/************************************************************************
**
** FILE  : hakaclip.c
**
** ZWECK : 
**
** AUTOR : Michael C. Ancutici
**	   Universitaet Stuttgart, Fakultaet Informatik
**
** DATUM : 14.03.93
**									
*************************************************************************/
#include	"hakaclip.h"
#include	"misc.h"
#include	"netsize.h"
#include 	"haka.H"
#include	<math.h>
#include	"ste.h"
#include	"tra.h"
#include	"celltype.h"


#define ABSTAND		5


/*************************************************************************
** FUNKTION:	HaKaClip
** ZWECK:	
** EINGABE:	
** AUSGABE:
** RETURN: 	
** ANMERK: 	
*************************************************************************/
void HaKaClip( Typ, Nr, x, y, erg)
  char 		Typ;
  int		Nr;
  int		x, y;
  KOORDINATE	*erg;
{
  int	 mx, my;
  int	 dx, dy;
  double rx, ry;
  int	 r;
  
  if (Typ == CE_STELLE) {
    mx = SteStelle[ Nr]->PosStelle.x;	/* Mittelpunkt absolut 		*/
    my = SteStelle[ Nr]->PosStelle.y;
    r = HA_STE_RAD + ABSTAND;		/* Radius			*/

    if (my != y) {    
      dx = x-mx;			/* Zielpunkt relativ 		*/
      dy = y-my;
    
      ry = r*dy/sqrt(dx*dx+dy*dy);
      if (dx<0) 
        ry = -ry;
      rx = ry*dx/dy;
    
      erg->x = (dx<0) ? mx - (int)rx : mx + (int)rx;
      erg->y = (dx<0) ? my - (int)ry : my + (int)ry;
    }
    else {		
      erg->x = (x>mx) ? mx + r : mx - r;
      erg->y = y;
    }
  }  
  else {
    mx = TraTrans[ Nr]->PosTrans.x;
    my = TraTrans[ Nr]->PosTrans.y;
    switch (TraTrans[ Nr]->Darstellung) {
      case TRA_QUAD:
        r = HA_TRA_DIA + ABSTAND;
        if (x-mx-my+y > 0) 	/* Dia 1 Uhr : rechts unten 	*/
          if (x-mx-y+my > 0) { 	/* Dia 5 Uhr : rechts oben 	*/
            /**** RECHTE SEITE **********************************/
            erg->x = mx+r;
            erg->y = my-(int)(r*(my-y)/(x-mx));
          }  
          else {
            /**** UNTERE SEITE **********************************/
            erg->x = mx+ (int)(r*(x-mx)/(y-my));
            erg->y = my+r;
          }  
        else      
          if (x-mx-y+my > 0) {	/* Dia 5 Uhr : rechts oben 	*/
            /**** OBERE SEITE ***********************************/
            erg->x = mx - (int)(r*(x-mx)/(y-my));
            erg->y = my-r;
          }  
          else {
            /**** LINKE SEITE ***********************************/
            erg->x = mx-r;
            erg->y = my+(int)(r*(my-y)/(x-mx));
          }  
      break;

      default:
        r = HA_STE_RAD;		/* Radius			*/

        if (my != y) {    
          dx = x-mx;			/* Zielpunkt relativ 		*/
          dy = y-my;
    
          ry = r*dy/sqrt(dx*dx+dy*dy);
          if (dx<0) 
            ry = -ry;
          rx = ry*dx/dy;
    
          erg->x = (dx<0) ? mx - (int)rx : mx + (int)rx;
          erg->y = (dx<0) ? my - (int)ry : my + (int)ry;
        }
        else {		
          erg->x = (x>mx) ? mx + r : mx - r;
          erg->y = y;
        }
      break;
    }
  }
}