/* See {FunnyBall.h} */
#include <FunnyBall.h>

/* Last edited on 2007-02-04 16:19:20 by stolfi */

#define FunnyBall_C_COPYRIGHT \
  "Copyright © 2000,2007 Universidade Estadual de Campinas (UNICAMP)"

#include <Tools.h>
#include <Triangulation.h>
#include <Octf.h>
#include <OctfData.h>
#include <Polygon.h>

#include <r4.h>
#include <vec.h>

#include <assert.h>
#include <stdio.h>

Place_t GlueBall(Place_t a, Place_t b);
  /* Make the glueing of two simples 2-gon walls around of one common wall.
     The place {a} and its adjacent ones with the same wall component are
     killed. */

void SetFunnyBallInteriorCell(Place_t p, Cell_t n);
  /* Set to {n} the cell slots of the 8 places on the interior
    of the funny ball {n}. */

FourPlaces_t MakeFunnyBall(void)
  { FourPlaces_t co;
    int i;
    for (i = 0; i < 4; i++) { co.p[i] = PolygonMakeSng(2); }

    /* Glue Walls */
    for (i = 0; i < 4; i++)
      { SetNextF(co.p[i],Clock(NextE(co.p[(i+1) % 4]))); 
        SetEdgeInfo(co.p[i], PWedge(Clock(NextE(co.p[(i+1) % 4])))->edge);
        SetOrgAll(co.p[i], OrgV(co.p[i]));
        SetOrgAll(Clock(co.p[i]), OrgV(Clock(co.p[i]))); 
      }

    Cell_t q = MakeCell(0);
    SetFunnyBallInteriorCell(co.p[0], q);

    return co;
  }

Place_t GlueBall(Place_t a, Place_t b)
  { assert(SpinBit(a) == SpinBit(b));
    Meld(a,b);

    /* Update the edge slots */
    SetRingEdgeInfo(b, PEdge(b));
    SetRingEdgeInfo(NextE(b), PEdge(NextE(b)));
    
    /* Update the node slots */
    SetOrgAll(b, OrgV(b));
    SetOrgAll(NextE(b), OrgV(NextE(b)));
    
    /* Update the cell slots */
    SetPneg(b, PnegP(a));
    SetPneg(PrevE(b), PnegP(PrevE(a)));

    return b;
  }

void SetFunnyBallInteriorCell(Place_t p, Cell_t n)
  { SetPnegOfNearbyWalls(p, n);
    Place_t t = p;
    do { SetPnegOfNearbyWalls(Clock(PrevF(t)),n); t = PrevE(t); } while (t != p); 
    t = PrevF(PrevE(PrevF(p)));
    SetPnegOfNearbyWalls(t, n);
  }

#define FunnyBall_C_author \
  "Created by L. A. P. Lozada, 2000.\n" \
  "Modification history:\n" \
  "  26-01-2007 : Converted to C by J. Stolfi, extracted from {}."