CS335
Fall, 2008
Programming Assignment 3 (40 points)
(Team project: two people a team)
Due: December 11 (Thursday)


1. Problem Description

In this assignment you are required again to form a team with a
classmate and jointly develop java tools that allow a user to
perform 2D animation of a 2D polygon and the associated Bezier
curve on screen. A new menu item called

should be added to your menu list for Prog2 so that once a polygon
is input, the user can click in this area to start the animation
of the polygon and the associated Bezier curve.



2. Implementation Details


For a given polygon, we can create a closed composite Bezier
curve in two steps:

    (1) compute mid-point of each edge of the polygon;
    (2) for each vertex of the polygon, construct a Bezier
        curve of degree two using the vertex and mid-points
        of the adjacent edges as control points.

For instance, in (a) of the above figure, D is the mid-point
of the edge AB and E is the mid-point of the edge BC.
The Bezier curve segment defined by the mid-points D and
E and the polygon vertex B is shown in (b).
The equation of such a curve is shown below.

When the "Animated 2D bouncing" menu item is clicked by the user,
your program should construct a closed, composite Bezier curve of
degree two for the given polygon using the above approach first.

With a pre-set velocity (direction and speed) and a rotation speed
about its centroid (of the polygon), your program should then move
and rotate the polygon and the Bezier curve accordingly and bounce
them in the appropriate direction when the polygon and the Bezier
curve hit the wall (boundary of the canvas or your drawing area)


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HERE IS THE IMPORTANT PART
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Your program should not bounce the polygon and the Bezier curve
immediately after one of the vertices touches the wall. Your
program will start to bounce the polygon and the Bezier curve
only when the "centroid" of the polygon hits the wall.

This means that your program will need to clip the polygon
against the wall periodically and update the corresponding
Bezier curve accordingly. At some point, both the polygon
and the associated Bezier curve might be broken into several
smaller, disjoint polygons and Bezier curves.



3. What to Turn In

Mail your program (in one file) and external documentation (in another
file) of your team to the grader on or before the due date.  Name your
applet driver "Draw.java" and put it in the first (comment) line of the
driver. The names of the other classes of your program are not important.
Your java code must contain internal documentation.  The external
documentation named YourLastNames.txt should describe the project
specifications and the implementation details.