED_INT;
 145             else
 146                pinfo->datatype = GL_INT;
 147          }
 148       }
 149
 150       /* Component bits */
 151       pinfo->red_bits = format_bits( info, PIPE_FORMAT_COMP_R );
 152       pinfo->green_bits = format_bits( info, PIPE_FORMAT_COMP_G );
 153       pinfo->blue_bits = format_bits( info, PIPE_FORMAT_COMP_B );
 154       pinfo->alpha_bits = format_bits( info, PIPE_FORMAT_COMP_A );
 155       pinfo->depth_bits = format_bits( info, PIPE_FORMAT_COMP_Z );
 156       pinfo->stencil_bits = format_bits( info, PIPE_FORMAT_COMP_S );
 157       pinfo->luminance_bits = 0;
 158       pinfo->intensity_bits = 0;
 159
 160       /* Format size */
 161       pinfo->size = format_size( info ) / 8;
 162
 163       /* Luminance & Intensity bits */
 164       if( pf_swizzle_x(info) == PIPE_FORMAT_COMP_R &&
 165           pf_swizzle_y(info) == PIPE_FORMAT_COMP_R &&
 166           pf_swizzle_z(info) == PIPE_FORMAT_COMP_R ) {
 167          if( pf_swizzle_w(info) == PIPE_FORMAT_COMP_R ) {
 168             pinfo->intensity_bits = pinfo->red_bits;
 169          }
 170          else {
 171             pinfo->luminance_bits = pinfo->red_bits;
 172          }
 173          pinfo->red_bits = 0;
 174       }
 175
 176       /* Base format */
 177       if (pinfo->depth_bits) {
 178          if (pinfo->stencil_bits) {
 179             pinfo->base_format = GL_DEPTH_STENCIL_EXT;
 180          }
 181          else {
 182             pinfo->base_format = GL_DEPTH_COMPONENT;
 183          }
 184       }
 185       else if (pinfo->stencil_bits) {
 186          pinfo->base_format = GL_STENCIL_INDEX;
 187       }
 188       else {
 189          pinfo->base_format = GL_RGBA;
 190       }
 191    }
 192    else if (pf_layout(format) == PIPE_FORMAT_LAYOUT_YCBCR) {
 193       pinfo->base_format = GL_YCBCR_MESA;
 194       pinfo->datatype = GL_UNSIGNED_SHORT;
 195       pinfo->size = 2; /* two bytes per "texel" */
 196    }
 197    else {
 198       /* compressed format? */
 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(enum pipe_format format)
 224 {
 225    struct pipe_format_info info;
 226    if (!st_get_format_info( format, &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(enum pipe_format format)
 239 {
 240    struct pipe_format_info info;
 241    if (!st_get_format_info( format, &info )) {
 242       assert( 0 );
 243       return 0;
 244    }
 245    return info.datatype;
 246 }
 247
 248
 249 enum pipe_format
 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_A8R8G8B8_UNORM;
 257    case MESA_FORMAT_ARGB1555:
 258       return PIPE_FORMAT_A1R5G5B5_UNORM;
 259    case MESA_FORMAT_ARGB4444:
 260       return PIPE_FORMAT_A4R4G4B4_UNORM;
 261    case MESA_FORMAT_RGB565:
 262       return PIPE_FORMAT_R5G6B5_UNORM;
 263    case MESA_FORMAT_AL88:
 264       return PIPE_FORMAT_A8L8_UNORM;
 265    case MESA_FORMAT_A8:
 266       return PIPE_FORMAT_A8_UNORM;
 267    case MESA_FORMAT_L8:
 268       return PIPE_FORMAT_L8_UNORM;
 269    case MESA_FORMAT_I8:
 270       return PIPE_FORMAT_I8_UNORM;
 271    case MESA_FORMAT_Z16:
 272       return PIPE_FORMAT_Z16_UNORM;
 273    case MESA_FORMAT_Z32:
 274       return PIPE_FORMAT_Z32_UNORM;
 275    case MESA_FORMAT_Z24_S8:
 276       return PIPE_FORMAT_Z24S8_UNORM;
 277    case MESA_FORMAT_S8_Z24:
 278       return PIPE_FORMAT_S8Z24_UNORM;
 279    case MESA_FORMAT_YCBCR:
 280       return PIPE_FORMAT_YCBCR;
 281    case MESA_FORMAT_RGB_DXT1:
 282       return PIPE_FORMAT_DXT1_RGB;
 283    case MESA_FORMAT_RGBA_DXT1:
 284       return PIPE_FORMAT_DXT1_RGBA;
 285    case MESA_FORMAT_RGBA_DXT3:
 286       return PIPE_FORMAT_DXT3_RGBA;
 287    case MESA_FORMAT_RGBA_DXT5:
 288       return PIPE_FORMAT_DXT5_RGBA;
 289    default:
 290       assert(0);
 291       return 0;
 292    }
 293 }
 294
 295 /**
 296  * Find an RGBA format supported by the context/winsys.
