class wcPt3D 
   {
      private:
         GLfloat x, y, z;

      public:
      /*  Default Constructor: 
       *  Initialize position as (0.0, 0.0, 0.0).  
       */
      wcPt3D ( ) {
         x = y = z = 0.0;
      }

      setCoords (GLfloat xCoord, GLfloat yCoord, GLfloat zCoord) {
         x = xCoord;
         y = yCoord;
         z = zCoord;
      }

      GLfloat getx ( ) const {
         return x;
      }

      GLfloat gety ( ) const {
         return y;
      }

      GLfloat getz ( ) const {
         return z;
      }
   };

   typedef float Matrix4x4 [4][4];

   void scale3D (GLfloat sx, GLfloat sy, GLfloat sz, wcPt3D fixedPt)
   {
      Matrix4x4 matScale3D;

      /*  Initialize scaling matrix to identity.  */
      matrix4x4SetIdentity (matScale3D);

      matScale3D [0][0] = sx;
      matScale3D [0][3] = (1 - sx) * fixedPt.getx ( );
      matScale3D [1][1] = sy;
      matScale3D [1][3] = (1 - sy) * fixedPt.gety ( );
      matScale3D [2][2] = sz;
      matScale3D [2][3] = (1 - sz) * fixedPt.getz ( );
   }