src/gallium/auxiliary/util/u_format.h

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   3  * Copyright 2009-2010 Vmware, Inc.
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  27
  28
  29 #ifndef U_FORMAT_H
  30 #define U_FORMAT_H
  31
  32
  33 #include "pipe/p_format.h"
  34 #include "util/u_debug.h"
  35
  36 #ifdef __cplusplus
  37 extern "C" {
  38 #endif
  39
  40
  41 /**
  42  * Describe how to pack/unpack pixels into/from the prescribed format.
  43  *
  44  * XXX: This could be renamed to something like util_format_pack, or broke down
  45  * in flags inside util_format_block that said exactly what we want.
  46  */
  47 enum util_format_layout {
  48    /**
  49     * Formats with util_format_block::width == util_format_block::height == 1
  50     * that can be described as an ordinary data structure.
  51     */
  52    UTIL_FORMAT_LAYOUT_PLAIN = 0,
  53
  54    /**
  55     * Formats with sub-sampled channels.
  56     *
  57     * This is for formats like YV12 where there is less than one sample per
  58     * pixel.
  59     */
  60    UTIL_FORMAT_LAYOUT_SUBSAMPLED = 3,
  61
  62    /**
  63     * S3 Texture Compression formats.
  64     */
  65    UTIL_FORMAT_LAYOUT_S3TC = 4,
  66
  67    /**
  68     * Red-Green Texture Compression formats.
  69     */
  70    UTIL_FORMAT_LAYOUT_RGTC = 5,
  71
  72    /**
  73     * Everything else that doesn't fit in any of the above layouts.
  74     */
  75    UTIL_FORMAT_LAYOUT_OTHER = 6
  76 };
  77
  78
  79 struct util_format_block
  80 {
  81    /** Block width in pixels */
  82    unsigned width;
  83
  84    /** Block height in pixels */
  85    unsigned height;
  86
  87    /** Block size in bits */
  88    unsigned bits;
  89 };
  90
  91
  92 enum util_format_type {
  93    UTIL_FORMAT_TYPE_VOID = 0,
  94    UTIL_FORMAT_TYPE_UNSIGNED = 1,
  95    UTIL_FORMAT_TYPE_SIGNED = 2,
  96    UTIL_FORMAT_TYPE_FIXED = 3,
  97    UTIL_FORMAT_TYPE_FLOAT = 4
  98 };
  99
 100
 101 enum util_format_swizzle {
 102    UTIL_FORMAT_SWIZZLE_X = 0,
 103    UTIL_FORMAT_SWIZZLE_Y = 1,
 104    UTIL_FORMAT_SWIZZLE_Z = 2,
 105    UTIL_FORMAT_SWIZZLE_W = 3,
 106    UTIL_FORMAT_SWIZZLE_0 = 4,
 107    UTIL_FORMAT_SWIZZLE_1 = 5,
 108    UTIL_FORMAT_SWIZZLE_NONE = 6
 109 };
 110
 111
 112 enum util_format_colorspace {
 113    UTIL_FORMAT_COLORSPACE_RGB = 0,
 114    UTIL_FORMAT_COLORSPACE_SRGB = 1,
 115    UTIL_FORMAT_COLORSPACE_YUV = 2,
 116    UTIL_FORMAT_COLORSPACE_ZS = 3
 117 };
 118
 119
 120 struct util_format_channel_description
 121 {
 122    unsigned type:6;
 123    unsigned normalized:1;
 124    unsigned size:9;
 125 };
 126
 127
 128 struct util_format_description
 129 {
 130    enum pipe_format format;
 131
 132    const char *name;
 133
 134    /**
 135     * Short name, striped of the prefix, lower case.
 136     */
 137    const char *short_name;
 138
 139    /**
 140     * Pixel block dimensions.
 141     */
 142    struct util_format_block block;
 143
 144    enum util_format_layout layout;
 145
 146    /**
 147     * The number of channels.
