Function _preprocess

cadquery/occ_impl/nurbs.py:358–381

Helper for handling periodicity. This function extends the knot vector, wraps the parameters and calculates the delta span.

(
    u: Array, order: int, knots: Array, periodic: bool
)

@njiti
def _preprocess(
    u: Array, order: int, knots: Array, periodic: bool
) -> Tuple[Array, Array, Optional[int], Optional[int], int]:
    """
    Helper for handling periodicity. This function extends the knot vector,
    wraps the parameters and calculates the delta span.
    """

    # handle periodicity
    if periodic:
        period = knots[-1] - knots[0]
        u_ = u % period
        knots_ext = extendKnots(order, knots)
        minspan = 0
        maxspan = len(knots) - 1
        deltaspan = order - 1
    else:
        u_ = u
        knots_ext = knots
        minspan = order
        maxspan = knots.shape[0] - order - 1
        deltaspan = 0

    return u_, knots_ext, minspan, maxspan, deltaspan


@njiti