data.h

struct datapoint
{time_t when;
 float tide;
 int  tidepos;
 bool dark;
};
 
const int DisplayWidth=800;
const int DisplayHt=460;
const int BottomBand=480-DisplayHt;
const double DisplayTop=7.0;
const double DisplayBot=-3.0;
const double delta=((double)DisplayHt)/(DisplayTop-DisplayBot);
 
inline int DataToPos(double v)
{
    double offset=v-DisplayBot;
    int rv=DisplayHt-(int)(delta*offset);
    if (rv<0) rv=0;
    if(rv>=DisplayHt) rv=DisplayHt-1;
    return rv;
}
extern volatile datapoint dataplot[DisplayWidth];
extern volatile int LeftEdge;
extern OS_CRIT CalcCrit;