//-------------------------------------------------------------------------------------
// DirectXTex.inl
//  
// DirectX Texture Library
//
// THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF
// ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO
// THE IMPLIED WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A
// PARTICULAR PURPOSE.
//
// Copyright (c) Microsoft Corporation. All rights reserved.
//
// http://go.microsoft.com/fwlink/?LinkId=248926
//-------------------------------------------------------------------------------------

#if defined(_MSC_VER) && (_MSC_VER > 1000)
#pragma once
#endif

//=====================================================================================
// DXGI Format Utilities
//=====================================================================================

inline bool IsValid( DXGI_FORMAT fmt )
{
#ifdef DXGI_1_2_FORMATS
    return ( static_cast<size_t>(fmt) >= 1 && static_cast<size_t>(fmt) <= 115 );
#else
    return ( static_cast<size_t>(fmt) >= 1 && static_cast<size_t>(fmt) <= 99 );
#endif
}

inline bool IsCompressed( DXGI_FORMAT fmt )
{
    switch ( fmt )
    {
    case DXGI_FORMAT_BC1_TYPELESS:
    case DXGI_FORMAT_BC1_UNORM:
    case DXGI_FORMAT_BC1_UNORM_SRGB:
    case DXGI_FORMAT_BC2_TYPELESS:
    case DXGI_FORMAT_BC2_UNORM:
    case DXGI_FORMAT_BC2_UNORM_SRGB:
    case DXGI_FORMAT_BC3_TYPELESS:
    case DXGI_FORMAT_BC3_UNORM:
    case DXGI_FORMAT_BC3_UNORM_SRGB:
    case DXGI_FORMAT_BC4_TYPELESS:
    case DXGI_FORMAT_BC4_UNORM:
    case DXGI_FORMAT_BC4_SNORM:
    case DXGI_FORMAT_BC5_TYPELESS:
    case DXGI_FORMAT_BC5_UNORM:
    case DXGI_FORMAT_BC5_SNORM:
    case DXGI_FORMAT_BC6H_TYPELESS:
    case DXGI_FORMAT_BC6H_UF16:
    case DXGI_FORMAT_BC6H_SF16:
    case DXGI_FORMAT_BC7_TYPELESS:
    case DXGI_FORMAT_BC7_UNORM:
    case DXGI_FORMAT_BC7_UNORM_SRGB:
        return true;

    default:
        return false;
    }
}

inline bool IsPacked( DXGI_FORMAT fmt )
{
    return ( (fmt == DXGI_FORMAT_R8G8_B8G8_UNORM) || (fmt == DXGI_FORMAT_G8R8_G8B8_UNORM) );
}

inline bool IsVideo( DXGI_FORMAT fmt )
{
#ifdef DXGI_1_2_FORMATS
    switch ( fmt )
    {
    case DXGI_FORMAT_AYUV:
    case DXGI_FORMAT_Y410:
    case DXGI_FORMAT_Y416:
    case DXGI_FORMAT_NV12:
    case DXGI_FORMAT_P010:
    case DXGI_FORMAT_P016:
    case DXGI_FORMAT_YUY2:
    case DXGI_FORMAT_Y210:
    case DXGI_FORMAT_Y216:
    case DXGI_FORMAT_NV11:
        // These video formats can be used with the 3D pipeline through special view mappings
        return true;

    case DXGI_FORMAT_420_OPAQUE:
    case DXGI_FORMAT_AI44:
    case DXGI_FORMAT_IA44:
    case DXGI_FORMAT_P8:
    case DXGI_FORMAT_A8P8:
        // These are limited use video formats not usable in any way by the 3D pipeline
        return true;

    default:
        return false;
    }
#else // !DXGI_1_2_FORMATS
    UNREFERENCED_PARAMETER(fmt);
    return false;
#endif
}

inline bool IsSRGB( DXGI_FORMAT fmt )
{
    switch( fmt )
    {
    case DXGI_FORMAT_R8G8B8A8_UNORM_SRGB:
    case DXGI_FORMAT_BC1_UNORM_SRGB:
    case DXGI_FORMAT_BC2_UNORM_SRGB:
    case DXGI_FORMAT_BC3_UNORM_SRGB:
    case DXGI_FORMAT_B8G8R8A8_UNORM_SRGB:
    case DXGI_FORMAT_B8G8R8X8_UNORM_SRGB:
    case DXGI_FORMAT_BC7_UNORM_SRGB:
        return true;

