Tree Layout with vertical position constraints

features/org.eclipse.elk.algorithms.feature/feature.xml

@@ -101,5 +101,12 @@ SPDX-License-Identifier: EPL-2.0
          install-size="0"
          version="0.0.0"
          unpack="false"/>
+
+   <plugin
+         id="org.eclipse.elk.alg.vertiflex"
+         download-size="0"
+         install-size="0"
+         version="0.0.0"
+         unpack="false"/>
 
 </feature>

plugins/org.eclipse.elk.alg.vertiflex/.classpath

@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<classpath>
+	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/JavaSE-1.8"/>
+	<classpathentry kind="con" path="org.eclipse.pde.core.requiredPlugins"/>
+	<classpathentry kind="src" path="src"/>
+	<classpathentry kind="src" path="src-gen"/>
+	<classpathentry kind="output" path="bin"/>
+</classpath>

plugins/org.eclipse.elk.alg.vertiflex/.project

@@ -0,0 +1,46 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<projectDescription>
+	<name>org.eclipse.elk.alg.vertiflex</name>
+	<comment></comment>
+	<projects>
+	</projects>
+	<buildSpec>
+		<buildCommand>
+			<name>org.eclipse.xtext.ui.shared.xtextBuilder</name>
+			<arguments>
+			</arguments>
+		</buildCommand>
+		<buildCommand>
+			<name>org.eclipse.jdt.core.javabuilder</name>
+			<arguments>
+			</arguments>
+		</buildCommand>
+		<buildCommand>
+			<name>org.eclipse.pde.ManifestBuilder</name>
+			<arguments>
+			</arguments>
+		</buildCommand>
+		<buildCommand>
+			<name>org.eclipse.pde.SchemaBuilder</name>
+			<arguments>
+			</arguments>
+		</buildCommand>
+		<buildCommand>
+			<name>net.sf.eclipsecs.core.CheckstyleBuilder</name>
+			<arguments>
+			</arguments>
+		</buildCommand>
+		<buildCommand>
+			<name>org.eclipse.m2e.core.maven2Builder</name>
+			<arguments>
+			</arguments>
+		</buildCommand>
+	</buildSpec>
+	<natures>
+		<nature>org.eclipse.m2e.core.maven2Nature</nature>
+		<nature>org.eclipse.pde.PluginNature</nature>
+		<nature>org.eclipse.jdt.core.javanature</nature>
+		<nature>net.sf.eclipsecs.core.CheckstyleNature</nature>
+		<nature>org.eclipse.xtext.ui.shared.xtextNature</nature>
+	</natures>
+</projectDescription>

