/*
* Copyright (C) 2011-2015, Peter Abeles. All Rights Reserved.
*
* This file is part of Geometric Regression Library (GeoRegression).
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package georegression.geometry;
import georegression.struct.GeoTuple2D_F64;
import georegression.struct.GeoTuple3D_F64;
import georegression.struct.point.Vector3D_F64;
/**
*
*
*/
public class UtilTrig_F64 {
public static double distance( double x0, double y0, double x1, double y1 ) {
double dx = x1 - x0;
double dy = y1 - y0;
return Math.sqrt( dx * dx + dy * dy );
}
public static double distanceSq( double x0, double y0, double x1, double y1 ) {
double dx = x1 - x0;
double dy = y1 - y0;
return dx * dx + dy * dy;
}
public static Vector3D_F64 cross( Vector3D_F64 a, Vector3D_F64 b ) {
double x = a.getY() * b.getZ() - a.getZ() * b.getY();
double y = a.getZ() * b.getX() - a.getX() * b.getZ();
double z = a.getX() * b.getY() - a.getY() * b.getX();
return new Vector3D_F64( x, y, z );
}
public static double dot( double vx_a, double vy_a,
double vx_b, double vy_b ) {
return vx_a * vx_b + vy_a * vy_b;
}
public static double dot( GeoTuple2D_F64 a , GeoTuple2D_F64 b ) {
return a.x*b.x + a.y*b.y;
}
public static double dot( GeoTuple3D_F64 a , GeoTuple3D_F64 b ) {
return a.x*b.x + a.y*b.y + a.z*b.z;
}
public static double acuteAngle( GeoTuple3D_F64 a , GeoTuple3D_F64 b ) {
double dot = a.x*b.x + a.y*b.y + a.z*b.z;
double bottom = a.norm()*b.norm();
return Math.acos(dot/bottom);
}
public static double acuteAngle( double vx_a, double vy_a,
double vx_b, double vy_b ) {
double r_a = Math.sqrt( vx_a * vx_a + vy_a * vy_a );
double r_b = Math.sqrt( vx_b * vx_b + vy_b * vy_b );
return Math.acos( ( vx_a * vx_b + vy_a * vy_b ) / ( r_a * r_b ) );
}
/**
* Normalizes the point such that the Frobenius norm is 1.
*
* @param p
*/
public static void normalize( GeoTuple3D_F64 p ) {
double n = p.norm();
p.x /= n;
p.y /= n;
p.z /= n;
}
}