src/gallium/auxiliary/util/u_format.h

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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:6;        /**< UTIL_FORMAT_TYPE_x */
 124    unsigned normalized:1;
 125    unsigned size:9;        /**< bits per channel */
 126 };
 127
 128
 129 struct util_format_description
 130 {
 131    enum pipe_format format;
 132
 133    const char *name;
 134
 135    /**
 136     * Short name, striped of the prefix, lower case.
 137     */
 138    const char *short_name;
 139
 140    /**
 141     * Pixel block dimensions.
 142     */
 143    struct util_format_block block;
 144
 145    enum util_format_layout layout;
 146
 147    /**
 148     * The number of channels.
 149     */
 150    unsigned nr_channels:3;
 151
 152    /**
 153     * Whether all channels have the same number of (whole) bytes.
 154     */
 155    unsigned is_array:1;
 156
 157    /**
 158     * Whether the pixel format can be described as a bitfield structure.
 159     *
 160     * In particular:
 161     * - pixel depth must be 8, 16, or 32 bits;
 162     * - all channels must be unsigned, signed, or void
 163     */
 164    unsigned is_bitmask:1;
 165
 166    /**
 167     * Whether channels have mixed types (ignoring UTIL_FORMAT_TYPE_VOID).
 168     */
 169    unsigned is_mixed:1;
 170
 171    /**
 172     * Input channel description.
 173     *
 174     * Only valid for UTIL_FORMAT_LAYOUT_PLAIN formats.
 175     */
 176    struct util_format_channel_description channel[4];
 177
 178    /**
 179     * Output channel swizzle.
 180     *
 181     * The order is either:
 182     * - RGBA
 183     * - YUV(A)
 184     * - ZS
 185     * depending on the colorspace.
 186     */
 187    unsigned char swizzle[4];
 188
 189    /**
 190     * Colorspace transformation.
 191     */
 192    enum util_format_colorspace colorspace;
 193
 194    /**
 195     * Unpack pixel blocks to R8G8B8A8_UNORM.
 196     * Note: strides are in bytes.
 197     *
 198     * Only defined for non-depth-stencil formats.
 199     */
 200    void
 201    (*unpack_rgba_8unorm)(uint8_t *dst, unsigned dst_stride,
 202                          const uint8_t *src, unsigned src_stride,
 203                          unsigned width, unsigned height);
 204
 205    /**
 206     * Pack pixel blocks from R8G8B8A8_UNORM.
 207     * Note: strides are in bytes.
 208     *
 209     * Only defined for non-depth-stencil formats.
 210     */
 211    void
 212    (*pack_rgba_8unorm)(uint8_t *dst, unsigned dst_stride,
 213                        const uint8_t *src, unsigned src_stride,
 214                        unsigned width, unsigned height);
 215
 216    /**
 217     * Fetch a single pixel (i, j) from a block.
 218     *
 219     * XXX: Only defined for a very few select formats.
 220     */
 221    void
 222    (*fetch_rgba_8unorm)(uint8_t *dst,
 223                         const uint8_t *src,
 224                         unsigned i, unsigned j);
 225
 226    /**
 227     * Unpack pixel blocks to R32G32B32A32_FLOAT.
 228     * Note: strides are in bytes.
 229     *
 230     * Only defined for non-depth-stencil formats.
 231     */
 232    void
 233    (*unpack_rgba_float)(float *dst, unsigned dst_stride,
 234                         const uint8_t *src, unsigned src_stride,
 235                         unsigned width, unsigned height);
 236
 237    /**
 238     * Pack pixel blocks from R32G32B32A32_FLOAT.
 239     * Note: strides are in bytes.
 240     *
 241     * Only defined for non-depth-stencil formats.
 242     */
 243    void
 244    (*pack_rgba_float)(uint8_t *dst, unsigned dst_stride,
 245                       const float *src, unsigned src_stride,
 246                       unsigned width, unsigned height);
 247
 248    /**
 249     * Fetch a single pixel (i, j) from a block.
 250     *
 251     * Only defined for non-depth-stencil formats.
 252     */
 253    void
 254    (*fetch_rgba_float)(float *dst,
 255                        const uint8_t *src,
 256                        unsigned i, unsigned j);
 257
 258    /**
 259     * Unpack pixels to Z32_UNORM.
