@numericelements/knot-sequence/dist/KnotSequenceAndUtilities/fromIncreasingPeriodicToIncreasingOpenKnotSequenceCC.js

A library for generating and manipulating knot sequences for b-spline curves and surfaces

import { IncreasingOpenKnotSequenceClosedCurve } from '../IncreasingOpenKnotSequenceClosedCurve.js';
import { KnotIndexStrictlyIncreasingSequence } from '../KnotIndexStrictlyIncreasingSequence.js';
import { INCREASINGOPENKNOTSEQUENCECLOSEDCURVEALLKNOTS } from '../KnotSequenceConstructorInterface.js';
import { fromIncreasingPeriodicToStrictlyIncreasingPeriodicKnotSequence } from './fromIncreasingPeriodicToStrictlyIncreasingPeriodicKnotSequence.js';

function fromIncreasingPeriodicToIncreasingOpenKnotSequenceCC(increasingSeq) {
    const knotsOpenSequence = [];
    const multiplicityAtOrigin = increasingSeq.knotMultiplicity(new KnotIndexStrictlyIncreasingSequence(0));
    const strictlyIncSeq = fromIncreasingPeriodicToStrictlyIncreasingPeriodicKnotSequence(increasingSeq);
    const strictSeqLength = strictlyIncSeq.length();
    const lastAbscissa = strictlyIncSeq.uMax;
    let knotNumber = 1;
    for (let i = 1; i <= (increasingSeq.maxMultiplicityOrder - (multiplicityAtOrigin - 1)); i++) {
        for (let j = 0; j < strictlyIncSeq.knotMultiplicity(new KnotIndexStrictlyIncreasingSequence(strictSeqLength - 1 - i)); j++) {
            if (knotNumber <= (increasingSeq.maxMultiplicityOrder - (multiplicityAtOrigin - 1)))
                knotsOpenSequence.splice(0, 0, (strictlyIncSeq.abscissaAtIndex(new KnotIndexStrictlyIncreasingSequence(strictSeqLength - 1 - i)) - lastAbscissa));
            else
                break;
            knotNumber++;
        }
        if (knotNumber > (increasingSeq.maxMultiplicityOrder - (multiplicityAtOrigin - 1)))
            break;
    }
    for (const knot of increasingSeq) {
        if (knot !== undefined)
            knotsOpenSequence.push(knot);
    }
    knotNumber = 1;
    for (let i = 1; i <= (increasingSeq.maxMultiplicityOrder - (multiplicityAtOrigin - 1)); i++) {
        for (let j = 0; j < strictlyIncSeq.knotMultiplicity(new KnotIndexStrictlyIncreasingSequence(i)); j++) {
            if (knotNumber <= (increasingSeq.maxMultiplicityOrder - (multiplicityAtOrigin - 1))) {
                if (i === (strictSeqLength - 1)) {
                    knotsOpenSequence.push(lastAbscissa + (lastAbscissa - strictlyIncSeq.abscissaAtIndex(new KnotIndexStrictlyIncreasingSequence(0))));
                }
                else {
                    knotsOpenSequence.push(lastAbscissa + (strictlyIncSeq.abscissaAtIndex(new KnotIndexStrictlyIncreasingSequence(i)) - strictlyIncSeq.abscissaAtIndex(new KnotIndexStrictlyIncreasingSequence(0))));
                }
            }
            else
                break;
            knotNumber++;
        }
        if (knotNumber > (increasingSeq.maxMultiplicityOrder - (multiplicityAtOrigin - 1)))
            break;
    }
    return new IncreasingOpenKnotSequenceClosedCurve(increasingSeq.maxMultiplicityOrder + 1, { type: INCREASINGOPENKNOTSEQUENCECLOSEDCURVEALLKNOTS, knots: knotsOpenSequence });
}

export { fromIncreasingPeriodicToIncreasingOpenKnotSequenceCC };