Source code of Windows XP (NT5)
You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
 
 
 
 
 
 

47 lines
1.1 KiB

// mathx.h
#ifndef __INCLUDE_MATHX
#define __INCLUDE_MATHX
#ifdef __cplusplus
extern "C"
{
#endif
int Arctan2(int y, int x);
int Distance(int dX, int dY);
#define DISTANCE_POINT(a,b) Distance((a).x - (b).x, (a).y - (b).y)
#define CROSS_PRODUCT(a,b) (((long) (a).x) * ((long) (b).y) - ((long) (a).y) * ((long) (b).x))
// Calculate difference between two angles and bring into range -180 < angle <= 180.
#define ANGLEDIFF(a,b,c) { \
c = b - a; \
if (c > 180) { \
c -= 360; \
} else if (c <= -180) { \
c += 360; \
} \
}
// Calc d = the angle betw (the extension of rgxy[a]:rgxy[b]) and
// (rgxy[b]:rgxy[c]). The sign of d reflects clockwise vs
// counterclockwise turns.
// LEFT FOR A RAINY DAY: make this more efficient
#define CALCANGLE(a,b,c,d) \
ANGLEDIFF(Arctan2(rgxy[b].y - rgxy[a].y, rgxy[b].x - rgxy[a].x), \
Arctan2(rgxy[c].y - rgxy[b].y, rgxy[c].x - rgxy[b].x), \
d);
#define CALCANGLEPT(a,b,c,d) \
ANGLEDIFF(Arctan2(b.y - a.y, b.x - a.x), \
Arctan2(c.y - b.y, c.x - b.x), \
d);
#ifdef __cplusplus
};
#endif
#endif //__INCLUDE_MATHX