u_format.h - Android社区 - https://www.androidos.net.cn/

/**************************************************************************
 *
 * Copyright 2009-2010 Vmware, Inc.
 * All Rights Reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sub license, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 *
 * The above copyright notice and this permission notice (including the
 * next paragraph) shall be included in all copies or substantial portions
 * of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
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#ifndef U_FORMAT_H
#define U_FORMAT_H

#include "pipe/p_format.h"
#include "pipe/p_defines.h"
#include "util/u_debug.h"

union pipe_color_union;

#ifdef __cplusplus
extern "C" {
#endif

/**
 * Describe how to pack/unpack pixels into/from the prescribed format.
 *
 * XXX: This could be renamed to something like util_format_pack, or broke down
 * in flags inside util_format_block that said exactly what we want.
 */
enum util_format_layout {
   /**
    * Formats with util_format_block::width == util_format_block::height == 1
    * that can be described as an ordinary data structure.
    */
   UTIL_FORMAT_LAYOUT_PLAIN = 0,

/**
    * Formats with sub-sampled channels.
    *
    * This is for formats like YVYU where there is less than one sample per
    * pixel.
    */
   UTIL_FORMAT_LAYOUT_SUBSAMPLED = 3,

/**
    * S3 Texture Compression formats.
    */
   UTIL_FORMAT_LAYOUT_S3TC = 4,

/**
    * Red-Green Texture Compression formats.
    */
   UTIL_FORMAT_LAYOUT_RGTC = 5,

/**
    * Ericsson Texture Compression
    */
   UTIL_FORMAT_LAYOUT_ETC = 6,

/**
    * BC6/7 Texture Compression
    */
   UTIL_FORMAT_LAYOUT_BPTC = 7,

/**
    * ASTC
    */
   UTIL_FORMAT_LAYOUT_ASTC = 8,

/**
    * Everything else that doesn't fit in any of the above layouts.
    */
   UTIL_FORMAT_LAYOUT_OTHER = 9
};

struct util_format_block
{
   /** Block width in pixels */
   unsigned width;
   
   /** Block height in pixels */
   unsigned height;

/** Block size in bits */
   unsigned bits;
};

enum util_format_type {
   UTIL_FORMAT_TYPE_VOID = 0,
   UTIL_FORMAT_TYPE_UNSIGNED = 1,
   UTIL_FORMAT_TYPE_SIGNED = 2,
   UTIL_FORMAT_TYPE_FIXED = 3,
   UTIL_FORMAT_TYPE_FLOAT = 4
};

enum util_format_colorspace {
   UTIL_FORMAT_COLORSPACE_RGB = 0,
   UTIL_FORMAT_COLORSPACE_SRGB = 1,
   UTIL_FORMAT_COLORSPACE_YUV = 2,
   UTIL_FORMAT_COLORSPACE_ZS = 3
};

struct util_format_channel_description
{
   unsigned type:5;        /**< UTIL_FORMAT_TYPE_x */
   unsigned normalized:1;
   unsigned pure_integer:1;
   unsigned size:9;        /**< bits per channel */
   unsigned shift:16;      /** number of bits from lsb */
};

struct util_format_description
{
   enum pipe_format format;

const char *name;

/**
    * Short name, striped of the prefix, lower case.
    */
   const char *short_name;

/**
    * Pixel block dimensions.
    */
   struct util_format_block block;

enum util_format_layout layout;

/**
    * The number of channels.
    */
   unsigned nr_channels:3;

/**
    * Whether all channels have the same number of (whole) bytes and type.
    */
   unsigned is_array:1;

/**
    * Whether the pixel format can be described as a bitfield structure.
    *
    * In particular:
    * - pixel depth must be 8, 16, or 32 bits;
    * - all channels must be unsigned, signed, or void
    */
   unsigned is_bitmask:1;

/**
    * Whether channels have mixed types (ignoring UTIL_FORMAT_TYPE_VOID).
    */
   unsigned is_mixed:1;

