/*
	Test program for C code from An Introduction to NURBS
	by David F. Rogers. Copyright (C) 2000 David F. Rogers,
	All rights reserved.
	
	Name: tbasis.c
	Purpose: Test the open uniform basis function
	Language: C
	Subroutines called: knot.c, basis.c
	Book reference: Section 3.4, Ex. 3.2, p. 55
*/

#include 	<stdio.h>

main()
{
	int i;
	int c,npts,nplusc;
	int x[22];
	float t;
	float n[20];
	float sum;


	printf("Input number of polygon points and order separated by a space npts c ");
	scanf("%d %d",&npts,&c);

	t = 0.;

	nplusc = npts + c;

	knot(npts,c,x);
		printf("The knot vector is ");
		for (i = 1; i <= nplusc; i++){
			printf(" %d ", x[i]);
		}
		
	printf("\n");
	
	while(( t >= 0.) && (t <= (float)x[nplusc])){
		printf("Input the parameter value t (Control C to end) ");
		scanf("%f", &t);
		printf("t = ");
		printf("%f\n",t);
		basis(c,t,npts,x,n);
		printf("Basis function is ");
		sum = 0;
		for (i = 1; i <= npts; i++){
			sum = sum + n[i];
		}
		for (i = 1; i <= npts; i++){
			printf("%f ", n[i]);
		}
		printf("\n");
		printf("Sum of the Basis functions is %f \n",sum);
		printf("\n");
	}
	printf("t is outside the parameter range, program ends \n");
}