Improve theme support

src/net/sourceforge/plantuml/AbstractPSystem.java

@@ -53,6 +53,7 @@ import net.sourceforge.plantuml.graphic.HorizontalAlignment;
 import net.sourceforge.plantuml.graphic.VerticalAlignment;
 import net.sourceforge.plantuml.stats.StatsUtilsIncrement;
 import net.sourceforge.plantuml.style.ClockwiseTopRightBottomLeft;
+import net.sourceforge.plantuml.style.StyleBuilder;
 import net.sourceforge.plantuml.ugraphic.ImageBuilder;
 import net.sourceforge.plantuml.ugraphic.color.NoSuchColorException;
 import net.sourceforge.plantuml.version.License;
@@ -146,6 +147,13 @@ public abstract class AbstractPSystem implements Diagram {
 			throws IOException {
 		final long now = System.currentTimeMillis();
 		try {
+//			if (this instanceof TitledDiagram) {
+//				final TitledDiagram titledDiagram = (TitledDiagram) this;
+//				final StyleBuilder styleBuilder = titledDiagram.getCurrentStyleBuilder();
+//				if (styleBuilder != null) {
+//					styleBuilder.printMe();
+//				}
+//			}
 			return exportDiagramNow(os, index, fileFormatOption);
 		} finally {
 			if (OptionFlags.getInstance().isEnableStats()) {
@@ -168,8 +176,8 @@ public abstract class AbstractPSystem implements Diagram {
 	}
 
 	// TODO "index" isnt really being used
-	protected abstract ImageData exportDiagramNow(OutputStream os, int index, FileFormatOption fileFormatOption
+	protected abstract ImageData exportDiagramNow(OutputStream os, int index, FileFormatOption fileFormatOption)
-			) throws IOException;
+			throws IOException;
 
 	public ClockwiseTopRightBottomLeft getDefaultMargins() {
 		return ClockwiseTopRightBottomLeft.same(0);

src/net/sourceforge/plantuml/Option.java

@@ -223,6 +223,12 @@ public class Option {
 				this.failfast2 = true;
 			} else if (s.equalsIgnoreCase("-checkonly")) {
 				this.checkOnly = true;
+			} else if (s.equalsIgnoreCase("-theme")) {
+				i++;
+				if (i == arg.length) {
+					continue;
+				}
+				this.config.add(0, "!theme " + arg[i]);
 			} else if (s.equalsIgnoreCase("-config")) {
 				i++;
 				if (i == arg.length) {

src/net/sourceforge/plantuml/OptionPrint.java

@@ -108,6 +108,7 @@ public class OptionPrint {
 				+ "file\tTo include file as if '!include file' were used");
 		System.out.println(
 				"    -I" + separator + "path" + separator + "to" + separator + "*.puml\tTo include files with pattern");
+		System.out.println("    -theme xxx\\t\\tTo use a specific theme");
 		System.out.println("    -charset xxx\tTo use a specific charset (default is " + charset + ")");
 		System.out.println("    -e[x]clude pattern\tTo exclude files that match the provided pattern");
 		System.out.println("    -metadata\t\tTo retrieve PlantUML sources from PNG images");

src/net/sourceforge/plantuml/creole/legacy/AtomText.java

@@ -59,6 +59,7 @@ import net.sourceforge.plantuml.ugraphic.UText;
 import net.sourceforge.plantuml.ugraphic.UTranslate;
 import net.sourceforge.plantuml.ugraphic.color.HColor;
 import net.sourceforge.plantuml.ugraphic.color.HColorAutomatic;
+import net.sourceforge.plantuml.ugraphic.color.HColorAutomaticLegacy;
 import net.sourceforge.plantuml.ugraphic.color.HColorSimple;
 import net.sourceforge.plantuml.utils.CharHidder;
 
@@ -144,10 +145,15 @@ public final class AtomText extends AbstractAtom implements Atom {
 			}
 			HColor textColor = fontConfiguration.getColor();
 			FontConfiguration useFontConfiguration = fontConfiguration;
-			if (textColor instanceof HColorAutomatic && ug.getParam().getBackcolor() != null) {
+			if (textColor instanceof HColorAutomaticLegacy && ug.getParam().getBackcolor() != null) {
 				textColor = ((HColorSimple) ug.getParam().getBackcolor()).opposite();
 				useFontConfiguration = fontConfiguration.changeColor(textColor);
 			}
+			if (textColor instanceof HColorAutomatic) {
+				final HColor backcolor = ug.getParam().getBackcolor();
+				textColor = ((HColorAutomatic) textColor).getAppropriateColor(backcolor);
+				useFontConfiguration = fontConfiguration.changeColor(textColor);
+			}
 			if (marginLeft != AtomTextUtils.ZERO) {
 				ug = ug.apply(UTranslate.dx(marginLeft.getDouble(ug.getStringBounder())));
 			}

src/net/sourceforge/plantuml/sequencediagram/graphic/SequenceDiagramFileMakerPuma2.java

@@ -67,6 +67,7 @@ import net.sourceforge.plantuml.skin.rose.Rose;
 import net.sourceforge.plantuml.style.SName;
 import net.sourceforge.plantuml.style.Style;
 import net.sourceforge.plantuml.style.StyleSignature;
+import net.sourceforge.plantuml.ugraphic.ImageBuilder;
 import net.sourceforge.plantuml.ugraphic.UGraphic;
 import net.sourceforge.plantuml.ugraphic.UTranslate;
 import net.sourceforge.plantuml.ugraphic.color.HColor;
@@ -196,7 +197,8 @@ public class SequenceDiagramFileMakerPuma2 implements FileMaker {
 				}
 
 				if (compTitle != null) {
-					compTitle.drawU(ug.apply(new UTranslate(area.getTitleX(), area.getTitleY())));
+					final HColor back = ImageBuilder.calculateBackColor(diagram);
+					compTitle.drawU(ug.apply(back.bg()).apply(new UTranslate(area.getTitleX(), area.getTitleY())));
 				}
 				caption.drawU(ug.apply(new UTranslate(area.getCaptionX(), area.getCaptionY())));
 
@@ -218,9 +220,7 @@ public class SequenceDiagramFileMakerPuma2 implements FileMaker {
 			}
 
