Question

I’m trying to use setStroke and BasicStroke to draw random thickness lines.

here is the painting code

 public void paintComponent(Graphics g1) {
        Random rand = new Random();
        Graphics g2 = (Graphics2D) g1;

        //set background color
        g2.setColor(Color.white);
        g2.fillRect(0, 0, getWidth(), getHeight());
        Dimension d = getPreferredSize();

        //set  line's color

        float r = rand.nextFloat();
        float g = rand.nextFloat();
        float b = rand.nextFloat();

        Color randomColor = new Color(r,g,b);

        g2.setColor(randomColor);

        //set line's stroke

        float width = rand.nextFloat();

        BasicStroke randomStroke = new BasicStroke(width);


        ((Graphics2D) g2).setStroke(randomStroke);


        for (Line2D.Double line : lines) {
            g2.drawLine(
                (int)line.getX1(),
                (int)line.getY1(),
                (int)line.getX2(),
                (int)line.getY2()
                );
        }
    }

when I set the width of stroke to a certain number, it can draw correctly. I looked up the BasicStroke class, it have the following parameters:

  float width;
  int join;
  int cap;
  float miterlimit;
  float[] dash;
  float dash_phase;

Besides width, I’m not sure what are the others function.
How can I use the BasicStroke to generate random thickness lines?

Answer 1

I think the biggest problem is that nextFloat() is returning values between 0 and 1 – where I’m guessing you want numbers greater than 1 in order to be able to see any visible difference in line thickness.

Besides width, I’m not sure what are the others function.

Please refer to the Javadocs .