[SOLVED] opengl project4

Course: Instructor:
Project 4: Date due:
Computer Graphics, ECS 175, Fall Quarter 2016 Bernd Hamann
A SIMPLE BE ZIER AND B-SPLINE CURVE EDITOR
Monday, November 21, 2016
Remark: You must NOT use GLs routines for generating B ezier 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 B ezier and B-spline curve editor. A 2D B ezier curve is defined as
nn
c(t) =x(t),y(t) T = bi Bin(t) =(xi,yi)T ni (1t)niti , t[0,1].
i=0 i=0
For the evaluation of a B ezier curve, use the de Casteljau algorithm to compute points on the curve. A single 2D parametric B-spline curve is defined as
nn
c(t) =x(t), y(t) T = di Nik(t) = (xi, yi)T Nik(t) , t [k1, n+1].
i=0 i=0
Remember that you do not need to evaluate the normalized B-spline basis functions Nik(t). For the evaluation of a B-spline curve, use the de Boor algorithm to generate points on the curve.
When dealing with a B ezier curve, the user must be able to add, insert, delete, and modify the B ezier 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 knotstobei =i,i=0,,n+k.
The user must be able to specify the number of points used for rendering a B ezier 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 (B ezier 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 B ezier or B-spline curve. The system must be capable of reading and writing control infor- mation for B ezier and B-spline curves.
It must be possible to manipulate, create, and display a scene containing multiple B ezier 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 explain- ing how to use your program.
The overall grade (on a scale from 0 to 100) will depend on i) completeness (40%), ii) correctness (40%), iii) interface quality (15%), and iv) the manual sheet (5%). No project will be accepted when it is more than seven (7) days late; for each day, one (1) point will be deduced.
DO NOT REMOVE YOUR PROGRAM! YOU WILL BE ABLE TO USE IT IN THE NEXT ASSIGNMENT(S).
HAVE FUN !!!
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