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diff --git a/subprojects/viatra-runtime-rete/src/main/java/tools/refinery/viatra/runtime/rete/itc/graphimpl/DotGenerator.java b/subprojects/viatra-runtime-rete/src/main/java/tools/refinery/viatra/runtime/rete/itc/graphimpl/DotGenerator.java
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+++ b/subprojects/viatra-runtime-rete/src/main/java/tools/refinery/viatra/runtime/rete/itc/graphimpl/DotGenerator.java
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+/*******************************************************************************
+ * Copyright (c) 2010-2019, Tamas Szabo, Istvan Rath and Daniel Varro
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License v. 2.0 which is available at
+ * http://www.eclipse.org/legal/epl-v20.html.
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ *******************************************************************************/
+package tools.refinery.viatra.runtime.rete.itc.graphimpl;
+
+import tools.refinery.viatra.runtime.rete.itc.alg.misc.scc.SCC;
+import tools.refinery.viatra.runtime.rete.itc.alg.misc.scc.SCCResult;
+import tools.refinery.viatra.runtime.matchers.util.IMemoryView;
+
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Set;
+import java.util.function.Function;
+
+/**
+ * This class contains utility methods to generate dot representations for {@link Graph} instances.
+ *
+ * @author Tamas Szabo
+ * @since 2.3
+ */
+public class DotGenerator {
+
+    private static final String[] colors = new String[] { "yellow", "blue", "red", "green", "gray", "cyan" };
+
+    private DotGenerator() {
+
+    }
+
+    /**
+     * Generates the dot representation for the given graph.
+     *
+     * @param graph
+     *            the graph
+     * @param colorSCCs
+     *            specifies if the strongly connected components with size greater than shall be colored
+     * @param nameFunction
+     *            use this function to provide custom names to nodes, null if the default toString shall be used
+     * @param colorFunction
+     *            use this function to provide custom color to nodes, null if the default white color shall be used
+     * @param edgeFunction
+     *            use this function to provide custom edge labels, null if no edge label shall be printed
+     * @return the dot representation as a string
+     */
+    public static <V> String generateDot(final Graph<V> graph, final boolean colorSCCs,
+            final Function<V, String> nameFunction, final Function<V, String> colorFunction,
+            final Function<V, Function<V, String>> edgeFunction) {
+        final Map<V, String> colorMap = new HashMap<V, String>();
+
+        if (colorSCCs) {
+            final SCCResult<V> result = SCC.computeSCC(graph);
+            final Set<Set<V>> sccs = result.getSccs();
+
+            int i = 0;
+            for (final Set<V> scc : sccs) {
+                if (scc.size() > 1) {
+                    for (final V node : scc) {
+                        final String color = colorMap.get(node);
+                        if (color == null) {
+                            colorMap.put(node, colors[i % colors.length]);
+                        } else {
+                            colorMap.put(node, colorMap.get(node) + ":" + colors[i % colors.length]);
+                        }
+                    }
+                    i++;
+                }
+            }
+
+            // if a node has no color yet, then make it white
+            for (final V node : graph.getAllNodes()) {
+                if (!colorMap.containsKey(node)) {
+                    colorMap.put(node, "white");
+                }
+            }
+        } else {
+            for (final V node : graph.getAllNodes()) {
+                colorMap.put(node, "white");
+            }
+        }
+
+        if (colorFunction != null) {
+            for (final V node : graph.getAllNodes()) {
+                colorMap.put(node, colorFunction.apply(node));
+            }
+        }
+
+        final StringBuilder builder = new StringBuilder();
+        builder.append("digraph g {\n");
+
+        for (final V node : graph.getAllNodes()) {
+            final String nodePresentation = nameFunction == null ? node.toString() : nameFunction.apply(node);
+            builder.append("\"" + nodePresentation + "\"");
+            builder.append("[style=filled,fillcolor=" + colorMap.get(node) + "]");
+            builder.append(";\n");
+        }
+
+        for (final V source : graph.getAllNodes()) {
+            final IMemoryView<V> targets = graph.getTargetNodes(source);
+            if (!targets.isEmpty()) {
+                final String sourcePresentation = nameFunction == null ? source.toString() : nameFunction.apply(source);
+                for (final V target : targets.distinctValues()) {
+                    String edgeLabel = null;
+                    if (edgeFunction != null) {
+                        final Function<V, String> v1 = edgeFunction.apply(source);
+                        if (v1 != null) {
+                            edgeLabel = v1.apply(target);
+                        }
+                    }
+
+                    final String targetPresentation = nameFunction == null ? target.toString()
+                            : nameFunction.apply(target);
+
+                    builder.append("\"" + sourcePresentation + "\" -> \"" + targetPresentation + "\"");
+                    if (edgeLabel != null) {
+                        builder.append("[label=\"" + edgeLabel + "\"]");
+                    }
+                    builder.append(";\n");
+                }
+            }
+        }
+
+        builder.append("}");
+        return builder.toString();
+    }
+
+    /**
+     * Generates the dot representation for the given graph. No special pretty printing customization will be applied.
+     *
+     * @param graph
+     *            the graph
+     * @return the dot representation as a string
+     */
+    public static <V> String generateDot(final Graph<V> graph) {
+        return generateDot(graph, false, null, null, null);
+    }
+
+    /**
+     * Returns a simple name shortener function that can be used in the graphviz visualization to help with readability.
+     * WARNING: if you shorten the name of the {@link Node}s too much, the visualization may become incorrect because
+     * grahpviz will treat different nodes as the same if their shortened names are the same.
+     *
+     * @param maxLength
+     *            the maximum length of the text that is kept from the toString of the objects in the graph
+     * @return the shrunk toString value
+     */
+    public static <V> Function<V, String> getNameShortener(final int maxLength) {
+        return new Function<V, String>() {
+            @Override
+            public String apply(final V obj) {
+                final String value = obj.toString();
+                return value.substring(0, Math.min(value.length(), maxLength));
+            }
+        };
+    }
+
+}