 148     */
 149    unsigned nr_channels:3;
 150
 151    /**
 152     * Whether all channels have the same number of (whole) bytes.
 153     */
 154    unsigned is_array:1;
 155
 156    /**
 157     * Whether the pixel format can be described as a bitfield structure.
 158     *
 159     * In particular:
 160     * - pixel depth must be 8, 16, or 32 bits;
 161     * - all channels must be unsigned, signed, or void
 162     */
 163    unsigned is_bitmask:1;
 164
 165    /**
 166     * Whether channels have mixed types (ignoring UTIL_FORMAT_TYPE_VOID).
 167     */
 168    unsigned is_mixed:1;
 169
 170    /**
 171     * Input channel description.
 172     *
 173     * Only valid for UTIL_FORMAT_LAYOUT_PLAIN formats.
 174     */
 175    struct util_format_channel_description channel[4];
 176
 177    /**
 178     * Output channel swizzle.
 179     *
 180     * The order is either:
 181     * - RGBA
 182     * - YUV(A)
 183     * - ZS
 184     * depending on the colorspace.
 185     */
 186    unsigned char swizzle[4];
 187
 188    /**
 189     * Colorspace transformation.
 190     */
 191    enum util_format_colorspace colorspace;
 192
 193    /**
 194     * Unpack pixel blocks to R8G8B8A8_UNORM.
 195     * Note: strides are in bytes.
 196     *
 197     * Only defined for non-depth-stencil formats.
 198     */
 199    void
 200    (*unpack_rgba_8unorm)(uint8_t *dst, unsigned dst_stride,
 201                          const uint8_t *src, unsigned src_stride,
 202                          unsigned width, unsigned height);
 203
 204    /**
 205     * Pack pixel blocks from R8G8B8A8_UNORM.
 206     * Note: strides are in bytes.
 207     *
 208     * Only defined for non-depth-stencil formats.
 209     */
 210    void
 211    (*pack_rgba_8unorm)(uint8_t *dst, unsigned dst_stride,
 212                        const uint8_t *src, unsigned src_stride,
 213                        unsigned width, unsigned height);
 214
 215    /**
 216     * Fetch a single pixel (i, j) from a block.
 217     *
 218     * XXX: Only defined for a very few select formats.
 219     */
 220    void
 221    (*fetch_rgba_8unorm)(uint8_t *dst,
 222                         const uint8_t *src,
 223                         unsigned i, unsigned j);
 224
 225    /**
 226     * Unpack pixel blocks to R32G32B32A32_FLOAT.
 227     * Note: strides are in bytes.
 228     *
 229     * Only defined for non-depth-stencil formats.
 230     */
 231    void
 232    (*unpack_rgba_float)(float *dst, unsigned dst_stride,
 233                         const uint8_t *src, unsigned src_stride,
 234                         unsigned width, unsigned height);
 235
 236    /**
 237     * Pack pixel blocks from R32G32B32A32_FLOAT.
 238     * Note: strides are in bytes.
 239     *
 240     * Only defined for non-depth-stencil formats.
 241     */
 242    void
 243    (*pack_rgba_float)(uint8_t *dst, unsigned dst_stride,
 244                       const float *src, unsigned src_stride,
 245                       unsigned width, unsigned height);
 246
 247    /**
 248     * Fetch a single pixel (i, j) from a block.
 249     *
 250     * Only defined for non-depth-stencil formats.
 251     */
 252    void
 253    (*fetch_rgba_float)(float *dst,
 254                        const uint8_t *src,
 255                        unsigned i, unsigned j);
 256
 257    /**
 258     * Unpack pixels to Z32_UNORM.
 259     * Note: strides are in bytes.
 260     *
 261     * Only defined for depth formats.