 297  */
 298 static enum pipe_format
 299 default_rgba_format(struct pipe_screen *screen, uint type)
 300 {
 301    static const enum pipe_format colorFormats[] = {
 302       PIPE_FORMAT_A8R8G8B8_UNORM,
 303       PIPE_FORMAT_B8G8R8A8_UNORM,
 304       PIPE_FORMAT_R8G8B8A8_UNORM,
 305       PIPE_FORMAT_R5G6B5_UNORM
 306    };
 307    uint i;
 308    for (i = 0; i < Elements(colorFormats); i++) {
 309       if (screen->is_format_supported( screen, colorFormats[i], type )) {
 310          return colorFormats[i];
 311       }
 312    }
 313    return PIPE_FORMAT_NONE;
 314 }
 315
 316
 317 /**
 318  * Search list of formats for first RGBA format with >8 bits/channel.
 319  */
 320 static enum pipe_format
 321 default_deep_rgba_format(struct pipe_screen *screen, uint type)
 322 {
 323    if (screen->is_format_supported(screen, PIPE_FORMAT_R16G16B16A16_SNORM, type)) {
 324       return PIPE_FORMAT_R16G16B16A16_SNORM;
 325    }
 326    if (type == PIPE_TEXTURE)
 327       return default_rgba_format(screen, type);
 328    else
 329       return PIPE_FORMAT_NONE;
 330 }
 331
 332
 333 /**
 334  * Find an Z format supported by the context/winsys.
 335  */
 336 static enum pipe_format
 337 default_depth_format(struct pipe_screen *screen, uint type)
 338 {
 339    static const enum pipe_format zFormats[] = {
 340       PIPE_FORMAT_Z16_UNORM,
 341       PIPE_FORMAT_Z32_UNORM,
 342       PIPE_FORMAT_S8Z24_UNORM,
 343       PIPE_FORMAT_Z24S8_UNORM
 344    };
 345    uint i;
 346    for (i = 0; i < Elements(zFormats); i++) {
 347       if (screen->is_format_supported( screen, zFormats[i], type )) {
 348          return zFormats[i];
 349       }
 350    }
 351    return PIPE_FORMAT_NONE;
 352 }
 353
 354
 355 /**
 356  * Given an OpenGL internalFormat value for a texture or surface, return
 357  * the best matching PIPE_FORMAT_x, or PIPE_FORMAT_NONE if there's no match.