plugins/org.eclipse.elk.alg.vertiflex/.settings/org.eclipse.jdt.ui.prefs

@@ -0,0 +1,5 @@
+eclipse.preferences.version=1
+formatter_profile=_Elk
+formatter_settings_version=12
+org.eclipse.jdt.ui.javadoc=true
+org.eclipse.jdt.ui.text.custom_code_templates=<?xml version\="1.0" encoding\="UTF-8" standalone\="no"?><templates><template autoinsert\="true" context\="gettercomment_context" deleted\="false" description\="Comment for getter method" enabled\="true" id\="org.eclipse.jdt.ui.text.codetemplates.gettercomment" name\="gettercomment">/**\n * @return the ${bare_field_name}\n */</template><template autoinsert\="true" context\="settercomment_context" deleted\="false" description\="Comment for setter method" enabled\="true" id\="org.eclipse.jdt.ui.text.codetemplates.settercomment" name\="settercomment">/**\n * @param ${param} the ${bare_field_name} to set\n */</template><template autoinsert\="true" context\="constructorcomment_context" deleted\="false" description\="Comment for created constructors" enabled\="true" id\="org.eclipse.jdt.ui.text.codetemplates.constructorcomment" name\="constructorcomment">/**\n * ${tags}\n */</template><template autoinsert\="false" context\="filecomment_context" deleted\="false" description\="Comment for created Java files" enabled\="true" id\="org.eclipse.jdt.ui.text.codetemplates.filecomment" name\="filecomment">/*******************************************************************************\n * Copyright (c) ${year} ${user} and others.\n * \n * This program and the accompanying materials are made available under the\n * terms of the Eclipse Public License 2.0 which is available at\n * http://www.eclipse.org/legal/epl-2.0.\n * \n * SPDX-License-Identifier: EPL-2.0 \n *******************************************************************************/</template><template autoinsert\="true" context\="typecomment_context" deleted\="false" description\="Comment for created types" enabled\="true" id\="org.eclipse.jdt.ui.text.codetemplates.typecomment" name\="typecomment">/**\n * @author ${user}\n *\n * ${tags}\n */</template><template autoinsert\="true" context\="fieldcomment_context" deleted\="false" description\="Comment for fields" enabled\="true" id\="org.eclipse.jdt.ui.text.codetemplates.fieldcomment" name\="fieldcomment">/**\n * \n */</template><template autoinsert\="true" context\="methodcomment_context" deleted\="false" description\="Comment for non-overriding methods" enabled\="true" id\="org.eclipse.jdt.ui.text.codetemplates.methodcomment" name\="methodcomment">/**\n * ${tags}\n */</template><template autoinsert\="true" context\="overridecomment_context" deleted\="false" description\="Comment for overriding methods" enabled\="true" id\="org.eclipse.jdt.ui.text.codetemplates.overridecomment" name\="overridecomment">/* (non-Javadoc)\n * ${see_to_overridden}\n */</template><template autoinsert\="true" context\="delegatecomment_context" deleted\="false" description\="Comment for delegate methods" enabled\="true" id\="org.eclipse.jdt.ui.text.codetemplates.delegatecomment" name\="delegatecomment">/**\n * ${tags}\n * ${see_to_target}\n */</template><template autoinsert\="true" context\="newtype_context" deleted\="false" description\="Newly created files" enabled\="true" id\="org.eclipse.jdt.ui.text.codetemplates.newtype" name\="newtype">${filecomment}\n${package_declaration}\n\n${typecomment}\n${type_declaration}</template><template autoinsert\="true" context\="classbody_context" deleted\="false" description\="Code in new class type bodies" enabled\="true" id\="org.eclipse.jdt.ui.text.codetemplates.classbody" name\="classbody">\n</template><template autoinsert\="true" context\="interfacebody_context" deleted\="false" description\="Code in new interface type bodies" enabled\="true" id\="org.eclipse.jdt.ui.text.codetemplates.interfacebody" name\="interfacebody">\n</template><template autoinsert\="true" context\="enumbody_context" deleted\="false" description\="Code in new enum type bodies" enabled\="true" id\="org.eclipse.jdt.ui.text.codetemplates.enumbody" name\="enumbody">\n</template><template autoinsert\="true" context\="annotationbody_context" deleted\="false" description\="Code in new annotation type bodies" enabled\="true" id\="org.eclipse.jdt.ui.text.codetemplates.annotationbody" name\="annotationbody">\n</template><template autoinsert\="true" context\="catchblock_context" deleted\="false" description\="Code in new catch blocks" enabled\="true" id\="org.eclipse.jdt.ui.text.codetemplates.catchblock" name\="catchblock">// ${todo} Auto-generated catch block\n${exception_var}.printStackTrace();</template><template autoinsert\="true" context\="methodbody_context" deleted\="false" description\="Code in created method stubs" enabled\="true" id\="org.eclipse.jdt.ui.text.codetemplates.methodbody" name\="methodbody">// ${todo} Auto-generated method stub\n${body_statement}</template><template autoinsert\="true" context\="constructorbody_context" deleted\="false" description\="Code in created constructor stubs" enabled\="true" id\="org.eclipse.jdt.ui.text.codetemplates.constructorbody" name\="constructorbody">${body_statement}\n// ${todo} Auto-generated constructor stub</template><template autoinsert\="true" context\="getterbody_context" deleted\="false" description\="Code in created getters" enabled\="true" id\="org.eclipse.jdt.ui.text.codetemplates.getterbody" name\="getterbody">return ${field};</template><template autoinsert\="true" context\="setterbody_context" deleted\="false" description\="Code in created setters" enabled\="true" id\="org.eclipse.jdt.ui.text.codetemplates.setterbody" name\="setterbody">${field} \= ${param};</template></templates>