 		};
-		return diagram.createImageBuilder(fileFormatOption)
+		return diagram.createImageBuilder(fileFormatOption).drawable(drawable).write(os);
-				.drawable(drawable)
-				.write(os);
 	}
 
 	private void drawFooter(SequenceDiagramArea area, UGraphic ug, int page) {

src/net/sourceforge/plantuml/style/Style.java

@@ -67,6 +67,19 @@ public class Style {
 		this.signature = signature;
 	}
 
+	public void printMe() {
+		if (map.size() == 0) {
+			return;
+		}
+		System.err.println(signature + " {");
+		for (Entry<PName, Value> ent : map.entrySet()) {
+			System.err.println("  " + ent.getKey() + ": " + ent.getValue().asString());
+
+		}
+		System.err.println("}");
+
+	}
+
 	@Override
 	public String toString() {
 		return signature + " " + map;

src/net/sourceforge/plantuml/style/StyleBuilder.java

@@ -52,6 +52,12 @@ public class StyleBuilder implements AutomaticCounter {
 	private final SkinParam skinParam;
 	private int counter;
 
+	public void printMe() {
+		for (Entry<StyleSignature, Style> ent : styles.entrySet()) {
+			ent.getValue().printMe();
+		}
+	}
+
 	private StyleBuilder(SkinParam skinParam, Set<StyleSignature> printedForLog) {
 		this.skinParam = skinParam;
 		this.printedForLog = new LinkedHashSet<StyleSignature>();

src/net/sourceforge/plantuml/style/StyleSignature.java

@@ -38,7 +38,6 @@ package net.sourceforge.plantuml.style;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Collections;
-import java.util.HashSet;
 import java.util.LinkedHashSet;
 import java.util.List;
 import java.util.Set;
@@ -72,7 +71,7 @@ public class StyleSignature {
 		if (url == null) {
 			return this;
 		}
-		final Set<String> result = new HashSet<String>(names);
+		final Set<String> result = new LinkedHashSet<String>(names);
 		result.add(SName.clickable.name());
 		return new StyleSignature(result);
 
@@ -85,7 +84,7 @@ public class StyleSignature {
 		if (s.contains("*") || s.contains("&") || s.contains("-")) {
 			throw new IllegalArgumentException();
 		}
-		final Set<String> result = new HashSet<String>(names);
+		final Set<String> result = new LinkedHashSet<String>(names);
 		result.add(clean(s));
 		return new StyleSignature(result);
 	}
@@ -95,7 +94,7 @@ public class StyleSignature {
 	}
 
 	public StyleSignature addStar() {
-		final Set<String> result = new HashSet<String>(names);
+		final Set<String> result = new LinkedHashSet<String>(names);
 		result.add("*");
 		return new StyleSignature(result);
 	}

src/net/sourceforge/plantuml/syntax/LanguageDescriptor.java

@@ -184,6 +184,7 @@ public class LanguageDescriptor {
 
 		preproc.add("!exit");
 		preproc.add("!include");
+		preproc.add("!theme");
 		preproc.add("!pragma");
 		preproc.add("!define");
 		preproc.add("!undef");

src/net/sourceforge/plantuml/tim/TContext.java

@@ -82,8 +82,10 @@ import net.sourceforge.plantuml.tim.iterator.CodeIteratorWhile;
 import net.sourceforge.plantuml.tim.stdlib.AlwaysFalse;
 import net.sourceforge.plantuml.tim.stdlib.AlwaysTrue;
 import net.sourceforge.plantuml.tim.stdlib.CallUserFunction;
+import net.sourceforge.plantuml.tim.stdlib.Darken;
 import net.sourceforge.plantuml.tim.stdlib.DateFunction;
 import net.sourceforge.plantuml.tim.stdlib.Dirpath;
+import net.sourceforge.plantuml.tim.stdlib.Feature;
 import net.sourceforge.plantuml.tim.stdlib.FileExists;
 import net.sourceforge.plantuml.tim.stdlib.Filename;
 import net.sourceforge.plantuml.tim.stdlib.FunctionExists;
@@ -92,6 +94,9 @@ import net.sourceforge.plantuml.tim.stdlib.GetVersion;
 import net.sourceforge.plantuml.tim.stdlib.Getenv;
 import net.sourceforge.plantuml.tim.stdlib.IntVal;
 import net.sourceforge.plantuml.tim.stdlib.InvokeProcedure;
+import net.sourceforge.plantuml.tim.stdlib.IsDark;
+import net.sourceforge.plantuml.tim.stdlib.IsLight;
+import net.sourceforge.plantuml.tim.stdlib.Lighten;
 import net.sourceforge.plantuml.tim.stdlib.LogicalNot;
 import net.sourceforge.plantuml.tim.stdlib.Lower;
 import net.sourceforge.plantuml.tim.stdlib.Newline;
@@ -149,15 +154,20 @@ public class TContext {
 		functionsSet.addFunction(new Lower());
 		functionsSet.addFunction(new StringFunction());
 		functionsSet.addFunction(new Newline());
+		functionsSet.addFunction(new Feature());
+		functionsSet.addFunction(new Lighten());
+		functionsSet.addFunction(new Darken());
+		functionsSet.addFunction(new IsDark());
+		functionsSet.addFunction(new IsLight());
+		// %standard_exists_function
+		// %str_replace
 		// !exit
 		// !log
 		// %min
 		// %max
 		// Regexp
-		// %plantuml_version
 		// %time
 		// %trim
-		// %str_replace
 	}
 
