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    UTIL_FORMAT_SWIZZLE_MAX = 7  /**< Number of enums counter (must be last) */
 110 };
 111
 112
 113 enum util_format_colorspace {
 114    UTIL_FORMAT_COLORSPACE_RGB = 0,
 115    UTIL_FORMAT_COLORSPACE_SRGB = 1,
 116    UTIL_FORMAT_COLORSPACE_YUV = 2,
 117    UTIL_FORMAT_COLORSPACE_ZS = 3
 118 };
 119
 120
 121 struct util_format_channel_description
 122 {
 123    unsigned type:5;        /**< UTIL_FORMAT_TYPE_x */
 124    unsigned normalized:1;
 125    unsigned pure_integer:1;
 126    unsigned size:9;        /**< bits per channel */
 127 };
 128
 129
 130 struct util_format_description
 131 {
 132    enum pipe_format format;
 133
 134    const char *name;
 135
 136    /**
 137     * Short name, striped of the prefix, lower case.
 138     */
 139    const char *short_name;
 140
 141    /**
 142     * Pixel block dimensions.
 143     */
 144    struct util_format_block block;
 145
 146    enum util_format_layout layout;
 147
 148    /**
 149     * The number of channels.
 150     */
 151    unsigned nr_channels:3;
 152
 153    /**
 154     * Whether all channels have the same number of (whole) bytes.
 155     */
 156    unsigned is_array:1;
 157
 158    /**
 159     * Whether the pixel format can be described as a bitfield structure.
 160     *
 161     * In particular:
 162     * - pixel depth must be 8, 16, or 32 bits;
 163     * - all channels must be unsigned, signed, or void
 164     */
 165    unsigned is_bitmask:1;
 166
 167    /**
 168     * Whether channels have mixed types (ignoring UTIL_FORMAT_TYPE_VOID).
 169     */
 170    unsigned is_mixed:1;
 171
 172    /**
 173     * Input channel description.
 174     *
 175     * Only valid for UTIL_FORMAT_LAYOUT_PLAIN formats.
 176     */
 177    struct util_format_channel_description channel[4];
 178
 179    /**
 180     * Output channel swizzle.
 181     *
 182     * The order is either:
 183     * - RGBA
 184     * - YUV(A)
 185     * - ZS
 186     * depending on the colorspace.
 187     */
 188    unsigned char swizzle[4];
 189
 190    /**
 191     * Colorspace transformation.
 192     */
 193    enum util_format_colorspace colorspace;
 194
 195    /**
 196     * Unpack pixel blocks to R8G8B8A8_UNORM.
 197     * Note: strides are in bytes.
 198     *
 199     * Only defined for non-depth-stencil formats.
 200     */
 201    void
 202    (*unpack_rgba_8unorm)(uint8_t *dst, unsigned dst_stride,
 203                          const uint8_t *src, unsigned src_stride,
 204                          unsigned width, unsigned height);
 205
 206    /**
 207     * Pack pixel blocks from R8G8B8A8_UNORM.
 208     * Note: strides are in bytes.
 209     *
 210     * Only defined for non-depth-stencil formats.
 211     */
 212    void
 213    (*pack_rgba_8unorm)(uint8_t *dst, unsigned dst_stride,
 214                        const uint8_t *src, unsigned src_stride,
 215                        unsigned width, unsigned height);
 216
 217    /**
 218     * Fetch a single pixel (i, j) from a block.
 219     *
 220     * XXX: Only defined for a very few select formats.
 221     */
 222    void
 223    (*fetch_rgba_8unorm)(uint8_t *dst,
 224                         const uint8_t *src,
 225                         unsigned i, unsigned j);
 226
 227    /**
 228     * Unpack pixel blocks to R32G32B32A32_FLOAT.
 229     * Note: strides are in bytes.
 230     *
 231     * Only defined for non-depth-stencil formats.
 232     */
 233    void
 234    (*unpack_rgba_float)(float *dst, unsigned dst_stride,
 235                         const uint8_t *src, unsigned src_stride,
 236                         unsigned width, unsigned height);
 237
 238    /**
 239     * Pack pixel blocks from R32G32B32A32_FLOAT.
