/*====================================================================*
- Copyright (C) 2001 Leptonica. All rights reserved.
- This software is distributed in the hope that it will be
- useful, but with NO WARRANTY OF ANY KIND.
- No author or distributor accepts responsibility to anyone for the
- consequences of using this software, or for whether it serves any
- particular purpose or works at all, unless he or she says so in
- writing. Everyone is granted permission to copy, modify and
- redistribute this source code, for commercial or non-commercial
- purposes, with the following restrictions: (1) the origin of this
- source code must not be misrepresented; (2) modified versions must
- be plainly marked as such; and (3) this notice may not be removed
- or altered from any source or modified source distribution.
*====================================================================*/
#ifndef LEPTONICA_ARRAY_ACCESS_H
#define LEPTONICA_ARRAY_ACCESS_H
/*
* arrayaccess.h
*
* 1, 2, 4, 8, 16 and 32 bit data access within an array of 32-bit words
*
* This is used primarily to access 1, 2, 4, 8, 16 and 32 bit pixels
* in a line of image data, represented as an array of 32-bit words.
*
* pdata: pointer to first 32-bit word in the array
* n: index of the pixel in the array
*
* Function calls for these accessors are defined in arrayaccess.c.
*
* However, for efficiency we use the inline macros for all accesses.
* Even though the 2 and 4 bit set* accessors are more complicated,
* they are about 10% faster than the function calls.
*
* The 32 bit access is just a cast and ptr arithmetic. We include
* it so that the input ptr can be void*.
*
* At the end of this file is code for invoking the function calls
* instead of inlining.
*
* The macro SET_DATA_BIT_VAL(pdata, n, val) is a bit slower than
* if (val == 0)
* CLEAR_DATA_BIT(pdata, n);
* else
* SET_DATA_BIT(pdata, n);
*/
#if 1 /* Inline Accessors */
#ifndef COMPILER_MSVC
/*--------------------------------------------------*
* 1 bit access *
*--------------------------------------------------*/
#define GET_DATA_BIT(pdata, n) \
((*((l_uint32 *)(pdata) + ((n) >> 5)) >> (31 - ((n) & 31))) & 1)
#define SET_DATA_BIT(pdata, n) \
(*((l_uint32 *)(pdata) + ((n) >> 5)) |= (0x80000000 >> ((n) & 31)))
#define CLEAR_DATA_BIT(pdata, n) \
(*((l_uint32 *)(pdata) + ((n) >> 5)) &= ~(0x80000000 >> ((n) & 31)))
#define SET_DATA_BIT_VAL(pdata, n, val) \
({l_uint32 *_TEMP_WORD_PTR_; \
_TEMP_WORD_PTR_ = (l_uint32 *)(pdata) + ((n) >> 5); \
*_TEMP_WORD_PTR_ &= ~(0x80000000 >> ((n) & 31)); \
*_TEMP_WORD_PTR_ |= ((val) << (31 - ((n) & 31))); \
})
/*--------------------------------------------------*
* 2 bit access *
*--------------------------------------------------*/
#define GET_DATA_DIBIT(pdata, n) \
((*((l_uint32 *)(pdata) + ((n) >> 4)) >> (2 * (15 - ((n) & 15)))) & 3)
#define SET_DATA_DIBIT(pdata, n, val) \
({l_uint32 *_TEMP_WORD_PTR_; \
_TEMP_WORD_PTR_ = (l_uint32 *)(pdata) + ((n) >> 4); \
*_TEMP_WORD_PTR_ &= ~(0xc0000000 >> (2 * ((n) & 15))); \
*_TEMP_WORD_PTR_ |= ((val) << (30 - 2 * ((n) & 15))); \
})
#define CLEAR_DATA_DIBIT(pdata, n) \
(*((l_uint32 *)(pdata) + ((n) >> 4)) &= ~(0xc0000000 >> (2 * ((n) & 15))))
/*--------------------------------------------------*
* 4 bit access *
*--------------------------------------------------*/
