Add Support for Font Selection in Ditaa

This adds support for selecting the font in ditaa diagrams by specifying
--font-family, --font-size and/or --font-variant in the ditaa() line.

The change is actually taken over from @pepijnve who implemented in
https://github.com/pepijnve/ditaa/issues/1. I extended it for supporting
the necessary flags from plantuml.

src/net/sourceforge/plantuml/ditaa/PSystemDitaa.java

@@ -34,6 +34,7 @@
  */
 package net.sourceforge.plantuml.ditaa;
 
+import java.awt.Font;
 import java.awt.image.BufferedImage;
 import java.io.IOException;
 import java.io.OutputStream;
@@ -61,11 +62,12 @@ public class PSystemDitaa extends AbstractPSystem {
 	private final boolean dropShadows;
 	private final String data;
 	private final float scale;
+	private final Font font;
 	private final boolean performSeparationOfCommonEdges;
 	private final boolean allCornersAreRound;
 
 	public PSystemDitaa(UmlSource source, String data, boolean performSeparationOfCommonEdges, boolean dropShadows,
-			boolean allCornersAreRound, float scale) {
+			boolean allCornersAreRound, float scale, Font font) {
 		super(source);
 		this.data = data;
 		this.dropShadows = dropShadows;
@@ -84,11 +86,12 @@ public class PSystemDitaa extends AbstractPSystem {
 			this.processingOptions = null;
 		}
 		this.scale = scale;
+		this.font = font;
 	}
 
 	PSystemDitaa add(String line) {
 		return new PSystemDitaa(getSource(), data + line + BackSlash.NEWLINE, performSeparationOfCommonEdges,
-				dropShadows, allCornersAreRound, scale);
+				dropShadows, allCornersAreRound, scale, font);
 	}
 
 	public DiagramDescription getDescription() {
@@ -113,6 +116,10 @@ public class PSystemDitaa extends AbstractPSystem {
 			final Field f_renderingOptions = options.getClass().getField("renderingOptions");
 			final Object renderingOptions = f_renderingOptions.get(options);
 
+			// renderingOptions.setFont(font);
+			final Method setFont = renderingOptions.getClass().getMethod("setFont", Font.class);
+			setFont.invoke(renderingOptions, font);
+
 			// renderingOptions.setScale(scale);
 			final Method setScale = renderingOptions.getClass().getMethod("setScale", float.class);
 			setScale.invoke(renderingOptions, scale);

src/net/sourceforge/plantuml/ditaa/PSystemDitaaFactory.java

@@ -34,6 +34,7 @@
  */
 package net.sourceforge.plantuml.ditaa;
 
+import java.awt.Font;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
@@ -70,10 +71,11 @@ public class PSystemDitaaFactory extends PSystemBasicFactory<PSystemDitaa> {
 			allCornersAreRound = true;
 
 		final float scale = extractScale(startLine);
+		final Font font = extractFont(startLine);
 		if (getDiagramType() == DiagramType.UML)
 			return null;
 		else if (getDiagramType() == DiagramType.DITAA)
-			return new PSystemDitaa(source, "", performSeparationOfCommonEdges, dropShadows, allCornersAreRound, scale);
+			return new PSystemDitaa(source, "", performSeparationOfCommonEdges, dropShadows, allCornersAreRound, scale, font);
 		else
 			throw new IllegalStateException(getDiagramType().name());
 
@@ -95,7 +97,8 @@ public class PSystemDitaaFactory extends PSystemBasicFactory<PSystemDitaa> {
 				allCornersAreRound = true;
 
 			final float scale = extractScale(line);
-			return new PSystemDitaa(source, "", performSeparationOfCommonEdges, dropShadows, allCornersAreRound, scale);
+			final Font font = extractFont(line);
+			return new PSystemDitaa(source, "", performSeparationOfCommonEdges, dropShadows, allCornersAreRound, scale, font);
 		}
 		if (system == null)
 			return null;
@@ -115,4 +118,46 @@ public class PSystemDitaaFactory extends PSystemBasicFactory<PSystemDitaa> {
 		}
 		return 1;
 	}
+
+	private Font extractFont(String line) {
+		if (line == null)
+			return new Font("Dialog", Font.BOLD, 12);
+
+		final Pattern pName = Pattern.compile("font-family=([a-zA-Z0-0 ]+)");
+		final Matcher mName = pName.matcher(line);
+		String fontName = "Dialog";
+		if (mName.find())
+		{
+			fontName = mName.group(1);
+		}
+
+		final Pattern pVariant = Pattern.compile("font-variant=(BOLD|ITALIC|PLAIN)");
+		final Matcher mVariant = pVariant.matcher(line);
+		int fontVariant = Font.BOLD;
+		if (mVariant.find())
+		{
+			switch (mVariant.group(1))
+			{
+				case "BOLD":
+					fontVariant = Font.BOLD;
+					break;
+				case "ITALIC":
+					fontVariant = Font.ITALIC;
+					break;
+				case "PLAIN":
+					fontVariant = Font.PLAIN;
+					break;
+			}
+		}
+
+		final Pattern pSize = Pattern.compile("font-size=([\\d]+)");
+		final Matcher mSize = pSize.matcher(line);
+		int fontSize = 12;
+		if (mSize.find())
+		{
+			fontSize = Integer.parseInt(mSize.group(1));
+		}
+
+		return new Font(fontName, fontVariant, fontSize);
+	}
 }