 358  */
 359 enum pipe_format
 360 st_choose_format(struct pipe_context *pipe, GLint internalFormat,
 361                  uint surfType)
 362 {
 363    struct pipe_screen *screen = pipe->screen;
 364
 365    assert(surfType == PIPE_SURFACE ||
 366           surfType == PIPE_TEXTURE);
 367
 368    switch (internalFormat) {
 369    case 4:
 370    case GL_RGBA:
 371    case GL_COMPRESSED_RGBA:
 372    case 3:
 373    case GL_RGB:
 374    case GL_COMPRESSED_RGB:
 375    case GL_RGBA8:
 376    case GL_RGB10_A2:
 377    case GL_RGBA12:
 378       return default_rgba_format( screen, surfType );
 379    case GL_RGBA16:
 380       return default_deep_rgba_format( screen, surfType );
 381
 382    case GL_RGBA4:
 383    case GL_RGBA2:
 384       if (screen->is_format_supported( screen, PIPE_FORMAT_A4R4G4B4_UNORM, surfType ))
 385          return PIPE_FORMAT_A4R4G4B4_UNORM;
 386       return default_rgba_format( screen, surfType );
 387
 388    case GL_RGB5_A1:
 389       if (screen->is_format_supported( screen, PIPE_FORMAT_A1R5G5B5_UNORM, surfType ))
 390          return PIPE_FORMAT_A1R5G5B5_UNORM;
 391       return default_rgba_format( screen, surfType );
 392
 393    case GL_RGB8:
 394    case GL_RGB10:
 395    case GL_RGB12:
 396    case GL_RGB16:
 397       return default_rgba_format( screen, surfType );
 398
 399    case GL_RGB5:
 400    case GL_RGB4:
 401    case GL_R3_G3_B2:
 402       if (screen->is_format_supported( screen, PIPE_FORMAT_A1R5G5B5_UNORM, surfType ))
 403          return PIPE_FORMAT_A1R5G5B5_UNORM;
 404       if (screen->is_format_supported( screen, PIPE_FORMAT_R5G6B5_UNORM, surfType ))
 405          return PIPE_FORMAT_R5G6B5_UNORM;
 406       return default_rgba_format( screen, surfType );
 407
 408    case GL_ALPHA:
 409    case GL_ALPHA4:
 410    case GL_ALPHA8:
 411    case GL_ALPHA12:
 412    case GL_ALPHA16:
 413    case GL_COMPRESSED_ALPHA:
 414       if (screen->is_format_supported( screen, PIPE_FORMAT_A8_UNORM, surfType ))
 415          return PIPE_FORMAT_A8_UNORM;
 416       return default_rgba_format( screen, surfType );
 417
 418    case 1:
 419    case GL_LUMINANCE:
 420    case GL_LUMINANCE4:
 421    case GL_LUMINANCE8:
 422    case GL_LUMINANCE12:
 423    case GL_LUMINANCE16:
 424    case GL_COMPRESSED_LUMINANCE:
 425       if (screen->is_format_supported( screen, PIPE_FORMAT_L8_UNORM, surfType ))
 426          return PIPE_FORMAT_L8_UNORM;
 427       return default_rgba_format( screen, surfType );
 428
 429    case 2:
 430    case GL_LUMINANCE_ALPHA:
 431    case GL_LUMINANCE4_ALPHA4:
 432    case GL_LUMINANCE6_ALPHA2:
 433    case GL_LUMINANCE8_ALPHA8:
 434    case GL_LUMINANCE12_ALPHA4:
 435    case GL_LUMINANCE12_ALPHA12:
 436    case GL_LUMINANCE16_ALPHA16:
 437    case GL_COMPRESSED_LUMINANCE_ALPHA:
 438       if (screen->is_format_supported( screen, PIPE_FORMAT_A8L8_UNORM, surfType ))
 439          return PIPE_FORMAT_A8L8_UNORM;
 440       return default_rgba_format( screen, surfType );
 441
 442    case GL_INTENSITY:
 443    case GL_INTENSITY4:
 444    case GL_INTENSITY8:
 445    case GL_INTENSITY12:
 446    case GL_INTENSITY16:
 447    case GL_COMPRESSED_INTENSITY:
 448       if (screen->is_format_supported( screen, PIPE_FORMAT_I8_UNORM, surfType ))