/**
    * Input channel description, in the order XYZW.
    *
    * Only valid for UTIL_FORMAT_LAYOUT_PLAIN formats.
    *
    * If each channel is accessed as an individual N-byte value, X is always
    * at the lowest address in memory, Y is always next, and so on.  For all
    * currently-defined formats, the N-byte value has native endianness.
    *
    * If instead a group of channels is accessed as a single N-byte value,
    * the order of the channels within that value depends on endianness.
    * For big-endian targets, X is the most significant subvalue,
    * otherwise it is the least significant one.
    *
    * For example, if X is 8 bits and Y is 24 bits, the memory order is:
    *
    *                 0  1  2  3
    *  little-endian: X  Yl Ym Yu    (l = lower, m = middle, u = upper)
    *  big-endian:    X  Yu Ym Yl
    *
    * If X is 5 bits, Y is 5 bits, Z is 5 bits and W is 1 bit, the layout is:
    *
    *                        0        1
    *                 msb  lsb msb  lsb
    *  little-endian: YYYXXXXX WZZZZZYY
    *  big-endian:    XXXXXYYY YYZZZZZW
    */
   struct util_format_channel_description channel[4];

/**
    * Output channel swizzle.
    *
    * The order is either:
    * - RGBA
    * - YUV(A)
    * - ZS
    * depending on the colorspace.
    */
   unsigned char swizzle[4];

/**
    * Colorspace transformation.
    */
   enum util_format_colorspace colorspace;

/**
    * Unpack pixel blocks to R8G8B8A8_UNORM.
    * Note: strides are in bytes.
    *
    * Only defined for non-depth-stencil formats.
    */
   void
   (*unpack_rgba_8unorm)(uint8_t *dst, unsigned dst_stride,
                         const uint8_t *src, unsigned src_stride,
                         unsigned width, unsigned height);

/**
    * Pack pixel blocks from R8G8B8A8_UNORM.
    * Note: strides are in bytes.
    *
    * Only defined for non-depth-stencil formats.
    */
   void
   (*pack_rgba_8unorm)(uint8_t *dst, unsigned dst_stride,
                       const uint8_t *src, unsigned src_stride,
                       unsigned width, unsigned height);

/**
    * Fetch a single pixel (i, j) from a block.
    *
    * XXX: Only defined for a very few select formats.
    */
   void
   (*fetch_rgba_8unorm)(uint8_t *dst,
                        const uint8_t *src,
                        unsigned i, unsigned j);

/**
    * Unpack pixel blocks to R32G32B32A32_FLOAT.
    * Note: strides are in bytes.
    *
    * Only defined for non-depth-stencil formats.
    */
   void
   (*unpack_rgba_float)(float *dst, unsigned dst_stride,
                        const uint8_t *src, unsigned src_stride,
                        unsigned width, unsigned height);

/**
    * Pack pixel blocks from R32G32B32A32_FLOAT.
    * Note: strides are in bytes.
    *
    * Only defined for non-depth-stencil formats.
    */
   void
   (*pack_rgba_float)(uint8_t *dst, unsigned dst_stride,
                      const float *src, unsigned src_stride,
                      unsigned width, unsigned height);

/**
    * Fetch a single pixel (i, j) from a block.
    *
    * Only defined for non-depth-stencil and non-integer formats.
    */
   void
   (*fetch_rgba_float)(float *dst,
                       const uint8_t *src,
                       unsigned i, unsigned j);

/**
    * Unpack pixels to Z32_UNORM.
    * Note: strides are in bytes.
    *
    * Only defined for depth formats.
    */
   void
   (*unpack_z_32unorm)(uint32_t *dst, unsigned dst_stride,
                       const uint8_t *src, unsigned src_stride,
                       unsigned width, unsigned height);

/**
    * Pack pixels from Z32_FLOAT.
    * Note: strides are in bytes.
    *
    * Only defined for depth formats.
    */
   void
   (*pack_z_32unorm)(uint8_t *dst, unsigned dst_stride,
                     const uint32_t *src, unsigned src_stride,
                     unsigned width, unsigned height);