 	public TContext(ImportedFiles importedFiles, Defines defines, String charset,

src/net/sourceforge/plantuml/tim/stdlib/Darken.java

@@ -0,0 +1,75 @@
+/* ========================================================================
+ * PlantUML : a free UML diagram generator
+ * ========================================================================
+ *
+ * (C) Copyright 2009-2020, Arnaud Roques
+ *
+ * Project Info:  http://plantuml.com
+ *
+ * If you like this project or if you find it useful, you can support us at:
+ *
+ * http://plantuml.com/patreon (only 1$ per month!)
+ * http://plantuml.com/paypal
+ *
+ * This file is part of PlantUML.
+ *
+ * PlantUML is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * PlantUML 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 for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
+ * USA.
+ *
+ *
+ * Original Author:  Arnaud Roques
+ *
+ */
+package net.sourceforge.plantuml.tim.stdlib;
+
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+
+import net.sourceforge.plantuml.LineLocation;
+import net.sourceforge.plantuml.tim.EaterException;
+import net.sourceforge.plantuml.tim.EaterExceptionLocated;
+import net.sourceforge.plantuml.tim.TContext;
+import net.sourceforge.plantuml.tim.TFunctionSignature;
+import net.sourceforge.plantuml.tim.TMemory;
+import net.sourceforge.plantuml.tim.expression.TValue;
+import net.sourceforge.plantuml.ugraphic.color.HColor;
+import net.sourceforge.plantuml.ugraphic.color.HColorSet;
+import net.sourceforge.plantuml.ugraphic.color.NoSuchColorException;
+
+public class Darken extends SimpleReturnFunction {
+
+	// Inspired from https://github.com/Qix-/color
+	public TFunctionSignature getSignature() {
+		return new TFunctionSignature("%darken", 2);
+	}
+
+	public boolean canCover(int nbArg, Set<String> namedArgument) {
+		return nbArg == 2;
+	}
+
+	public TValue executeReturnFunction(TContext context, TMemory memory, LineLocation location, List<TValue> values,
+			Map<String, TValue> named) throws EaterException, EaterExceptionLocated {
+		final String colorString = values.get(0).toString();
+		final int ratio = values.get(1).toInt();
+		try {
+			HColor color = HColorSet.instance().getColor(colorString);
+			color = color.darken(ratio);
+			return TValue.fromString(color.asString());
+		} catch (NoSuchColorException e) {
+			throw EaterException.located("No such color");
+		}
+	}
+}

src/net/sourceforge/plantuml/tim/stdlib/Feature.java

@@ -0,0 +1,70 @@
+/* ========================================================================
+ * PlantUML : a free UML diagram generator
+ * ========================================================================
+ *
+ * (C) Copyright 2009-2020, Arnaud Roques
+ *
+ * Project Info:  http://plantuml.com
+ *
+ * If you like this project or if you find it useful, you can support us at:
+ *
+ * http://plantuml.com/patreon (only 1$ per month!)
+ * http://plantuml.com/paypal
+ *
+ * This file is part of PlantUML.
+ *
+ * PlantUML is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * PlantUML 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 for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
+ * USA.
+ *
+ *
+ * Original Author:  Arnaud Roques
+ *
+ */
+package net.sourceforge.plantuml.tim.stdlib;
+
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+
+import net.sourceforge.plantuml.LineLocation;
+import net.sourceforge.plantuml.tim.EaterException;
+import net.sourceforge.plantuml.tim.EaterExceptionLocated;
+import net.sourceforge.plantuml.tim.TContext;
+import net.sourceforge.plantuml.tim.TFunctionSignature;
+import net.sourceforge.plantuml.tim.TMemory;
+import net.sourceforge.plantuml.tim.expression.TValue;
+
+public class Feature extends SimpleReturnFunction {
+
+	public TFunctionSignature getSignature() {
+		return new TFunctionSignature("%feature", 1);
+	}
+
+	public boolean canCover(int nbArg, Set<String> namedArgument) {
+		return nbArg == 1;
+	}
+
+	public TValue executeReturnFunction(TContext context, TMemory memory, LineLocation location, List<TValue> values,
+			Map<String, TValue> named) throws EaterException, EaterExceptionLocated {
+		final String arg = values.get(0).toString();
+		if ("style".equalsIgnoreCase(arg)) {
+			return TValue.fromInt(1);
+		}
+		if ("theme".equalsIgnoreCase(arg)) {
+			return TValue.fromInt(1);
+		}
+		return TValue.fromInt(0);
+	}
+}

src/net/sourceforge/plantuml/tim/stdlib/IsDark.java

@@ -0,0 +1,73 @@
+/* ========================================================================
+ * PlantUML : a free UML diagram generator
+ * ========================================================================
+ *
+ * (C) Copyright 2009-2020, Arnaud Roques
+ *
+ * Project Info:  http://plantuml.com
+ *
+ * If you like this project or if you find it useful, you can support us at:
+ *
+ * http://plantuml.com/patreon (only 1$ per month!)
+ * http://plantuml.com/paypal
+ *
+ * This file is part of PlantUML.
+ *
+ * PlantUML is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * PlantUML 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 for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
+ * USA.
+ *
+ *
+ * Original Author:  Arnaud Roques
+ *
+ */
+package net.sourceforge.plantuml.tim.stdlib;
+
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+
+import net.sourceforge.plantuml.LineLocation;
+import net.sourceforge.plantuml.tim.EaterException;
+import net.sourceforge.plantuml.tim.EaterExceptionLocated;
+import net.sourceforge.plantuml.tim.TContext;
+import net.sourceforge.plantuml.tim.TFunctionSignature;
+import net.sourceforge.plantuml.tim.TMemory;
+import net.sourceforge.plantuml.tim.expression.TValue;
+import net.sourceforge.plantuml.ugraphic.color.HColor;
+import net.sourceforge.plantuml.ugraphic.color.HColorSet;
+import net.sourceforge.plantuml.ugraphic.color.NoSuchColorException;
+
+public class IsDark extends SimpleReturnFunction {
+
+	// Inspired from https://github.com/Qix-/color
+	public TFunctionSignature getSignature() {
+		return new TFunctionSignature("%is_dark", 1);
+	}
+
+	public boolean canCover(int nbArg, Set<String> namedArgument) {
+		return nbArg == 1;
+	}
+
+	public TValue executeReturnFunction(TContext context, TMemory memory, LineLocation location, List<TValue> values,
+			Map<String, TValue> named) throws EaterException, EaterExceptionLocated {
+		final String colorString = values.get(0).toString();
+		try {
+			final HColor color = HColorSet.instance().getColor(colorString);
+			return TValue.fromBoolean(color.isDark());
+		} catch (NoSuchColorException e) {
+			throw EaterException.located("No such color");
+		}
+	}
+}