 240     * Note: strides are in bytes.
 241     *
 242     * Only defined for non-depth-stencil formats.
 243     */
 244    void
 245    (*pack_rgba_float)(uint8_t *dst, unsigned dst_stride,
 246                       const float *src, unsigned src_stride,
 247                       unsigned width, unsigned height);
 248
 249    /**
 250     * Fetch a single pixel (i, j) from a block.
 251     *
 252     * Only defined for non-depth-stencil formats.
 253     */
 254    void
 255    (*fetch_rgba_float)(float *dst,
 256                        const uint8_t *src,
 257                        unsigned i, unsigned j);
 258
 259    /**
 260     * Unpack pixels to Z32_UNORM.
 261     * Note: strides are in bytes.
 262     *
 263     * Only defined for depth formats.
 264     */
 265    void
 266    (*unpack_z_32unorm)(uint32_t *dst, unsigned dst_stride,
 267                        const uint8_t *src, unsigned src_stride,
 268                        unsigned width, unsigned height);
 269
 270    /**
 271     * Pack pixels from Z32_FLOAT.
 272     * Note: strides are in bytes.
 273     *
 274     * Only defined for depth formats.
 275     */
 276    void
 277    (*pack_z_32unorm)(uint8_t *dst, unsigned dst_stride,
 278                      const uint32_t *src, unsigned src_stride,
 279                      unsigned width, unsigned height);
 280
 281    /**
 282     * Unpack pixels to Z32_FLOAT.
 283     * Note: strides are in bytes.
 284     *
 285     * Only defined for depth formats.
 286     */
 287    void
 288    (*unpack_z_float)(float *dst, unsigned dst_stride,
 289                      const uint8_t *src, unsigned src_stride,
 290                      unsigned width, unsigned height);
 291
 292    /**
 293     * Pack pixels from Z32_FLOAT.
 294     * Note: strides are in bytes.
 295     *
 296     * Only defined for depth formats.
 297     */
 298    void
 299    (*pack_z_float)(uint8_t *dst, unsigned dst_stride,
 300                    const float *src, unsigned src_stride,
 301                    unsigned width, unsigned height);
 302
 303    /**
 304     * Unpack pixels to S8_USCALED.
 305     * Note: strides are in bytes.
 306     *
 307     * Only defined for stencil formats.
 308     */
 309    void
 310    (*unpack_s_8uscaled)(uint8_t *dst, unsigned dst_stride,
 311                         const uint8_t *src, unsigned src_stride,
 312                         unsigned width, unsigned height);
 313
 314    /**
 315     * Pack pixels from S8_USCALED.
 316     * Note: strides are in bytes.
 317     *
 318     * Only defined for stencil formats.
 319     */
 320    void
 321    (*pack_s_8uscaled)(uint8_t *dst, unsigned dst_stride,
 322                       const uint8_t *src, unsigned src_stride,
 323                       unsigned width, unsigned height);
 324
 325   /**
 326     * Unpack pixel blocks to R32G32B32A32_UINT.
 327     * Note: strides are in bytes.
 328     *
 329     * Only defined for INT formats.
 330     */
 331    void
 332    (*unpack_rgba_uint)(unsigned *dst, unsigned dst_stride,
 333                        const uint8_t *src, unsigned src_stride,
 334                        unsigned width, unsigned height);
 335
 336    void
 337    (*pack_rgba_uint)(uint8_t *dst, unsigned dst_stride,
 338                      const unsigned *src, unsigned src_stride,
 339                      unsigned width, unsigned height);
 340
 341   /**
 342     * Unpack pixel blocks to R32G32B32A32_SINT.
 343     * Note: strides are in bytes.
 344     *
 345     * Only defined for INT formats.
 346     */
 347    void
 348    (*unpack_rgba_sint)(signed *dst, unsigned dst_stride,
 349                        const uint8_t *src, unsigned src_stride,
 350                        unsigned width, unsigned height);
 351
 352    void
 353    (*pack_rgba_sint)(uint8_t *dst, unsigned dst_stride,
 354                      const int *src, unsigned src_stride,
 355                      unsigned width, unsigned height);
 356 };
 357
 358
 359 extern const struct util_format_description
 360 util_format_description_table[];
 361
 362
 363 const struct util_format_description *
 364 util_format_description(enum pipe_format format);
 365
 366
 367 /*
 368  * Format query functions.
