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Volumes and 3D Finite Elements

We have introduced the class Triang3d in order to describe the shapes of domains in the dimension three.

#CLASS Triang3d : Root {
        int number_of_points;
        int max_number_of_points;
        double *x, *y, *z;    /* point-coordinates */ 
        int number_of_elements;
        int max_number_of_elements;
        INT4 *vertex;        /* vertex indices of all tetrahedron */
        INT4 *neighbour;     /* neighbour tetrahedron */
                             /* neighbour[j][i] is opposite to vertex[j][i] */
        int data_is_borrowed;
};

In order to employ finite elements a subclass Fe3d of Triang3d need to be introduced.

#CLASS Fe3d : Triang3d {
        int dimension_of_value; /* 1==scalar,  >1 => vector function     */
        int polynomial_order;   /* 1==linear, 2==quadratic,... elements  */
        void (*f)(struct fe3d *, int, VEC4, double*);
                                /* void *f( FE3D *fe, int triangle, 
                                            VEC4 barycentric_coordinates,
                                            double value[dim] )          */

        /* optional ******************************************************/
        int size_of_data;      /* size of user data                      */
        char *data;            /* and pointer to it                      */
        /* ***************************************************************/
};

Now let us specify for each method the message passing, the delivering of arguments and the return value. We will also describe briefly the method itself. (Note: There will occur methods working on instances of Scene. At the first scene node the object is a Fe3d instance registered and the following next_scene node contains the inserted instance after the return from the actual method.)

SFB 256 Universität Bonn and IAM Universität Freiburg