src/net/sourceforge/plantuml/tim/stdlib/IsLight.java

@@ -0,0 +1,73 @@
+/* ========================================================================
+ * PlantUML : a free UML diagram generator
+ * ========================================================================
+ *
+ * (C) Copyright 2009-2020, Arnaud Roques
+ *
+ * Project Info:  http://plantuml.com
+ *
+ * If you like this project or if you find it useful, you can support us at:
+ *
+ * http://plantuml.com/patreon (only 1$ per month!)
+ * http://plantuml.com/paypal
+ *
+ * This file is part of PlantUML.
+ *
+ * PlantUML is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * PlantUML 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 for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
+ * USA.
+ *
+ *
+ * Original Author:  Arnaud Roques
+ *
+ */
+package net.sourceforge.plantuml.tim.stdlib;
+
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+
+import net.sourceforge.plantuml.LineLocation;
+import net.sourceforge.plantuml.tim.EaterException;
+import net.sourceforge.plantuml.tim.EaterExceptionLocated;
+import net.sourceforge.plantuml.tim.TContext;
+import net.sourceforge.plantuml.tim.TFunctionSignature;
+import net.sourceforge.plantuml.tim.TMemory;
+import net.sourceforge.plantuml.tim.expression.TValue;
+import net.sourceforge.plantuml.ugraphic.color.HColor;
+import net.sourceforge.plantuml.ugraphic.color.HColorSet;
+import net.sourceforge.plantuml.ugraphic.color.NoSuchColorException;
+
+public class IsLight extends SimpleReturnFunction {
+
+	// Inspired from https://github.com/Qix-/color
+	public TFunctionSignature getSignature() {
+		return new TFunctionSignature("%is_light", 1);
+	}
+
+	public boolean canCover(int nbArg, Set<String> namedArgument) {
+		return nbArg == 1;
+	}
+
+	public TValue executeReturnFunction(TContext context, TMemory memory, LineLocation location, List<TValue> values,
+			Map<String, TValue> named) throws EaterException, EaterExceptionLocated {
+		final String colorString = values.get(0).toString();
+		try {
+			final HColor color = HColorSet.instance().getColor(colorString);
+			return TValue.fromBoolean(!color.isDark());
+		} catch (NoSuchColorException e) {
+			throw EaterException.located("No such color");
+		}
+	}
+}

src/net/sourceforge/plantuml/tim/stdlib/Lighten.java

@@ -0,0 +1,75 @@
+/* ========================================================================
+ * PlantUML : a free UML diagram generator
+ * ========================================================================
+ *
+ * (C) Copyright 2009-2020, Arnaud Roques
+ *
+ * Project Info:  http://plantuml.com
+ *
+ * If you like this project or if you find it useful, you can support us at:
+ *
+ * http://plantuml.com/patreon (only 1$ per month!)
+ * http://plantuml.com/paypal
+ *
+ * This file is part of PlantUML.
+ *
+ * PlantUML is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * PlantUML 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 for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
+ * USA.
+ *
+ *
+ * Original Author:  Arnaud Roques
+ *
+ */
+package net.sourceforge.plantuml.tim.stdlib;
+
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+
+import net.sourceforge.plantuml.LineLocation;
+import net.sourceforge.plantuml.tim.EaterException;
+import net.sourceforge.plantuml.tim.EaterExceptionLocated;
+import net.sourceforge.plantuml.tim.TContext;
+import net.sourceforge.plantuml.tim.TFunctionSignature;
+import net.sourceforge.plantuml.tim.TMemory;
+import net.sourceforge.plantuml.tim.expression.TValue;
+import net.sourceforge.plantuml.ugraphic.color.HColor;
+import net.sourceforge.plantuml.ugraphic.color.HColorSet;
+import net.sourceforge.plantuml.ugraphic.color.NoSuchColorException;
+
+public class Lighten extends SimpleReturnFunction {
+
+	// Inspired from https://github.com/Qix-/color
+	public TFunctionSignature getSignature() {
+		return new TFunctionSignature("%lighten", 2);
+	}
+
+	public boolean canCover(int nbArg, Set<String> namedArgument) {
+		return nbArg == 2;
+	}
+
+	public TValue executeReturnFunction(TContext context, TMemory memory, LineLocation location, List<TValue> values,
+			Map<String, TValue> named) throws EaterException, EaterExceptionLocated {
+		final String colorString = values.get(0).toString();
+		final int ratio = values.get(1).toInt();
+		try {
+			HColor color = HColorSet.instance().getColor(colorString);
+			color = color.lighten(ratio);
+			return TValue.fromString(color.asString());
+		} catch (NoSuchColorException e) {
+			throw EaterException.located("No such color");
+		}
+	}
+}

src/net/sourceforge/plantuml/ugraphic/FontChecker.java

@@ -35,6 +35,8 @@
  */
 package net.sourceforge.plantuml.ugraphic;
 
+import static net.sourceforge.plantuml.ugraphic.ImageBuilder.plainPngBuilder;
+
 import java.awt.Font;
 import java.awt.GraphicsEnvironment;
 import java.awt.Shape;
@@ -61,8 +63,6 @@ import net.sourceforge.plantuml.svg.LengthAdjust;
 import net.sourceforge.plantuml.svg.SvgGraphics;
 import net.sourceforge.plantuml.ugraphic.color.HColorUtils;
 
-import static net.sourceforge.plantuml.ugraphic.ImageBuilder.plainPngBuilder;
-
 public class FontChecker {
 
 	final private UFont font;

src/net/sourceforge/plantuml/ugraphic/ImageBuilder.java

@@ -35,6 +35,8 @@
  */
 package net.sourceforge.plantuml.ugraphic;
 
+import static net.sourceforge.plantuml.SkinParam.DEFAULT_PRESERVE_ASPECT_RATIO;
+
 import java.awt.Color;
 import java.awt.Graphics2D;
 import java.awt.Image;
@@ -105,8 +107,6 @@ import net.sourceforge.plantuml.ugraphic.tikz.UGraphicTikz;
 import net.sourceforge.plantuml.ugraphic.txt.UGraphicTxt;
 import net.sourceforge.plantuml.ugraphic.visio.UGraphicVdx;
 
-import static net.sourceforge.plantuml.SkinParam.DEFAULT_PRESERVE_ASPECT_RATIO;
-
 public class ImageBuilder {
 
 	private Animation animation;
@@ -484,7 +484,7 @@ public class ImageBuilder {
 		return ug;
 	}
 
