ObjectARX Reference Guide > AcDb Classes > AcDbCurve Class > AcDbCurve Methods
AcDbCurve Methods
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Methods
Method 
Description 
 
This function returns with area set to the area inside the curve. For the AutoCAD built-in classes, the curve must lie on a plane. If the curve is not closed, its start and end points are considered as connected by a line segment that closes it.
Returns Acad::eOk if successful. For the AutoCAD built-in classes, Acad::eInvalidInput is returned if the curve is not planar. Other return values are possible for custom entity classes depending on how they were implemented.
This function must be able to calculate a bounded area value for the curve.
While the AutoCAD built-in classes require the... more 
 
Calculates the length of the curve's segment from the curve's start point to the point specified by param.
Returns Acad::eOk if successful, or Acad::eInvalidInput if param is out of range. For other errors, the implementer must decide what return value to use. See the acdb.h header file for possible ErrorStatus values.
In the default implementation, the function returns Acad::eNotImplemented.
 
The implementation of this function in derived classes should return with endParam set to the parameter of the endpoint of the curve.
Returns Acad::eOk if successful.
By default, the function returns Acad::eNotImplemented.
 
Calculates the length of the curve's segment between the curve's start point and point and returns the length in distance.
Returns Acad::eOk if successful, or Acad::eInvalidInput if the point is not on the curve. For other errors, the implementer must decide what return value to use. See the acdb.h header file for possible ErrorStatus values.
Returns Acad::eNotImplemented in the default implementation.
 
In this class and in derived classes, this function returns with endPoint set to the end point (in WCS coordinates) of the curve.
Returns Acad::eOk if successful.
The default implementation returns Acad::eNotImplemented.
 
 
This function creates one or more entities that together make up the result of offsetting the curve by the distance offsetDist. For many curves, the result is a single new curve. (This single new curve may not be of the same class as the original curve. For example, offsetting an AcDbEllipse results in an AcDbSpline, since the result of offsetting an ellipse does NOT fit the equation of an ellipse.)
In some cases, it might be necessary for the offset result to be several curves. (The result may even be several curves that would form a single curve... more 
This function creates one or more entities that, together, make up the result of offsetting the curve by the distance offsetDist in the plane with normal vector normal. For many curves, the result will be a single new curve, which may not be of the same class as the original curve. For example, offsetting an AcDbEllipse results in an AcDbSpline, since the result of offsetting an ellipse does not fit the equation of an ellipse. However, in some cases it might be necessary for the offset result to be several curves. To allow for this possibility, a dynamic... more 
This function creates a new curve entity that is the result of projecting the curve along the projPlane's normal onto the projPlane and sets projCurve to point to the newly created curve. projCurve is declared as type AcDbCurve to allow the returned curve to be any class derived from AcDbCurve (for example, when an AcDbArc is projected onto a plane, the result is an AcDbEllipse).
The returned curve is dynamically allocated, but has not been added to an AcDbDatabase yet. So, the application that calls this function is responsible for its memory. If the curve is subsequently appended... more 
This function determines the parameter of the curve at the location that is a distance of dist along the curve from the curve start, and returns the parameter in param.
Returns Acad::eOk if successful. If dist is not valid for the curve, then Acad::eInvalidInput is returned. Other ErrorStatus return values are implementation-dependent.
The default implementation returns Acad::eNotImplemented.
 
This function determines the parameter of the curve at point and returns the parameter in param.
Returns Acad::eOk if successful. If point is not on the curve, then Acad::eInvalidInput is returned. Other ErrorStatus return values are implementation-dependent.
Acad::eNotImplemented is returned by the default implementation.
 
This function determines the point on the curve that is a distance of dist along the curve from the curve start, and returns the point in point. point is in WCS coordinates.
Returns Acad::eOk if successful. If dist is not valid for the curve, then Acad::eInvalidInput is returned. Other ErrorStatus return values are implementation-dependent.
The default implementation returns Acad::eNotImplemented.
 
This function determines the point on the curve that corresponds to the param parameter, and returns the point in point. point is in WCS coordinates.
Returns Acad::eOk if successful. If the parameter is not within the curve's range, then Acad::eInvalidInput is returned. Other ErrorStatus return values are implementation-dependent.
Returns Acad::eNotImplemented in the default implementation.
 
 
This function creates a new curve entity that is the result of projecting the curve parallel to projDir onto the projPlane and sets projCurve to point to the newly created curve. projCurve is declared as type AcDbCurve in order to allow the returned curve to be any class derived from AcDbCurve. For example, when an AcDbArc is projected onto a plane, the result is an AcDbEllipse.
The returned curve is dynamically allocated, but has not been added to an AcDbDatabase yet. The application that calls this function is therefore responsible for its memory. If the curve is subsequently... more 
This function creates a new AcDbSpline entity, sets it to be as close an approximation as possible to the curve, and then returns with spline pointing to the newly created spline entity.
The returned spline is dynamically allocated, but has not been added to an AcDbDatabase yet. So, the application that calls this function is responsible for its memory. If the spline is subsequently appended to a database, then the database takes over responsibility for its memory. Otherwise, the application is responsible for deleting it when it is no longer needed.
Returns Acad::eOk if successful. If there is an error... more 
 
This function returns with startParam set to the start parameter on the curve.
Returns Acad::eOk if successful.
Returns Acad::eNotImplemented in the default implementation.
 
This function returns with startPoint set to the start point (in WCS coordinates) of the curve.
Returns Acad::eOk if successful, and Acad::eNotImplemented in the default implementation.
 
This function returns Adesk::kTrue if, and only if, the curve is closed; that is, its start point is identical to its end point. Otherwise, it returns Adesk::kFalse.
Returns Acad::kFalse in the default implementation.
 
Reverses the parameterization of the curve. The start becomes the end and visa versa. 
This function returns Adesk::kTrue if, and only if, the curve has an infinite range in both directions and there is a period value T such that there is a point on curve at (u + T) = point on curve (u), for any parameter u. If the curve is not periodic, then Adesk::kFalse is returned.
The default implementation returns Adesk::kFalse.