/**
    * Unpack pixels to Z32_FLOAT.
    * Note: strides are in bytes.
    *
    * Only defined for depth formats.
    */
   void
   (*unpack_z_float)(float *dst, unsigned dst_stride,
                     const uint8_t *src, unsigned src_stride,
                     unsigned width, unsigned height);

/**
    * Pack pixels from Z32_FLOAT.
    * Note: strides are in bytes.
    *
    * Only defined for depth formats.
    */
   void
   (*pack_z_float)(uint8_t *dst, unsigned dst_stride,
                   const float *src, unsigned src_stride,
                   unsigned width, unsigned height);

/**
    * Unpack pixels to S8_UINT.
    * Note: strides are in bytes.
    *
    * Only defined for stencil formats.
    */
   void
   (*unpack_s_8uint)(uint8_t *dst, unsigned dst_stride,
                     const uint8_t *src, unsigned src_stride,
                     unsigned width, unsigned height);

/**
    * Pack pixels from S8_UINT.
    * Note: strides are in bytes.
    *
    * Only defined for stencil formats.
    */
   void
   (*pack_s_8uint)(uint8_t *dst, unsigned dst_stride,
                   const uint8_t *src, unsigned src_stride,
                   unsigned width, unsigned height);

/**
    * Unpack pixel blocks to R32G32B32A32_UINT.
    * Note: strides are in bytes.
    *
    * Only defined for INT formats.
    */
   void
   (*unpack_rgba_uint)(uint32_t *dst, unsigned dst_stride,
                       const uint8_t *src, unsigned src_stride,
                       unsigned width, unsigned height);

void
   (*pack_rgba_uint)(uint8_t *dst, unsigned dst_stride,
                     const uint32_t *src, unsigned src_stride,
                     unsigned width, unsigned height);

/**
    * Unpack pixel blocks to R32G32B32A32_SINT.
    * Note: strides are in bytes.
    *
    * Only defined for INT formats.
    */
   void
   (*unpack_rgba_sint)(int32_t *dst, unsigned dst_stride,
                       const uint8_t *src, unsigned src_stride,
                       unsigned width, unsigned height);

void
   (*pack_rgba_sint)(uint8_t *dst, unsigned dst_stride,
                     const int32_t *src, unsigned src_stride,
                     unsigned width, unsigned height);

/**
    * Fetch a single pixel (i, j) from a block.
    *
    * Only defined for unsigned (pure) integer formats.
    */
   void
   (*fetch_rgba_uint)(uint32_t *dst,
                      const uint8_t *src,
                      unsigned i, unsigned j);

/**
    * Fetch a single pixel (i, j) from a block.
    *
    * Only defined for signed (pure) integer formats.
    */
   void
   (*fetch_rgba_sint)(int32_t *dst,
                      const uint8_t *src,
                      unsigned i, unsigned j);
};

extern const struct util_format_description 
util_format_description_table[];

const struct util_format_description *
util_format_description(enum pipe_format format);

/*
 * Format query functions.
 */

static inline const char *
util_format_name(enum pipe_format format)
{
   const struct util_format_description *desc = util_format_description(format);

assert(desc);
   if (!desc) {
      return "PIPE_FORMAT_???";
   }

return desc->name;
}

static inline const char *
util_format_short_name(enum pipe_format format)
{
   const struct util_format_description *desc = util_format_description(format);

assert(desc);
   if (!desc) {
      return "???";
   }

return desc->short_name;
}

/**
 * Whether this format is plain, see UTIL_FORMAT_LAYOUT_PLAIN for more info.
 */
static inline boolean
util_format_is_plain(enum pipe_format format)
{
   const struct util_format_description *desc = util_format_description(format);

if (!format) {
      return FALSE;
   }

return desc->layout == UTIL_FORMAT_LAYOUT_PLAIN ? TRUE : FALSE;
}

static inline boolean 
util_format_is_compressed(enum pipe_format format)
{
   const struct util_format_description *desc = util_format_description(format);