Stili črt

5.1 Lastnosti črt

• BasicStroke()

Kreira BasicStroke z debelino pisala 1.0 in nastavitvijo zaključka črte CAP_SQUARE ter vmesne povezave JOIN_MITER. Lahko pa podamo svoje začetne nastavitve:
• BasicStroke(float penWidth)

Določi širino pisala.
• BasicStroke(float penWidth, int capStyle, int joinStyle)

Določi vse tri lastnosti. capStyle (zaključek črte) je lahko: CAP_SQUARE, CAP_BUTT ali CAP_ROUND (glej točko 5.5).
joinStyle (vmesni člen) je lahko: JOIN_MITER, JOIN_BEVEL ali JOIN_ROUND (round off corner with circle with diameter equal to the pen width).
• BasicStroke(float penWidth, int capStyle, int joinStyle, float miterLimit)

Kot zgoraj, le da lahko določimo še kako daleč gre "mitter" členek. Skušajte se izogniti temule.
• BasicStroke(float penWidth, int capStyle, int joinStyle, float miterLimit, float[] dashPattern, float dashOffset)

S tem lahko ustvarimo prekinjene črte iz polnih (sodo zaporedje) in prosojnih elementov (liho zaporedje). Odmik (dashOffset) je običajno 0.0 in določa kje se začne zaporedje elementov.

5.2 Debelina črt: Primer programa

import java.awt.*;

public class DrawExample4 extends DrawExample3 {

  public void paintComponent(Graphics g) {

    Graphics2D g2d = (Graphics2D)g;

    g2d.clearRect(0, 0, getSize().width, getSize().height);

    drawFilledCircle(g2d);

    drawBigString(g2d);

    drawHollowCircle(g2d);

  }



  protected void drawHollowCircle(Graphics2D g2d) {

    g2d.setPaint(Color.blue);

    g2d.setStroke(new BasicStroke(8.0F));

    g2d.draw(getCircle());

  }



  public static void main(String[] args) {

    WindowUtil.openInJFrame(new DrawExample4(), 380, 400);

  }

}

5.3 Debelina črt

5.4 Stili zaključkov in medsebojnih povezav črt: Primer programa

import com.sun.java.swing.*;

import java.awt.*;

import java.awt.geom.*;



/** An example of line cap and join styles with
 *  Java2D in Java 1.2.
 *  1998 Marty Hall, http://www.apl.jhu.edu/~hall/java/
 */



public class LineStyles extends JPanel {

  private GeneralPath path;

  private static float x = 30, deltaX = 150, y = 300, deltaY = 250,thickness = 40;

  private Circle p1Large, p1Small, p2Large, p2Small,p3Large, p3Small;

  private int compositeType = AlphaComposite.SRC_OVER;

  private AlphaComposite transparentComposite =

    AlphaComposite.getInstance(compositeType, 0.4f);



  public LineStyles() {

    path = new GeneralPath();

    path.moveTo(x, y);

    p1Large = new Circle(x, y, thickness/2);

    p1Small = new Circle(x, y, 2);

    path.lineTo(x + deltaX, y - deltaY);

    p2Large = new Circle(x + deltaX, y - deltaY, thickness/2);

    p2Small = new Circle(x + deltaX, y - deltaY, 2);

    path.lineTo(x + 2*deltaX, y);

    p3Large = new Circle(x + 2*deltaX, y, thickness/2);

    p3Small = new Circle(x + 2*deltaX, y, 2);

    setForeground(Color.blue);

    setFont(new Font("SansSerif", Font.BOLD, 20));

  }



  public void paintComponent(Graphics g) {

    Graphics2D g2d = (Graphics2D)g;

    g2d.clearRect(0, 0, getSize().width, getSize().height);

    g2d.setColor(Color.blue);

    // Default cap and join style

    BasicStroke stroke =
      new BasicStroke(thickness,
                      BasicStroke.CAP_SQUARE,
                      BasicStroke.JOIN_MITER);

    g2d.setStroke(stroke);

    g2d.draw(path);

    drawPoints(g2d, "CAP_SQUARE", "JOIN_MITER");

    g2d.translate(3*x + 2*deltaX, 0);

    stroke = new BasicStroke(thickness,
                             BasicStroke.CAP_BUTT,
                             BasicStroke.JOIN_BEVEL);

    g2d.setStroke(stroke);

    g2d.draw(path);

    drawPoints(g2d, "CAP_BUTT", "JOIN_BEVEL");

    g2d.translate(3*x + 2*deltaX, 0);

    stroke = new BasicStroke(thickness,
                             BasicStroke.CAP_ROUND,
                             BasicStroke.JOIN_ROUND);

    g2d.setStroke(stroke);

    g2d.draw(path);

    drawPoints(g2d, "CAP_ROUND", "JOIN_ROUND");

  }



  private void drawPoints(Graphics2D g2d,String capLabel,

                          String joinLabel) {

    Paint origPaint = g2d.getPaint();

    Composite origComposite = g2d.getComposite();

    g2d.setPaint(Color.red);

    g2d.setComposite(transparentComposite);

    g2d.fill(p1Large);

    g2d.fill(p2Large);

    g2d.fill(p3Large);

    g2d.setPaint(Color.yellow);

    g2d.setComposite(origComposite);

    g2d.fill(p1Small);

    g2d.fill(p2Small);

    g2d.fill(p3Small);

    g2d.setPaint(Color.black);

    g2d.drawString(capLabel, x + thickness -5, y + 5);

    g2d.drawString(joinLabel, x + deltaX + thickness - 5, y - deltaY);

    g2d.setPaint(origPaint);

  }



  public static void main(String[] args) {

    WindowUtil.openInJFrame(new LineStyles(),

                            (int)(9*x + 6*deltaX),

                            (int)(y + 60));

  }

}



class Circle extends Ellipse2D.Double {

  public Circle(double centerX, double centerY,

                double radius) {

    super(centerX - radius, centerY - radius,

          2.0*radius, 2.0*radius);

  }

}

5.5 Stili zaključkov in medsebojnih povezav črt: Izgled izpisa

avtor: Filip Božič
december, 1998