 449          return PIPE_FORMAT_I8_UNORM;
 450       return default_rgba_format( screen, surfType );
 451
 452    case GL_YCBCR_MESA:
 453       if (screen->is_format_supported(screen, PIPE_FORMAT_YCBCR,
 454                                       PIPE_TEXTURE)) {
 455          return PIPE_FORMAT_YCBCR;
 456       }
 457       if (screen->is_format_supported(screen, PIPE_FORMAT_YCBCR_REV,
 458                                       PIPE_TEXTURE)) {
 459          return PIPE_FORMAT_YCBCR_REV;
 460       }
 461       return PIPE_FORMAT_NONE;
 462
 463    case GL_RGB_S3TC:
 464    case GL_RGB4_S3TC:
 465    case GL_COMPRESSED_RGB_S3TC_DXT1_EXT:
 466       return PIPE_FORMAT_DXT1_RGB;
 467
 468    case GL_COMPRESSED_RGBA_S3TC_DXT1_EXT:
 469       return PIPE_FORMAT_DXT1_RGBA;
 470
 471    case GL_RGBA_S3TC:
 472    case GL_RGBA4_S3TC:
 473    case GL_COMPRESSED_RGBA_S3TC_DXT3_EXT:
 474       return PIPE_FORMAT_DXT3_RGBA;
 475
 476    case GL_COMPRESSED_RGBA_S3TC_DXT5_EXT:
 477       return PIPE_FORMAT_DXT5_RGBA;
 478
 479 #if 0
 480    case GL_COMPRESSED_RGB_FXT1_3DFX:
 481       return PIPE_FORMAT_RGB_FXT1;
 482    case GL_COMPRESSED_RGBA_FXT1_3DFX:
 483       return PIPE_FORMAT_RGB_FXT1;
 484 #endif
 485
 486    case GL_DEPTH_COMPONENT16:
 487       if (screen->is_format_supported( screen, PIPE_FORMAT_Z16_UNORM, surfType ))
 488          return PIPE_FORMAT_Z16_UNORM;
 489       /* fall-through */
 490    case GL_DEPTH_COMPONENT24:
 491       if (screen->is_format_supported( screen, PIPE_FORMAT_S8Z24_UNORM, surfType ))
 492          return PIPE_FORMAT_S8Z24_UNORM;
 493       if (screen->is_format_supported( screen, PIPE_FORMAT_Z24S8_UNORM, surfType ))
 494          return PIPE_FORMAT_Z24S8_UNORM;
 495       /* fall-through */
 496    case GL_DEPTH_COMPONENT32:
 497       if (screen->is_format_supported( screen, PIPE_FORMAT_Z32_UNORM, surfType ))
 498          return PIPE_FORMAT_Z32_UNORM;
 499       /* fall-through */
 500    case GL_DEPTH_COMPONENT:
 501       return default_depth_format( screen, surfType );
 502
 503    case GL_STENCIL_INDEX:
 504    case GL_STENCIL_INDEX1_EXT:
 505    case GL_STENCIL_INDEX4_EXT:
 506    case GL_STENCIL_INDEX8_EXT:
 507    case GL_STENCIL_INDEX16_EXT:
 508       if (screen->is_format_supported( screen, PIPE_FORMAT_S8_UNORM, surfType ))
 509          return PIPE_FORMAT_S8_UNORM;
 510       if (screen->is_format_supported( screen, PIPE_FORMAT_S8Z24_UNORM, surfType ))
 511          return PIPE_FORMAT_S8Z24_UNORM;
 512       if (screen->is_format_supported( screen, PIPE_FORMAT_Z24S8_UNORM, surfType ))
 513          return PIPE_FORMAT_Z24S8_UNORM;
 514       return PIPE_FORMAT_NONE;
 515
 516    case GL_DEPTH_STENCIL_EXT:
 517    case GL_DEPTH24_STENCIL8_EXT:
 518       if (screen->is_format_supported( screen, PIPE_FORMAT_S8Z24_UNORM, surfType ))
 519          return PIPE_FORMAT_S8Z24_UNORM;
 520       if (screen->is_format_supported( screen, PIPE_FORMAT_Z24S8_UNORM, surfType ))
 521          return PIPE_FORMAT_Z24S8_UNORM;
 522       return PIPE_FORMAT_NONE;
 523
 524    default:
 525       return PIPE_FORMAT_NONE;
 526    }
 527 }
 528
 529
 530 /**
 531  * Called by FBO code to choose a PIPE_FORMAT_ for drawing surfaces.
