1 /**
   2  * @test
   3  * @bug 6216010
   4  * @summary check to see that underline thickness scales.
   5  * @run main UnderlineTest
   6  */
   7 
   8 import java.awt.Color;
   9 import java.awt.Container;
  10 import java.awt.Dimension;
  11 import java.awt.Font;
  12 import java.awt.Graphics;
  13 import java.awt.Graphics2D;
  14 import java.awt.GridLayout;
  15 import java.awt.font.FontRenderContext;
  16 import java.awt.font.LineMetrics;
  17 import java.awt.font.TextAttribute;
  18 import java.awt.font.TextLayout;
  19 import java.awt.geom.AffineTransform;
  20 import java.util.HashMap;
  21 import javax.swing.JComponent;
  22 import javax.swing.JFrame;
  23 import javax.swing.JScrollPane;
  24 
  25 public class UnderlineTest {
  26     static class FontsPanel extends Container {
  27         FontsPanel(Font[] fonts) {
  28             setLayout(new GridLayout(0, 1));
  29             for (int i = 0; i < fonts.length; ++i) {
  30               add(new FontPanel(fonts[i]));
  31             }
  32         }
  33     }
  34 
  35     static String fps = "Stellar glyphs";
  36     static Dimension fpd = new Dimension(600, 120);
  37     static class FontPanel extends JComponent {
  38         Font f;
  39         FontPanel(Font f) {
  40             this.f = f;
  41             setPreferredSize(fpd);
  42             setMinimumSize(fpd);
  43             setMaximumSize(fpd);
  44             setSize(fpd);
  45         }
  46 
  47         public void paintComponent(Graphics g) {
  48             g.setColor(Color.WHITE);
  49             g.fillRect(0, 0, fpd.width, fpd.height);
  50 
  51             g.setColor(Color.RED);
  52             FontRenderContext frc = ((Graphics2D)g).getFontRenderContext();
  53             LineMetrics lm = f.getLineMetrics(fps, frc);
  54             int h = (int)(fpd.height - 20 - lm.getAscent());
  55             g.drawLine(20, h, fpd.width - 20, h);
  56             h = fpd.height - 20;
  57             g.drawLine(20, h, fpd.width - 20, h);
  58             h = (int)(fpd.height - 20 + lm.getDescent());
  59             g.drawLine(20, h, fpd.width - 20, h);
  60 
  61             g.setColor(Color.BLACK);
  62             g.setFont(f);
  63             g.drawString(fps, 50, fpd.height - 20);
  64         }
  65     }
  66 
  67     public static void main(String args[]) {
  68         String fontName = "Lucida Sans";
  69         if (args.length > 0) {
  70             fontName = args[0];
  71         }
  72         FontRenderContext frc = new FontRenderContext(null, false, false);
  73         FontRenderContext frc2 = new FontRenderContext(AffineTransform.getScaleInstance(1.5, 1.5), false, false);
  74 
  75         Font font0 = new Font(fontName, 0, 20);
  76         HashMap map = new HashMap();
  77         map.put(TextAttribute.UNDERLINE, TextAttribute.UNDERLINE_ON);
  78         map.put(TextAttribute.STRIKETHROUGH, TextAttribute.STRIKETHROUGH_ON);
  79         Font font = font0.deriveFont(map);
  80 
  81         System.out.println("Using font: " + font);
  82 
  83         double rot = -Math.PI/4;
  84         AffineTransform scrtx = AffineTransform.getRotateInstance(rot);
  85         scrtx.scale(1, 2);
  86 
  87         Font[] fonts = {
  88             font.deriveFont(1f),
  89             font.deriveFont(20f),
  90             font.deriveFont(40f),
  91             font.deriveFont(80f),
  92             font.deriveFont(AffineTransform.getRotateInstance(rot)),
  93             font.deriveFont(AffineTransform.getScaleInstance(1, 2)),
  94             font.deriveFont(AffineTransform.getScaleInstance(2, 4)),
  95             font.deriveFont(scrtx),
  96         };
  97 
  98         LineMetrics[] metrics = new LineMetrics[fonts.length * 2];
  99         for (int i = 0; i < metrics.length; ++i) {
 100             Font f = fonts[i % fonts.length];
 101             FontRenderContext frcx = i < fonts.length ? frc : frc2;
 102             metrics[i] = f.getLineMetrics("X", frcx);
 103       //       dumpMetrics("Metrics for " + f.getSize2D() + " pt. font,\n  tx: " +
 104       //       f.getTransform() + ",\n   frctx: " + frcx.getTransform(), metrics[i]);
 105         }
 106 
 107         // test for linear scale
 108         // this seems to work, might need to get fancy to deal with last-significant-bit issues?
 109         double ds1 = metrics[2].getStrikethroughOffset() - metrics[1].getStrikethroughOffset();
 110         double du1 = metrics[2].getUnderlineThickness() - metrics[1].getUnderlineThickness();
 111         double ds2 = metrics[3].getStrikethroughOffset() - metrics[2].getStrikethroughOffset();
 112         double du2 = metrics[3].getUnderlineThickness() - metrics[2].getUnderlineThickness();
 113         if (ds2 != ds1 * 2 || du2 != du1 * 2) {
 114             throw new IllegalStateException("non-linear scale: " + ds1 + " / " + ds2 + ", " +
 115                                             du1 + " / " + du2);
 116         }
 117 
 118         JFrame jf = new JFrame("Fonts");
 119         jf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
 120         jf.add(new JScrollPane(new FontsPanel(fonts)));
 121         jf.pack();
 122         jf.setVisible(true);
 123     }
 124 
 125     static void dumpMetrics(String header, LineMetrics lm) {
 126         if (header != null) {
 127             System.out.println(header);
 128         }
 129         System.out.println("asc: " + lm.getAscent());
 130         System.out.println("dsc: " + lm.getDescent());
 131         System.out.println("ulo: " + lm.getUnderlineOffset());
 132         System.out.println("ult: " + lm.getUnderlineThickness());
 133         System.out.println("sto: " + lm.getStrikethroughOffset());
 134         System.out.println("stt: " + lm.getStrikethroughThickness());
 135     }
 136 }