 262     */
 263    void
 264    (*unpack_z_32unorm)(uint32_t *dst, unsigned dst_stride,
 265                        const uint8_t *src, unsigned src_stride,
 266                        unsigned width, unsigned height);
 267
 268    /**
 269     * Pack pixels from Z32_FLOAT.
 270     * Note: strides are in bytes.
 271     *
 272     * Only defined for depth formats.
 273     */
 274    void
 275    (*pack_z_32unorm)(uint8_t *dst, unsigned dst_stride,
 276                      const uint32_t *src, unsigned src_stride,
 277                      unsigned width, unsigned height);
 278
 279    /**
 280     * Unpack pixels to Z32_FLOAT.
 281     * Note: strides are in bytes.
 282     *
 283     * Only defined for depth formats.
 284     */
 285    void
 286    (*unpack_z_float)(float *dst, unsigned dst_stride,
 287                      const uint8_t *src, unsigned src_stride,
 288                      unsigned width, unsigned height);
 289
 290    /**
 291     * Pack pixels from Z32_FLOAT.
 292     * Note: strides are in bytes.
 293     *
 294     * Only defined for depth formats.
 295     */
 296    void
 297    (*pack_z_float)(uint8_t *dst, unsigned dst_stride,
 298                    const float *src, unsigned src_stride,
 299                    unsigned width, unsigned height);
 300
 301    /**
 302     * Unpack pixels to S8_USCALED.
 303     * Note: strides are in bytes.
 304     *
 305     * Only defined for stencil formats.
 306     */
 307    void
 308    (*unpack_s_8uscaled)(uint8_t *dst, unsigned dst_stride,
 309                         const uint8_t *src, unsigned src_stride,
 310                         unsigned width, unsigned height);
 311
 312    /**
 313     * Pack pixels from S8_USCALED.
 314     * Note: strides are in bytes.
 315     *
 316     * Only defined for stencil formats.
 317     */
 318    void
 319    (*pack_s_8uscaled)(uint8_t *dst, unsigned dst_stride,
 320                       const uint8_t *src, unsigned src_stride,
 321                       unsigned width, unsigned height);
 322
 323 };
 324
 325
 326 extern const struct util_format_description
 327 util_format_description_table[];
 328
 329
 330 const struct util_format_description *
 331 util_format_description(enum pipe_format format);
 332
 333
 334 /*
 335  * Format query functions.
 336  */
 337
 338 static INLINE const char *
 339 util_format_name(enum pipe_format format)
 340 {
 341    const struct util_format_description *desc = util_format_description(format);
 342
 343    assert(desc);
 344    if (!desc) {
 345       return "PIPE_FORMAT_???";
 346    }
 347
 348    return desc->name;
 349 }
 350
 351 static INLINE const char *
 352 util_format_short_name(enum pipe_format format)
 353 {
 354    const struct util_format_description *desc = util_format_description(format);
 355
 356    assert(desc);
 357    if (!desc) {
 358       return "???";
 359    }
 360
 361    return desc->short_name;
 362 }
 363
 364 /**
 365  * Whether this format is plain, see UTIL_FORMAT_LAYOUT_PLAIN for more info.