#define GET_DATA_QBIT(pdata, n) \
((*((l_uint32 *)(pdata) + ((n) >> 3)) >> (4 * (7 - ((n) & 7)))) & 0xf)
#define SET_DATA_QBIT(pdata, n, val) \
({l_uint32 *_TEMP_WORD_PTR_; \
_TEMP_WORD_PTR_ = (l_uint32 *)(pdata) + ((n) >> 3); \
*_TEMP_WORD_PTR_ &= ~(0xf0000000 >> (4 * ((n) & 7))); \
*_TEMP_WORD_PTR_ |= ((val) << (28 - 4 * ((n) & 7))); \
})
#define CLEAR_DATA_QBIT(pdata, n) \
(*((l_uint32 *)(pdata) + ((n) >> 3)) &= ~(0xf0000000 >> (4 * ((n) & 7))))
/*--------------------------------------------------*
* 8 bit access *
*--------------------------------------------------*/
#ifdef L_BIG_ENDIAN
#define GET_DATA_BYTE(pdata, n) \
(*((l_uint8 *)(pdata) + (n)))
#else /* L_LITTLE_ENDIAN */
#define GET_DATA_BYTE(pdata, n) \
(*(l_uint8 *)((l_uintptr_t)((l_uint8 *)(pdata) + (n)) ^ 3))
#endif /* L_BIG_ENDIAN */
#ifdef L_BIG_ENDIAN
#define SET_DATA_BYTE(pdata, n, val) \
(*((l_uint8 *)(pdata) + (n)) = (val))
#else /* L_LITTLE_ENDIAN */
#define SET_DATA_BYTE(pdata, n, val) \
(*(l_uint8 *)((l_uintptr_t)((l_uint8 *)(pdata) + (n)) ^ 3) = (val))
#endif /* L_BIG_ENDIAN */
/*--------------------------------------------------*
* 16 bit access *
*--------------------------------------------------*/
#ifdef L_BIG_ENDIAN
#define GET_DATA_TWO_BYTES(pdata, n) \
(*((l_uint16 *)(pdata) + (n)))
#else /* L_LITTLE_ENDIAN */
#define GET_DATA_TWO_BYTES(pdata, n) \
(*(l_uint16 *)((l_uintptr_t)((l_uint16 *)(pdata) + (n)) ^ 2))
#endif /* L_BIG_ENDIAN */
#ifdef L_BIG_ENDIAN
#define SET_DATA_TWO_BYTES(pdata, n, val) \
(*((l_uint16 *)(pdata) + (n)) = (val))
#else /* L_LITTLE_ENDIAN */
#define SET_DATA_TWO_BYTES(pdata, n, val) \
(*(l_uint16 *)((l_uintptr_t)((l_uint16 *)(pdata) + (n)) ^ 2) = (val))
#endif /* L_BIG_ENDIAN */
/*--------------------------------------------------*
* 32 bit access *
*--------------------------------------------------*/
#define GET_DATA_FOUR_BYTES(pdata, n) \
(*((l_uint32 *)(pdata) + (n)))
#define SET_DATA_FOUR_BYTES(pdata, n, val) \
(*((l_uint32 *)(pdata) + (n)) = (val))
#endif /* COMPILER_MSVC */
#endif /* Inline Accessors */
/*--------------------------------------------------*
* Slower, using function calls for all accessors *
*--------------------------------------------------*/
#if 0 || COMPILER_MSVC
#define GET_DATA_BIT(pdata, n) l_getDataBit(pdata, n)
#define SET_DATA_BIT(pdata, n) l_setDataBit(pdata, n)
#define CLEAR_DATA_BIT(pdata, n) l_clearDataBit(pdata, n)
#define SET_DATA_BIT_VAL(pdata, n, val) l_setDataBitVal(pdata, n, val)
#define GET_DATA_DIBIT(pdata, n) l_getDataDibit(pdata, n)
#define SET_DATA_DIBIT(pdata, n, val) l_setDataDibit(pdata, n, val)
#define CLEAR_DATA_DIBIT(pdata, n) l_clearDataDibit(pdata, n)
#define GET_DATA_QBIT(pdata, n) l_getDataQbit(pdata, n)
#define SET_DATA_QBIT(pdata, n, val) l_setDataQbit(pdata, n, val)
#define CLEAR_DATA_QBIT(pdata, n) l_clearDataQbit(pdata, n)
#define GET_DATA_BYTE(pdata, n) l_getDataByte(pdata, n)
#define SET_DATA_BYTE(pdata, n, val) l_setDataByte(pdata, n, val)
#define GET_DATA_TWO_BYTES(pdata, n) l_getDataTwoBytes(pdata, n)
#define SET_DATA_TWO_BYTES(pdata, n, val) l_setDataTwoBytes(pdata, n, val)
#define GET_DATA_FOUR_BYTES(pdata, n) l_getDataFourBytes(pdata, n)
#define SET_DATA_FOUR_BYTES(pdata, n, val) l_setDataFourBytes(pdata, n, val)
#endif
#endif /* LEPTONICA_ARRAY_ACCESS_H */