 369  */
 370
 371 static INLINE const char *
 372 util_format_name(enum pipe_format format)
 373 {
 374    const struct util_format_description *desc = util_format_description(format);
 375
 376    assert(desc);
 377    if (!desc) {
 378       return "PIPE_FORMAT_???";
 379    }
 380
 381    return desc->name;
 382 }
 383
 384 static INLINE const char *
 385 util_format_short_name(enum pipe_format format)
 386 {
 387    const struct util_format_description *desc = util_format_description(format);
 388
 389    assert(desc);
 390    if (!desc) {
 391       return "???";
 392    }
 393
 394    return desc->short_name;
 395 }
 396
 397 /**
 398  * Whether this format is plain, see UTIL_FORMAT_LAYOUT_PLAIN for more info.
 399  */
 400 static INLINE boolean
 401 util_format_is_plain(enum pipe_format format)
 402 {
 403    const struct util_format_description *desc = util_format_description(format);
 404
 405    if (!format) {
 406       return FALSE;
 407    }
 408
 409    return desc->layout == UTIL_FORMAT_LAYOUT_PLAIN ? TRUE : FALSE;
 410 }
 411
 412 static INLINE boolean
 413 util_format_is_compressed(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    switch (desc->layout) {
 423    case UTIL_FORMAT_LAYOUT_S3TC:
 424    case UTIL_FORMAT_LAYOUT_RGTC:
 425       /* XXX add other formats in the future */
 426       return TRUE;
 427    default:
 428       return FALSE;
 429    }
 430 }
 431
 432 static INLINE boolean
 433 util_format_is_s3tc(enum pipe_format format)
 434 {
 435    const struct util_format_description *desc = util_format_description(format);
 436
 437    assert(desc);
 438    if (!desc) {
 439       return FALSE;
 440    }
 441
 442    return desc->layout == UTIL_FORMAT_LAYOUT_S3TC ? TRUE : FALSE;
 443 }
 444
 445 static INLINE boolean
 446 util_format_is_srgb(enum pipe_format format)
 447 {
 448    const struct util_format_description *desc = util_format_description(format);
 449    return desc->colorspace == UTIL_FORMAT_COLORSPACE_SRGB;
 450 }
 451
 452 static INLINE boolean
 453 util_format_has_depth(const struct util_format_description *desc)
 454 {
 455    return desc->colorspace == UTIL_FORMAT_COLORSPACE_ZS &&
 456           desc->swizzle[0] != UTIL_FORMAT_SWIZZLE_NONE;
 457 }
 458
 459 static INLINE boolean
 460 util_format_has_stencil(const struct util_format_description *desc)
 461 {
 462    return desc->colorspace == UTIL_FORMAT_COLORSPACE_ZS &&
 463           desc->swizzle[1] != UTIL_FORMAT_SWIZZLE_NONE;
 464 }
 465
 466 static INLINE boolean
 467 util_format_is_depth_or_stencil(enum pipe_format format)
 468 {
 469    const struct util_format_description *desc = util_format_description(format);
 470
 471    assert(desc);
 472    if (!desc) {
 473       return FALSE;
 474    }
 475
 476    return util_format_has_depth(desc) ||
 477           util_format_has_stencil(desc);
 478 }
 479
 480 static INLINE boolean
 481 util_format_is_depth_and_stencil(enum pipe_format format)
 482 {
 483    const struct util_format_description *desc = util_format_description(format);
 484
 485    assert(desc);
 486    if (!desc) {
 487       return FALSE;
 488    }
 489
 490    return util_format_has_depth(desc) &&
 491           util_format_has_stencil(desc);
 492 }
 493
 494
 495 /**
 496  * Give the RGBA colormask of the channels that can be represented in this
 497  * format.
 498  *
 499  * That is, the channels whose values are preserved.