-	private static HColor calculateBackColor(TitledDiagram diagram) {
+	public static HColor calculateBackColor(TitledDiagram diagram) {
 		if (UseStyle.useBetaStyle()) {
 			final Style style = StyleSignature
 					.of(SName.root, SName.document, diagram.getUmlDiagramType().getStyleName())

src/net/sourceforge/plantuml/ugraphic/PixelImage.java

@@ -40,7 +40,7 @@ import java.awt.geom.AffineTransform;
 import java.awt.image.AffineTransformOp;
 import java.awt.image.BufferedImage;
 
-import net.sourceforge.plantuml.ugraphic.color.ColorChangerMonochrome;
+import net.sourceforge.plantuml.ugraphic.color.ColorUtils;
 
 public class PixelImage implements MutableImage {
 
@@ -131,8 +131,8 @@ public class PixelImage implements MutableImage {
 				// if (isTransparent(color)) {
 				// continue;
 				// }
-				final int grey = ColorChangerMonochrome.getGrayScale(rgb);
+				final int grey = ColorUtils.getGrayScale(rgb);
-				if (darkerRgb == -1 || grey < ColorChangerMonochrome.getGrayScale(darkerRgb)) {
+				if (darkerRgb == -1 || grey < ColorUtils.getGrayScale(darkerRgb)) {
 					darkerRgb = rgb;
 				}
 			}

src/net/sourceforge/plantuml/ugraphic/color/ColorChangerMonochrome.java

@@ -43,21 +43,8 @@ public class ColorChangerMonochrome {
 		if (color == null) {
 			return null;
 		}
-		final int grayScale = getGrayScale(color);
+		final int grayScale = ColorUtils.getGrayScale(color);
 		return new Color(grayScale, grayScale, grayScale);
 	}
 
-	private static int getGrayScale(Color color) {
-		final int red = color.getRed();
-		final int green = color.getGreen();
-		final int blue = color.getBlue();
-		return (int) (red * .3 + green * .59 + blue * .11);
-	}
-
-	public static int getGrayScale(int rgb) {
-		final int red = rgb & 0x00FF0000;
-		final int green = (rgb & 0x0000FF00) >> 8;
-		final int blue = (rgb & 0x000000FF) >> 16;
-		return (int) (red * .3 + green * .59 + blue * .11);
-	}
 }

src/net/sourceforge/plantuml/ugraphic/color/ColorMapperIdentity.java

@@ -52,6 +52,9 @@ public class ColorMapperIdentity extends AbstractColorMapper implements ColorMap
 		if (color instanceof HColorMiddle) {
 			return ((HColorMiddle) color).getMappedColor(this);
 		}
+		if (color instanceof HColorAutomatic) {
+			throw new IllegalStateException();
+		}
 		return ((HColorSimple) color).getColor999();
 	}
 }

src/net/sourceforge/plantuml/ugraphic/color/ColorUtils.java

@@ -39,11 +39,23 @@ import java.awt.Color;
 
 public class ColorUtils {
 
-	static int getGrayScale(Color color) {
+	public static int getGrayScale(Color color) {
-		final int grayScale = (int) (color.getRed() * .3 + color.getGreen() * .59 + color.getBlue() * .11);
+		return getGrayScale(color.getRed(), color.getGreen(), color.getBlue());
+	}
+
+	public static int getGrayScale(int red, int green, int blue) {
+		// YIQ equation from http://24ways.org/2010/calculating-color-contrast
+		final int grayScale = (red * 299 + green * 587 + blue * 114) / 1000;
 		return grayScale;
 	}
 
+	public static int getGrayScale(int rgb) {
+		final int red = (rgb & 0x00FF0000) >> 16;
+		final int green = (rgb & 0x0000FF00) >> 8;
+		final int blue = (rgb & 0x000000FF);
+		return getGrayScale(red, green, blue);
+	}
+
 	public static Color getGrayScaleColor(Color color) {
 		final int grayScale = getGrayScale(color);
 		return new Color(grayScale, grayScale, grayScale);

src/net/sourceforge/plantuml/ugraphic/color/HColor.java

@@ -42,4 +42,12 @@ public interface HColor extends UChange {
 
 	public UBackground bg();
 
+	public HColor darken(int ratio);
+
+	public HColor lighten(int ratio);
+
+	public String asString();
+
+	public boolean isDark();
+
 }

src/net/sourceforge/plantuml/ugraphic/color/HColorAbstract.java

@@ -38,7 +38,7 @@ import net.sourceforge.plantuml.ugraphic.UBackground;
 
 abstract class HColorAbstract implements HColor {
 
-	final public UBackground bg() {
+	public UBackground bg() {
 		return new UBackground() {
 			public HColor getBackColor() {
 				return HColorAbstract.this;
@@ -46,4 +46,21 @@ abstract class HColorAbstract implements HColor {
 		};
 	}
 
+	public HColor lighten(int ratio) {
+		return this;
+	}
+
+	public HColor darken(int ratio) {
+		return this;
+	}
+	
+	@Override
+	public boolean isDark() {
+		return true;
+	}
+
+	public String asString() {
+		return "?" + getClass().getSimpleName();
+	}
+
 }

src/net/sourceforge/plantuml/ugraphic/color/HColorAutomatic.java

@@ -36,4 +36,22 @@ package net.sourceforge.plantuml.ugraphic.color;
 
 public class HColorAutomatic extends HColorAbstract implements HColor {
 
+	private final HColor color1;
+	private final HColor color2;
+
+	public HColorAutomatic(HColor color1, HColor color2) {
+		this.color1 = color1;
+		this.color2 = color2;
+	}
+
+	public HColor getAppropriateColor(HColor back) {
+		if (back == null) {
+			return color2;
+		}
+		if (back.isDark()) {
+			return color2;
+		}
+		return color1;
+	}
+
 }

src/net/sourceforge/plantuml/ugraphic/color/HColorAutomaticLegacy.java

@@ -0,0 +1,39 @@
+/* ========================================================================
+ * PlantUML : a free UML diagram generator
+ * ========================================================================
+ *
+ * (C) Copyright 2009-2020, Arnaud Roques
+ *
+ * Project Info:  http://plantuml.com
+ * 
+ * If you like this project or if you find it useful, you can support us at:
+ * 
+ * http://plantuml.com/patreon (only 1$ per month!)
+ * http://plantuml.com/paypal
+ * 
+ * This file is part of PlantUML.
+ *
+ * PlantUML is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * PlantUML 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 for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
+ * USA.
+ *
+ *
+ * Original Author:  Arnaud Roques
+ *
+ */
+package net.sourceforge.plantuml.ugraphic.color;
+
+public class HColorAutomaticLegacy extends HColorAbstract implements HColor {
+
+}

src/net/sourceforge/plantuml/ugraphic/color/HColorNone.java

@@ -36,8 +36,9 @@ package net.sourceforge.plantuml.ugraphic.color;
 
 import net.sourceforge.plantuml.ugraphic.UBackground;
 
