class Triangulation
{
%TypeHeaderCode
#include <Triangulation.h>
%End

  public:


    //! Enumeration describing the behaviour, if two forced lines cross.
    enum forcedCrossBehaviour
    {
      SnappingType_VERTICE,  //!< the second inserted forced line is snapped to the closest vertice of the first inserted forced line.
      DELETE_FIRST,          //!< the status of the first inserted forced line is reset to that of a normal edge (so that the second inserted forced line remain and the first not)
      INSERT_VERTICE
    };

    virtual ~Triangulation();

    /**
     * Adds a line (e.g. a break-, structure- or an isoline) to the triangulation.
     * The class takes ownership of the line object and its points
     */
    virtual void addLine( Line3D* line /Transfer/, bool breakline ) = 0;

    /**
     * Adds a point to the triangulation
     * Ownership is transferred to this class
     */
    virtual int addPoint( Point3D* p ) = 0;

    /**
     * Calculates the normal at a point on the surface and assigns it to 'result'.
     * @return true in case of success and false in case of failure
     */
    virtual bool calcNormal( double x, double y, Vector3D* result ) = 0;

    /** Performs a consistency check, remove this later*/
    virtual void performConsistencyTest() = 0;

    /**
     * Calculates x-, y and z-value of the point on the surface and assigns it to 'result'.
     * Returns true in case of success and flase in case of failure
     */
    virtual bool calcPoint( double x, double y, Point3D* result ) = 0;

    /** Returns a pointer to the point with number i. Any virtual points must have the number -1*/
    virtual Point3D* getPoint( unsigned int i ) const = 0;

    /** Finds out in which triangle the point with coordinates x and y is and
     * assigns the numbers of the vertices to 'n1', 'n2' and 'n3' and the vertices to 'p1', 'p2' and 'p3'
     */
    virtual bool getTriangle( double x, double y, Point3D* p1, int* n1 /Out/, Point3D* p2 /Out/, int* n2 /Out/, Point3D* p3 /Out/, int* n3 /Out/ ) = 0;

    /** Finds out, in which triangle the point with coordinates x and y is and assigns the  points at the vertices to 'p1', 'p2' and 'p3*/
    virtual bool getTriangle( double x, double y, Point3D* p1 /Out/, Point3D* p2 /Out/, Point3D* p3 /Out/ ) = 0;

    /** Returns the number of the point opposite to the triangle points p1, p2 (which have to be on a halfedge)*/
    virtual int getOppositePoint( int p1, int p2 ) = 0;

    /** Returns the largest x-coordinate value of the bounding box*/
    virtual double getXMax() const = 0;

    /** Returns the smallest x-coordinate value of the bounding box*/
    virtual double getXMin() const = 0;

    /** Returns the largest y-coordinate value of the bounding box*/
    virtual double getYMax() const = 0;

    /** Returns the smallest x-coordinate value of the bounding box*/
    virtual double getYMin() const = 0;

    /** Returns the number of points*/
    virtual int getNumberOfPoints() const = 0;

    /**
     * Returns a pointer to a value list with the information of the triangles surrounding (counterclockwise) a point.
     * Four integer values describe a triangle, the first three are the number of the half edges of the triangle
     * and the fourth is -10, if the third (and most counterclockwise) edge is a breakline, and -20 otherwise.
     * The value list has to be deleted by the code which called the method.
     * Any virtual point needs to have the number -1
     */
    virtual QList<int>* getSurroundingTriangles( int pointno ) = 0;

    /** Returns a value list with the numbers of the four points, which would be affected by an edge swap.
     * This function is e.g. needed by NormVecDecorator to know the points,
     * for which the normals have to be recalculated.
     * The list has to be deleted by the code which calls this method
     */
    virtual QList<int>* getPointsAroundEdge( double x, double y ) = 0;

    /** Draws the points, edges and the forced lines*/
    //virtual void draw(QPainter* p, double xlowleft, double ylowleft, double xupright, double yupright, double width, double height) const=0;
    /** Sets the behaviour of the triangulation in case of crossing forced lines*/
    virtual void setForcedCrossBehaviour( Triangulation::forcedCrossBehaviour b ) = 0;
    /** Sets the color of the normal edges*/
    virtual void setEdgeColor( int r, int g, int b ) = 0;
    /** Sets the color of the forced edges*/
    virtual void setForcedEdgeColor( int r, int g, int b ) = 0;
    /** Sets the color of the breaklines*/
    virtual void setBreakEdgeColor( int r, int g, int b ) = 0;
    /** Sets an interpolator object*/
    virtual void setTriangleInterpolator( TriangleInterpolator* interpolator ) = 0;
    /** Eliminates the horizontal triangles by swapping*/
    virtual void eliminateHorizontalTriangles() = 0;
    /** Adds points to make the triangles better shaped (algorithm of ruppert)*/
    virtual void ruppertRefinement() = 0;
    /** Returns true, if the point with coordinates x and y is inside the convex hull and false otherwise*/
    virtual bool pointInside( double x, double y ) = 0;
    /** Reads the content of a taff-file*/
    //virtual bool readFromTAFF(QString fileName)=0;
    /** Saves the content to a taff file*/
    //virtual bool saveToTAFF(QString fileName) const=0;
    /** Swaps the edge which is closest to the point with x and y coordinates (if this is possible)*/
    virtual bool swapEdge( double x, double y ) = 0;
    /** Saves the triangulation as a (line) shapefile
    @return true in case of success*/
    virtual bool saveAsShapefile( const QString& fileName ) const = 0;
};