plugins/org.eclipse.elk.alg.vertiflex/META-INF/MANIFEST.MF

@@ -0,0 +1,14 @@
+Manifest-Version: 1.0
+Automatic-Module-Name: org.eclipse.elk.alg.vertiflex
+Bundle-ManifestVersion: 2
+Bundle-Name: VertiFlex Tree Layout Algorithm
+Bundle-SymbolicName: org.eclipse.elk.alg.vertiflex;singleton:=true
+Bundle-Version: 0.10.0.qualifier
+Bundle-Vendor: Eclipse Modeling Project
+Bundle-RequiredExecutionEnvironment: JavaSE-1.8
+Require-Bundle: com.google.guava,
+ org.eclipse.elk.alg.common,
+ org.eclipse.elk.core,
+ org.eclipse.elk.graph
+Export-Package: org.eclipse.elk.alg.vertiflex,
+ org.eclipse.elk.alg.vertiflex.options

plugins/org.eclipse.elk.alg.vertiflex/about.html

@@ -0,0 +1,36 @@
+<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
+    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
+<html xmlns="http://www.w3.org/1999/xhtml">
+<head>
+<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1" />
+<title>About</title>
+</head>
+<body lang="EN-US">
+	<h2>About This Content</h2>
+
+	<p>October 11, 2023</p>
+	<h3>License</h3>
+
+	<p>
+		The Eclipse Foundation makes available all content in this plug-in
+		(&quot;Content&quot;). Unless otherwise indicated below, the Content
+		is provided to you under the terms and conditions of the Eclipse
+		Public License Version 2.0 (&quot;EPL&quot;). A copy of the EPL is
+		available at <a href="http://www.eclipse.org/legal/epl-2.0">http://www.eclipse.org/legal/epl-2.0</a>.
+		For purposes of the EPL, &quot;Program&quot; will mean the Content.
+	</p>
+
+	<p>
+		If you did not receive this Content directly from the Eclipse
+		Foundation, the Content is being redistributed by another party
+		(&quot;Redistributor&quot;) and different terms and conditions may
+		apply to your use of any object code in the Content. Check the
+		Redistributor's license that was provided with the Content. If no such
+		license exists, contact the Redistributor. Unless otherwise indicated
+		below, the terms and conditions of the EPL still apply to any source
+		code in the Content and such source code may be obtained at <a
+			href="http://www.eclipse.org/">http://www.eclipse.org</a>.
+	</p>
+
+</body>
+</html>

plugins/org.eclipse.elk.alg.vertiflex/build.properties

@@ -0,0 +1,16 @@
+###############################################################################
+# Copyright (c) 2023 Kiel University and others.
+# 
+# This program and the accompanying materials are made available under the
+# terms of the Eclipse Public License 2.0 which is available at
+# http://www.eclipse.org/legal/epl-2.0.
+#
+# SPDX-License-Identifier: EPL-2.0
+###############################################################################
+source.. = src/,\
+           src-gen/
+output.. = bin/
+bin.includes = META-INF/,\
+               .,\
+               about.html
+src.includes = about.html