-public class HColorNone implements HColor {
+public class HColorNone extends HColorAbstract implements HColor {
 
+	@Override
 	public UBackground bg() {
 		return new UBackground() {
 			public HColor getBackColor() {

src/net/sourceforge/plantuml/ugraphic/color/HColorSet.java

@@ -238,17 +238,36 @@ public class HColorSet {
 			this.s2 = s2;
 		}
 
-		boolean isGradientValid() {
+		boolean isValid() {
 			return isColorValid(s1) && isColorValid(s2);
 		}
 
-		HColorGradient buildGradient(HColor background) {
+		HColorGradient buildInternal(HColor background) {
 			return new HColorGradient(build(s1, background), build(s2, background), sep);
 		}
 
 	}
 
-	private Gradient fromString(String s) {
+	class Automatic {
+		private final String s1;
+		private final String s2;
+
+		Automatic(String s1, String s2) {
+			this.s1 = s1;
+			this.s2 = s2;
+		}
+
+		boolean isValid() {
+			return isColorValid(s1) && isColorValid(s2);
+		}
+
+		HColorAutomatic buildInternal(HColor background) {
+			return new HColorAutomatic(build(s1, background), build(s2, background));
+		}
+
+	}
+
+	private Gradient gradientFromString(String s) {
 		final Matcher2 m = MyPattern.cmpile("[-\\\\|/]").matcher(s);
 		if (m.find()) {
 			final char sep = m.group(0).charAt(0);
@@ -260,6 +279,22 @@ public class HColorSet {
 		return null;
 	}
 
+	private Automatic automaticFromString(String s) {
+		if (s.startsWith("#")) {
+			s = s.substring(1);
+		}
+		if (s.startsWith("?") == false) {
+			return null;
+		}
+		final int idx = s.indexOf(':');
+		if (idx != -1) {
+			final String s1 = s.substring(1, idx);
+			final String s2 = s.substring(idx + 1);
+			return new Automatic(s1, s2);
+		}
+		return null;
+	}
+
 	public HColor getColorOrWhite(String s) {
 		return getColorOrWhite(s, null);
 	}
@@ -290,9 +325,13 @@ public class HColorSet {
 		if (isColorValid(s) == false) {
 			throw new NoSuchColorException();
 		}
-		final Gradient gradient = fromString(s);
+		final Automatic automatic = automaticFromString(s);
+		if (automatic != null) {
+			return automatic.buildInternal(background);
+		}
+		final Gradient gradient = gradientFromString(s);
 		if (gradient != null) {
-			return gradient.buildGradient(background);
+			return gradient.buildInternal(background);
 		}
 		if (background == null && (s.equalsIgnoreCase("#transparent") || s.equalsIgnoreCase("transparent")))
 			s = "#00000000";
@@ -301,9 +340,13 @@ public class HColorSet {
 
 	private boolean isColorValid(String s) {
 		s = removeFirstDieseAndgoLowerCase(s);
-		final Gradient gradient = fromString(s);
+		final Automatic automatic = automaticFromString(s);
+		if (automatic != null) {
+			return automatic.isValid();
+		}
+		final Gradient gradient = gradientFromString(s);
 		if (gradient != null) {
-			return gradient.isGradientValid();
+			return gradient.isValid();
 		}
 		if (s.matches("[0-9A-Fa-f]{3}")) {
 			return true;
@@ -333,7 +376,7 @@ public class HColorSet {
 		if (s.equalsIgnoreCase("transparent") || s.equalsIgnoreCase("background")) {
 			return new HColorBackground(background);
 		} else if (s.equalsIgnoreCase("automatic")) {
-			return new HColorAutomatic();
+			return new HColorAutomaticLegacy();
 		} else if (s.matches("[0-9A-Fa-f]{3}")) {
 			s = "" + s.charAt(0) + s.charAt(0) + s.charAt(1) + s.charAt(1) + s.charAt(2) + s.charAt(2);
 			color = new Color(Integer.parseInt(s, 16));

src/net/sourceforge/plantuml/ugraphic/color/HColorSimple.java

@@ -37,6 +37,8 @@ package net.sourceforge.plantuml.ugraphic.color;
 
 import java.awt.Color;
 
+import net.sourceforge.plantuml.svek.DotStringFactory;
+
 public class HColorSimple extends HColorAbstract implements HColor {
 
 	private final Color color;
@@ -55,6 +57,36 @@ public class HColorSimple extends HColorAbstract implements HColor {
 		return color.toString() + " alpha=" + color.getAlpha() + " monochrome=" + monochrome;
 	}
 
+	@Override
+	public String asString() {
+		if (isTransparent()) {
+			return "transparent";
+		}
+		if (color.getAlpha() == 255) {
+			return DotStringFactory.sharp000000(color.getRGB());
+		}
+		return super.asString();
+	}
+
+	@Override
+	public HColor lighten(int ratio) {
+		final float[] hsl = new HSLColor(color).getHSL();
+		hsl[2] += hsl[2] * (ratio / 100.0);
+		return new HColorSimple(new HSLColor(hsl).getRGB(), false);
+	}
+
+	@Override
+	public HColor darken(int ratio) {
+		final float[] hsl = new HSLColor(color).getHSL();
+		hsl[2] -= hsl[2] * (ratio / 100.0);
+		return new HColorSimple(new HSLColor(hsl).getRGB(), false);
+	}
+
+	@Override
+	public boolean isDark() {
+		return ColorUtils.getGrayScale(color) < 128;
+	}
+
 	public boolean isTransparent() {
 		return color.getAlpha() == 0;
 	}