src/org/stathissideris/ascii2image/core/RenderingOptions.java

@@ -20,6 +20,7 @@
  */
 package org.stathissideris.ascii2image.core;
 
+import java.awt.*;
 import java.util.HashMap;
 
 import org.stathissideris.ascii2image.graphics.CustomShapeDefinition;
@@ -41,6 +42,8 @@ public class RenderingOptions {
 	
 	private float scale = 1;
 
+	private Font font = new Font("Dialog", Font.BOLD, 12);
+
 	/**
 	 * @return
 	 */
@@ -113,4 +116,14 @@ public class RenderingOptions {
 		antialias = b;
 	}
 
+	public Font getFont()
+	{
+		return font;
+	}
+
+	public void setFont(Font font)
+	{
+		this.font = font;
+	}
+
 }

src/org/stathissideris/ascii2image/graphics/Diagram.java

@@ -111,6 +111,8 @@ public class Diagram {
 		this.cellWidth = options.renderingOptions.getCellWidth();
 		this.cellHeight = options.renderingOptions.getCellHeight();
 
+		FontMeasurer fontMeasurer = new FontMeasurer(options.renderingOptions.getFont());
+
 		width = grid.getWidth() * cellWidth;
 		height = grid.getHeight() * cellHeight;
 
@@ -526,7 +528,7 @@ public class Diagram {
 		ArrayList textGroups = nonBlank.breakIntoDistinctBoundaries();
 		if(DEBUG) System.out.println(textGroups.size()+" text groups found");
 
-		Font font = FontMeasurer.instance().getFontFor(cellHeight);
+		Font font = fontMeasurer.getFontFor(cellHeight);
 
 		Iterator textGroupIt = textGroups.iterator();
 		while(textGroupIt.hasNext()){
@@ -550,10 +552,10 @@ public class Diagram {
 				int maxX = getCellMaxX(lastCell);
 
 				DiagramText textObject;
-				if(FontMeasurer.instance().getWidthFor(string, font) > maxX - minX){ //does not fit horizontally
-					Font lessWideFont = FontMeasurer.instance().getFontFor(maxX - minX, string);
-					textObject = new DiagramText(minX, y, string, lessWideFont);
-				} else textObject = new DiagramText(minX, y, string, font);
+				if(fontMeasurer.getWidthFor(string, font) > maxX - minX){ //does not fit horizontally
+					Font lessWideFont = fontMeasurer.getFontFor(maxX - minX, string);
+					textObject = new DiagramText(minX, y, string, lessWideFont, fontMeasurer);
+				} else textObject = new DiagramText(minX, y, string, font, fontMeasurer);
 
 				textObject.centerVerticallyBetween(getCellMinY(cell), getCellMaxY(cell));
 

src/org/stathissideris/ascii2image/graphics/DiagramText.java

@@ -39,8 +39,9 @@ public class DiagramText extends DiagramComponent {
 	private boolean isTextOnLine = false;
 	private boolean hasOutline = false;
 	private Color outlineColor = Color.white;
+	private final FontMeasurer fontMeasurer;
 
-	public DiagramText(int x, int y, String text, Font font){
+	public DiagramText(int x, int y, String text, Font font, FontMeasurer fontMeasurer){
 		if(text == null) throw new IllegalArgumentException("DiagramText cannot be initialised with a null string");
 		if(font == null) throw new IllegalArgumentException("DiagramText cannot be initialised with a null font");
 