 500  */
 501 static INLINE unsigned
 502 util_format_colormask(const struct util_format_description *desc)
 503 {
 504    unsigned colormask;
 505    unsigned chan;
 506
 507    switch (desc->colorspace) {
 508    case UTIL_FORMAT_COLORSPACE_RGB:
 509    case UTIL_FORMAT_COLORSPACE_SRGB:
 510    case UTIL_FORMAT_COLORSPACE_YUV:
 511       colormask = 0;
 512       for (chan = 0; chan < 4; ++chan) {
 513          if (desc->swizzle[chan] < 4) {
 514             colormask |= (1 << chan);
 515          }
 516       }
 517       return colormask;
 518    case UTIL_FORMAT_COLORSPACE_ZS:
 519       return 0;
 520    default:
 521       assert(0);
 522       return 0;
 523    }
 524 }
 525
 526
 527 boolean
 528 util_format_is_float(enum pipe_format format);
 529
 530
 531 boolean
 532 util_format_is_rgb_no_alpha(enum pipe_format format);
 533
 534
 535 boolean
 536 util_format_is_luminance(enum pipe_format format);
 537
 538
 539 boolean
 540 util_format_is_luminance_alpha(enum pipe_format format);
 541
 542
 543 boolean
 544 util_format_is_intensity(enum pipe_format format);
 545
 546 boolean
 547 util_format_is_pure_integer(enum pipe_format format);
 548
 549 boolean
 550 util_format_is_pure_sint(enum pipe_format format);
 551
 552 boolean
 553 util_format_is_pure_uint(enum pipe_format format);
 554
 555 /**
 556  * Whether the src format can be blitted to destation format with a simple
 557  * memcpy.
 558  */
 559 boolean
 560 util_is_format_compatible(const struct util_format_description *src_desc,
 561                           const struct util_format_description *dst_desc);
 562
 563 /**
 564  * Whether the format is supported by Gallium for the given bindings.
 565  * This covers S3TC textures and floating-point render targets.
 566  */
 567 boolean
 568 util_format_is_supported(enum pipe_format format, unsigned bind);
 569
 570 /**
 571  * Whether this format is a rgab8 variant.
 572  *
 573  * That is, any format that matches the
 574  *
 575  *   PIPE_FORMAT_?8?8?8?8_UNORM
 576  */
 577 static INLINE boolean
 578 util_format_is_rgba8_variant(const struct util_format_description *desc)
 579 {
 580    unsigned chan;
 581
 582    if(desc->block.width != 1 ||
 583       desc->block.height != 1 ||
 584       desc->block.bits != 32)
 585       return FALSE;
 586
 587    for(chan = 0; chan < 4; ++chan) {
 588       if(desc->channel[chan].type != UTIL_FORMAT_TYPE_UNSIGNED &&
 589          desc->channel[chan].type != UTIL_FORMAT_TYPE_VOID)
 590          return FALSE;
 591       if(desc->channel[chan].size != 8)
 592          return FALSE;
 593    }
 594
 595    return TRUE;
 596 }
 597
 598
 599 /**
 600  * Return total bits needed for the pixel format per block.
 601  */
 602 static INLINE uint
 603 util_format_get_blocksizebits(enum pipe_format format)
 604 {
 605    const struct util_format_description *desc = util_format_description(format);
 606
 607    assert(desc);
 608    if (!desc) {
 609       return 0;
 610    }
 611
 612    return desc->block.bits;
 613 }
 614
 615 /**
 616  * Return bytes per block (not pixel) for the given format.
