godot/thirdparty/libktx/lib/ktxint.h

267 lines
7.1 KiB
C++

/* -*- tab-width: 4; -*- */
/* vi: set sw=2 ts=4 expandtab: */
/* $Id: e36ad79b5eac8ea237d6a05602c71aadab575519 $ */
/*
* Copyright 2010-2020 The Khronos Group Inc.
* SPDX-License-Identifier: Apache-2.0
*/
/*
* Author: Mark Callow from original code by Georg Kolling
*/
#ifndef KTXINT_H
#define KTXINT_H
#include <math.h>
/* Define this to include the ETC unpack software in the library. */
#ifndef SUPPORT_SOFTWARE_ETC_UNPACK
/* Include for all GL versions because have seen OpenGL ES 3
* implementaions that do not support ETC1 (ARM Mali emulator v1.0)!
*/
#define SUPPORT_SOFTWARE_ETC_UNPACK 1
#endif
#ifndef MAX
#define MAX(x, y) (((x) > (y)) ? (x) : (y))
#endif
#define QUOTE(x) #x
#define STR(x) QUOTE(x)
#define KTX2_IDENTIFIER_REF { 0xAB, 0x4B, 0x54, 0x58, 0x20, 0x32, 0x30, 0xBB, 0x0D, 0x0A, 0x1A, 0x0A }
#define KTX2_HEADER_SIZE (80)
#ifdef __cplusplus
extern "C" {
#endif
/**
* @internal
* @brief used to pass GL context capabilites to subroutines.
*/
#define _KTX_NO_R16_FORMATS 0x0
#define _KTX_R16_FORMATS_NORM 0x1
#define _KTX_R16_FORMATS_SNORM 0x2
#define _KTX_ALL_R16_FORMATS (_KTX_R16_FORMATS_NORM | _KTX_R16_FORMATS_SNORM)
extern GLint _ktxR16Formats;
extern GLboolean _ktxSupportsSRGB;
/**
* @internal
* @~English
* @brief KTX file header.
*
* See the KTX specification for descriptions.
*/
typedef struct KTX_header {
ktx_uint8_t identifier[12];
ktx_uint32_t endianness;
ktx_uint32_t glType;
ktx_uint32_t glTypeSize;
ktx_uint32_t glFormat;
ktx_uint32_t glInternalformat;
ktx_uint32_t glBaseInternalformat;
ktx_uint32_t pixelWidth;
ktx_uint32_t pixelHeight;
ktx_uint32_t pixelDepth;
ktx_uint32_t numberOfArrayElements;
ktx_uint32_t numberOfFaces;
ktx_uint32_t numberOfMipLevels;
ktx_uint32_t bytesOfKeyValueData;
} KTX_header;
/* This will cause compilation to fail if the struct size doesn't match */
typedef int KTX_header_SIZE_ASSERT [sizeof(KTX_header) == KTX_HEADER_SIZE];
/**
* @internal
* @~English
* @brief 32-bit KTX 2 index entry.
*/
typedef struct ktxIndexEntry32 {
ktx_uint32_t byteOffset; /*!< Offset of item from start of file. */
ktx_uint32_t byteLength; /*!< Number of bytes of data in the item. */
} ktxIndexEntry32;
/**
* @internal
* @~English
* @brief 64-bit KTX 2 index entry.
*/
typedef struct ktxIndexEntry64 {
ktx_uint64_t byteOffset; /*!< Offset of item from start of file. */
ktx_uint64_t byteLength; /*!< Number of bytes of data in the item. */
} ktxIndexEntry64;
/**
* @internal
* @~English
* @brief KTX 2 file header.
*
* See the KTX 2 specification for descriptions.
*/
typedef struct KTX_header2 {
ktx_uint8_t identifier[12];
ktx_uint32_t vkFormat;
ktx_uint32_t typeSize;
ktx_uint32_t pixelWidth;
ktx_uint32_t pixelHeight;
ktx_uint32_t pixelDepth;
ktx_uint32_t layerCount;
ktx_uint32_t faceCount;
ktx_uint32_t levelCount;
ktx_uint32_t supercompressionScheme;
ktxIndexEntry32 dataFormatDescriptor;
ktxIndexEntry32 keyValueData;
ktxIndexEntry64 supercompressionGlobalData;
} KTX_header2;
/* This will cause compilation to fail if the struct size doesn't match */
typedef int KTX_header2_SIZE_ASSERT [sizeof(KTX_header2) == KTX2_HEADER_SIZE];
/**
* @internal
* @~English
* @brief KTX 2 level index entry.
