/******************************************************************************
*         neutron ray-tracing package
*         Copyright (C) 1997-2007, All rights reserved
*         Risoe National Laboratory, Roskilde, Denmark
*         Institut Laue Langevin, Grenoble, France
*
* Component: CavitiesOut
*
* %I
* Written by: Henrich Frielinghaus
* Date: Oct 2007
* Origin: JCNS - FZ-Juelich
*
* Slit - sorting in channels
*
* %D
* This routine sorts the 'full' neutron beam (given by xw,yw)
* in xc,yc channels. These can be imagined as cavities.
* CavitiesOut sorts these channels back to normal coordinates. 
*
* Example: Slit(xw=0.05, yw=0.05, xc=4, yc=1)
*
* %P
* INPUT PARAMETERS
*
* xw: [m]  width in X-dir (full width, might be larger for trumpets)
* yw: [m]  width in Y-dir (full width, might be larger for trumpets)
* xc: [1]  Number of x-channels
* yc: [1]  Number of y-channels
*
*
* %E
*******************************************************************************/


DEFINE COMPONENT CavitiesOut

SETTING PARAMETERS (xw=0.05, yw=0.05, xc=1, yc=1)


DECLARE
%{
  int xcc;
  int ycc;
  int mcs_xc;
  int mcs_yc;
%}

INITIALIZE
%{
  xcc = floor (fabs (xc));
  ycc = floor (fabs (yc));
  if (xcc == 0)
    xcc = 1;
  if (ycc == 0)
    ycc = 1;
  mcs_xc = 0;
  mcs_yc = 0;
%}

TRACE
%{
  PROP_Z0;
  if (x < -0.5 * xw / xcc || x > 0.5 * xw / xcc || y < -0.5 * yw / ycc || y > 0.5 * yw / ycc)
    ABSORB;
  else {
    SCATTER;
    x = x + (mcs_xc + 0.5 - 0.5 * xcc) * xw / xcc;
    y = y + (mcs_yc + 0.5 - 0.5 * ycc) * yw / ycc;
  }
%}

MCDISPLAY
%{

  multiline (3, -(double)xw, 0.5 * yw, 0.0, -0.5 * xw, 0.5 * yw, 0.0, -0.5 * xw, (double)yw, 0.0);
  multiline (3, (double)xw, 0.5 * yw, 0.0, 0.5 * xw, 0.5 * yw, 0.0, 0.5 * xw, (double)yw, 0.0);
  multiline (3, -(double)xw, -0.5 * yw, 0.0, -0.5 * xw, -0.5 * yw, 0.0, -0.5 * xw, -(double)yw, 0.0);
  multiline (3, (double)xw, -0.5 * yw, 0.0, 0.5 * xw, -0.5 * yw, 0.0, 0.5 * xw, -(double)yw, 0.0);
%}

END