macros.h
author tron
Sun, 22 May 2005 07:12:09 +0000
changeset 1852 9cfa8bf9d39f
parent 1556 4fd2c95e6bc4
child 1884 ae1d6213c6dd
permissions -rw-r--r--
(svn r2358) Add macros for getting (GB) and setting (SB) a range of bits
Use them exemplarily to prettify (Get|Set)Tile(Type|Height)
#ifndef MACROS_H
#define MACROS_H

#include "map.h"

#ifdef min
#undef min
#endif

#ifdef max
#undef max
#endif

static inline int min(int a, int b) { if (a <= b) return a; return b; }
static inline int max(int a, int b) { if (a >= b) return a; return b; }
static inline int64 max64(int64 a, int64 b) { if (a >= b) return a; return b; }

static inline uint minu(uint a, uint b) { if (a <= b) return a; return b; }
static inline uint maxu(uint a, uint b) { if (a >= b) return a; return b; }


static inline int clamp(int a, int min, int max)
{
	if (a <= min) return min;
	if (a >= max) return max;
	return a;
}


static inline int32 BIGMULSS(int32 a, int32 b, int shift) {
	return (int32)(((int64)(a) * (int64)(b)) >> (shift));
}

static inline int64 BIGMULSS64(int64 a, int64 b, int shift) {
	return ((a) * (b)) >> (shift);
}

static inline uint32 BIGMULUS(uint32 a, uint32 b, int shift) {
	return (uint32)(((uint64)(a) * (uint64)(b)) >> (shift));
}

static inline int64 BIGMULS(int32 a, int32 b) {
	return (int32)(((int64)(a) * (int64)(b)));
}

/* OPT: optimized into an unsigned comparison */
//#define IS_INSIDE_1D(x, base, size) ((x) >= (base) && (x) < (base) + (size))
#define IS_INSIDE_1D(x, base, size) ( (uint)((x) - (base)) < ((uint)(size)) )


#define HASBIT(x,y)    ((x) &   (1 << (y)))
#define SETBIT(x,y)    ((x) |=  (1 << (y)))
#define CLRBIT(x,y)    ((x) &= ~(1 << (y)))
#define TOGGLEBIT(x,y) ((x) ^=  (1 << (y)))

// checking more bits. Maybe unneccessary, but easy to use
#define HASBITS(x,y) ((x) & (y))
#define SETBITS(x,y) ((x) |= (y))
#define CLRBITS(x,y) ((x) &= ~(y))

#define PLAYER_SPRITE_COLOR(owner) ((_player_colors[owner] << 16) + 0x3070000)
#define SPRITE_PALETTE(x) ((x) + 0x8000)

extern const byte _ffb_64[128];
/* Returns the position of the first bit that is not zero, counted from the
 * left. Ie, 10110100 returns 2, 00000001 returns 0, etc. When x == 0 returns
 * 0.
 */
#define FIND_FIRST_BIT(x) _ffb_64[(x)]
/* Returns x with the first bit that is not zero, counted from the left, set
 * to zero. So, 10110100 returns 10110000, 00000001 returns 00000000, etc.
 */
#define KILL_FIRST_BIT(x) _ffb_64[(x)+64]

static inline int FindFirstBit2x64(int value)
{
/*
	int i = 0;
	if ( (byte) value == 0) {
		i += 8;
		value >>= 8;
	}
	return i + FIND_FIRST_BIT(value & 0x3F);

Faster ( or at least cleaner ) implementation below?
*/
	if ( (byte) value == 0) {
		return FIND_FIRST_BIT((value >> 8) & 0x3F) + 8;
	} else {
		return FIND_FIRST_BIT(value & 0x3F);
	}

}

static inline int KillFirstBit2x64(int value)
{
	if ( (byte) value == 0) {
		return KILL_FIRST_BIT((value >> 8) & 0x3F) << 8;
	} else {
		return value & (KILL_FIRST_BIT(value & 0x3F)|0x3F00);
	}
}

/* [min,max), strictly less than */
#define IS_BYTE_INSIDE(a,min,max) ((byte)((a)-(min)) < (byte)((max)-(min)))
#define IS_INT_INSIDE(a,min,max) ((uint)((a)-(min)) < (uint)((max)-(min)))


#define CHANCE16(a,b) ((uint16)Random() <= (uint16)((65536 * a) / b))
#define CHANCE16R(a,b,r) ((uint16)(r=Random()) <= (uint16)((65536 * a) / b))
#define CHANCE16I(a,b,v) ((uint16)(v) <= (uint16)((65536 * a) / b))

#define BEGIN_TILE_LOOP(var,w,h,tile)		\
		{int h_cur = h;									\
		uint var = tile;									\
		do {														\
			int w_cur = w;								\
			do {

#define END_TILE_LOOP(var,w,h,tile)			\
			} while (++var, --w_cur != 0);						\
		} while (var += TILE_XY(0,1) - (w), --h_cur != 0);}


#define for_each_bit(_i,_b)										\
	for(_i=0; _b!=0; _i++,_b>>=1)								\
		if (_b&1)

#define abs myabs


static inline int intxchg_(int *a, int b) { int t = *a; *a = b; return t; }
#define intswap(a,b) ((b) = intxchg_(&(a), (b)))

static inline int myabs(int a) { if (a<0) a = -a; return a; }
static inline int64 myabs64(int64 a) { if (a<0) a = -a; return a; }

static inline void swap_byte(byte *a, byte *b) { byte t = *a; *a = *b; *b = t; }
static inline void swap_uint16(uint16 *a, uint16 *b) { uint16 t = *a; *a = *b; *b = t; }
static inline void swap_int16(int16 *a, int16 *b) { int16 t = *a; *a = *b; *b = t; }
static inline void swap_int32(int32 *a, int32 *b) { int32 t = *a; *a = *b; *b = t; }
static inline void swap_tile(TileIndex *a, TileIndex *b) { TileIndex t = *a; *a = *b; *b = t; }



#if defined(TTD_LITTLE_ENDIAN)
#	define READ_LE_UINT16(b) (*(const uint16*)(b))
#elif defined(TTD_BIG_ENDIAN)
	static inline uint16 READ_LE_UINT16(const void *b) {
		return ((const byte*)b)[0] + (((const byte*)b)[1] << 8);
	}
#endif

// Fetch count bits starting at bit start from value
#define GB(value, start, count) (((value) >> (start)) & ((1 << (count)) - 1))
// Set count bits in value starting at bit start to data
#define SB(value, start, count, data) ((value) = ((value) & ~(((1 << (count)) - 1) << (start))) | ((data) << (start)))

#endif /* MACROS_H */