Rotates p1 around p2 by angle degrees. - Android java.lang

Android examples for java.lang:Math Trigonometric Function

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Description

Rotates p1 around p2 by angle degrees.

Demo Code


import android.graphics.PointF;
import android.util.FloatMath;
import android.view.MotionEvent;

public class Main{
    /**//from ww  w .  ja  v a2s.  com
     * Rotates p1 around p2 by angle degrees.
     *
     * @param p1
     * @param p2
     * @param angle
     */
    public static 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);
    }
}

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