/*

 * Hedgewars-iOS, a Hedgewars port for iOS devices

 * Copyright (c) 2009-2011 Vittorio Giovara <vittorio.giovara@gmail.com>

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License as published by

 * the Free Software Foundation; version 2 of the License

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA.

 */

#include "CGPointUtils.h"

#include "math.h"

CGFloat distanceBetweenPoints (CGPoint first, CGPoint second) {

    CGFloat deltaX = second.x - first.x;

    CGFloat deltaY = second.y - first.y;

    return sqrt(deltaX*deltaX + deltaY*deltaY );

}

CGFloat angleBetweenPoints(CGPoint first, CGPoint second) {

    CGFloat height = second.y - first.y;

    CGFloat width = first.x - second.x;

    CGFloat rads = atan(height/width);

    return radiansToDegrees(rads);

}

CGFloat angleBetweenLines(CGPoint line1Start, CGPoint line1End, CGPoint line2Start, CGPoint line2End) {

    CGFloat a = line1End.x - line1Start.x;

    CGFloat b = line1End.y - line1Start.y;

    CGFloat c = line2End.x - line2Start.x;

    CGFloat d = line2End.y - line2Start.y;

    CGFloat rads = acos(((a*c) + (b*d)) / ((sqrt(a*a + b*b)) * (sqrt(c*c + d*d))));

    return radiansToDegrees(rads);

}

CGFloat CGPointDot(CGPoint a,CGPoint b) {

    return a.x*b.x+a.y*b.y;

}

CGFloat CGPointLen(CGPoint a) {

    return sqrtf(a.x*a.x+a.y*a.y);

}

CGPoint CGPointSub(CGPoint a,CGPoint b) {

    CGPoint c = {a.x-b.x,a.y-b.y};

    return c;

}

CGFloat CGPointDist(CGPoint a,CGPoint b) {

    CGPoint c = CGPointSub(a,b);

    return CGPointLen(c);

}

CGPoint CGPointNorm(CGPoint a) {

    CGFloat m = sqrtf(a.x*a.x+a.y*a.y);

    CGPoint c;

    c.x = a.x/m;

    c.y = a.y/m;

    return c;

}