/* nag_mesh2d_bound (d06bac) Example Program. 
 *
 * Copyright 2001 Numerical Algorithms Group.
 *
 * Mark 7, 2001. 
 */

#include <stdio.h>
#include <nag.h>
#include <nag_stdlib.h>
#include <nagd06.h>

/* Structure to allow data to be passed into */
/* the user-supplied function fbnd */

struct user
{
  /* details of the ellipse containing the NAG logo */

  double xa, xb, x0, y0;
};

static double fbnd(Integer , double , double , Nag_Comm *);

#define EDGE(I,J) edge[3*((J)-1)+(I)-1]
#define LINED(I,J) lined[4*((J)-1)+(I)-1]
#define CONN(I,J) conn[3*((J)-1)+(I)-1]
#define COOR(I,J) coor[2*((J)-1)+(I)-1]
#define COORCH(I,J) coorch[2*((J)-1)+(I)-1]
#define COORUS(I,J) coorus[2*((J)-1)+(I)-1]


int main(int argc, char* argv[])
{
  const Integer nus=4, nvmax=1000, nedmx=300, nvint=0;
  struct user ellipse;
  Nag_Comm comm;
  double x0, xa, xb, xmax, xmin, y0, ymax, ymin;
  Integer exit_status, i, itrace, j, k, ncomp, nedge, nelt, nlines,
    npropa, nv, nvb, reftk, l;
  NagError fail;
  char pmesh[2];
  double *coor=0, *coorch=0, *coorus=0, *rate=0, *weight=0;
  Integer *conn=0, *edge=0, *lcomp=0, *lined=0,
    *nlcomp=0;

  INIT_FAIL(fail);
  exit_status = 0;

  Vprintf(" d06bac Example Program Results\n\n");

  /* Skip heading in data file */
    
  Vscanf("%*[^\n] ");

  /* Initialise boundary mesh inputs: */
  /* the number of line and of the characteristic points of */
  /* the boundary mesh */

  Vscanf("%ld%*[^\n] ", &nlines);

  /* Allocate memory */

  if ( !(coor = NAG_ALLOC(2*nvmax, double)) ||
       !(coorch = NAG_ALLOC(2*nlines, double)) ||
       !(coorus = NAG_ALLOC(2*nus, double)) ||
       !(rate = NAG_ALLOC(nlines, double)) ||
       !(weight = NAG_ALLOC(1, double)) ||
       !(conn = NAG_ALLOC(3*(2*nvmax+5), Integer)) ||
       !(edge = NAG_ALLOC(3*nedmx, Integer)) ||
       !(lined = NAG_ALLOC(4*nlines, Integer)) ||
       !(lcomp = NAG_ALLOC(nlines, Integer)) )
    {
      Vprintf("Allocation failure\n");
      exit_status = -1;
      goto END;
    }

  /* The ellipse boundary which envelops  */
  /* the NAG Logo, the N, the A and the G */

  for (j = 1; j <= nlines; ++j) Vscanf("%lf", &COORCH(1,j));    
  Vscanf("%*[^\n] ");

  for (j = 1; j <= nlines; ++j) Vscanf("%lf", &COORCH(2,j));
  Vscanf("%*[^\n] ");

  for (j = 1; j <= nus; ++j) Vscanf("%lf", &COORUS(1,j));
  Vscanf("%*[^\n] ");

  for (j = 1; j <= nus; ++j) Vscanf("%lf", &COORUS(2,j));
  Vscanf("%*[^\n] ");

  /* The lines of the boundary mesh */

  for (j = 1; j <= nlines; ++j)
    {
      for (i = 1; i <= 4; ++i) Vscanf("%ld", &LINED(i,j));
      Vscanf("%lf", &rate[j-1]);
    }
  Vscanf("%*[^\n] ");

  /* The number of connected components  */
  /* to the boundary and their information */

  Vscanf("%ld%*[^\n] ", &ncomp);