 366  */
 367 static INLINE boolean
 368 util_format_is_plain(enum pipe_format format)
 369 {
 370    const struct util_format_description *desc = util_format_description(format);
 371
 372    if (!format) {
 373       return FALSE;
 374    }
 375
 376    return desc->layout == UTIL_FORMAT_LAYOUT_PLAIN ? TRUE : FALSE;
 377 }
 378
 379 static INLINE boolean
 380 util_format_is_compressed(enum pipe_format format)
 381 {
 382    const struct util_format_description *desc = util_format_description(format);
 383
 384    assert(desc);
 385    if (!desc) {
 386       return FALSE;
 387    }
 388
 389    switch (desc->layout) {
 390    case UTIL_FORMAT_LAYOUT_S3TC:
 391    case UTIL_FORMAT_LAYOUT_RGTC:
 392       /* XXX add other formats in the future */
 393       return TRUE;
 394    default:
 395       return FALSE;
 396    }
 397 }
 398
 399 static INLINE boolean
 400 util_format_is_s3tc(enum pipe_format format)
 401 {
 402    const struct util_format_description *desc = util_format_description(format);
 403
 404    assert(desc);
 405    if (!desc) {
 406       return FALSE;
 407    }
 408
 409    return desc->layout == UTIL_FORMAT_LAYOUT_S3TC ? TRUE : FALSE;
 410 }
 411
 412 static INLINE boolean
 413 util_format_is_depth_or_stencil(enum pipe_format format)
 414 {
 415    const struct util_format_description *desc = util_format_description(format);
 416
 417    assert(desc);
 418    if (!desc) {
 419       return FALSE;
 420    }
 421
 422    return desc->colorspace == UTIL_FORMAT_COLORSPACE_ZS ? TRUE : FALSE;
 423 }
 424
 425 static INLINE boolean
 426 util_format_is_depth_and_stencil(enum pipe_format format)
 427 {
 428    const struct util_format_description *desc = util_format_description(format);
 429
 430    assert(desc);
 431    if (!desc) {
 432       return FALSE;
 433    }
 434
 435    if (desc->colorspace != UTIL_FORMAT_COLORSPACE_ZS) {
 436       return FALSE;
 437    }
 438
 439    return (desc->swizzle[0] != UTIL_FORMAT_SWIZZLE_NONE &&
 440            desc->swizzle[1] != UTIL_FORMAT_SWIZZLE_NONE) ? TRUE : FALSE;
 441 }
 442
 443
 444 /**
 445  * Give the RGBA colormask of the channels that can be represented in this
 446  * format.
 447  *
 448  * That is, the channels whose values are preserved.
 449  */
 450 static INLINE unsigned
 451 util_format_colormask(const struct util_format_description *desc)
 452 {
 453    unsigned colormask;
 454    unsigned chan;
 455
 456    switch (desc->colorspace) {
 457    case UTIL_FORMAT_COLORSPACE_RGB:
 458    case UTIL_FORMAT_COLORSPACE_SRGB:
 459    case UTIL_FORMAT_COLORSPACE_YUV:
 460       colormask = 0;
 461       for (chan = 0; chan < 4; ++chan) {
 462          if (desc->swizzle[chan] < 4) {
 463             colormask |= (1 << chan);
 464          }
 465       }
 466       return colormask;
 467    case UTIL_FORMAT_COLORSPACE_ZS:
 468       return 0;
 469    default:
 470       assert(0);
 471       return 0;
 472    }
 473 }
 474
 475
 476 /**
 477  * Whether the src format can be blitted to destation format with a simple
 478  * memcpy.
 479  */
 480 boolean
 481 util_is_format_compatible(const struct util_format_description *src_desc,
 482                           const struct util_format_description *dst_desc);
 483
 484
 485 /**
 486  * Whether this format is a rgab8 variant.
 487  *
 488  * That is, any format that matches the
 489  *
 490  *   PIPE_FORMAT_?8?8?8?8_UNORM
 491  */
 492 static INLINE boolean
 493 util_format_is_rgba8_variant(const struct util_format_description *desc)
 494 {
 495    unsigned chan;
 496
 497    if(desc->block.width != 1 ||
 498       desc->block.height != 1 ||
 499       desc->block.bits != 32)
 500       return FALSE;
 501
 502    for(chan = 0; chan < 4; ++chan) {
 503       if(desc->channel[chan].type != UTIL_FORMAT_TYPE_UNSIGNED &&
 504          desc->channel[chan].type != UTIL_FORMAT_TYPE_VOID)
 505          return FALSE;
 506       if(desc->channel[chan].size != 8)
 507          return FALSE;
 508    }
 509
 510    return TRUE;
 511 }
 512
 513
 514 /**
 515  * Return total bits needed for the pixel format per block.
