/*
* 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_F32;
import georegression.struct.GeoTuple3D_F32;
import georegression.struct.point.Vector3D_F32;
/**
*
*
*/
public class UtilTrig_F32 {
public static float distance( float x0, float y0, float x1, float y1 ) {
float dx = x1 - x0;
float dy = y1 - y0;
return (float)Math.sqrt( dx * dx + dy * dy );
}
public static float distanceSq( float x0, float y0, float x1, float y1 ) {
float dx = x1 - x0;
float dy = y1 - y0;
return dx * dx + dy * dy;
}
public static Vector3D_F32 cross( Vector3D_F32 a, Vector3D_F32 b ) {
float x = a.getY() * b.getZ() - a.getZ() * b.getY();
float y = a.getZ() * b.getX() - a.getX() * b.getZ();
float z = a.getX() * b.getY() - a.getY() * b.getX();
return new Vector3D_F32( x, y, z );
}
public static float dot( float vx_a, float vy_a,
float vx_b, float vy_b ) {
return vx_a * vx_b + vy_a * vy_b;
}
public static float dot( GeoTuple2D_F32 a , GeoTuple2D_F32 b ) {
return a.x*b.x + a.y*b.y;
}
public static float dot( GeoTuple3D_F32 a , GeoTuple3D_F32 b ) {
return a.x*b.x + a.y*b.y + a.z*b.z;
}
public static float acuteAngle( GeoTuple3D_F32 a , GeoTuple3D_F32 b ) {
float dot = a.x*b.x + a.y*b.y + a.z*b.z;
float bottom = a.norm()*b.norm();
return (float)Math.acos(dot/bottom);
}
public static float acuteAngle( float vx_a, float vy_a,
float vx_b, float vy_b ) {
float r_a = (float)Math.sqrt( vx_a * vx_a + vy_a * vy_a );
float r_b = (float)Math.sqrt( vx_b * vx_b + vy_b * vy_b );
return (float)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_F32 p ) {
float n = p.norm();
p.x /= n;
p.y /= n;
p.z /= n;
}
}