/*
*----------------------------------
* 2110101 Computer Programming
* Lab #1 : Edit+Compile+Launch
* Author : somchaip@chula.ac.th
* Date : 21/06/2545
*----------------------------------
*/
import jlab.*;
import java.awt.*;
import java.awt.event.*;
import java.applet.*;
public class Mandelbrot extends Applet implements MouseListener, MouseMotionListener {
private int curWidth, curHeight;
private Image imageBuffer = null;
private Graphics gBuffer;
private Cursor cursorWait, cursorCross;
private boolean isDragging, enableMouse, redraw;
private double xs = -2.0, xe = 1.0;
private double ys = -1.5, ye = 1.5;
private int ixs, ixe, iys, iye;
//---------------------------------------------------------
// add your code here
private void drawMandelbrot (Graphics g) {
// display boundary
curWidth = getSize().width;
curHeight = getSize().height;
System.out.println("(" + xs + "," + xe + "), (" +
ys + "," + ye + ")");
double tx0, tx, ty, r;
double dx = (xe-xs) / curWidth;
double dy = (ye-ys) / curHeight;
int n, px, py;
float curColor, prevColor = 0.0f;
enableMouse = false;
setCursor(cursorWait);
for (double y = ys; y <= ye; y += dy) {
for (double x = xs; x <= xe; x += dx) {
n = 0;
tx = ty = 0.0;
do {
tx0 = tx * tx - ty * ty;
ty = 2 * tx * ty + y;
tx = tx0 + x;
} while (tx0 < 4.0 && ++n < 256);
curColor = n / 256.0f;
if (curColor != prevColor) {
gBuffer.setColor(Color.getHSBColor(curColor,
0.8f, (1.0f - curColor * curColor)));
g.setColor(gBuffer.getColor());
prevColor = curColor;
}
px = (int) ((x - xs) / dx);
py = (int) ((y - ys) / dy);
gBuffer.drawLine(px, py, px + 1, py);
g.drawLine(px, py, px + 1, py);
}
}
setCursor(cursorCross);
enableMouse = true;
}
//---------------------------------------------------------
public void paint(Graphics g) {
update(g);
}
public void update(Graphics g) {
int newWidth = getSize().width;
int newHeight = getSize().height;
if (redraw) {
drawMandelbrot(g);
redraw = false;
} else if (imageBuffer == null || newWidth != curWidth || newHeight != curHeight) {
imageBuffer = createImage(newWidth, newHeight);
gBuffer = imageBuffer.getGraphics();
drawMandelbrot(g);
}
g.drawImage(imageBuffer, 0, 0, this);
if (isDragging) {
g.setColor(Color.white);
if (ixs < ixe) {
if (iys < iye) g.drawRect(ixs, iys, (ixe - ixs), (iye - iys));
else g.drawRect(ixs, iye, (ixe - ixs), (iys - iye));
} else {
if (iys < iye) g.drawRect(ixe, iys, (ixs - ixe), (iye - iys));
else g.drawRect(ixe, iye, (ixs - ixe), (iys - iye));
}
}
}
public void init() {
addMouseListener(this);
addMouseMotionListener(this);
cursorWait = new Cursor(Cursor.WAIT_CURSOR);
cursorCross = new Cursor(Cursor.CROSSHAIR_CURSOR);
}
public void start() {
isDragging = false;
redraw = false;
}
public void mousePressed(MouseEvent e) {
e.consume();
if (enableMouse) {
ixs = e.getX();
iys = e.getY();
}
}
public void mouseReleased(MouseEvent e) {
int tmp;
e.consume();
if (enableMouse) {
ixe = e.getX();
iye = e.getY();
if (ixs > ixe) {
tmp = ixs; ixs = ixe; ixe = tmp;
}
if (iys > iye) {
tmp = iys; iys = iye; iye = tmp;
}
isDragging = false;
// redraw the set
double dx = (xe-xs) / curWidth;
double dy = (ye-ys) / curHeight;
double tx = xs, ty = ys;
int idx = ixe - ixs;
int idy = iye - iys;
// ignore if the selected region is too small
if (idx > 10 || idy > 10) {
if (idx > idy)
iye = iys + idx;
else
ixe = ixs + idy;
xs = tx + ixs * dx;
xe = tx + ixe * dx;
ys = ty + iys * dy;
ye = ty + iye * dy;
redraw = true;
repaint();
}
}
}
public void mouseDragged(MouseEvent e) {
e.consume();
if (enableMouse) {
ixe = e.getX();
iye = e.getY();
isDragging = true;
repaint();
}
}
public void mouseEntered(MouseEvent e) {}
public void mouseExited(MouseEvent e) {}
public void mouseClicked(MouseEvent e) {}
public void mouseMoved(MouseEvent e) {}
// main method
public static void main(String[] args) {
String title = "JLab : Mandelbrot";
// set up window frame
Frame frame = new Frame(title);
frame.addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent e) {
System.exit(0);
}
}
);
Applet myApp = new Mandelbrot();
frame.add(myApp, BorderLayout.CENTER);
frame.setSize(200, 200);
frame.setVisible(true);
try {JLabIO.setWindowAlwaysOnTop(title); } catch (Error e) {}
myApp.init();
myApp.start();
}
}
|