  /* Allocate memory */

  if (!(nlcomp = NAG_ALLOC(ncomp, Integer)) )
    {
      Vprintf("Allocation failure\n");
      exit_status = -1;
      goto END;
    }

  j = 0;
  for (i = 0; i < ncomp; ++i)
    {
      Vscanf("%ld", &nlcomp[i]);        
      Vscanf("%*[^\n] ");
      l = j + abs(nlcomp[i]);

      for (k = j; k < l; ++k) Vscanf("%ld", &lcomp[k]);
      Vscanf("%*[^\n] ");

      j += abs(nlcomp[i]);
    }
    
  Vscanf(" ' %1s '%*[^\n] ", pmesh);

  /* Data passed to the user-supplied function */

  xmin = COORCH(1, 4);
  xmax = COORCH(1, 2);
  ymin = COORCH(2, 1);
  ymax = COORCH(2, 3);

  xa = (xmax-xmin)/2.0;
  xb = (ymax-ymin)/2.0;

  x0 = (xmin+xmax)/2.0;
  y0 = (ymin+ymax)/2.0;

  comm.p = (Pointer)&ellipse;

  ellipse.xa = xa;
  ellipse.xb = xb;
  ellipse.x0 = x0;
  ellipse.y0 = y0;

  itrace = -1;

  /* Call to the boundary mesh generator */

  d06bac(nlines, coorch, lined, fbnd, coorus, nus, rate, ncomp, nlcomp, 
         lcomp, nvmax, nedmx, &nvb, coor, &nedge, edge, itrace, 0, 
         &comm, &fail);

  if (fail.code == NE_NOERROR)
    {
      if (pmesh[0] == 'N')
        {
          Vprintf(" Boundary mesh characteristics\n");
          Vprintf(" nvb   =%6ld\n", nvb);
          Vprintf(" nedge =%6ld\n", nedge);
        }
      else if (pmesh[0] == 'Y')
        {

          /* Output the mesh to view it using the NAG Graphics Library */

          Vprintf(" %10ld%10ld\n", nvb, nedge);

          for (i = 1; i <= nvb; ++i) 
             Vprintf("  %4ld  %12.6e  %12.6e  \n", 
                     i, COOR(1,i), COOR(2,i));

          for (i = 1; i <= nedge; ++i)
            Vprintf(" %4ld%4ld%4ld%4ld\n", 
               i, EDGE(1,i), EDGE(2,i), EDGE(3,i));
        }
      else
        {
          Vprintf("Problem with the printing option Y or N\n");
          exit_status = -1;
          goto END;
        }
    }
  else
    {
      Vprintf("Error from d06bac.\n%s\n", fail.message);
      exit_status = 1;
      goto END;
    }

  /* Initialise mesh control parameters */

  itrace = 0;
  npropa = 1;

  /* Call to the 2D Delaunay-Voronoi mesh generator */

  d06abc(nvb, nvint, nvmax, nedge, edge, &nv, &nelt, coor, conn,
         weight, npropa, itrace, 0, &fail);

  if (fail.code == NE_NOERROR)
    {
      if (pmesh[0] == 'N')
        {
          Vprintf(" Complete mesh characteristics (Delaunay-Voronoi)\n");
          Vprintf(" nv   =%6ld\n", nv);
          Vprintf(" nelt =%6ld\n", nelt);
        }
      else if (pmesh[0] == 'Y')
        {
          /* Output the mesh to view it using the NAG Graphics Library */

          Vprintf(" %10ld%10ld\n", nv, nelt);

          for (i = 1; i <= nv; ++i) 
              Vprintf("  %12.6e  %12.6e  \n", COOR(1,i), COOR(2,i));

          reftk = 0;
          for (k = 1; k <= nelt; ++k) 
              Vprintf(" %10ld%10ld%10ld%10ld\n", 
                   CONN(1,k), CONN(2,k), CONN(3,k), reftk);
        }
      else
        {
          Vprintf("Problem with the printing option Y or N\n");
          exit_status = -1;
          goto END;
        }
    }
  else
    {
      Vprintf("Error from d06abc.\n%s\n", fail.message);
      exit_status = 1;
      goto END;
    }

