ktxint.h

// Copyright eeGeo Ltd (2012-2014), All Rights Reserved

#pragma once

/* Define this to include the ETC unpack software in the library. */
#ifndef SUPPORT_SOFTWARE_ETC_UNPACK
//#define SUPPORT_SOFTWARE_ETC_UNPACK 1
#endif

#ifdef __cplusplus

#endif


#define KTX_IDENTIFIER_REF  { 0xAB, 0x4B, 0x54, 0x58, 0x20, 0x31, 0x31, 0xBB, 0x0D, 0x0A, 0x1A, 0x0A }
#define KTX_ENDIAN_REF      (0x04030201)
#define KTX_ENDIAN_REF_REV  (0x01020304)
#define KTX_HEADER_SIZE     (64)

typedef struct KTX_header_t {
    khronos_uint8_t  identifier[12];
    khronos_uint32_t endianness;
    khronos_uint32_t glType;
    khronos_uint32_t glTypeSize;
    khronos_uint32_t glFormat;
    khronos_uint32_t glInternalFormat;
    khronos_uint32_t glBaseInternalFormat;
    khronos_uint32_t pixelWidth;
    khronos_uint32_t pixelHeight;
    khronos_uint32_t pixelDepth;
    khronos_uint32_t numberOfArrayElements;
    khronos_uint32_t numberOfFaces;
    khronos_uint32_t numberOfMipmapLevels;
    khronos_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];

typedef struct KTX_texinfo_t {
    /* Data filled in by _ktxCheckHeader() */
    khronos_uint32_t textureDimensions;
    khronos_uint32_t glTarget;
    khronos_uint32_t compressed;
    khronos_uint32_t generateMipmaps;
} KTX_texinfo;

#ifndef GL_TEXTURE_1D
#define GL_TEXTURE_1D                    0x0DE0
#endif
#ifndef GL_TEXTURE_3D
#define GL_TEXTURE_3D                    0x806F
#endif
#ifndef GL_TEXTURE_CUBE_MAP
#define GL_TEXTURE_CUBE_MAP              0x8513
#define GL_TEXTURE_CUBE_MAP_POSITIVE_X   0x8515
#endif
/* from GL_EXT_texture_array */
#ifndef GL_TEXTURE_1D_ARRAY_EXT
#define GL_TEXTURE_1D_ARRAY_EXT          0x8C18
#define GL_TEXTURE_2D_ARRAY_EXT          0x8C1A
#endif
#ifndef GL_GENERATE_MIPMAP
#define GL_GENERATE_MIPMAP               0x8191
#endif

#ifndef GL_UNSIGNED_SHORT_5_6_5
#define GL_UNSIGNED_SHORT_5_6_5          0x8363
#endif
#ifndef GL_UNSIGNED_SHORT_4_4_4_4
#define GL_UNSIGNED_SHORT_4_4_4_4        0x8033
#endif
#ifndef GL_UNSIGNED_SHORT_5_5_5_1
#define GL_UNSIGNED_SHORT_5_5_5_1        0x8034
#endif

#ifndef GL_ETC1_RGB8_OES
#define GL_ETC1_RGB8_OES                 0x8D64
#endif


#ifndef MAX
#define MAX(x, y) (((x) > (y)) ? (x) : (y))
#endif

/* CheckHeader
 * 
 * Reads the KTX file header and performs some sanity checking on the values
 */
KTX_error_code _ktxCheckHeader(KTX_header* header, KTX_texinfo* texinfo);

/*
 * SwapEndian16: Swaps endianness in an array of 16-bit values
 */
void _ktxSwapEndian16(khronos_uint16_t* pData16, int count);

/*
 * SwapEndian32: Swaps endianness in an array of 32-bit values
 */
void _ktxSwapEndian32(khronos_uint32_t* pData32, int count);

/*
 * UncompressETC: uncompresses an ETC compressed texture image
 */
KTX_error_code _ktxUnpackETC(const GLubyte *srcETC, GLubyte **dstImage,
                             khronos_uint32_t active_width,
                             khronos_uint32_t active_height);

#ifdef __cplusplus
// }
#endif