Cannot convert parameter 1 from......

Why can I not dereference this MyPolygon pointer?? It is declared here:

Code:

---

class Breakout
{
public:
        Breakout( );
        ~Breakout( );
        Ball* getBall( ) { return &ball; }

        void run( );
        void testCollisions( );


//data members
private:

        Ball ball;
        FrameRate fRate;
        MyPolygon* boundaries[ 4 ];

        void defineBoundaries( );

};

---

but when I try to dereference it here:

Code:

---

void Breakout::testCollisions( )
{
        //need to test for intersection wiht boundaries[ 0 ], the top polygon
        if( intersectPolygon( *boundaries[ 0 ], *ball.getDirection( ), 4 ) )
                cout << "HIT" << endl;
}

---

I get this error - error C2665: 'intersectPolygon' : none of the 2 overloads can convert parameter 1 from type 'class MyPolygon'

I've never seen this error before, it normally tells me what I am supposed to be converting it to - but it doesnt :(

Oh and here is theintersectPolygon() prototype if its any use:

bool intersectPolygon( MyPolygon poly, Vector3d* line );


thx in advance :)

"boundaries" is an array.
An array access like boundaries[i] is eqal to *(boundary + i), so boundaries[0] doesn't need to be dereferenced another time.
operator[] has already done it for you.

Make also sure that the derefercening of ball.getDirection() is really necessary.

Quote:

---

Originally posted by teneniel
boundaries[0] doesn't need to be dereferenced another time.
operator[] has already done it for you.

---

Wrong. Look at the declaration.

Can you post the declaration for MyPolygon?

Code:

---

class MyPolygon
{
public:

//constructors
        MyPolygon( );
        MyPolygon( const Vector3d* array, const int cornerCount );
        MyPolygon( const MyPolygon& copy );
        ~MyPolygon( );

//functions
        bool addVertex( Vector3d& vertex );
        bool removeVertex( Vector3d& vertex );
        int findVertex( Vector3d& vertex ) const;                        //finds a vertex in array and returns the index, returns -1 if not found
        Vector3d& getPoint( int index ) const;                        //returns a point from the array
        bool defaultDraw( );
        bool calcNormal( );                //generates the normal
        int getCornerCount( );
        Vector3d* getNormal( );
        void setValues( const Vector3d* array, const int cornerCount );
        Vector3d* getPoints( );

//operators
        MyPolygon& operator = ( const MyPolygon& rvalue );
        friend bool operator == ( const MyPolygon& a, const MyPolygon& b );
        friend ostream& operator << ( ostream& os, const MyPolygon& poly );


private:

//data members
        Vector3d* points;
        int corners;
        Vector3d* norm;

};

---

This is the only time I've encountered this, I've used MyPolygon objects before without trouble. Hence the confusion :confused:

Here is the entry in the msdn about this error, but I'm still no clearer....

Quote:

---

Compiler Error C2665

'function' : none of the number1 overloads can convert parameter number2 from type 'type'

The specified parameter of the overloaded function could not be converted to the required type. If you’ve encountered this error on code which compiled with an earlier version of Visual C++, please read Technote: Improved Conformance to ANSI C++ for more information.

You may need to supply a conversion operator or explicit conversion.

---

Neither am I... weird

Can you post the prototypes (both) for 'intersectPolygon'?

Code:

---

//THE ray/polygon test function
bool intersectPolygon( Vector3d* poly, Vector3d* line, int vertexCount );

//overloaded ray/polygon test function
bool intersectPolygon( MyPolygon poly, Vector3d* line );

---

If anyone is willing and able to use OpenGL and GLUT in VC++, I can send them the whole project so far.

Ahh.. finally

You are calling the function with three arguments. However, that function takes a Vector3d*, not a MyPolygon.

Thank God for that, knew it must've been something simple - it always is!

Thx for the help Sang-Drax, now to figure out why there is no collision :)