@@ -48,6 +49,7 @@ public class DiagramText extends DiagramComponent {
 		this.yPos = y;
 		this.text = text;
 		this.font = font;
+		this.fontMeasurer = fontMeasurer;
 	}
 
 	public void centerInBounds(Rectangle2D bounds){
@@ -56,20 +58,20 @@ public class DiagramText extends DiagramComponent {
 	}
 
 	public void centerHorizontallyBetween(int minX, int maxX){
-		int width = FontMeasurer.instance().getWidthFor(text, font);
+		int width = fontMeasurer.getWidthFor(text, font);
 		int center = Math.abs(maxX - minX) / 2;
 		xPos += Math.abs(center - width / 2);
 		
 	}
 
 	public void centerVerticallyBetween(int minY, int maxY){
-		int zHeight = FontMeasurer.instance().getZHeight(font);
+		int zHeight = fontMeasurer.getZHeight(font);
 		int center = Math.abs(maxY - minY) / 2;
 		yPos -= Math.abs(center - zHeight / 2);
 	}
 
 	public void alignRightEdgeTo(int x){
-		int width = FontMeasurer.instance().getWidthFor(text, font);
+		int width = fontMeasurer.getWidthFor(text, font);
 		xPos = x - width;
 	}
 
@@ -145,7 +147,7 @@ public class DiagramText extends DiagramComponent {
 	}
 
 	public Rectangle2D getBounds(){
-		Rectangle2D bounds = FontMeasurer.instance().getBoundsFor(text, font);
+		Rectangle2D bounds = fontMeasurer.getBoundsFor(text, font);
 		bounds.setRect(
 			bounds.getMinX() + xPos,
 			bounds.getMinY() + yPos,

src/org/stathissideris/ascii2image/graphics/FontMeasurer.java

@@ -26,32 +26,25 @@ import java.awt.Graphics2D;
 import java.awt.font.FontRenderContext;
 import java.awt.geom.Rectangle2D;
 import java.awt.image.BufferedImage;
-import java.util.Locale;
 
 /**
  * 
  * @author Efstathios Sideris
  */
 public class FontMeasurer {
-	
-	private static final String fontFamilyName = "Dialog";
-	//private static final String fontFamilyName = "Helvetica";
-	
-	private static final boolean DEBUG = false;
-	
-	private static final FontMeasurer instance = new FontMeasurer();
-	FontRenderContext fakeRenderContext;
-	Graphics2D fakeGraphics;
-	
-	{   
+
+	private final Font baseFont;
+	private FontRenderContext fakeRenderContext;
+	private Graphics2D fakeGraphics;
+
+	public FontMeasurer(Font font){
+		baseFont = font;
+
 		BufferedImage image = new BufferedImage(1,1, BufferedImage.TYPE_INT_RGB);
 		fakeGraphics = image.createGraphics();
 		
-		if (DEBUG) System.out.println("Locale: "+Locale.getDefault());
-		
 		fakeRenderContext = fakeGraphics.getFontRenderContext();
-	}		 
-	
+	}
 
 	public int getWidthFor(String str, int pixelHeight){
 		Font font = getFontFor(pixelHeight);
@@ -74,125 +67,86 @@ public class FontMeasurer {
 		Rectangle2D rectangle = font.getStringBounds(str, fakeRenderContext);
 		return (int) rectangle.getHeight();
 	}
-	
+
 	public Rectangle2D getBoundsFor(String str, Font font){
 		return font.getStringBounds(str, fakeRenderContext);
 	}
-	
-	public Font getFontFor(int pixelHeight){
-		BufferedImage image = new BufferedImage(1,1, BufferedImage.TYPE_INT_RGB);
-		Graphics2D g2 = image.createGraphics();
-		return getFontFor(pixelHeight, fakeRenderContext);
-	}
 
 	public int getAscent(Font font){
 		fakeGraphics.setFont(font);
 		FontMetrics metrics = fakeGraphics.getFontMetrics();
-		if(DEBUG) System.out.println("Ascent: "+metrics.getAscent());
 		return metrics.getAscent();
 	}
 
 	public int getZHeight(Font font){
-		int height = (int) font.createGlyphVector(fakeRenderContext, "Z").getOutline().getBounds().getHeight();
-		if(DEBUG) System.out.println("Z height: "+height);
-		return height;
+		return (int) font.createGlyphVector(fakeRenderContext, "Z").getOutline().getBounds().getHeight();
 	}
 
