src/gromacs/coordinateio/outputadapters/setstarttime.h

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  35 /*! \file
  36  * \brief
  37  * Declares gmx::SetStartTime
  38  *
  39  * \author Paul Bauer <paul.bauer.q@gmail.com>
  40  * \inpublicapi
  41  * \ingroup module_coordinateio
  42  */
  43 #ifndef GMX_FILEIO_SETSTARTTIME_H
  44 #define GMX_FILEIO_SETSTARTTIME_H
  45
  46 #include "gromacs/coordinateio/ioutputadapter.h"
  47 #include "gromacs/utility/real.h"
  48
  49 namespace gmx
  50 {
  51
  52 /*!\brief
  53  * SetStartTime class allows changing trajectory time information.
  54  *
  55  * This class allows the user to set custom start time information for the
  56  * current frame in a trajectory.
  57  *
  58  * \inpublicapi
  59  * \ingroup module_coordinateio
  60  *
  61  */
  62 class SetStartTime : public IOutputAdapter
  63 {
  64 public:
  65     /*! \brief
  66      * Construct object with choice for how to change initial time.
  67      *
  68      * \param[in] startTime User defined value for the initial time.
  69      */
  70     explicit SetStartTime(real startTime) :
  71         startTime_(startTime),
  72         haveProcessedFirstFrame_(false),
  73         differenceToInitialTime_(0)
  74     {
  75     }
  76     /*! \brief
  77      *  Move constructor for SetStartTime.
  78      */
  79     SetStartTime(SetStartTime&& old) noexcept = default;
  80
  81     ~SetStartTime() override {}
  82
  83     void processFrame(int /* framenumber */, t_trxframe* input) override;
  84
  85     void checkAbilityDependencies(unsigned long /* abilities */) const override {}
  86
  87 private:
  88     /*! \brief
  89      * Set initial time from first processed frame.
  90      *
  91      * Calculates the time shift between the user set time and the time
  92      * in the coordinate frame being processed from the first processed coordinate
  93      * frame. This time shift is then used to calculate new frame times for each processed
  94      * coordinate frame.
  95      *
  96      * \param[in] initialTime Time value obtained from first frame.
  97      */
  98     void setInitialTime(real initialTime);
  99
 100     /*! \brief
 101      * Stores the value of the initial time.
 102      *
 103      * In case users supply a new time step, the initial time of the
 104      * processed coordinate frame is stored here. In case the user also supplies
 105      * a new initial time, this variable is set to the user input instead.
 106      */
 107     real startTime_;
 108     //! Has the first frame been processed?
 109     bool haveProcessedFirstFrame_;
 110     /*! \brief
 111      * If the initial time is changed, we need to keep track of the initial
 112      * time difference to adjust the time of all following frames.
 113      */
 114     real differenceToInitialTime_;
 115 };
 116
 117 //! Smart pointer to manage the object.
 118 using SetStartTimePointer = std::unique_ptr<SetStartTime>;
 119
 120 } // namespace gmx
 121
 122 #endif