Index: trunk/test/unit/org/openstreetmap/josm/gui/mappaint/MapCSSRendererTest.java
===================================================================
--- trunk/test/unit/org/openstreetmap/josm/gui/mappaint/MapCSSRendererTest.java	(revision 11433)
+++ trunk/test/unit/org/openstreetmap/josm/gui/mappaint/MapCSSRendererTest.java	(revision 11433)
@@ -0,0 +1,197 @@
+// License: GPL. For details, see LICENSE file.
+package org.openstreetmap.josm.gui.mappaint;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.fail;
+
+import java.awt.Point;
+import java.awt.image.BufferedImage;
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+import java.io.IOException;
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
+
+import javax.imageio.ImageIO;
+
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.Parameterized;
+import org.junit.runners.Parameterized.Parameters;
+import org.openstreetmap.josm.TestUtils;
+import org.openstreetmap.josm.data.Bounds;
+import org.openstreetmap.josm.data.osm.DataSet;
+import org.openstreetmap.josm.data.osm.visitor.paint.StyledMapRenderer;
+import org.openstreetmap.josm.gui.NavigatableComponent;
+import org.openstreetmap.josm.gui.mappaint.mapcss.MapCSSStyleSource;
+import org.openstreetmap.josm.gui.preferences.SourceEntry;
+import org.openstreetmap.josm.io.IllegalDataException;
+import org.openstreetmap.josm.io.OsmReader;
+import org.openstreetmap.josm.testutils.JOSMTestRules;
+
+import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
+
+/**
+ * Test cases for {@link StyledMapRenderer} and the MapCSS classes.
+ * <p>
+ * This test uses the data and reference files stored in the test data directory {@value #TEST_DATA_BASE}
+ * @author Michael Zangl
+ */
+@RunWith(Parameterized.class)
+public class MapCSSRendererTest {
+    private static final String TEST_DATA_BASE = "/renderer/";
+    /**
+     * lat = 0..1, lon = 0..1
+     */
+    private static final Bounds AREA_DEFAULT = new Bounds(0, 0, 1, 1);
+    private static final int IMAGE_SIZE = 256;
+
+    /**
+     * Minimal test rules required
+     */
+    @Rule
+    @SuppressFBWarnings(value = "URF_UNREAD_PUBLIC_OR_PROTECTED_FIELD")
+    public JOSMTestRules test = new JOSMTestRules().preferences().projection();
+
+    private TestConfig testConfig;
+
+    /**
+     * The different configurations of this test.
+     * @return The parameters.
+     */
+    @Parameters
+    public static Collection<Object[]> testRuns() {
+        return Stream.of(
+                /** Tests for StyledMapRenderer#drawNodeSymbol */
+                new TestConfig("node-shapes", AREA_DEFAULT),
+
+                /** Tests that StyledMapRenderer#drawWay respects width */
+                new TestConfig("way-width", AREA_DEFAULT)
+
+                ).map(e -> new Object[] {e})
+                .collect(Collectors.toList());
+    }
+
+    /**
+     * @param testConfig The config to use for this test.
+     */
+    public MapCSSRendererTest(TestConfig testConfig) {
+        this.testConfig = testConfig;
+    }
+
+    /**
+     * Run the test using {@link #testConfig}
+     * @throws Exception if an error occurs
+     */
+    @Test
+    public void render() throws Exception {
+        // load the data
+        DataSet dataSet = testConfig.getOsmDataSet();
+
+        // load the style
+        MapCSSStyleSource.STYLE_SOURCE_LOCK.writeLock().lock();
+        try {
+            MapPaintStyles.getStyles().clear();
+
+            MapCSSStyleSource source = new MapCSSStyleSource(testConfig.getStyleSourceEntry());
+            source.loadStyleSource();
+            if (!source.getErrors().isEmpty()) {
+                fail("Failed to load style file. Errors: " + source.getErrors());
+            }
+            MapPaintStyles.getStyles().setStyleSources(Arrays.asList(source));
+
+        } finally {
+            MapCSSStyleSource.STYLE_SOURCE_LOCK.writeLock().unlock();
+        }
+
+        // create the renderer
+        BufferedImage image = new BufferedImage(IMAGE_SIZE, IMAGE_SIZE, BufferedImage.TYPE_INT_ARGB);
+        NavigatableComponent nc = new NavigatableComponent() {
+            {
+                setBounds(0, 0, IMAGE_SIZE, IMAGE_SIZE);
+                updateLocationState();
+            }
+
+            @Override
+            protected boolean isVisibleOnScreen() {
+                return true;
+            }
+
+            @Override
+            public Point getLocationOnScreen() {
+                return new Point(0, 0);
+            }
+        };
+        nc.zoomTo(testConfig.testArea);
+        dataSet.allPrimitives().stream().forEach(n -> n.setHighlighted(n.isKeyTrue("highlight")));
+        new StyledMapRenderer(image.createGraphics(), nc, false).render(dataSet, false, testConfig.testArea);
+
+        BufferedImage reference = testConfig.getReference();
+
+        // now compute differences:
+        assertEquals(IMAGE_SIZE, reference.getWidth());
+        assertEquals(IMAGE_SIZE, reference.getHeight());
+
+        StringBuilder differences = new StringBuilder();
+
+        for (int y = 0; y < reference.getHeight(); y++) {
+            for (int x = 0; x < reference.getWidth(); x++) {
+                int expected = reference.getRGB(x, y);
+                int result = image.getRGB(x, y);
+                if (expected != result && differences.length() < 500) {
+                    differences.append("\nDifference at ")
+                               .append(x)
+                               .append(",")
+                               .append(y)
+                               .append(": Expected ")
+                               .append(Integer.toHexString(expected))
+                               .append(" but got ")
+                               .append(Integer.toHexString(result));
+                }
+            }
+        }
+
+        if (differences.length() > 0) {
+            // You can use this to debug:
+            ImageIO.write(image, "png", new File(testConfig.getTestDirectory() + "/test-output.png"));
+            fail("Images for test " + testConfig.testDirectory + " differ: " + differences.toString());
+        }
+    }
+
+    private static class TestConfig {
+        private final String testDirectory;
+        private final Bounds testArea;
+
+        TestConfig(String testDirectory, Bounds testArea) {
+            this.testDirectory = testDirectory;
+            this.testArea = testArea;
+        }
+
+        public BufferedImage getReference() throws IOException {
+            return ImageIO.read(new File(getTestDirectory() + "/reference.png"));
+        }
+
+        private String getTestDirectory() {
+            return TestUtils.getTestDataRoot() + TEST_DATA_BASE + testDirectory;
+        }
+
+        public SourceEntry getStyleSourceEntry() {
+            return new SourceEntry(getTestDirectory() + "/style.mapcss",
+                    "test style", "a test style", true // active
+            );
+        }
+
+        public DataSet getOsmDataSet() throws FileNotFoundException, IllegalDataException {
+            return OsmReader.parseDataSet(new FileInputStream(getTestDirectory() + "/data.osm"), null);
+        }
+
+        @Override
+        public String toString() {
+            return "TestConfig [testDirectory=" + testDirectory + ", testArea=" + testArea + ']';
+        }
+    }
+}