src/net/sourceforge/plantuml/ugraphic/color/HSLColor.java

@@ -0,0 +1,389 @@
+package net.sourceforge.plantuml.ugraphic.color;
+
+import java.awt.Color;
+
+/**
+ * Taken from http://www.camick.com/java/source/HSLColor.java
+ * 
+ * The HSLColor class provides methods to manipulate HSL (Hue, Saturation
+ * Luminance) values to create a corresponding Color object using the RGB
+ * ColorSpace.
+ *
+ * The HUE is the color, the Saturation is the purity of the color (with respect
+ * to grey) and Luminance is the brightness of the color (with respect to black
+ * and white)
+ *
+ * The Hue is specified as an angel between 0 - 360 degrees where red is 0,
+ * green is 120 and blue is 240. In between you have the colors of the rainbow.
+ * Saturation is specified as a percentage between 0 - 100 where 100 is fully
+ * saturated and 0 approaches gray. Luminance is specified as a percentage
+ * between 0 - 100 where 0 is black and 100 is white.
+ *
+ * In particular the HSL color space makes it easier change the Tone or Shade of
+ * a color by adjusting the luminance value.
+ */
+public class HSLColor {
+	private Color rgb;
+	private float[] hsl;
+	private float alpha;
+
+	/**
+	 * Create a HSLColor object using an RGB Color object.
+	 *
+	 * @param rgb the RGB Color object
+	 */
+	public HSLColor(Color rgb) {
+		this.rgb = rgb;
+		hsl = fromRGB(rgb);
+		alpha = rgb.getAlpha() / 255.0f;
+	}
+
+	/**
+	 * Create a HSLColor object using individual HSL values and a default alpha
+	 * value of 1.0.
+	 *
+	 * @param h is the Hue value in degrees between 0 - 360
+	 * @param s is the Saturation percentage between 0 - 100
+	 * @param l is the Lumanance percentage between 0 - 100
+	 */
+	public HSLColor(float h, float s, float l) {
+		this(h, s, l, 1.0f);
+	}
+
+	/**
+	 * Create a HSLColor object using individual HSL values.
+	 *
+	 * @param h     the Hue value in degrees between 0 - 360
+	 * @param s     the Saturation percentage between 0 - 100
+	 * @param l     the Lumanance percentage between 0 - 100
+	 * @param alpha the alpha value between 0 - 1
+	 */
+	public HSLColor(float h, float s, float l, float alpha) {
+		hsl = new float[] { h, s, l };
+		this.alpha = alpha;
+		rgb = toRGB(hsl, alpha);
+	}
+
+	/**
+	 * Create a HSLColor object using an an array containing the individual HSL
+	 * values and with a default alpha value of 1.
+	 *
+	 * @param hsl array containing HSL values
+	 */
+	public HSLColor(float[] hsl) {
+		this(hsl, 1.0f);
+	}
+
+	/**
+	 * Create a HSLColor object using an an array containing the individual HSL
+	 * values.
+	 *
+	 * @param hsl   array containing HSL values
+	 * @param alpha the alpha value between 0 - 1
+	 */
+	public HSLColor(float[] hsl, float alpha) {
+		this.hsl = hsl;
+		this.alpha = alpha;
+		rgb = toRGB(hsl, alpha);
+	}
+
+	/**
+	 * Create a RGB Color object based on this HSLColor with a different Hue value.
+	 * The degrees specified is an absolute value.
+	 *
+	 * @param degrees - the Hue value between 0 - 360
+	 * @return the RGB Color object
+	 */
+	public Color adjustHue(float degrees) {
+		return toRGB(degrees, hsl[1], hsl[2], alpha);
+	}
+
+	/**
+	 * Create a RGB Color object based on this HSLColor with a different Luminance
+	 * value. The percent specified is an absolute value.
+	 *
+	 * @param percent - the Luminance value between 0 - 100
+	 * @return the RGB Color object
+	 */
+	public Color adjustLuminance(float percent) {
+		return toRGB(hsl[0], hsl[1], percent, alpha);
+	}
+
+	/**
+	 * Create a RGB Color object based on this HSLColor with a different Saturation
+	 * value. The percent specified is an absolute value.
+	 *
+	 * @param percent - the Saturation value between 0 - 100
+	 * @return the RGB Color object
+	 */
+	public Color adjustSaturation(float percent) {
+		return toRGB(hsl[0], percent, hsl[2], alpha);
+	}
+
+	/**
+	 * Create a RGB Color object based on this HSLColor with a different Shade.
+	 * Changing the shade will return a darker color. The percent specified is a
+	 * relative value.
+	 *
+	 * @param percent - the value between 0 - 100
+	 * @return the RGB Color object
+	 */
+	public Color adjustShade(float percent) {
+		float multiplier = (100.0f - percent) / 100.0f;
+		float l = Math.max(0.0f, hsl[2] * multiplier);
+
+		return toRGB(hsl[0], hsl[1], l, alpha);
+	}
+
+	/**
+	 * Create a RGB Color object based on this HSLColor with a different Tone.
+	 * Changing the tone will return a lighter color. The percent specified is a
+	 * relative value.
+	 *
+	 * @param percent - the value between 0 - 100
+	 * @return the RGB Color object
+	 */
+	public Color adjustTone(float percent) {
+		float multiplier = (100.0f + percent) / 100.0f;
+		float l = Math.min(100.0f, hsl[2] * multiplier);
+
+		return toRGB(hsl[0], hsl[1], l, alpha);
+	}
+
+	/**
+	 * Get the Alpha value.
+	 *
+	 * @return the Alpha value.
+	 */
+	public float getAlpha() {
+		return alpha;
+	}
+
+	/**
+	 * Create a RGB Color object that is the complementary color of this HSLColor.
+	 * This is a convenience method. The complementary color is determined by adding
+	 * 180 degrees to the Hue value.
+	 * 
+	 * @return the RGB Color object
+	 */
+	public Color getComplementary() {
+		float hue = (hsl[0] + 180.0f) % 360.0f;
+		return toRGB(hue, hsl[1], hsl[2]);
+	}
+
+	/**
