JDK-8316741: fixed BasicStroke.createStrokedShape miter-limits failin…

…g on small shapes

src/test/java/TestCreateStrokedShapeJoins.java

@@ -0,0 +1,104 @@
+/*
+ * Copyright (c) 2023, 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.
+ */
+
+import java.io.*;
+import java.awt.*;
+import java.awt.image.*;
+import java.awt.geom.*;
+import java.util.Arrays;
+import javax.imageio.*;
+
+/**
+ * @test
+ * @bug 8316741
+ * @summary Verifies that Marlin renderer's Stroker generates properly joins
+ * in createStrokedShape()
+ * @run main TestCreateStrokedShapeJoins
+ */
+public class TestCreateStrokedShapeJoins {
+
+ static final boolean SAVE_IMAGE = false;
+
+ private final static int W = 200;
+
+ private final static int[] REF_COUNTS = new int[]{4561, 4790, 5499};
+
+ public static void main(String[] args) throws Exception {
+ final int[] test = new int[]{
+ test(BasicStroke.JOIN_BEVEL),
+ test(BasicStroke.JOIN_ROUND),
+ test(BasicStroke.JOIN_MITER)
+ };
+
+ System.out.println("test: " + Arrays.toString(test));
+ System.out.println("ref: " + Arrays.toString(REF_COUNTS));
+
+ // check results:
+ for (int i = 0; i < REF_COUNTS.length; i++) {
+ if (test[i] != REF_COUNTS[i]) {
+ throw new RuntimeException("Invalid test[" + i + "]: " + test[i] + " != " + REF_COUNTS[i]);
+ }
+ }
+ }
+
+ private static int test(int join) throws Exception {
+ final BufferedImage image = new BufferedImage(W, W, BufferedImage.TYPE_INT_ARGB);
+ final Graphics2D g = image.createGraphics();
+ try {
+ g.setPaint(Color.BLACK);
+ g.fillRect(0, 0, W, W);
+ g.setPaint(Color.WHITE);
+ g.setTransform(new AffineTransform(W, 0, 0, W, 0, 0));
+
+ final BasicStroke stroke = new BasicStroke(0.15f, 0, join, 10);
+
+ final Path2D p = new Path2D.Float();
+ p.moveTo(0.95f, 0.6f);
+ p.lineTo(0.5f, 0.5f);
+ p.lineTo(0.95f, 0.4f);
+
+ final Shape outline = stroke.createStrokedShape(p);
+ g.fill(outline);
+ } finally {
+ g.dispose();
+ }
+ if (SAVE_IMAGE) {
+ final File file = new File("TestCreateStrokedShapeJoins-" + join + ".png");
+ System.out.println("Writing " + file.getAbsolutePath());
+ ImageIO.write(image, "png", file);
+ }
+ int count = 0;
+
+ for (int y = 0; y < W; y++) {
+ for (int x = 0; x < W; x++) {
+ final int rgb = image.getRGB(x, y);
+ final int b = rgb & 0xFF;
+
+ if (b != 0) {
+ count++;
+ }
+ }
+ }
+ return count;
+ }
+}