 516  */
 517 static INLINE uint
 518 util_format_get_blocksizebits(enum pipe_format format)
 519 {
 520    const struct util_format_description *desc = util_format_description(format);
 521
 522    assert(desc);
 523    if (!desc) {
 524       return 0;
 525    }
 526
 527    return desc->block.bits;
 528 }
 529
 530 /**
 531  * Return bytes per block (not pixel) for the given format.
 532  */
 533 static INLINE uint
 534 util_format_get_blocksize(enum pipe_format format)
 535 {
 536    uint bits = util_format_get_blocksizebits(format);
 537
 538    assert(bits % 8 == 0);
 539
 540    return bits / 8;
 541 }
 542
 543 static INLINE uint
 544 util_format_get_blockwidth(enum pipe_format format)
 545 {
 546    const struct util_format_description *desc = util_format_description(format);
 547
 548    assert(desc);
 549    if (!desc) {
 550       return 1;
 551    }
 552
 553    return desc->block.width;
 554 }
 555
 556 static INLINE uint
 557 util_format_get_blockheight(enum pipe_format format)
 558 {
 559    const struct util_format_description *desc = util_format_description(format);
 560
 561    assert(desc);
 562    if (!desc) {
 563       return 1;
 564    }
 565
 566    return desc->block.height;
 567 }
 568
 569 static INLINE unsigned
 570 util_format_get_nblocksx(enum pipe_format format,
 571                          unsigned x)
 572 {
 573    unsigned blockwidth = util_format_get_blockwidth(format);
 574    return (x + blockwidth - 1) / blockwidth;
 575 }
 576
 577 static INLINE unsigned
 578 util_format_get_nblocksy(enum pipe_format format,
 579                          unsigned y)
 580 {
 581    unsigned blockheight = util_format_get_blockheight(format);
 582    return (y + blockheight - 1) / blockheight;
 583 }
 584
 585 static INLINE unsigned
 586 util_format_get_nblocks(enum pipe_format format,
 587                         unsigned width,
 588                         unsigned height)
 589 {
 590    return util_format_get_nblocksx(format, width) * util_format_get_nblocksy(format, height);
 591 }
 592
 593 static INLINE size_t
 594 util_format_get_stride(enum pipe_format format,
 595                        unsigned width)
 596 {
 597    return util_format_get_nblocksx(format, width) * util_format_get_blocksize(format);
 598 }
 599
 600 static INLINE size_t
 601 util_format_get_2d_size(enum pipe_format format,
 602                         size_t stride,
 603                         unsigned height)
 604 {
 605    return util_format_get_nblocksy(format, height) * stride;
 606 }
 607
 608 static INLINE uint
 609 util_format_get_component_bits(enum pipe_format format,
 610                                enum util_format_colorspace colorspace,
 611                                uint component)
 612 {
 613    const struct util_format_description *desc = util_format_description(format);
 614    enum util_format_colorspace desc_colorspace;
 615
 616    assert(format);
 617    if (!format) {
 618       return 0;
 619    }
 620
 621    assert(component < 4);
 622
