po polsku
SineWave.java
//: c14:SineWave.java
// Drawing with Swing, using a JSlider.
// <applet code=SineWave width=700 height=400></applet>
import javax.swing.*;
import javax.swing.event.*;
import java.awt.*;
import com.bruceeckel.swing.*;
class SineDraw extends JPanel {
private static final int SCALEFACTOR = 200;
private int cycles;
private int points;
private double[] sines;
private int[] pts;
public SineDraw() { setCycles(5); }
public void setCycles(int newCycles) {
cycles = newCycles;
points = SCALEFACTOR * cycles * 2;
sines = new double[points];
for(int i = 0; i < points; i++) {
double radians = (Math.PI/SCALEFACTOR) * i;
sines[i] = Math.sin(radians);
}
repaint();
}
public void paintComponent(Graphics g) {
super.paintComponent(g);
int maxWidth = getWidth();
double hstep = (double)maxWidth/(double)points;
int maxHeight = getHeight();
pts = new int[points];
for(int i = 0; i < points; i++)
pts[i] =
(int)(sines[i] * maxHeight/2 * .95 + maxHeight/2);
g.setColor(Color.RED);
for(int i = 1; i < points; i++) {
int x1 = (int)((i - 1) * hstep);
int x2 = (int)(i * hstep);
int y1 = pts[i-1];
int y2 = pts[i];
g.drawLine(x1, y1, x2, y2);
}
}
}
public class SineWave extends JApplet {
private SineDraw sines = new SineDraw();
private JSlider adjustCycles = new JSlider(1, 30, 5);
public void init() {
Container cp = getContentPane();
cp.add(sines);
adjustCycles.addChangeListener(new ChangeListener() {
public void stateChanged(ChangeEvent e) {
sines.setCycles(
((JSlider)e.getSource()).getValue());
}
});
cp.add(BorderLayout.SOUTH, adjustCycles);
}
public static void main(String[] args) {
Console.run(new SineWave(), 700, 400);
}
} ///:~
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