 260     * Note: strides are in bytes.
 261     *
 262     * Only defined for depth formats.
 263     */
 264    void
 265    (*unpack_z_32unorm)(uint32_t *dst, unsigned dst_stride,
 266                        const uint8_t *src, unsigned src_stride,
 267                        unsigned width, unsigned height);
 268
 269    /**
 270     * Pack pixels from Z32_FLOAT.
 271     * Note: strides are in bytes.
 272     *
 273     * Only defined for depth formats.
 274     */
 275    void
 276    (*pack_z_32unorm)(uint8_t *dst, unsigned dst_stride,
 277                      const uint32_t *src, unsigned src_stride,
 278                      unsigned width, unsigned height);
 279
 280    /**
 281     * Unpack pixels to Z32_FLOAT.
 282     * Note: strides are in bytes.
 283     *
 284     * Only defined for depth formats.
 285     */
 286    void
 287    (*unpack_z_float)(float *dst, unsigned dst_stride,
 288                      const uint8_t *src, unsigned src_stride,
 289                      unsigned width, unsigned height);
 290
 291    /**
 292     * Pack pixels from Z32_FLOAT.
 293     * Note: strides are in bytes.
 294     *
 295     * Only defined for depth formats.
 296     */
 297    void
 298    (*pack_z_float)(uint8_t *dst, unsigned dst_stride,
 299                    const float *src, unsigned src_stride,
 300                    unsigned width, unsigned height);
 301
 302    /**
 303     * Unpack pixels to S8_USCALED.
 304     * Note: strides are in bytes.
 305     *
 306     * Only defined for stencil formats.
 307     */
 308    void
 309    (*unpack_s_8uscaled)(uint8_t *dst, unsigned dst_stride,
 310                         const uint8_t *src, unsigned src_stride,
 311                         unsigned width, unsigned height);
 312
 313    /**
 314     * Pack pixels from S8_USCALED.
 315     * Note: strides are in bytes.
 316     *
 317     * Only defined for stencil formats.
 318     */
 319    void
 320    (*pack_s_8uscaled)(uint8_t *dst, unsigned dst_stride,
 321                       const uint8_t *src, unsigned src_stride,
 322                       unsigned width, unsigned height);
 323
 324 };
 325
 326
 327 extern const struct util_format_description
 328 util_format_description_table[];
 329
 330
 331 const struct util_format_description *
 332 util_format_description(enum pipe_format format);
 333
 334
 335 /*
 336  * Format query functions.
 337  */
 338
 339 static INLINE const char *
 340 util_format_name(enum pipe_format format)
 341 {
 342    const struct util_format_description *desc = util_format_description(format);
 343
 344    assert(desc);
 345    if (!desc) {
 346       return "PIPE_FORMAT_???";
 347    }
 348
 349    return desc->name;
 350 }
 351
 352 static INLINE const char *
 353 util_format_short_name(enum pipe_format format)
 354 {
 355    const struct util_format_description *desc = util_format_description(format);
 356
 357    assert(desc);
 358    if (!desc) {
 359       return "???";
 360    }
 361
 362    return desc->short_name;
 363 }
 364
 365 /**
 366  * Whether this format is plain, see UTIL_FORMAT_LAYOUT_PLAIN for more info.
