Irregular polygon program

[shihaoran]

Thx for the help for my other two programs.

Here is a hard one; it is about makeing irregular polygon; i could not figure it out, help pls....

1. Implement a class IrregularPolygo n that contains an array list of Point2D.Double objects.

2. The Point2D.Double class defines a point specified in double precision representing a location in (x, y) coordinate space. For example, Point2D.Double( 2.5, 3.1) constructs and initializes a point at coordinates (2.5, 3.1).

3. Use the following declarations as a starting point for your lab work.

import java.awt.geom.* ; // for Point2D.Double
import java.util.Array List; // for ArrayList
import gpdraw.*; // for DrawingTool

public class IrregularPolygo n{
private ArrayList <Point2D.Double > myPolygon;

// constructors
public IrregularPolygo n() { }

// public methods
public void add(Point2D.Dou ble aPoint) { }

public void draw() { }

public double perimeter() { }

public double area() { }
}

[sicarie]

Thx for the help for my other two programs.

Here is a hard one; it is about makeing irregular polygon; i could not figure it out, help pls....

1. Implement a class IrregularPolygo n that contains an array list of Point2D.Double objects.

2. The Point2D.Double class defines a point specified in double precision representing a location in (x, y) coordinate space. For example, Point2D.Double( 2.5, 3.1) constructs and initializes a point at coordinates (2.5, 3.1).

3. Use the following declarations as a starting point for your lab work.

import java.awt.geom.* ; // for Point2D.Double
import java.util.Array List; // for ArrayList
import gpdraw.*; // for DrawingTool

public class IrregularPolygo n{
private ArrayList <Point2D.Double > myPolygon;

// constructors
public IrregularPolygo n() { }

// public methods
public void add(Point2D.Dou ble aPoint) { }

public void draw() { }

public double perimeter() { }

public double area() { }
}

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MODERATOR

[r035198x]

Changed thread title.

[ItachiOwnage]

Hey, im new to the forums.....anyw ays, I'm doing the same problem stated above but I'm having a tough time starting the program because the drawingtool code slipped my mind. I can't seem to find it on java.sun.....
can anyone show me how to declare the sketchpad and pencil? The main thing I can't remember is where i place it in the driver or a function?

Thanks for the help.

[JosAH]

A Graphics object (the thing you draw on) even has a drawPolygon method so
that part is easy. The perimeter of a polygon is simply the sum of the lengths
of the line segments.

The area can be calculated in a simple way if the polygon doesn't intersect itself,
otherwise quite a bit of 101 geometry fiddling has to be performed.

kind regards,

Jos