-	public Font getFontFor(int maxWidth, String string){
-		float size = 12;
-		Font currentFont = new Font(fontFamilyName, Font.BOLD, (int) size);
-		//ascent is the distance between the baseline and the tallest character
-		int width = getWidthFor(string, currentFont);
+	public Font getFontFor(final int maxWidth, final String string){
+		FontPredicate predicate = new FontPredicate() {
+			@Override
+			public boolean test(Font font)
+			{
+				int width = getWidthFor(string, font);
+				return width > maxWidth;
+			}
+		};
+
+		return deriveFont(predicate, 1.0f);
+	}
+
+	public Font getFontFor(final int pixelHeight){
+		FontPredicate predicate = new FontPredicate() {
+			@Override
+			public boolean test(Font font)
+			{
+				//ascent is the distance between the baseline and the tallest character
+				int ascent = getAscent(font);
+				return ascent > pixelHeight;
+			}
+		};
+
+		return deriveFont(predicate, 0.5f);
+	}
+
+	private Font deriveFont(FontPredicate predicate, float sizeDelta)
+	{
+		Font currentFont = baseFont;
+		float size = baseFont.getSize2D();
 
 		int direction; //direction of size change (towards smaller or bigger)
-		if(width > maxWidth){
-			currentFont = currentFont.deriveFont(size - 1);
+		if(predicate.test(currentFont)){
+			currentFont = currentFont.deriveFont(size - 1f);
 			size--;
-			direction = -1; 
+			direction = -1;
 		} else {
-			currentFont = currentFont.deriveFont(size + 1);
+			currentFont = currentFont.deriveFont(size + 1f);
 			size++;
 			direction = 1;
 		}
+
 		while(size > 0){
 			currentFont = currentFont.deriveFont(size);
 			//rectangle = currentFont.getStringBounds(testString, frc);
-			width = getWidthFor(string, currentFont);
-			if(direction == 1){
-				if(width > maxWidth){
-					size = size - 1;
+			if (direction == 1) {
+				if (predicate.test(currentFont)) {
+					size = size - sizeDelta;
 					return currentFont.deriveFont(size);
+				} else {
+					size = size + sizeDelta;
 				}
-				else size = size + 1;
 			} else {
-				if(width < maxWidth)
+				if (!predicate.test(currentFont)) {
 					return currentFont;
-				else size = size - 1;
+				} else {
+					size = size - sizeDelta;
+				}
 			}
 		}
 		return null;
 	}
 
-
-
-	public Font getFontFor(int pixelHeight, FontRenderContext frc){
-		float size = 12;
-		Font currentFont = new Font(fontFamilyName, Font.BOLD, (int) size);
-//		Font currentFont = new Font("Times", Font.BOLD, (int) size);
-		if (DEBUG) System.out.println(currentFont.getFontName());
-		//ascent is the distance between the baseline and the tallest character
-		int ascent = getAscent(currentFont);
-
-		int direction; //direction of size change (towards smaller or bigger)
-		if(ascent > pixelHeight){
-			currentFont = currentFont.deriveFont(size - 1);
-			size--;
-			direction = -1; 
-		} else {
-			currentFont = currentFont.deriveFont(size + 1);
-			size++;
-			direction = 1;
-		}
-		while(size > 0){
-			currentFont = currentFont.deriveFont(size);
-			//rectangle = currentFont.getStringBounds(testString, frc);
-			ascent = getAscent(currentFont);
-			if(direction == 1){
-				if(ascent > pixelHeight){
-					size = size - 0.5f;
-					return currentFont.deriveFont(size);
-				}
-				else size = size + 0.5f;
-			} else {
-				if(ascent < pixelHeight)
-					return currentFont;
-				else size = size - 0.5f;
-			}
-		}
-		return null;
-	}
-	
-	public static FontMeasurer instance(){
-		return instance;
-	}
-	
-	public FontMeasurer(){
-	}
-	
-	public static void main(String[] args) {
-		//FontMeasurer.instance().getFontFor(7);
-		float size = 12;
-		Font currentFont = new Font("Sans", Font.BOLD, (int) size);
-		System.out.println(currentFont.getSize());
-		currentFont = currentFont.deriveFont(--size);
-		System.out.println(currentFont.getSize());
-		currentFont = currentFont.deriveFont(--size);
-		System.out.println(currentFont.getSize());
-		currentFont = currentFont.deriveFont(--size);
-		System.out.println(currentFont.getSize());
-		currentFont = currentFont.deriveFont(--size);
-		System.out.println(currentFont.getSize());
-		currentFont = currentFont.deriveFont(--size);
-		System.out.println(currentFont.getSize());
+	private interface FontPredicate {
+		boolean test(Font font);
 	}
 }