import javax.swing.*;
import java.awt.*;
/** An instance is a turtle on a JFrame. All turtles use the same JFrame.<br><br>
A turtle is a spot on the JFrame that you can move from place
to place*/
public class Turtle {
public static JFrame jframe; // The frame in which all turtles move
private static JPanel panel; // The panel in the jframe
public static Graphics graphics;// The graphics associated with the panel
private int difference; // difference between frame and panel heights
/** The panel on which the turtle moves is of size (width, height). */
public static int width= 500;
/** The panel on which the turtle moves is of size (width, height). */
public static int height= 500;
private double x, y; // Current turtle point is (x,y)
private double angle; // Current turtle angle: 0 <= angle < 360
// 0: east, 90:north, 180: west, 270 south
private boolean penDown= true; // = "the pen is down"
private Color turtleColor= Color.black; // color of the turtle
/** Constructor: a black turtle starting at the middle of the
panel with angle 0 (looking east).
East (right) is angle 0; north (up), 90; west (left), 180;
South (down). 270. The pen is down.*/
public Turtle() {
this(width/2, height/2, 0);
}
/** Constructor: a black turtle starting at (x,y) with angle ang.
East (right) is angle 0; north (up), 90; west (left), 180;
South (down), 270. The pen is down. */
public Turtle(double x, double y, double ang) {
if (jframe == null) {
jframe= new JFrame("Turtle window");
panel= new JPanel();
panel.setPreferredSize(new Dimension(width, height));
panel.setBackground(Color.white);
jframe.getContentPane().add(panel, BorderLayout.CENTER);
jframe.pack();
jframe.setVisible(true);
graphics= panel.getGraphics();
difference= jframe.getHeight() - panel.getHeight();
pause(100);
clear();
pause(100);
}
this.x= x;
this.y= y;
angle= ang;
}
/** = the Color value for c, as follows:
1 = black, 2 = blue, 3 = cyan, 4 = dark gray, 5 = gray
6 = green, 7 = light gray, 8 = magenta, 9 = orange
10 = pink, 11 = red, 12 = white, 13 = yellow
any other integer --return black
*/
public static Color tColor(int c) {
if (c == 1) return Color.black;
if (c == 2) return Color.blue;
if (c == 3) return Color.cyan;
if (c == 4) return Color.darkGray;
if (c == 5) return Color.gray;
if (c == 6) return Color.green;
if (c == 7) return Color.lightGray;
if (c == 8) return Color.magenta;
if (c == 9) return Color.orange;
if (c == 10) return Color.pink;
if (c == 11) return Color.red;
if (c == 12) return Color.white;
if (c == 13) return Color.yellow;
return Color.black;
}
/** Set panel size as big as possible in the current window */
public void setPanelSize() {
width= jframe.getWidth();
height= jframe.getHeight()-difference;
Dimension d= new Dimension(width, height);
panel.setPreferredSize(d);
graphics= panel.getGraphics();
jframe.pack();
clear();
pause(100);
}
/** = x-coordinate of the turtle */
public double getX() {
return x;
}
/** = y-coordinate of the panel */
public double getY() {
return y;
}
/** = angle of the turtle (in degrees). East (right) is angle 0;
north (up), 90; west (left), 180; South (down), 270*/
public double getAngle() {
return angle;
}
/** = width of panel */
public int getWidth() {
return width;
}
/** = height of the panel */
public int getHeight() {
return height;
}
/** Set the angle to a degrees. East (right) is angle 0;
north (up), 90; west (left), 180; South (down), 270*/
public void setAngle(double a) {
angle= mod(a, 360);
}
/** Add a degrees to the angle */
public void addAngle(double a) {
angle= mod (angle + a, 360);
}
/** Lift pen */
public void liftPen() {
penDown= false;
}
/** Put pen down */
public void putPenDown() {
penDown= true;
}
/** Set the color of the turtle to c */
public void setColor(Color c) {
turtleColor= c;
}
/** = the current color */
public Color getColor() {
return turtleColor;
}
/** Move the turtle to (x,y), without drawing,
and face it at angle ang */
public void moveTo(double x, double y, double ang) {
Color save= graphics.getColor();
graphics.setColor(turtleColor);
this.x= x;
this.y= y;
angle= ang;
graphics.setColor(save);
}
/** Draw a circle with center at current pen position of diameter d */
public void drawCircle(double d) {
Color save= graphics.getColor();
graphics.setColor(turtleColor);
int id= (int) Math.round(d);
graphics.drawOval((int)Math.round(x-d/2), (int)Math.round(y-d/2), id, id);
graphics.setColor(save);
}
/** Fill a circle with center at current pen position of diameter d */
public void fillCircle(double d) {
Color save= graphics.getColor();
graphics.setColor(turtleColor);
int id= (int) Math.round(d);
graphics.fillOval((int)Math.round(x-d/2), (int)Math.round(y-d/2), id, id);
graphics.setColor(save);
}
/** Draw a rectangle with center at current pen position of width w, height h */
public void drawRectangle(double w, double h) {
Color save= graphics.getColor();
graphics.setColor(turtleColor);
graphics.drawRect((int)Math.round(x-w/2), (int)Math.round(y-h/2),
(int)Math.round(w), (int)Math.round(h));
graphics.setColor(save);
}
/** Fill a rectangle with center at current pen position of width w, height h */
public void fillRectangle(double w, double h) {
Color save= graphics.getColor();
graphics.setColor(turtleColor);
graphics.fillRect((int)Math.round(x-w/2), (int)Math.round(y-h/2),
(int)Math.round(w), (int)Math.round(h));
graphics.setColor(save);
}
/** Move the turtle d units in its current direction.
If the pen is down, a line will be drawn; if the pen
is up, it won't be drawn.*/
public void move(double d) {
double rAngle= (angle * Math.PI) / 180;
double newX= x + Math.cos(rAngle) * d;
double newY= y - Math.sin(rAngle) * d;
if (penDown) {
Color save= graphics.getColor();
graphics.setColor(turtleColor);
graphics.drawLine((int)Math.round(x), (int)Math.round(y),
(int)Math.round(newX), (int)Math.round(newY));
graphics.setColor(save);
}
x= newX;
y= newY;
}
/** = x mod y (for y != 0) */
private double mod(double x, double y) {
double ans= x % y;
if (ans < 0)
ans= ans + y;
return ans;
}
/** Clear the screen (make it all white) */
public void clear() {
Color c= graphics.getColor();
graphics.setColor(Color.white);
graphics.fillRect(0, 0, width, height);
graphics.setColor(c);
}
/** Pause the program for delay microseconds */
public void pause(int delay) {
try { Thread.currentThread().sleep(delay); }
catch (InterruptedException e) { }
}
}