plugins/org.eclipse.elk.alg.vertiflex/pom.xml

@@ -0,0 +1,49 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+  Copyright (c) 2023 Kiel University and others.
+
+  This program and the accompanying materials are made available under the
+  terms of the Eclipse Public License 2.0 which is available at
+  http://www.eclipse.org/legal/epl-2.0.
+
+  SPDX-License-Identifier: EPL-2.0
+-->
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+  <parent>
+    <groupId>org.eclipse.elk</groupId>
+    <artifactId>parent</artifactId>
+    <version>0.10.0-SNAPSHOT</version>
+    <relativePath>../../build/pom.xml</relativePath>
+  </parent>
+
+  <groupId>org.eclipse.elk</groupId>
+  <artifactId>org.eclipse.elk.alg.vertiflex</artifactId>
+  <name>ELK Y Constraint Tree Layout Algorithm</name>
+  <version>0.10.0-SNAPSHOT</version>
+  <description>Tree drawing algorithm with y-level constraints.</description>
+  <packaging>eclipse-plugin</packaging>
+
+  <dependencies>
+    <dependency>
+      <groupId>org.eclipse.elk</groupId>
+      <artifactId>org.eclipse.elk.core</artifactId>
+      <version>0.10.0-SNAPSHOT</version>
+    </dependency>
+    <dependency>
+      <groupId>org.eclipse.elk</groupId>
+      <artifactId>org.eclipse.elk.alg.common</artifactId>
+      <version>0.10.0-SNAPSHOT</version>
+    </dependency>
+  </dependencies>
+
+  <build>
+    <plugins>
+      <!-- Generate code from .melk files. -->
+      <plugin>
+        <groupId>org.eclipse.xtext</groupId>
+        <artifactId>xtext-maven-plugin</artifactId>
+      </plugin>
+    </plugins>
+  </build>
+</project>

plugins/org.eclipse.elk.alg.vertiflex/src/META-INF/services/org.eclipse.elk.core.data.ILayoutMetaDataProvider

@@ -0,0 +1 @@
+org.eclipse.elk.alg.vertiflex.options.VertiFlexMetaDataProvider

plugins/org.eclipse.elk.alg.vertiflex/src/org/eclipse/elk/alg/vertiflex/EdgeRoutingStrategy.java

@@ -0,0 +1,28 @@
+/*******************************************************************************
+ * Copyright (c) 2023 Kiel University and others.
+ * 
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License 2.0 which is available at
+ * http://www.eclipse.org/legal/epl-2.0.
+ * 
+ * SPDX-License-Identifier: EPL-2.0 
+ *******************************************************************************/
+package org.eclipse.elk.alg.vertiflex;
+
+/**
+ * Strategies for routing edges in the tree layout.
+ *
+ */
+public enum EdgeRoutingStrategy {
+
+    /**
+     * Straight lines between nodes.
+     */
+    STRAIGHT,
+
+    /**
+     * Allow one bend point in edges to enable more compact layouts while also maintaining the node model order.
+     */
+    BEND
+
+}

plugins/org.eclipse.elk.alg.vertiflex/src/org/eclipse/elk/alg/vertiflex/InternalProperties.java

@@ -0,0 +1,69 @@
+/*******************************************************************************
+ * Copyright (c) 2023 Kiel University and others.
+ * 
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License 2.0 which is available at
+ * http://www.eclipse.org/legal/epl-2.0.
+ * 
+ * SPDX-License-Identifier: EPL-2.0 
+ *******************************************************************************/
+package org.eclipse.elk.alg.vertiflex;
+
+import org.eclipse.elk.alg.vertiflex.p2relative.OutlineNode;
+import org.eclipse.elk.graph.ElkNode;
+import org.eclipse.elk.graph.properties.IProperty;
+import org.eclipse.elk.graph.properties.Property;
+
+/**
+ * The internal properties of the tree layouter. Properties that are used internally
+ * but do not need to be public are stored here.
+ *
+ */
+public final class InternalProperties {
+
+    /**
+     * Private constructor to prevent initialization.
+     */
+    private InternalProperties() { }
+
+    /**
+     * Defines the left outline of this subtree.
+     */
+    public static final IProperty<OutlineNode> LEFT_OUTLINE = new Property<OutlineNode>("LEFT_OUTLINE");
+
+    /**
+     * Defines the right outline of this subtree.
+     */
+    public static final IProperty<OutlineNode> RIGHT_OUTLINE = new Property<OutlineNode>("RIGHT_OUTLINE");
+
+    /**
+     * Defines the maximum depth of outlines. This is the lowest point of the outline in the tree layout.
+     */
+    public static final IProperty<Double> OUTLINE_MAX_DEPTH = new Property<Double>("OUTLINE_MAX_DEPTH");
+
+    /** Defines the canvas of the tree. */
+    public static final IProperty<Double> MIN_X = new Property<Double>("MIN_X");
+
+    /** Defines the canvas of the tree. */
+    public static final IProperty<Double> MAX_X = new Property<Double>("MAX_X");
+
+    /** Defines the canvas of the tree. */
+    public static final IProperty<Double> MIN_Y = new Property<Double>("MIN_Y");
+
+    /** Defines the canvas of the tree. */
+    public static final IProperty<Double> MAX_Y = new Property<Double>("MAX_Y");
+
+    /** The root node of the graph. */
+    public static final IProperty<ElkNode> ROOT_NODE = new Property<ElkNode>("root");
+
+    /**
+     * Defines the bendpoint of an edge.  
+     */
+    public static final IProperty<Double> EDGE_BEND_HEIGHT = new Property<Double>("EDGE_BEND_HEIGHT");
+
+    /**
+     * Stores the model order of nodes. Smaller values come before larger values.
+     */
+    public static final IProperty<Integer> NODE_MODEL_ORDER = new Property<Integer>("Node Model Order");
+
+}

