PixelChannelIdentifier.h

Go to the documentation of this file.

#ifndef DATAFORMATS_PIXELCHANMNELIDENTIFIER_H
#define DATAFORMATS_PIXELCHANMNELIDENTIFIER_H

#include <utility>
#include "FWCore/Utilities/interface/GCC11Compatibility.h"

class PixelChannelIdentifier {
public:
  typedef unsigned int PackedDigiType;
  typedef unsigned int ChannelType;

  static std::pair<int, int> channelToPixel(int ch) {
    int row = (ch >> thePacking.column_width) & thePacking.row_mask;
    int col = ch & thePacking.column_mask;
    return std::pair<int, int>(row, col);
  }

  static int pixelToChannel(int row, int col) { return (row << thePacking.column_width) | col; }

  class Packing {
  public:
    // Constructor: pre-computes masks and shifts from field widths
    // gcc4.8: sorry, unimplemented: use of the value of the object being constructed in a constant expression
    // no constexpr yet....
    Packing(unsigned int row_w, unsigned int column_w, unsigned int time_w, unsigned int adc_w)
        : row_width(row_w),
          column_width(column_w),
          adc_width(adc_w),
          row_shift(0),
          column_shift(row_shift + row_w),
          time_shift(column_shift + column_w),
          adc_shift(time_shift + time_w),
          row_mask(~(~0U << row_w)),
          column_mask(~(~0U << column_w)),
          time_mask(~(~0U << time_w)),
          adc_mask(~(~0U << adc_w)),
          rowcol_mask(~(~0U << (column_w + row_w))),
          max_row(row_mask),
          max_column(column_mask),
          max_adc(adc_mask) {}

    int row_width;
    int column_width;
    int adc_width;

    int row_shift;
    int column_shift;
    int time_shift;
    int adc_shift;

    PackedDigiType row_mask;
    PackedDigiType column_mask;
    PackedDigiType time_mask;
    PackedDigiType adc_mask;
    PackedDigiType rowcol_mask;

    int max_row;
    int max_column;
    int max_adc;
  };

public:
  //#ifndef CMS_NOCXX11
  static Packing packing() { return Packing(8, 9, 4, 11); }

  static const Packing thePacking;

  //#else
  //static constexpr Packing packing() { return Packing(8, 9, 4, 11);}

  //static constexpr Packing thePacking = packing();
  //#endif
};

#endif