 623    /* Treat RGB and SRGB as equivalent. */
 624    if (colorspace == UTIL_FORMAT_COLORSPACE_SRGB) {
 625       colorspace = UTIL_FORMAT_COLORSPACE_RGB;
 626    }
 627    if (desc->colorspace == UTIL_FORMAT_COLORSPACE_SRGB) {
 628       desc_colorspace = UTIL_FORMAT_COLORSPACE_RGB;
 629    } else {
 630       desc_colorspace = desc->colorspace;
 631    }
 632
 633    if (desc_colorspace != colorspace) {
 634       return 0;
 635    }
 636
 637    switch (desc->swizzle[component]) {
 638    case UTIL_FORMAT_SWIZZLE_X:
 639       return desc->channel[0].size;
 640    case UTIL_FORMAT_SWIZZLE_Y:
 641       return desc->channel[1].size;
 642    case UTIL_FORMAT_SWIZZLE_Z:
 643       return desc->channel[2].size;
 644    case UTIL_FORMAT_SWIZZLE_W:
 645       return desc->channel[3].size;
 646    default:
 647       return 0;
 648    }
 649 }
 650
 651 static INLINE boolean
 652 util_format_has_alpha(enum pipe_format format)
 653 {
 654    const struct util_format_description *desc = util_format_description(format);
 655
 656    assert(format);
 657    if (!format) {
 658       return FALSE;
 659    }
 660
 661    switch (desc->colorspace) {
 662    case UTIL_FORMAT_COLORSPACE_RGB:
 663    case UTIL_FORMAT_COLORSPACE_SRGB:
 664       return desc->swizzle[3] != UTIL_FORMAT_SWIZZLE_1;
 665    case UTIL_FORMAT_COLORSPACE_YUV:
 666       return FALSE;
 667    case UTIL_FORMAT_COLORSPACE_ZS:
 668       return FALSE;
 669    default:
 670       assert(0);
 671       return FALSE;
 672    }
 673 }
 674
 675 /**
 676  * Given a linear RGB colorspace format, return the corresponding SRGB
 677  * format, or PIPE_FORMAT_NONE if none.
 678  */
 679 static INLINE enum pipe_format
 680 util_format_srgb(enum pipe_format format)
 681 {
 682    switch (format) {
 683    case PIPE_FORMAT_L8_UNORM:
 684       return PIPE_FORMAT_L8_SRGB;
 685    case PIPE_FORMAT_L8A8_UNORM:
 686       return PIPE_FORMAT_L8A8_SRGB;
 687    case PIPE_FORMAT_R8G8B8_UNORM:
 688       return PIPE_FORMAT_R8G8B8_SRGB;
 689    case PIPE_FORMAT_A8B8G8R8_UNORM:
 690       return PIPE_FORMAT_A8B8G8R8_SRGB;
 691    case PIPE_FORMAT_X8B8G8R8_UNORM:
 692       return PIPE_FORMAT_X8B8G8R8_SRGB;
 693    case PIPE_FORMAT_B8G8R8A8_UNORM:
 694       return PIPE_FORMAT_B8G8R8A8_SRGB;
 695    case PIPE_FORMAT_B8G8R8X8_UNORM:
 696       return PIPE_FORMAT_B8G8R8X8_SRGB;
 697    case PIPE_FORMAT_A8R8G8B8_UNORM:
 698       return PIPE_FORMAT_A8R8G8B8_SRGB;
 699    case PIPE_FORMAT_X8R8G8B8_UNORM:
 700       return PIPE_FORMAT_X8R8G8B8_SRGB;
 701    case PIPE_FORMAT_DXT1_RGB:
 702       return PIPE_FORMAT_DXT1_SRGB;
 703    case PIPE_FORMAT_DXT1_RGBA:
 704       return PIPE_FORMAT_DXT1_SRGBA;
 705    case PIPE_FORMAT_DXT3_RGBA:
 706       return PIPE_FORMAT_DXT3_SRGBA;
 707    case PIPE_FORMAT_DXT5_RGBA:
 708       return PIPE_FORMAT_DXT5_SRGBA;
 709    default:
 710       return PIPE_FORMAT_NONE;
 711    }
 712 }
 713
 714 /**
 715  * Given an sRGB format, return the corresponding linear colorspace format.
 716  * For non sRGB formats, return the format unchanged.
