[Solved] ECS175 Project4-A SIMPLE BEZIER AND B-SPLINE CURVE EDITOR

Remark: You must NOT use GLs routines for generating Bezier or B-spline curves! You can use GL for rendering but not for evaluating these curves.

The fourth project requires the implementation of a 2D Bezier and B-spline curve editor. A 2D Bezier curve is defined as

c.

For the evaluation of a Bezier curve, use the de Casteljau algorithm to compute points on the curve. A single 2D parametric B-spline curve is defined as

c.

Remember that you do not need to evaluate the normalized B-spline basis functions. For the evaluation of a B-spline curve, use the de Boor algorithm to generate points on the curve.

When dealing with a Bezier curve, the user must be able to add, insert, delete, and modify the Bezier points bi. The same applies to a B-spline curve: The user must be able to add, insert, delete, and modify the de Boor points di. In addition to this, the user must be able to change the order k of a B-spline curve and modify the values of the knots ₀, , _n+k. Initially, you can define the order to be k = 2 and the knots to be _i = i, i = 0,,n + k.

The user must be able to specify the number of points used for rendering a Bezier or B-spline curve by a sequence of line segments (display resolution).

The user should be able to change all parameters easily by providing a screen area used for displaying and specifying the coordinates of control points (Bezier and de Boor points), the order and the knots of a B-spline curve, and the display resolution. The specification of control points should be made as easy as possible. Either the user types in the control information directly, or when modifying control points uses a rubber band technique to interactively move control points.

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The curve editor must provide a facility to store the parameters defining a Bezier or B-spline curve. The system must be capable of reading and writing control information for Bezier and B-spline curves.

It must be possible to manipulate, create, and display a scene containing multiple Bezier and multiple B-spline curves. Make it possible to select a certain curve and to operate just on the selected one!

Besides having to hand in a program listing, please prepare a manual sheet explaining how to use your program.