plugins/org.eclipse.elk.alg.vertiflex/src/org/eclipse/elk/alg/vertiflex/VertiFlex.melk

@@ -0,0 +1,80 @@
+/*******************************************************************************
+ * Copyright (c) 2023 Kiel University and others.
+ * 
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License 2.0 which is available at
+ * http://www.eclipse.org/legal/epl-2.0.
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ *******************************************************************************/
+package org.eclipse.elk.alg.vertiflex
+
+import org.eclipse.elk.alg.vertiflex.EdgeRoutingStrategy
+import org.eclipse.elk.alg.vertiflex.VertiFlexLayoutProvider
+import org.eclipse.elk.core.math.ElkPadding
+
+/**
+ * Declarations for the ELK VertiFlex tree layout algorithm.
+ */
+bundle {
+    metadataClass options.VertiFlexMetaDataProvider
+    idPrefix org.eclipse.elk.vertiflex
+}
+
+algorithm vertiflex(VertiFlexLayoutProvider) {
+    label "ELK VertiFlex"
+    description
+        "Tree layout algorithm that allows defining set vertical positions for nodes
+         rather than automatically placing nodes on levels according to their topology."
+    metadataClass options.VertiFlexOptions
+    category org.eclipse.elk.tree
+    features multi_edges, edge_labels
+    supports org.eclipse.elk.spacing.nodeNode = 20
+    supports org.eclipse.elk.padding = new ElkPadding(5)
+    supports org.eclipse.elk.interactive
+    supports org.eclipse.elk.portConstraints
+    supports org.eclipse.elk.edgeLabels.inline = false
+    // Common node micro layout
+    supports org.eclipse.elk.omitNodeMicroLayout
+    supports org.eclipse.elk.margins
+    // Algorithm specific properties
+    supports verticalConstraint
+    supports layoutStrategy
+    supports layerDistance
+    supports considerNodeModelOrder
+
+}
+
+option verticalConstraint: double {
+    label "Fixed vertical position"
+    description
+        "The Y position that the node should be fixed at."
+    targets nodes
+}
+
+option layoutStrategy: EdgeRoutingStrategy {
+    label "Edge layout strategy"
+    description
+        "Strategy for the layout of the children. 'straight' for straight line drawings, 'bend' for a possible bend.
+         When straight edges are prioritized the nodes will be reordered in order to guarantee that straight edges are
+         possible. If bend points are enabled on the other hand, the given model order of the nodes is maintained and 
+         bend points are introduced to prevent edge node overlaps."
+    targets nodes
+    default = EdgeRoutingStrategy.STRAIGHT
+}
+
+option layerDistance: double {
+    label "Layer distance"
+    description
+        "The distance to use between nodes of different layers if no vertical constraints are set."
+    targets parents
+    default = 50.0
+}
+
+option considerNodeModelOrder: boolean {
+    label "Consider node model order"
+    description
+        "Consider node model as a secondary criterion when using straight line routing."
+    targets parents
+    default = true
+}