test/jdk/java/awt/geom/Area/TransformPrecision.java

/*
 * Copyright (c) 2006, 2018, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

/*
 * @test
 * @bug 4632108
 * @summary Verifies that the Area transform methods maintain double precision
 */

import java.awt.Rectangle;
import java.awt.geom.AffineTransform;
import java.awt.geom.Area;

public class TransformPrecision {
    public static void main(String argv[]) {
        int x = 1 << 27;
        int y = 1 << 26;

        AffineTransform tx = AffineTransform.getTranslateInstance(x, y);
        AffineTransform untx = AffineTransform.getTranslateInstance(-x, -y);

        Rectangle r = new Rectangle(10, 10, 20, 20);
        Area a = new Area(r);

        Area b = new Area(r);
        b.transform(tx);
        b.transform(untx);
        if (!a.equals(b)) {
            throw new RuntimeException("large translation hurt precision!");
        }

        b = a.createTransformedArea(tx);
        b = b.createTransformedArea(untx);
        if (!a.equals(b)) {
            throw new RuntimeException("large translation hurt precision!");
        }
    }
}