layers/vk_layer_utils.h

/**************************************************************************
 *
 * Copyright 2015 Valve Software
 * 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, sublicense, 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 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 NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 *
 * Author: Mark Lobodzinski <mark@lunarg.com>
 * Author: Courtney Goeltzenleuchter <courtney@LunarG.com>
 **************************************************************************/
#pragma once
#include <stdbool.h>
#ifndef WIN32
#include <strings.h> /* for ffs() */
#else
#include <intrin.h> /* for __lzcnt() */
#endif

#ifdef __cplusplus
extern "C" {
#endif

typedef enum VkFormatCompatibilityClass {
    VK_FORMAT_COMPATIBILITY_CLASS_NONE_BIT          = 0,
    VK_FORMAT_COMPATIBILITY_CLASS_8_BIT             = 1,
    VK_FORMAT_COMPATIBILITY_CLASS_16_BIT            = 2,
    VK_FORMAT_COMPATIBILITY_CLASS_24_BIT            = 3,
    VK_FORMAT_COMPATIBILITY_CLASS_32_BIT            = 4,
    VK_FORMAT_COMPATIBILITY_CLASS_48_BIT            = 5,
    VK_FORMAT_COMPATIBILITY_CLASS_64_BIT            = 6,
    VK_FORMAT_COMPATIBILITY_CLASS_96_BIT            = 7,
    VK_FORMAT_COMPATIBILITY_CLASS_128_BIT           = 8,
    VK_FORMAT_COMPATIBILITY_CLASS_192_BIT           = 9,
    VK_FORMAT_COMPATIBILITY_CLASS_256_BIT           = 10,
    VK_FORMAT_COMPATIBILITY_CLASS_BC1_RGB_BIT       = 11,
    VK_FORMAT_COMPATIBILITY_CLASS_BC1_RGBA_BIT      = 12,
    VK_FORMAT_COMPATIBILITY_CLASS_BC2_BIT           = 13,
    VK_FORMAT_COMPATIBILITY_CLASS_BC3_BIT           = 14,
    VK_FORMAT_COMPATIBILITY_CLASS_BC4_BIT           = 15,
    VK_FORMAT_COMPATIBILITY_CLASS_BC5_BIT           = 16,
    VK_FORMAT_COMPATIBILITY_CLASS_BC6H_BIT          = 17,
    VK_FORMAT_COMPATIBILITY_CLASS_BC7_BIT           = 18,
    VK_FORMAT_COMPATIBILITY_CLASS_ETC2_RGB_BIT      = 19,
    VK_FORMAT_COMPATIBILITY_CLASS_ETC2_RGBA_BIT     = 20,
    VK_FORMAT_COMPATIBILITY_CLASS_ETC2_EAC_RGBA_BIT = 21,
    VK_FORMAT_COMPATIBILITY_CLASS_EAC_R_BIT         = 22,
    VK_FORMAT_COMPATIBILITY_CLASS_EAC_RG_BIT        = 23,
    VK_FORMAT_COMPATIBILITY_CLASS_ASTC_4X4_BIT      = 24,
    VK_FORMAT_COMPATIBILITY_CLASS_ASTC_5X4_BIT      = 25,
    VK_FORMAT_COMPATIBILITY_CLASS_ASTC_5X5_BIT      = 26,
    VK_FORMAT_COMPATIBILITY_CLASS_ASTC_6X5_BIT      = 27,
    VK_FORMAT_COMPATIBILITY_CLASS_ASTC_6X6_BIT      = 28,
    VK_FORMAT_COMPATIBILITY_CLASS_ASTC_8X5_BIT      = 29,
    VK_FORMAT_COMPATIBILITY_CLASS_ASTC_8X6_BIT      = 20,
    VK_FORMAT_COMPATIBILITY_CLASS_ASTC_8X8_BIT      = 31,
    VK_FORMAT_COMPATIBILITY_CLASS_ASTC_10X5_BIT     = 32,
    VK_FORMAT_COMPATIBILITY_CLASS_ASTC_10X6_BIT     = 33,
    VK_FORMAT_COMPATIBILITY_CLASS_ASTC_10X8_BIT     = 34,
    VK_FORMAT_COMPATIBILITY_CLASS_ASTC_10X10_BIT    = 35,
    VK_FORMAT_COMPATIBILITY_CLASS_ASTC_12X10_BIT    = 36,
    VK_FORMAT_COMPATIBILITY_CLASS_ASTC_12X12_BIT    = 37,
    VK_FORMAT_COMPATIBILITY_CLASS_D16_BIT           = 38,
    VK_FORMAT_COMPATIBILITY_CLASS_D24_BIT           = 39,
    VK_FORMAT_COMPATIBILITY_CLASS_D32_BIT           = 30,
    VK_FORMAT_COMPATIBILITY_CLASS_S8_BIT            = 41,
    VK_FORMAT_COMPATIBILITY_CLASS_D16S8_BIT         = 42,
    VK_FORMAT_COMPATIBILITY_CLASS_D24S8_BIT         = 43,
    VK_FORMAT_COMPATIBILITY_CLASS_D32S8_BIT         = 44,
    VK_FORMAT_COMPATIBILITY_CLASS_MAX_ENUM          = 45
} VkFormatCompatibilityClass;


static inline bool vk_format_is_undef(VkFormat format)
{
    return (format == VK_FORMAT_UNDEFINED);
}

bool vk_format_is_depth_or_stencil(VkFormat format);
bool vk_format_is_depth_and_stencil(VkFormat format);
bool vk_format_is_depth_only(VkFormat format);
bool vk_format_is_stencil_only(VkFormat format);

static inline bool vk_format_is_color(VkFormat format)
{
    return !(vk_format_is_undef(format) || vk_format_is_depth_or_stencil(format));
}

bool                       vk_format_is_norm(VkFormat format);
bool                       vk_format_is_int(VkFormat format);
bool                       vk_format_is_sint(VkFormat format);
bool                       vk_format_is_uint(VkFormat format);
bool                       vk_format_is_float(VkFormat format);
bool                       vk_format_is_srgb(VkFormat format);
bool                       vk_format_is_compressed(VkFormat format);
size_t                     vk_format_get_size(VkFormat format);
unsigned int               vk_format_get_channel_count(VkFormat format);
VkFormatCompatibilityClass vk_format_get_compatibility_class(VkFormat format);

static inline int u_ffs(int val)
{
#ifdef WIN32
    unsigned long bit_pos = 0;
    if (_BitScanForward(&bit_pos, val) != 0) {
        bit_pos += 1;
    }
    return bit_pos;
#else
    return ffs(val);
#endif
}

#ifdef __cplusplus
}
#endif