 367  */
 368 static INLINE boolean
 369 util_format_is_plain(enum pipe_format format)
 370 {
 371    const struct util_format_description *desc = util_format_description(format);
 372
 373    if (!format) {
 374       return FALSE;
 375    }
 376
 377    return desc->layout == UTIL_FORMAT_LAYOUT_PLAIN ? TRUE : FALSE;
 378 }
 379
 380 static INLINE boolean
 381 util_format_is_compressed(enum pipe_format format)
 382 {
 383    const struct util_format_description *desc = util_format_description(format);
 384
 385    assert(desc);
 386    if (!desc) {
 387       return FALSE;
 388    }
 389
 390    switch (desc->layout) {
 391    case UTIL_FORMAT_LAYOUT_S3TC:
 392    case UTIL_FORMAT_LAYOUT_RGTC:
 393       /* XXX add other formats in the future */
 394       return TRUE;
 395    default:
 396       return FALSE;
 397    }
 398 }
 399
 400 static INLINE boolean
 401 util_format_is_s3tc(enum pipe_format format)
 402 {
 403    const struct util_format_description *desc = util_format_description(format);
 404
 405    assert(desc);
 406    if (!desc) {
 407       return FALSE;
 408    }
 409
 410    return desc->layout == UTIL_FORMAT_LAYOUT_S3TC ? TRUE : FALSE;
 411 }
 412
 413 static INLINE boolean
 414 util_format_is_depth_or_stencil(enum pipe_format format)
 415 {
 416    const struct util_format_description *desc = util_format_description(format);
 417
 418    assert(desc);
 419    if (!desc) {
 420       return FALSE;
 421    }
 422
 423    return desc->colorspace == UTIL_FORMAT_COLORSPACE_ZS ? TRUE : FALSE;
 424 }
 425
 426 static INLINE boolean
 427 util_format_is_depth_and_stencil(enum pipe_format format)
 428 {
 429    const struct util_format_description *desc = util_format_description(format);
 430
 431    assert(desc);
 432    if (!desc) {
 433       return FALSE;
 434    }
 435
 436    if (desc->colorspace != UTIL_FORMAT_COLORSPACE_ZS) {
 437       return FALSE;
 438    }
 439
 440    return (desc->swizzle[0] != UTIL_FORMAT_SWIZZLE_NONE &&
 441            desc->swizzle[1] != UTIL_FORMAT_SWIZZLE_NONE) ? TRUE : FALSE;
 442 }
 443
 444
 445 /**
 446  * Give the RGBA colormask of the channels that can be represented in this
 447  * format.
 448  *
 449  * That is, the channels whose values are preserved.
 450  */
 451 static INLINE unsigned
 452 util_format_colormask(const struct util_format_description *desc)
 453 {
 454    unsigned colormask;
 455    unsigned chan;
 456
 457    switch (desc->colorspace) {
 458    case UTIL_FORMAT_COLORSPACE_RGB:
 459    case UTIL_FORMAT_COLORSPACE_SRGB:
 460    case UTIL_FORMAT_COLORSPACE_YUV:
 461       colormask = 0;
 462       for (chan = 0; chan < 4; ++chan) {
 463          if (desc->swizzle[chan] < 4) {
 464             colormask |= (1 << chan);
 465          }
 466       }
 467       return colormask;
 468    case UTIL_FORMAT_COLORSPACE_ZS:
 469       return 0;
 470    default:
 471       assert(0);
 472       return 0;
 473    }
 474 }
 475
 476
 477 boolean
 478 util_format_is_float(enum pipe_format format);
 479
 480
 481 boolean
 482 util_format_is_rgb_no_alpha(enum pipe_format format);
 483
 484
 485 boolean
 486 util_format_is_luminance(enum pipe_format format);
 487
 488
 489 boolean
 490 util_format_is_luminance_alpha(enum pipe_format format);
 491
 492
 493 boolean
 494 util_format_is_intensity(enum pipe_format format);
 495
 496
 497 /**
 498  * Whether the src format can be blitted to destation format with a simple
 499  * memcpy.
 500  */
 501 boolean
 502 util_is_format_compatible(const struct util_format_description *src_desc,
 503                           const struct util_format_description *dst_desc);
 504
 505 /**
 506  * Whether the format is supported by Gallium for the given bindings.
 507  * This covers S3TC textures and floating-point render targets.
 508  */
 509 boolean
 510 util_format_is_supported(enum pipe_format format, unsigned bind);
 511
 512 /**
 513  * Whether this format is a rgab8 variant.
 514  *
 515  * That is, any format that matches the
 516  *
 517  *   PIPE_FORMAT_?8?8?8?8_UNORM
 518  */
 519 static INLINE boolean
 520 util_format_is_rgba8_variant(const struct util_format_description *desc)
 521 {
 522    unsigned chan;
 523
 524    if(desc->block.width != 1 ||
 525       desc->block.height != 1 ||
 526       desc->block.bits != 32)
 527       return FALSE;
 528
 529    for(chan = 0; chan < 4; ++chan) {
 530       if(desc->channel[chan].type != UTIL_FORMAT_TYPE_UNSIGNED &&
 531          desc->channel[chan].type != UTIL_FORMAT_TYPE_VOID)
 532          return FALSE;
 533       if(desc->channel[chan].size != 8)
 534          return FALSE;
 535    }
 536
 537    return TRUE;
 538 }
 539
 540
 541 /**
 542  * Return total bits needed for the pixel format per block.