 617  */
 618 static INLINE uint
 619 util_format_get_blocksize(enum pipe_format format)
 620 {
 621    uint bits = util_format_get_blocksizebits(format);
 622
 623    assert(bits % 8 == 0);
 624
 625    return bits / 8;
 626 }
 627
 628 static INLINE uint
 629 util_format_get_blockwidth(enum pipe_format format)
 630 {
 631    const struct util_format_description *desc = util_format_description(format);
 632
 633    assert(desc);
 634    if (!desc) {
 635       return 1;
 636    }
 637
 638    return desc->block.width;
 639 }
 640
 641 static INLINE uint
 642 util_format_get_blockheight(enum pipe_format format)
 643 {
 644    const struct util_format_description *desc = util_format_description(format);
 645
 646    assert(desc);
 647    if (!desc) {
 648       return 1;
 649    }
 650
 651    return desc->block.height;
 652 }
 653
 654 static INLINE unsigned
 655 util_format_get_nblocksx(enum pipe_format format,
 656                          unsigned x)
 657 {
 658    unsigned blockwidth = util_format_get_blockwidth(format);
 659    return (x + blockwidth - 1) / blockwidth;
 660 }
 661
 662 static INLINE unsigned
 663 util_format_get_nblocksy(enum pipe_format format,
 664                          unsigned y)
 665 {
 666    unsigned blockheight = util_format_get_blockheight(format);
 667    return (y + blockheight - 1) / blockheight;
 668 }
 669
 670 static INLINE unsigned
 671 util_format_get_nblocks(enum pipe_format format,
 672                         unsigned width,
 673                         unsigned height)
 674 {
 675    return util_format_get_nblocksx(format, width) * util_format_get_nblocksy(format, height);
 676 }
 677
 678 static INLINE size_t
 679 util_format_get_stride(enum pipe_format format,
 680                        unsigned width)
 681 {
 682    return util_format_get_nblocksx(format, width) * util_format_get_blocksize(format);
 683 }
 684
 685 static INLINE size_t
 686 util_format_get_2d_size(enum pipe_format format,
 687                         size_t stride,
 688                         unsigned height)
 689 {
 690    return util_format_get_nblocksy(format, height) * stride;
 691 }
 692
 693 static INLINE uint
 694 util_format_get_component_bits(enum pipe_format format,
 695                                enum util_format_colorspace colorspace,
 696                                uint component)
 697 {
 698    const struct util_format_description *desc = util_format_description(format);
 699    enum util_format_colorspace desc_colorspace;
 700
 701    assert(format);
 702    if (!format) {
 703       return 0;
 704    }
 705
 706    assert(component < 4);
 707
 708    /* Treat RGB and SRGB as equivalent. */
 709    if (colorspace == UTIL_FORMAT_COLORSPACE_SRGB) {
 710       colorspace = UTIL_FORMAT_COLORSPACE_RGB;
 711    }
 712    if (desc->colorspace == UTIL_FORMAT_COLORSPACE_SRGB) {
 713       desc_colorspace = UTIL_FORMAT_COLORSPACE_RGB;
 714    } else {
 715       desc_colorspace = desc->colorspace;
 716    }
 717
 718    if (desc_colorspace != colorspace) {
 719       return 0;
 720    }
 721
 722    switch (desc->swizzle[component]) {
 723    case UTIL_FORMAT_SWIZZLE_X:
 724       return desc->channel[0].size;
 725    case UTIL_FORMAT_SWIZZLE_Y:
 726       return desc->channel[1].size;
 727    case UTIL_FORMAT_SWIZZLE_Z:
 728       return desc->channel[2].size;
 729    case UTIL_FORMAT_SWIZZLE_W:
 730       return desc->channel[3].size;
 731    default:
 732       return 0;
 733    }
 734 }
 735
 736 static INLINE boolean
 737 util_format_has_alpha(enum pipe_format format)
 738 {
 739    const struct util_format_description *desc = util_format_description(format);
 740
 741    assert(format);
 742    if (!format) {
 743       return FALSE;
 744    }
 745
 746    switch (desc->colorspace) {
 747    case UTIL_FORMAT_COLORSPACE_RGB:
 748    case UTIL_FORMAT_COLORSPACE_SRGB:
 749       return desc->swizzle[3] != UTIL_FORMAT_SWIZZLE_1;
 750    case UTIL_FORMAT_COLORSPACE_YUV:
 751       return FALSE;
 752    case UTIL_FORMAT_COLORSPACE_ZS:
 753       return FALSE;
 754    default:
 755       assert(0);
 756       return FALSE;
 757    }
 758 }
 759
 760 /**
 761  * Given a linear RGB colorspace format, return the corresponding SRGB
 762  * format, or PIPE_FORMAT_NONE if none.
