#ifndef MASK_H
#define MASK_H
/*******************************************************************************
* E.S.O. - VLT project
*
* "@(#) $Id: AP_mask.h,v 2.43 2004/06/17 23:04:26 vltsccm Exp $"
*
* who       when      what
* --------  --------  ----------------------------------------------
* hummel  13/03/98  created
*/

/************************************************************************
 *
 *----------------------------------------------------------------------
 */

#ifndef __cplusplus
#error This is a C++ include file and cannot be used from plain C
#endif

#include "AP_pixel.h"

//----------------
class AP_mask : public AP_pixel {
//----------------

private: 
                 float wx[5],wy[5];    // current window position 4 points 1..4
                                       // wx/y[0]=center
                 float xma,yma,xmi,ymi,dist_pix_y,width_pix;
                 float pa; // position angle, the current rot_ang
                 float ax[21],ay[21],bx[21],by[21];
                                       // 19 slitlets 
                 int i_big,i_sma;      // index for X-orientation
public:
           static float  dist; // distance between two MOS slitlets in arcsec
           static float width;      // half width of a MOS slitlet in arcsec

void reset_mask(float px, float py, float PA);
     // creates a mask at px,py with rot, 
     // rot is anti-clock 

void rot_mask(float rot_ang);
     // rotate the possibly already rotated mask  once more be an amount of 
     // rot_ang degrees at the current position

void shift_mask(float dx, float dy);
     // shift the mask by (dx dy) 
   
     
void p2m(float *x, float *y);
     // coordinate transformation
     // CCD frame pixel to mask
     // input and output units are CCD pixel 

void m2p(float *x, float *y);
     // coordinate transformation
     // mask coords to CCD frame coords  
     // input and output units are CCD pixel 

void shift_mask_to(float px, float py);

int p_in_window(float px, float py);
     //  wrapper for p_in_area

float pr_on_slitlet(float px, float py, int slit);
     //  wrapper for pr_on_line

void print_mask();
     // no comment  

void test();
     // the functions above 

// the constructors
AP_mask(float scale,float focscale,float ra_min,
        float ra_max,float dec_min,float dec_max);
AP_mask(float scale,float focscale,float ra_min,
        float ra_max,float dec_min);
AP_mask(float scale,float focscale,float ra_min,
        float ra_max,float dec_min,int x_flag);
AP_mask();

};


#endif /*!_H*/