+	 * Get the Hue value.
+	 *
+	 * @return the Hue value.
+	 */
+	public float getHue() {
+		return hsl[0];
+	}
+
+	/**
+	 * Get the HSL values.
+	 *
+	 * @return the HSL values.
+	 */
+	public float[] getHSL() {
+		return hsl;
+	}
+
+	/**
+	 * Get the Luminance value.
+	 *
+	 * @return the Luminance value.
+	 */
+	public float getLuminance() {
+		return hsl[2];
+	}
+
+	/**
+	 * Get the RGB Color object represented by this HDLColor.
+	 *
+	 * @return the RGB Color object.
+	 */
+	public Color getRGB() {
+		return rgb;
+	}
+
+	/**
+	 * Get the Saturation value.
+	 *
+	 * @return the Saturation value.
+	 */
+	public float getSaturation() {
+		return hsl[1];
+	}
+
+	public String toString() {
+		String toString = "HSLColor[h=" + hsl[0] + ",s=" + hsl[1] + ",l=" + hsl[2] + ",alpha=" + alpha + "]";
+
+		return toString;
+	}
+
+	/**
+	 * Convert a RGB Color to it corresponding HSL values.
+	 *
+	 * @return an array containing the 3 HSL values.
+	 */
+	public static float[] fromRGB(Color color) {
+		// Get RGB values in the range 0 - 1
+
+		float[] rgb = color.getRGBColorComponents(null);
+		float r = rgb[0];
+		float g = rgb[1];
+		float b = rgb[2];
+
+		// Minimum and Maximum RGB values are used in the HSL calculations
+
+		float min = Math.min(r, Math.min(g, b));
+		float max = Math.max(r, Math.max(g, b));
+
+		// Calculate the Hue
+
+		float h = 0;
+
+		if (max == min)
+			h = 0;
+		else if (max == r)
+			h = ((60 * (g - b) / (max - min)) + 360) % 360;
+		else if (max == g)
+			h = (60 * (b - r) / (max - min)) + 120;
+		else if (max == b)
+			h = (60 * (r - g) / (max - min)) + 240;
+
+		// Calculate the Luminance
+
+		float l = (max + min) / 2;
+
+		// Calculate the Saturation
+
+		float s = 0;
+
+		if (max == min)
+			s = 0;
+		else if (l <= .5f)
+			s = (max - min) / (max + min);
+		else
+			s = (max - min) / (2 - max - min);
+
+		return new float[] { h, s * 100, l * 100 };
+	}
+
+	/**
+	 * Convert HSL values to a RGB Color with a default alpha value of 1. H (Hue) is
+	 * specified as degrees in the range 0 - 360. S (Saturation) is specified as a
+	 * percentage in the range 1 - 100. L (Lumanance) is specified as a percentage
+	 * in the range 1 - 100.
+	 *
+	 * @param hsl an array containing the 3 HSL values
+	 *
+	 * @returns the RGB Color object
+	 */
+	public static Color toRGB(float[] hsl) {
+		return toRGB(hsl, 1.0f);
+	}
+
+	/**
+	 * Convert HSL values to a RGB Color. H (Hue) is specified as degrees in the
+	 * range 0 - 360. S (Saturation) is specified as a percentage in the range 1 -
+	 * 100. L (Lumanance) is specified as a percentage in the range 1 - 100.
+	 *
+	 * @param hsl   an array containing the 3 HSL values
+	 * @param alpha the alpha value between 0 - 1
+	 *
+	 * @returns the RGB Color object
+	 */
+	public static Color toRGB(float[] hsl, float alpha) {
+		return toRGB(hsl[0], hsl[1], hsl[2], alpha);
+	}
+
+	/**
+	 * Convert HSL values to a RGB Color with a default alpha value of 1.
+	 *
+	 * @param h Hue is specified as degrees in the range 0 - 360.
+	 * @param s Saturation is specified as a percentage in the range 1 - 100.
+	 * @param l Lumanance is specified as a percentage in the range 1 - 100.
+	 *
+	 * @returns the RGB Color object
+	 */
+	public static Color toRGB(float h, float s, float l) {
+		return toRGB(h, s, l, 1.0f);
+	}
+
+	/**
+	 * Convert HSL values to a RGB Color.
+	 *
+	 * @param h     Hue is specified as degrees in the range 0 - 360.
+	 * @param s     Saturation is specified as a percentage in the range 1 - 100.
+	 * @param l     Lumanance is specified as a percentage in the range 1 - 100.
+	 * @param alpha the alpha value between 0 - 1
+	 *
+	 * @returns the RGB Color object
+	 */
+	public static Color toRGB(float h, float s, float l, float alpha) {
+		if (s < 0.0f || s > 100.0f) {
+			String message = "Color parameter outside of expected range - Saturation";
+			throw new IllegalArgumentException(message);
+		}
+
+		if (l < 0.0f || l > 100.0f) {
+			String message = "Color parameter outside of expected range - Luminance";
+			throw new IllegalArgumentException(message);
+		}
+
+		if (alpha < 0.0f || alpha > 1.0f) {
+			String message = "Color parameter outside of expected range - Alpha";
+			throw new IllegalArgumentException(message);
+		}
+
+		// Formula needs all values between 0 - 1.
+
+		h = h % 360.0f;
+		h /= 360f;
+		s /= 100f;
+		l /= 100f;
+
+		float q = 0;
+
+		if (l < 0.5)
+			q = l * (1 + s);
+		else
+			q = (l + s) - (s * l);
+
+		float p = 2 * l - q;
+
+		float r = Math.max(0, HueToRGB(p, q, h + (1.0f / 3.0f)));
+		float g = Math.max(0, HueToRGB(p, q, h));
+		float b = Math.max(0, HueToRGB(p, q, h - (1.0f / 3.0f)));
+
+		r = Math.min(r, 1.0f);
+		g = Math.min(g, 1.0f);
+		b = Math.min(b, 1.0f);
+
+		return new Color(r, g, b, alpha);
+	}
+
+	private static float HueToRGB(float p, float q, float h) {
+		if (h < 0)
+			h += 1;
+
+		if (h > 1)
+			h -= 1;
+
+		if (6 * h < 1) {
+			return p + ((q - p) * 6 * h);
+		}
+
+		if (2 * h < 1) {
+			return q;
+		}
+
+		if (3 * h < 2) {
+			return p + ((q - p) * 6 * ((2.0f / 3.0f) - h));
+		}
+
+		return p;
+	}
+}

src/net/sourceforge/plantuml/version/Version.java

@@ -80,7 +80,7 @@ public class Version {
 	}
 
 	public static int beta() {
-		final int beta = 2;
+		final int beta = 4;
 		return beta;
 	}