I think I might have a problem with inheritence... I start with a base CVector class then from that I inherit to from CPoint (there are some differences between them but most everything is the same). class CPoint : public CVector Now, My CSphere class''s constructor takes this: CSphere(const CPoint &a_Centre, const float &a_Radius); but when trying to create a sphere like this I get : CNode::New(CSphere(CPoint(0,0,0),65536)); Test.cpp(18) : error C2661: ''CPoint::CPoint'' : no overloaded function takes 3 parameters I''m assuming the CVector constructor can be used that does take 3 parameters like this: CVector(float a_X, float a_Y, float a_Z); Why is CPoint unable to use CVector constuctor? Many thanks Chris

You can only rely on the base class 'no-argument' constructor, all other constructors must be written explicitly in the derived class.

The CPoint '3 argument constructor' can be very simple, using the initializer list, like so:

CPoint::CPoint (float x, float y, float z) : CVector(x, y, z)
{// no need for any code in here}

Then the constructor for CVector will be called.

Cheers

Matt





Edited by - 3dmodelman on March 10, 2001 4:00:35 AM

Thanks.. that helped a great deal...