Interface to Alias curve attributes.
#include <AlCurveAttributes.h> class AlCurveAttributes : public AlAttributes virtual AlObjectType type() const; AlObject* copyWrapper() const; curveFormType form() const; int degree() const; int numberOfSpans() const; int numberOfCVs() const; statusCode CVsUnaffectedPosition( double[][4], int[] ) const; int numberOfKnots() const; statusCode knotVector( double[] ) const;
AlCurveAttributes is a class derived from the AlAttributes class. This class allows access to a curve.
This class provides information similar to that of the AlCurve class but without the ability to modify the curve or its CVs.
NOTE: When an AlCurve has just an AlCurveAttribute attribute, the AlCurveAttribute provides no information that the AlCurve doesn’t. For this reason, in this case, no information is provided by the AlCurveAttribute, and all methods return null values.
Returns the class identifier ’kCurveAttributeType’.
Makes a copy of the AlAttribute. The returned AlAttribute will reference the same data as the original.
When a curve is periodic it means that its endpoints are coincident and that the curve is tangent continuous at the point where its endpoints touch. "kPeriodic" is returned in this case. "kClosed" is returned if the curve is not periodic, but if its endpoints are coincident. If a curve is neither "kPeriodic" nor "kClosed" then "kOpen" is returned. (Note: If you use the "close" menu item in the interactive Alias package, you actually make a curve periodic.)
kOpen - the curve is open
kClosed - the curve is closed
kPeriodic - the curve is periodic
kInvalidCurve - the attribute is not valid
Returns the degree of the curve. Zero will be returned if the attribute is not valid.
Returns the number of spans in the curve. -1 is returned if the attribute is not valid.
Returns the number of CVs. -1 is returned if the attribute is not valid.
Returns the CVs in the given CV array and the multiplicity of each CV in the multiplicity vector. The first dimension of the CV array must be numberOfCVs(). The length of the multiplicity vector must also be numberOfCVs(). The multiplicity vector returned by this function is the same as the one returned by CVsWorldPosition().
> CVList - returned CVs
> mult - multiplicity of each CV
sSuccess - the CVs’ unaffected position was successfully returned
sInvalidObject - the attribute is not valid
sInvalidArgument - one or both of the arguments were NULL
sFailure - the position was not returned
Returns the number of knots in this curve. For more information as to what this number means, see the description for the create() method. -1 will be returned if the attribute is not valid.
Returns the knot vector in the given vector. This vector must be of length numberOfKnots(). For more information about what these values mean, see the description for the AlCurve::create() method in AlCurve.
> knotVector - returned knot vector
sSuccess - the knot vector was successfully returned
sInvalidObject - the attribute is not valid
sInvalidArgument - one or both of the arguments was NULL
sFailure - the knot vector could not be returned