  /* Call to the 2D Advancing front mesh generator */

    d06acc(nvb, nvint, nvmax, nedge, edge, &nv, &nelt, coor, 
           conn, weight, itrace, 0, &fail);

  if (fail.code == NE_NOERROR)
    {
      if (pmesh[0] == 'N')
        {
          Vprintf(" Complete mesh characteristics (Advancing Front)\n");
          Vprintf(" nv   =%6ld\n", nv);
          Vprintf(" nelt =%6ld\n", nelt);
        }
      else if (pmesh[0] == 'Y')
        {
          /* Output the mesh to view it using the NAG Graphics Library */

          Vprintf(" %10ld%10ld\n", nv, nelt);

          for (i = 1; i <= nv; ++i) 
              Vprintf("  %12.6e  %12.6e  \n", 
                      COOR(1,i), COOR(2,i));

          reftk = 0;
          for (k = 1; k <= nelt; ++k) 
              Vprintf(" %10ld%10ld%10ld%10ld\n", 
                     CONN(1,k), CONN(2,k), CONN(3,k), reftk);
        }
      else
        {
          Vprintf("Problem with the printing option Y or N\n");
          exit_status = -1;
          goto END;
        }
    }
  else
    {
      Vprintf("Error from d06acc.\n%s\n", fail.message);
      exit_status = 1;
      goto END;
    }

 END:
  if (coor) NAG_FREE(coor);
  if (coorch) NAG_FREE(coorch);
  if (coorus) NAG_FREE(coorus);
  if (rate) NAG_FREE(rate);
  if (weight) NAG_FREE(weight);
  if (conn) NAG_FREE(conn);
  if (edge) NAG_FREE(edge);
  if (lcomp) NAG_FREE(lcomp);
  if (lined) NAG_FREE(lined);
  if (nlcomp) NAG_FREE(nlcomp);

  return exit_status;
}

static double fbnd(Integer i, double x, double y, Nag_Comm *pcomm)
{
  double ret_val, d1, d2;
  double radius2, x0, xa, xb, y0;
  struct user *ellipse = (struct user *)pcomm->p;

  xa = ellipse->xa;
  xb = ellipse->xb;
  x0 = ellipse->x0;
  y0 = ellipse->y0;

  ret_val = 0.0;

  switch(i)
    {
    case 1:

      /* line 1,2,3, and 4: ellipse centred in (X0,Y0) with */
      /* XA and XB as coefficients */

      d1 = (x - x0)/xa;
      d2 = (y - y0)/xb;

      ret_val = d1*d1 + d2*d2 - 1.0;
      break;

    case 2:

      /* line 24, 27, 33 and 38 are a circle centred in (X0,Y0) */
      /* with radius SQRT(RADIUS2) */

      x0 = 20.5;
      y0 = 4.0;
      radius2 = 4.25;

      d1 = x - x0;
      d2 = y - y0;

      ret_val = d1*d1 + d2*d2 - radius2;
      break;
    
    case 3:

      x0 = 17.0;
      y0 = 8.5;
      radius2 = 5.0;

      d1 = x - x0;
      d2 = y - y0;

      ret_val = d1*d1 + d2*d2 - radius2;
      break;

    case 4:

      x0 = 17.0;
      y0 = 8.5;
      radius2 = 5.0;

      d1 = x - x0;
      d2 = y - y0;

      ret_val = d1*d1 + d2*d2 - radius2;
      break;

    case 5:

      x0 = 19.5;
      y0 = 4.0;
      radius2 = 1.25;

      d1 = x - x0;
      d2 = y - y0;

      ret_val = d1*d1 + d2*d2 - radius2;
      break;

    default:
      break;
    }

  return ret_val;
}