 543  */
 544 static INLINE uint
 545 util_format_get_blocksizebits(enum pipe_format format)
 546 {
 547    const struct util_format_description *desc = util_format_description(format);
 548
 549    assert(desc);
 550    if (!desc) {
 551       return 0;
 552    }
 553
 554    return desc->block.bits;
 555 }
 556
 557 /**
 558  * Return bytes per block (not pixel) for the given format.
 559  */
 560 static INLINE uint
 561 util_format_get_blocksize(enum pipe_format format)
 562 {
 563    uint bits = util_format_get_blocksizebits(format);
 564
 565    assert(bits % 8 == 0);
 566
 567    return bits / 8;
 568 }
 569
 570 static INLINE uint
 571 util_format_get_blockwidth(enum pipe_format format)
 572 {
 573    const struct util_format_description *desc = util_format_description(format);
 574
 575    assert(desc);
 576    if (!desc) {
 577       return 1;
 578    }
 579
 580    return desc->block.width;
 581 }
 582
 583 static INLINE uint
 584 util_format_get_blockheight(enum pipe_format format)
 585 {
 586    const struct util_format_description *desc = util_format_description(format);
 587
 588    assert(desc);
 589    if (!desc) {
 590       return 1;
 591    }
 592
 593    return desc->block.height;
 594 }
 595
 596 static INLINE unsigned
 597 util_format_get_nblocksx(enum pipe_format format,
 598                          unsigned x)
 599 {
 600    unsigned blockwidth = util_format_get_blockwidth(format);
 601    return (x + blockwidth - 1) / blockwidth;
 602 }
 603
 604 static INLINE unsigned
 605 util_format_get_nblocksy(enum pipe_format format,
 606                          unsigned y)
 607 {
 608    unsigned blockheight = util_format_get_blockheight(format);
 609    return (y + blockheight - 1) / blockheight;
 610 }
 611
 612 static INLINE unsigned
 613 util_format_get_nblocks(enum pipe_format format,
 614                         unsigned width,
 615                         unsigned height)
 616 {
 617    return util_format_get_nblocksx(format, width) * util_format_get_nblocksy(format, height);
 618 }
 619
 620 static INLINE size_t
 621 util_format_get_stride(enum pipe_format format,
 622                        unsigned width)
 623 {
 624    return util_format_get_nblocksx(format, width) * util_format_get_blocksize(format);
 625 }
 626
 627 static INLINE size_t
 628 util_format_get_2d_size(enum pipe_format format,
 629                         size_t stride,
 630                         unsigned height)
 631 {
 632    return util_format_get_nblocksy(format, height) * stride;
 633 }
 634
 635 static INLINE uint
 636 util_format_get_component_bits(enum pipe_format format,
 637                                enum util_format_colorspace colorspace,
 638                                uint component)
 639 {
 640    const struct util_format_description *desc = util_format_description(format);
 641    enum util_format_colorspace desc_colorspace;
 642
 643    assert(format);
 644    if (!format) {
 645       return 0;
 646    }
 647
 648    assert(component < 4);
 649