*/
typedef struct ktxLevelIndexEntry {
ktx_uint64_t byteOffset; /*!< Offset of level from start of file. */
ktx_uint64_t byteLength;
/*!< Number of bytes of compressed image data in the level. */
ktx_uint64_t uncompressedByteLength;
/*!< Number of bytes of uncompressed image data in the level. */
} ktxLevelIndexEntry;
/**
* @internal
* @~English
* @brief Structure for supplemental information about the texture.
*
* _ktxCheckHeader returns supplemental information about the texture in this
* structure that is derived during checking of the file header.
*/
typedef struct KTX_supplemental_info
{
ktx_uint8_t compressed;
ktx_uint8_t generateMipmaps;
ktx_uint16_t textureDimension;
} KTX_supplemental_info;
/**
* @internal
* @var ktx_uint8_t KTX_supplemental_info::compressed
* @~English
* @brief KTX_TRUE, if this a compressed texture, KTX_FALSE otherwise?
*/
/**
* @internal
* @var ktx_uint8_t KTX_supplemental_info::generateMipmaps
* @~English
* @brief KTX_TRUE, if mipmap generation is required, KTX_FALSE otherwise.
*/
/**
* @internal
* @var ktx_uint16_t KTX_supplemental_info::textureDimension
* @~English
* @brief The number of dimensions, 1, 2 or 3, of data in the texture image.
*/
/*
* @internal
* CheckHeader1
*
* Reads the KTX file header and performs some sanity checking on the values
*/
KTX_error_code ktxCheckHeader1_(KTX_header* pHeader,
KTX_supplemental_info* pSuppInfo);
/*
* @internal
* CheckHeader2
*
* Reads the KTX 2 file header and performs some sanity checking on the values
*/
KTX_error_code ktxCheckHeader2_(KTX_header2* pHeader,
KTX_supplemental_info* pSuppInfo);
/*
* SwapEndian16: Swaps endianness in an array of 16-bit values
*/
void _ktxSwapEndian16(ktx_uint16_t* pData16, ktx_size_t count);
/*
* SwapEndian32: Swaps endianness in an array of 32-bit values
*/
void _ktxSwapEndian32(ktx_uint32_t* pData32, ktx_size_t count);
/*
* SwapEndian32: Swaps endianness in an array of 64-bit values
*/
void _ktxSwapEndian64(ktx_uint64_t* pData64, ktx_size_t count);
/*
* UnpackETC: uncompresses an ETC compressed texture image
*/
KTX_error_code _ktxUnpackETC(const GLubyte* srcETC, const GLenum srcFormat,
ktx_uint32_t active_width, ktx_uint32_t active_height,
GLubyte** dstImage,
GLenum* format, GLenum* internalFormat, GLenum* type,
GLint R16Formats, GLboolean supportsSRGB);
/*
* Pad nbytes to next multiple of n
*/
#define _KTX_PADN(n, nbytes) (ktx_uint32_t)(n * ceilf((float)(nbytes) / n))
/*
* Calculate bytes of of padding needed to reach next multiple of n.
*/
/* Equivalent to (n * ceil(nbytes / n)) - nbytes */
#define _KTX_PADN_LEN(n, nbytes) \
(ktx_uint32_t)((n * ceilf((float)(nbytes) / n)) - (nbytes))
/*
* Pad nbytes to next multiple of 4
*/
#define _KTX_PAD4(nbytes) _KTX_PADN(4, nbytes)
/*
* Calculate bytes of of padding needed to reach next multiple of 4.
*/
#define _KTX_PAD4_LEN(nbytes) _KTX_PADN_LEN(4, nbytes)
/*
* Pad nbytes to next multiple of 8
*/
#define _KTX_PAD8(nbytes) _KTX_PADN(8, nbytes)
/*
* Calculate bytes of of padding needed to reach next multiple of 8.
*/
#define _KTX_PAD8_LEN(nbytes) _KTX_PADN_LEN(8, nbytes)
/*
* Pad nbytes to KTX_GL_UNPACK_ALIGNMENT
*/
#define _KTX_PAD_UNPACK_ALIGN(nbytes) \
_KTX_PADN(KTX_GL_UNPACK_ALIGNMENT, nbytes)
/*
* Calculate bytes of of padding needed to reach KTX_GL_UNPACK_ALIGNMENT.
*/
#define _KTX_PAD_UNPACK_ALIGN_LEN(nbytes) \
_KTX_PADN_LEN(KTX_GL_UNPACK_ALIGNMENT, nbytes)
/*
======================================
Internal utility functions
======================================
*/
void printKTX2Info2(ktxStream* src, KTX_header2* header);
#ifdef __cplusplus
}
#endif
#endif /* KTXINT_H */