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/*
* Copyright (c) 2012 Jason Polites
*
* 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 com.polites.android;
import android.graphics.PointF;
import android.util.FloatMath;
import android.view.MotionEvent;
public class MathUtils {
public static float distance(MotionEvent event) {
float x = event.getX(0) - event.getX(1);
float y = event.getY(0) - event.getY(1);
return FloatMath.sqrt(x * x + y * y);
}
public static float distance(PointF p1, PointF p2) {
float x = p1.x - p2.x;
float y = p1.y - p2.y;
return FloatMath.sqrt(x * x + y * y);
}
public static float distance(float x1, float y1, float x2, float y2) {
float x = x1 - x2;
float y = y1 - y2;
return FloatMath.sqrt(x * x + y * y);
}
public static void midpoint(MotionEvent event, PointF point) {
float x1 = event.getX(0);
float y1 = event.getY(0);
float x2 = event.getX(1);
float y2 = event.getY(1);
midpoint(x1, y1, x2, y2, point);
}
public static void midpoint(float x1, float y1, float x2, float y2, PointF point) {
point.x = (x1 + x2) / 2.0f;
point.y = (y1 + y2) / 2.0f;
}
/**
* Rotates p1 around p2 by angle degrees.
* @param p1
* @param p2
* @param angle
*/
public void rotate(PointF p1, PointF p2, float angle) {
float px = p1.x;
float py = p1.y;
float ox = p2.x;
float oy = p2.y;
p1.x = (FloatMath.cos(angle) * (px-ox) - FloatMath.sin(angle) * (py-oy) + ox);
p1.y = (FloatMath.sin(angle) * (px-ox) + FloatMath.cos(angle) * (py-oy) + oy);
}
public static float angle(PointF p1, PointF p2) {
return angle(p1.x, p1.y, p2.x, p2.y);
}
public static float angle(float x1, float y1, float x2, float y2) {
return (float) Math.atan2(y2 - y1, x2 - x1);
}
}
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