 650    /* Treat RGB and SRGB as equivalent. */
 651    if (colorspace == UTIL_FORMAT_COLORSPACE_SRGB) {
 652       colorspace = UTIL_FORMAT_COLORSPACE_RGB;
 653    }
 654    if (desc->colorspace == UTIL_FORMAT_COLORSPACE_SRGB) {
 655       desc_colorspace = UTIL_FORMAT_COLORSPACE_RGB;
 656    } else {
 657       desc_colorspace = desc->colorspace;
 658    }
 659
 660    if (desc_colorspace != colorspace) {
 661       return 0;
 662    }
 663
 664    switch (desc->swizzle[component]) {
 665    case UTIL_FORMAT_SWIZZLE_X:
 666       return desc->channel[0].size;
 667    case UTIL_FORMAT_SWIZZLE_Y:
 668       return desc->channel[1].size;
 669    case UTIL_FORMAT_SWIZZLE_Z:
 670       return desc->channel[2].size;
 671    case UTIL_FORMAT_SWIZZLE_W:
 672       return desc->channel[3].size;
 673    default:
 674       return 0;
 675    }
 676 }
 677
 678 static INLINE boolean
 679 util_format_has_alpha(enum pipe_format format)
 680 {
 681    const struct util_format_description *desc = util_format_description(format);
 682
 683    assert(format);
 684    if (!format) {
 685       return FALSE;
 686    }
 687
 688    switch (desc->colorspace) {
 689    case UTIL_FORMAT_COLORSPACE_RGB:
 690    case UTIL_FORMAT_COLORSPACE_SRGB:
 691       return desc->swizzle[3] != UTIL_FORMAT_SWIZZLE_1;
 692    case UTIL_FORMAT_COLORSPACE_YUV:
 693       return FALSE;
 694    case UTIL_FORMAT_COLORSPACE_ZS:
 695       return FALSE;
 696    default:
 697       assert(0);
 698       return FALSE;
 699    }
 700 }
 701
 702 /**
 703  * Given a linear RGB colorspace format, return the corresponding SRGB
 704  * format, or PIPE_FORMAT_NONE if none.
 705  */
 706 static INLINE enum pipe_format
 707 util_format_srgb(enum pipe_format format)
 708 {
 709    switch (format) {
 710    case PIPE_FORMAT_L8_UNORM:
 711       return PIPE_FORMAT_L8_SRGB;
 712    case PIPE_FORMAT_L8A8_UNORM:
 713       return PIPE_FORMAT_L8A8_SRGB;
 714    case PIPE_FORMAT_R8G8B8_UNORM:
 715       return PIPE_FORMAT_R8G8B8_SRGB;
 716    case PIPE_FORMAT_A8B8G8R8_UNORM:
 717       return PIPE_FORMAT_A8B8G8R8_SRGB;
 718    case PIPE_FORMAT_X8B8G8R8_UNORM:
 719       return PIPE_FORMAT_X8B8G8R8_SRGB;
 720    case PIPE_FORMAT_B8G8R8A8_UNORM:
 721       return PIPE_FORMAT_B8G8R8A8_SRGB;
 722    case PIPE_FORMAT_B8G8R8X8_UNORM:
 723       return PIPE_FORMAT_B8G8R8X8_SRGB;
 724    case PIPE_FORMAT_A8R8G8B8_UNORM:
 725       return PIPE_FORMAT_A8R8G8B8_SRGB;
 726    case PIPE_FORMAT_X8R8G8B8_UNORM:
 727       return PIPE_FORMAT_X8R8G8B8_SRGB;
 728    case PIPE_FORMAT_DXT1_RGB:
 729       return PIPE_FORMAT_DXT1_SRGB;
 730    case PIPE_FORMAT_DXT1_RGBA:
 731       return PIPE_FORMAT_DXT1_SRGBA;
 732    case PIPE_FORMAT_DXT3_RGBA:
 733       return PIPE_FORMAT_DXT3_SRGBA;
 734    case PIPE_FORMAT_DXT5_RGBA:
 735       return PIPE_FORMAT_DXT5_SRGBA;
 736    default:
 737       return PIPE_FORMAT_NONE;
 738    }
 739 }
 740
 741 /**
 742  * Given an sRGB format, return the corresponding linear colorspace format.
 743  * For non sRGB formats, return the format unchanged.
