ts::BSpline ts::BSpline::buckle(const ts::rational b) const
{
ts::BSpline bs;
const tsError err = ts_bspline_buckle(&bspline, b, &bs.bspline);
if (err < 0)
throw std::runtime_error(ts_enum_str(err));
return bs;
}
void display(void)
{
size_t i;
tsBSpline buckled;
tsReal *ctrlp, *knots;
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
ts_bspline_buckle(&spline, b, &buckled, NULL);
/* draw buckled */
ts_bspline_control_points(&buckled, &ctrlp, NULL);
ts_bspline_knots(&buckled, &knots, NULL);
glColor3f(1.0, 1.0, 1.0);
glLineWidth(3);
gluBeginCurve(theNurb);
gluNurbsCurve(
theNurb,
(GLint)ts_bspline_num_knots(&buckled),
knots,
(GLint)ts_bspline_dimension(&buckled),
ctrlp,
(GLint)ts_bspline_order(&buckled),
GL_MAP1_VERTEX_3
);
gluEndCurve(theNurb);
/* draw control points */
glColor3f(1.0, 0.0, 0.0);
glPointSize(5.0);
glBegin(GL_POINTS);
for (i = 0; i < ts_bspline_num_control_points(&buckled); i++)
glVertex3fv(&ctrlp[i * ts_bspline_dimension(&buckled)]);
glEnd();
ts_bspline_free(&buckled);
free(ctrlp);
free(knots);
b -= 0.001f;
if (b < 0.f)
b = 1.f;
glutSwapBuffers();
glutPostRedisplay();
}