    default:
        return false;
    }
}

inline bool IsTypeless( DXGI_FORMAT fmt )
{
    switch( fmt )
    {
    case DXGI_FORMAT_R32G32B32A32_TYPELESS:
    case DXGI_FORMAT_R32G32B32_TYPELESS:
    case DXGI_FORMAT_R16G16B16A16_TYPELESS:
    case DXGI_FORMAT_R32G32_TYPELESS:
    case DXGI_FORMAT_R32G8X24_TYPELESS:
    case DXGI_FORMAT_R32_FLOAT_X8X24_TYPELESS:
    case DXGI_FORMAT_X32_TYPELESS_G8X24_UINT:
    case DXGI_FORMAT_R10G10B10A2_TYPELESS:
    case DXGI_FORMAT_R8G8B8A8_TYPELESS:
    case DXGI_FORMAT_R16G16_TYPELESS:
    case DXGI_FORMAT_R32_TYPELESS:
    case DXGI_FORMAT_R24G8_TYPELESS:
    case DXGI_FORMAT_R24_UNORM_X8_TYPELESS:
    case DXGI_FORMAT_X24_TYPELESS_G8_UINT:
    case DXGI_FORMAT_R8G8_TYPELESS:
    case DXGI_FORMAT_R16_TYPELESS:
    case DXGI_FORMAT_R8_TYPELESS:
    case DXGI_FORMAT_BC1_TYPELESS:
    case DXGI_FORMAT_BC2_TYPELESS:
    case DXGI_FORMAT_BC3_TYPELESS:
    case DXGI_FORMAT_BC4_TYPELESS:
    case DXGI_FORMAT_BC5_TYPELESS:
    case DXGI_FORMAT_B8G8R8A8_TYPELESS:
    case DXGI_FORMAT_B8G8R8X8_TYPELESS:
    case DXGI_FORMAT_BC6H_TYPELESS:
    case DXGI_FORMAT_BC7_TYPELESS:
        return true;

    default:
        return false;
    }
}

inline size_t ComputeScanlines( _In_ DXGI_FORMAT fmt, _In_ size_t height )
{
    switch ( fmt )
    {
    case DXGI_FORMAT_BC1_TYPELESS:
    case DXGI_FORMAT_BC1_UNORM:
    case DXGI_FORMAT_BC1_UNORM_SRGB:
    case DXGI_FORMAT_BC2_TYPELESS:
    case DXGI_FORMAT_BC2_UNORM:
    case DXGI_FORMAT_BC2_UNORM_SRGB:
    case DXGI_FORMAT_BC3_TYPELESS:
    case DXGI_FORMAT_BC3_UNORM:
    case DXGI_FORMAT_BC3_UNORM_SRGB:
    case DXGI_FORMAT_BC4_TYPELESS:
    case DXGI_FORMAT_BC4_UNORM:
    case DXGI_FORMAT_BC4_SNORM:
    case DXGI_FORMAT_BC5_TYPELESS:
    case DXGI_FORMAT_BC5_UNORM:
    case DXGI_FORMAT_BC5_SNORM:
    case DXGI_FORMAT_BC6H_TYPELESS:
    case DXGI_FORMAT_BC6H_UF16:
    case DXGI_FORMAT_BC6H_SF16:
    case DXGI_FORMAT_BC7_TYPELESS:
    case DXGI_FORMAT_BC7_UNORM:
    case DXGI_FORMAT_BC7_UNORM_SRGB:
        return std::max<size_t>( 1, (height + 3) / 4 );

    default:
        return height;
    }
}

//=====================================================================================
// Image I/O
//=====================================================================================
inline HRESULT SaveToDDSMemory( const Image& image, DWORD flags, Blob& blob )
{
    TexMetadata mdata;
    memset( &mdata, 0, sizeof(mdata) );
    mdata.width = image.width;
    mdata.height = image.height;
    mdata.depth = 1;
    mdata.arraySize = 1;
    mdata.mipLevels = 1;
    mdata.format = image.format;
    mdata.dimension = TEX_DIMENSION_TEXTURE2D;

    return SaveToDDSMemory( &image, 1, mdata, flags, blob );
}

inline HRESULT SaveToDDSFile( const Image& image, DWORD flags, LPCWSTR szFile )
{
    TexMetadata mdata;
    memset( &mdata, 0, sizeof(mdata) );
    mdata.width = image.width;
    mdata.height = image.height;
    mdata.depth = 1;
    mdata.arraySize = 1;
    mdata.mipLevels = 1;
    mdata.format = image.format;
    mdata.dimension = TEX_DIMENSION_TEXTURE2D;

    return SaveToDDSFile( &image, 1, mdata, flags, szFile );
}