 744  */
 745 static INLINE enum pipe_format
 746 util_format_linear(enum pipe_format format)
 747 {
 748    switch (format) {
 749    case PIPE_FORMAT_L8_SRGB:
 750       return PIPE_FORMAT_L8_UNORM;
 751    case PIPE_FORMAT_L8A8_SRGB:
 752       return PIPE_FORMAT_L8A8_UNORM;
 753    case PIPE_FORMAT_R8G8B8_SRGB:
 754       return PIPE_FORMAT_R8G8B8_UNORM;
 755    case PIPE_FORMAT_A8B8G8R8_SRGB:
 756       return PIPE_FORMAT_A8B8G8R8_UNORM;
 757    case PIPE_FORMAT_X8B8G8R8_SRGB:
 758       return PIPE_FORMAT_X8B8G8R8_UNORM;
 759    case PIPE_FORMAT_B8G8R8A8_SRGB:
 760       return PIPE_FORMAT_B8G8R8A8_UNORM;
 761    case PIPE_FORMAT_B8G8R8X8_SRGB:
 762       return PIPE_FORMAT_B8G8R8X8_UNORM;
 763    case PIPE_FORMAT_A8R8G8B8_SRGB:
 764       return PIPE_FORMAT_A8R8G8B8_UNORM;
 765    case PIPE_FORMAT_X8R8G8B8_SRGB:
 766       return PIPE_FORMAT_X8R8G8B8_UNORM;
 767    case PIPE_FORMAT_DXT1_SRGB:
 768       return PIPE_FORMAT_DXT1_RGB;
 769    case PIPE_FORMAT_DXT1_SRGBA:
 770       return PIPE_FORMAT_DXT1_RGBA;
 771    case PIPE_FORMAT_DXT3_SRGBA:
 772       return PIPE_FORMAT_DXT3_RGBA;
 773    case PIPE_FORMAT_DXT5_SRGBA:
 774       return PIPE_FORMAT_DXT5_RGBA;
 775    default:
 776       return format;
 777    }
 778 }
 779
 780 /**
 781  * Return the number of components stored.
 782  * Formats with block size != 1x1 will always have 1 component (the block).
 783  */
 784 static INLINE unsigned
 785 util_format_get_nr_components(enum pipe_format format)
 786 {
 787    const struct util_format_description *desc = util_format_description(format);
 788    return desc->nr_channels;
 789 }
 790
 791 /*
 792  * Format access functions.
 793  */
 794
 795 void
 796 util_format_read_4f(enum pipe_format format,
 797                     float *dst, unsigned dst_stride,
 798                     const void *src, unsigned src_stride,
 799                     unsigned x, unsigned y, unsigned w, unsigned h);
 800
 801 void
 802 util_format_write_4f(enum pipe_format format,
 803                      const float *src, unsigned src_stride,
 804                      void *dst, unsigned dst_stride,
 805                      unsigned x, unsigned y, unsigned w, unsigned h);
 806
 807 void
 808 util_format_read_4ub(enum pipe_format format,
 809                      uint8_t *dst, unsigned dst_stride,
 810                      const void *src, unsigned src_stride,
 811                      unsigned x, unsigned y, unsigned w, unsigned h);
 812
 813 void
 814 util_format_write_4ub(enum pipe_format format,
 815                       const uint8_t *src, unsigned src_stride,
 816                       void *dst, unsigned dst_stride,
 817                       unsigned x, unsigned y, unsigned w, unsigned h);
 818
 819 /*
 820  * Generic format conversion;
 821  */
 822
 823 boolean
 824 util_format_fits_8unorm(const struct util_format_description *format_desc);
 825
 826 void
 827 util_format_translate(enum pipe_format dst_format,
 828                       void *dst, unsigned dst_stride,
 829                       unsigned dst_x, unsigned dst_y,
 830                       enum pipe_format src_format,
 831                       const void *src, unsigned src_stride,
 832                       unsigned src_x, unsigned src_y,
 833                       unsigned width, unsigned height);
 834
 835 /*
 836  * Swizzle operations.
 837  */
 838
 839 /* Compose two sets of swizzles.
 840  * If V is a 4D vector and the function parameters represent functions that
 841  * swizzle vector components, this holds:
 842  *     swz2(swz1(V)) = dst(V)
 843  */
 844 void util_format_compose_swizzles(const unsigned char swz1[4],
 845                                   const unsigned char swz2[4],
 846                                   unsigned char dst[4]);
 847
 848 void util_format_swizzle_4f(float *dst, const float *src,
 849                             const unsigned char swz[4]);
 850
 851 void util_format_unswizzle_4f(float *dst, const float *src,
 852                               const unsigned char swz[4]);
 853
 854 #ifdef __cplusplus
 855 } // extern "C" {
 856 #endif
 857
 858 #endif /* ! U_FORMAT_H */