 763  */
 764 static INLINE enum pipe_format
 765 util_format_srgb(enum pipe_format format)
 766 {
 767    switch (format) {
 768    case PIPE_FORMAT_L8_UNORM:
 769       return PIPE_FORMAT_L8_SRGB;
 770    case PIPE_FORMAT_L8A8_UNORM:
 771       return PIPE_FORMAT_L8A8_SRGB;
 772    case PIPE_FORMAT_R8G8B8_UNORM:
 773       return PIPE_FORMAT_R8G8B8_SRGB;
 774    case PIPE_FORMAT_A8B8G8R8_UNORM:
 775       return PIPE_FORMAT_A8B8G8R8_SRGB;
 776    case PIPE_FORMAT_X8B8G8R8_UNORM:
 777       return PIPE_FORMAT_X8B8G8R8_SRGB;
 778    case PIPE_FORMAT_B8G8R8A8_UNORM:
 779       return PIPE_FORMAT_B8G8R8A8_SRGB;
 780    case PIPE_FORMAT_B8G8R8X8_UNORM:
 781       return PIPE_FORMAT_B8G8R8X8_SRGB;
 782    case PIPE_FORMAT_A8R8G8B8_UNORM:
 783       return PIPE_FORMAT_A8R8G8B8_SRGB;
 784    case PIPE_FORMAT_X8R8G8B8_UNORM:
 785       return PIPE_FORMAT_X8R8G8B8_SRGB;
 786    case PIPE_FORMAT_DXT1_RGB:
 787       return PIPE_FORMAT_DXT1_SRGB;
 788    case PIPE_FORMAT_DXT1_RGBA:
 789       return PIPE_FORMAT_DXT1_SRGBA;
 790    case PIPE_FORMAT_DXT3_RGBA:
 791       return PIPE_FORMAT_DXT3_SRGBA;
 792    case PIPE_FORMAT_DXT5_RGBA:
 793       return PIPE_FORMAT_DXT5_SRGBA;
 794    default:
 795       return PIPE_FORMAT_NONE;
 796    }
 797 }
 798
 799 /**
 800  * Given an sRGB format, return the corresponding linear colorspace format.
 801  * For non sRGB formats, return the format unchanged.
 802  */
 803 static INLINE enum pipe_format
 804 util_format_linear(enum pipe_format format)
 805 {
 806    switch (format) {
 807    case PIPE_FORMAT_L8_SRGB:
 808       return PIPE_FORMAT_L8_UNORM;
 809    case PIPE_FORMAT_L8A8_SRGB:
 810       return PIPE_FORMAT_L8A8_UNORM;
 811    case PIPE_FORMAT_R8G8B8_SRGB:
 812       return PIPE_FORMAT_R8G8B8_UNORM;
 813    case PIPE_FORMAT_A8B8G8R8_SRGB:
 814       return PIPE_FORMAT_A8B8G8R8_UNORM;
 815    case PIPE_FORMAT_X8B8G8R8_SRGB:
 816       return PIPE_FORMAT_X8B8G8R8_UNORM;
 817    case PIPE_FORMAT_B8G8R8A8_SRGB:
 818       return PIPE_FORMAT_B8G8R8A8_UNORM;
 819    case PIPE_FORMAT_B8G8R8X8_SRGB:
 820       return PIPE_FORMAT_B8G8R8X8_UNORM;
 821    case PIPE_FORMAT_A8R8G8B8_SRGB:
 822       return PIPE_FORMAT_A8R8G8B8_UNORM;
 823    case PIPE_FORMAT_X8R8G8B8_SRGB:
 824       return PIPE_FORMAT_X8R8G8B8_UNORM;
 825    case PIPE_FORMAT_DXT1_SRGB:
 826       return PIPE_FORMAT_DXT1_RGB;
 827    case PIPE_FORMAT_DXT1_SRGBA:
 828       return PIPE_FORMAT_DXT1_RGBA;
 829    case PIPE_FORMAT_DXT3_SRGBA:
 830       return PIPE_FORMAT_DXT3_RGBA;
 831    case PIPE_FORMAT_DXT5_SRGBA:
 832       return PIPE_FORMAT_DXT5_RGBA;
 833    default:
 834       return format;
 835    }
 836 }
 837
 838 /**
 839  * Return the number of components stored.
 840  * Formats with block size != 1x1 will always have 1 component (the block).
