Main.java Source code

Introduction

Here is the source code for Main.java

Source

//package com.java2s;
/*
 * Copyright 2016 GcsSloop
 *
 * 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.
 *
 * Last modified 2016-12-03 22:55:55
 *
 */

import android.graphics.Matrix;

public class Main {
    private static float transformAngle(Matrix m, float angleRadians) {
        // Construct and transform a vector oriented at the specified clockwise
        // angle from vertical.  Coordinate system: down is increasing Y, right is
        // increasing X.
        float[] v = new float[2];
        v[0] = (float) Math.sin(angleRadians);
        v[1] = (float) Math.cos(angleRadians);
        m.mapVectors(v);
        // Derive the transformed vector's clockwise angle from vertical.
        float result = (float) Math.atan2(v[0], -v[1]);
        if (result < -Math.PI / 2) {
            result += Math.PI;
        } else if (result > Math.PI / 2) {
            result -= Math.PI;
        }
        return result;
    }
}