#include <knotvector.h>

Public Member Functions
	Knotvector (void)

	~Knotvector (void)

void	init (long, long, long, INREAL *)

int	validate (void)

void	show (const char *)

Public Attributes
long	order

long	knotcount

long	stride

Knot *	knotlist

Detailed Description

Definition at line 41 of file knotvector.h.

Constructor & Destructor Documentation

◆ Knotvector()

Knotvector::Knotvector ( void )

Definition at line 62 of file knotvector.cc.

{
    knotcount = 0;
    stride = 0;
    order = 0;
    knotlist = 0;
}

◆ ~Knotvector()

Knotvector::~Knotvector ( void )

Definition at line 70 of file knotvector.cc.

{
    if( knotlist ) delete[] knotlist;
}

Member Function Documentation

◆ init()

void Knotvector::init	(	long	_knotcount,
		long	_stride,
		long	_order,
		INREAL *	_knotlist
	)

Definition at line 50 of file knotvector.cc.

{
    knotcount = _knotcount;
    stride = _stride;
    order = _order;
    knotlist = new Knot[_knotcount];
    assert( knotlist != 0 );
 
    for( int i = 0; i != _knotcount; i++ )
    knotlist[i] = (Knot) _knotlist[i];
}

Referenced by NurbsTessellator::nurbscurve(), and NurbsTessellator::nurbssurface().

◆ show()

void Knotvector::show ( const char * msg )

Definition at line 132 of file knotvector.cc.

{
#ifndef NDEBUG
    _glu_dprintf( "%s\n", msg );
    _glu_dprintf( "order = %ld, count = %ld\n", order, knotcount );
 
    for( int i=0; i<knotcount; i++ )
    _glu_dprintf( "knot[%d] = %g\n", i, knotlist[i] );
#endif
}

Referenced by NurbsTessellator::do_check_knots().

◆ validate()

int Knotvector::validate ( void )

Definition at line 75 of file knotvector.cc.

{
   /* kindex is used as an array index so subtract one first,
     * this propagates throughout the code so study carefully */
    long    kindex = knotcount-1;
 
    if( order < 1 || order > MAXORDER ) {
    // spline order un-supported
    return( 1 );
    }
 
    if( knotcount < (2 * order) ) {
    // too few knots
    return( 2 );
    }
 
    if( identical( knotlist[kindex-(order-1)], knotlist[order-1]) ) {
    // valid knot range is empty
    return( 3 );
    }
 
    for( long i = 0; i < kindex; i++)
    if( knotlist[i] > knotlist[i+1] ) {
        // decreasing knot sequence
        return( 4 );
    }
        
    /* check for valid multiplicity */
 
    /*  kindex is currently the index of the last knot.
     *  In the next loop  it is decremented to ignore the last knot
     *  and the loop stops when kindex  is 2 so as to ignore the first
     *  knot as well.  These knots are not used in computing
     *  knot multiplicities.
     */
 
    long multi = 1;
    for( ; kindex >= 1; kindex-- ) {
    if( knotlist[kindex] - knotlist[kindex-1] < TOLERANCE ) {
        multi++;
        continue;
    }
    if ( multi > order ) {
        // knot multiplicity greater than order of spline
        return( 5 );
    }
    multi = 1;
    }
 
    if ( multi > order ) {
    // knot multiplicity greater than order of spline
    return( 5 );
    }
 
    return 0;
}

Referenced by NurbsTessellator::do_check_knots().

Member Data Documentation

◆ knotcount

long Knotvector::knotcount

Definition at line 49 of file knotvector.h.

Referenced by init(), Knotvector(), Splinespec::kspecinit(), show(), and validate().

◆ knotlist

Knot* Knotvector::knotlist

Definition at line 51 of file knotvector.h.

Referenced by init(), Knotvector(), Splinespec::kspecinit(), show(), validate(), and ~Knotvector().

◆ order

long Knotvector::order

Definition at line 48 of file knotvector.h.

Referenced by Splinespec::kspecinit().

◆ stride

long Knotvector::stride

Definition at line 50 of file knotvector.h.