 717  */
 718 static INLINE enum pipe_format
 719 util_format_linear(enum pipe_format format)
 720 {
 721    switch (format) {
 722    case PIPE_FORMAT_L8_SRGB:
 723       return PIPE_FORMAT_L8_UNORM;
 724    case PIPE_FORMAT_L8A8_SRGB:
 725       return PIPE_FORMAT_L8A8_UNORM;
 726    case PIPE_FORMAT_R8G8B8_SRGB:
 727       return PIPE_FORMAT_R8G8B8_UNORM;
 728    case PIPE_FORMAT_A8B8G8R8_SRGB:
 729       return PIPE_FORMAT_A8B8G8R8_UNORM;
 730    case PIPE_FORMAT_X8B8G8R8_SRGB:
 731       return PIPE_FORMAT_X8B8G8R8_UNORM;
 732    case PIPE_FORMAT_B8G8R8A8_SRGB:
 733       return PIPE_FORMAT_B8G8R8A8_UNORM;
 734    case PIPE_FORMAT_B8G8R8X8_SRGB:
 735       return PIPE_FORMAT_B8G8R8X8_UNORM;
 736    case PIPE_FORMAT_A8R8G8B8_SRGB:
 737       return PIPE_FORMAT_A8R8G8B8_UNORM;
 738    case PIPE_FORMAT_X8R8G8B8_SRGB:
 739       return PIPE_FORMAT_X8R8G8B8_UNORM;
 740    case PIPE_FORMAT_DXT1_SRGB:
 741       return PIPE_FORMAT_DXT1_RGB;
 742    case PIPE_FORMAT_DXT1_SRGBA:
 743       return PIPE_FORMAT_DXT1_RGBA;
 744    case PIPE_FORMAT_DXT3_SRGBA:
 745       return PIPE_FORMAT_DXT3_RGBA;
 746    case PIPE_FORMAT_DXT5_SRGBA:
 747       return PIPE_FORMAT_DXT5_RGBA;
 748    default:
 749       return format;
 750    }
 751 }
 752
 753 /**
 754  * Return the number of components stored.
 755  * Formats with block size != 1x1 will always have 1 component (the block).
 756  */
 757 static INLINE unsigned
 758 util_format_get_nr_components(enum pipe_format format)
 759 {
 760    const struct util_format_description *desc = util_format_description(format);
 761    return desc->nr_channels;
 762 }
 763
 764 /*
 765  * Format access functions.
 766  */
 767
 768 void
 769 util_format_read_4f(enum pipe_format format,
 770                     float *dst, unsigned dst_stride,
 771                     const void *src, unsigned src_stride,
 772                     unsigned x, unsigned y, unsigned w, unsigned h);
 773
 774 void
 775 util_format_write_4f(enum pipe_format format,
 776                      const float *src, unsigned src_stride,
 777                      void *dst, unsigned dst_stride,
 778                      unsigned x, unsigned y, unsigned w, unsigned h);
 779
 780 void
 781 util_format_read_4ub(enum pipe_format format,
 782                      uint8_t *dst, unsigned dst_stride,
 783                      const void *src, unsigned src_stride,
 784                      unsigned x, unsigned y, unsigned w, unsigned h);
 785
 786 void
 787 util_format_write_4ub(enum pipe_format format,
 788                       const uint8_t *src, unsigned src_stride,
 789                       void *dst, unsigned dst_stride,
 790                       unsigned x, unsigned y, unsigned w, unsigned h);
 791
 792 /*
 793  * Generic format conversion;
 794  */
 795
 796 boolean
 797 util_format_fits_8unorm(const struct util_format_description *format_desc);
 798
 799 void
 800 util_format_translate(enum pipe_format dst_format,
 801                       void *dst, unsigned dst_stride,
 802                       unsigned dst_x, unsigned dst_y,
 803                       enum pipe_format src_format,
 804                       const void *src, unsigned src_stride,
 805                       unsigned src_x, unsigned src_y,
 806                       unsigned width, unsigned height);
 807
 808 #ifdef __cplusplus
 809 } // extern "C" {
 810 #endif
 811
 812 #endif /* ! U_FORMAT_H */