 841  */
 842 static INLINE unsigned
 843 util_format_get_nr_components(enum pipe_format format)
 844 {
 845    const struct util_format_description *desc = util_format_description(format);
 846    return desc->nr_channels;
 847 }
 848
 849 /**
 850  * Return the index of the first non-void channel
 851  * -1 if no non-void channels
 852  */
 853 static INLINE int
 854 util_format_get_first_non_void_channel(enum pipe_format format)
 855 {
 856    const struct util_format_description *desc = util_format_description(format);
 857    int i;
 858
 859    for (i = 0; i < 4; i++)
 860       if (desc->channel[i].type != UTIL_FORMAT_TYPE_VOID)
 861          break;
 862
 863    if (i == 4)
 864        return -1;
 865
 866    return i;
 867 }
 868
 869 /*
 870  * Format access functions.
 871  */
 872
 873 void
 874 util_format_read_4f(enum pipe_format format,
 875                     float *dst, unsigned dst_stride,
 876                     const void *src, unsigned src_stride,
 877                     unsigned x, unsigned y, unsigned w, unsigned h);
 878
 879 void
 880 util_format_write_4f(enum pipe_format format,
 881                      const float *src, unsigned src_stride,
 882                      void *dst, unsigned dst_stride,
 883                      unsigned x, unsigned y, unsigned w, unsigned h);
 884
 885 void
 886 util_format_read_4ub(enum pipe_format format,
 887                      uint8_t *dst, unsigned dst_stride,
 888                      const void *src, unsigned src_stride,
 889                      unsigned x, unsigned y, unsigned w, unsigned h);
 890
 891 void
 892 util_format_write_4ub(enum pipe_format format,
 893                       const uint8_t *src, unsigned src_stride,
 894                       void *dst, unsigned dst_stride,
 895                       unsigned x, unsigned y, unsigned w, unsigned h);
 896
 897 void
 898 util_format_read_4ui(enum pipe_format format,
 899                      unsigned *dst, unsigned dst_stride,
 900                      const void *src, unsigned src_stride,
 901                      unsigned x, unsigned y, unsigned w, unsigned h);
 902
 903 void
 904 util_format_write_4ui(enum pipe_format format,
 905                       const unsigned int *src, unsigned src_stride,
 906                       void *dst, unsigned dst_stride,
 907                       unsigned x, unsigned y, unsigned w, unsigned h);
 908
 909 void
 910 util_format_read_4i(enum pipe_format format,
 911                     int *dst, unsigned dst_stride,
 912                     const void *src, unsigned src_stride,
 913                     unsigned x, unsigned y, unsigned w, unsigned h);
 914
 915 void
 916 util_format_write_4i(enum pipe_format format,
 917                      const int *src, unsigned src_stride,
 918                      void *dst, unsigned dst_stride,
 919                      unsigned x, unsigned y, unsigned w, unsigned h);
 920
 921 /*
 922  * Generic format conversion;
 923  */
 924
 925 boolean
 926 util_format_fits_8unorm(const struct util_format_description *format_desc);
 927
 928 void
 929 util_format_translate(enum pipe_format dst_format,
 930                       void *dst, unsigned dst_stride,
 931                       unsigned dst_x, unsigned dst_y,
 932                       enum pipe_format src_format,
 933                       const void *src, unsigned src_stride,
 934                       unsigned src_x, unsigned src_y,
 935                       unsigned width, unsigned height);
 936
 937 /*
 938  * Swizzle operations.
 939  */
 940
 941 /* Compose two sets of swizzles.
 942  * If V is a 4D vector and the function parameters represent functions that
 943  * swizzle vector components, this holds:
 944  *     swz2(swz1(V)) = dst(V)
 945  */
 946 void util_format_compose_swizzles(const unsigned char swz1[4],
 947                                   const unsigned char swz2[4],
 948                                   unsigned char dst[4]);
 949
 950 void util_format_swizzle_4f(float *dst, const float *src,
 951                             const unsigned char swz[4]);
 952
 953 void util_format_unswizzle_4f(float *dst, const float *src,
 954                               const unsigned char swz[4]);
 955
 956 #ifdef __cplusplus
 957 } // extern "C" {
 958 #endif
 959
 960 #endif /* ! U_FORMAT_H */