/* GTS - Library for the manipulation of triangulated surfaces
 * Copyright (C) 1999 Stphane Popinet
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	 See the GNU
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public
 * License along with this library; if not, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 */

#include <math.h>
#include <stdlib.h>
#include "gts.h"

int main (int argc, char * argv[])
{
  guint i, j, nx, ny;
  gdouble cosa, sina, noise;
  GtsSurface * surface;
  GSList * l, * vertices = NULL;
  GtsTriangle * t;
  GtsVertex * v1, * v2, * v3;

  if (argc != 5) {
    fprintf (stderr, "usage: cartesian nx ny angle noise\n");
    return 1;
  }

  nx = atoi (argv[1]);
  ny = atoi (argv[2]);
  cosa = cos (atof (argv[3]));
  sina = sin (atof (argv[3]));
  noise = atof (argv[4]);
  
  for (i = 0; i < nx; i++) {
    gdouble x = (gdouble) i/(gdouble) (nx - 1); 
    for (j = 0; j < ny; j++) {
      gdouble y = (gdouble) j/(gdouble) (nx - 1); 
      vertices = g_slist_prepend (vertices, 
		   gts_vertex_new (gts_vertex_class (),
				   cosa*x - sina*y, 
				   sina*x + cosa*y,
				   noise*rand()/(gdouble) RAND_MAX));
    }
  }

  t = gts_triangle_enclosing (gts_triangle_class (), vertices, 100.);
  gts_triangle_vertices (t, &v1, &v2, &v3);
  surface = gts_surface_new (gts_surface_class (),
			     gts_face_class (),
			     gts_edge_class (),
			     gts_vertex_class ());
  gts_surface_add_face (surface, gts_face_new (gts_face_class (),
					       t->e1, t->e2, t->e3));
  l = vertices;
  while (l) {
    g_assert (gts_delaunay_add_vertex (surface, l->data, NULL) == NULL);
    l = l->next;
  }

  gts_allow_floating_vertices = TRUE;
  gts_object_destroy (GTS_OBJECT (v1));
  gts_object_destroy (GTS_OBJECT (v2));
  gts_object_destroy (GTS_OBJECT (v3));
  gts_allow_floating_vertices = FALSE;

  gts_surface_write (surface, stdout);

  if (gts_delaunay_check (surface)) {
    fprintf (stderr, "WARNING: surface is not Delaunay\n");
    return 1;
  }

  return 0;
}