 532  */
 533 enum pipe_format
 534 st_choose_renderbuffer_format(struct pipe_context *pipe, GLint internalFormat)
 535 {
 536    return st_choose_format(pipe, internalFormat, PIPE_SURFACE);
 537 }
 538
 539
 540 static const struct gl_texture_format *
 541 translate_gallium_format_to_mesa_format(enum pipe_format format)
 542 {
 543    switch (format) {
 544    case PIPE_FORMAT_A8R8G8B8_UNORM:
 545       return &_mesa_texformat_argb8888;
 546    case PIPE_FORMAT_A1R5G5B5_UNORM:
 547       return &_mesa_texformat_argb1555;
 548    case PIPE_FORMAT_A4R4G4B4_UNORM:
 549       return &_mesa_texformat_argb4444;
 550    case PIPE_FORMAT_R5G6B5_UNORM:
 551       return &_mesa_texformat_rgb565;
 552    case PIPE_FORMAT_A8L8_UNORM:
 553       return &_mesa_texformat_al88;
 554    case PIPE_FORMAT_A8_UNORM:
 555       return &_mesa_texformat_a8;
 556    case PIPE_FORMAT_L8_UNORM:
 557       return &_mesa_texformat_l8;
 558    case PIPE_FORMAT_I8_UNORM:
 559       return &_mesa_texformat_i8;
 560    case PIPE_FORMAT_Z16_UNORM:
 561       return &_mesa_texformat_z16;
 562    case PIPE_FORMAT_Z32_UNORM:
 563       return &_mesa_texformat_z32;
 564    case PIPE_FORMAT_Z24S8_UNORM:
 565       return &_mesa_texformat_z24_s8;
 566    case PIPE_FORMAT_S8Z24_UNORM:
 567       return &_mesa_texformat_s8_z24;
 568    case PIPE_FORMAT_YCBCR:
 569       return &_mesa_texformat_ycbcr;
 570    case PIPE_FORMAT_YCBCR_REV:
 571       return &_mesa_texformat_ycbcr_rev;
 572    case PIPE_FORMAT_DXT1_RGB:
 573       return &_mesa_texformat_rgb_dxt1;
 574    case PIPE_FORMAT_DXT1_RGBA:
 575       return &_mesa_texformat_rgba_dxt1;
 576    case PIPE_FORMAT_DXT3_RGBA:
 577       return &_mesa_texformat_rgba_dxt3;
 578    case PIPE_FORMAT_DXT5_RGBA:
 579       return &_mesa_texformat_rgba_dxt5;
 580    /* XXX add additional cases */
 581    default:
 582       assert(0);
 583       return NULL;
 584    }
 585 }
 586
 587
 588 /**
 589  * Called via ctx->Driver.chooseTextureFormat().
 590  */
 591 const struct gl_texture_format *
 592 st_ChooseTextureFormat(GLcontext *ctx, GLint internalFormat,
 593                        GLenum format, GLenum type)
 594 {
 595    enum pipe_format pFormat;
 596
 597    (void) format;
 598    (void) type;
 599
 600    pFormat = st_choose_format(ctx->st->pipe, internalFormat, PIPE_TEXTURE);
 601    if (pFormat == PIPE_FORMAT_NONE)
 602       return NULL;
 603
 604    return translate_gallium_format_to_mesa_format(pFormat);
 605 }