/*

 MathUtils.h

 Defines some standard math things that we'll need

 Author: CP

 Copyright (c) 2002, Apple Computer, Inc., all rights reserved.

*/

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#import <Foundation/Foundation.h>

#define ToRad(deg)      ( (M_PI * (deg)) / 180.0 )

#define ToDeg(rad)      ( (180.0 * (rad)) / M_PI )

#define SQR(x)          ( (x) * (x) )

// Given the vector v from p1 to p2, computes the angle in degrees between v and the compared vector <0,1> (<0,-1> if flipped).

// The returned angle is in the range [0,360).

//

static inline float AngleFromNorth(NSPoint p1, NSPoint p2, BOOL flipped) {

    NSPoint v = NSMakePoint(p2.x-p1.x,p2.y-p1.y);

    float vmag = sqrt(SQR(v.x) + SQR(v.y)), result = 0;

    v.x /= vmag;

    v.y /= vmag;

    result = ToDeg(atan2(v.x,(flipped ? -v.y : v.y)));

    return (result >=0  ? result : result + 360.0);

}