sys/src/cmd/astro/init.c

   1 #include "astro.h"
   2
   3 Obj2*   objlst[] =
   4 {
   5         &osun,
   6         &omoon,
   7         &oshad,
   8         &omerc,
   9         &ovenus,
  10         &omars,
  11         &ojup,
  12         &osat,
  13         &ouran,
  14         &onept,
  15         &oplut,
  16         &ocomet,
  17         0,
  18 };
  19
  20 struct  idata
  21 {
  22         char*   name;
  23         char*   name1;
  24         void    (*obj)(void);
  25 } idata[] =
  26 {
  27         "The sun",      "sun",          fsun,
  28         "The moon",     "moon",         moon,
  29         "The shadow",   "shadow",       shad,
  30         "Mercury",      "mercury",      merc,
  31         "Venus",        "venus",        venus,
  32         "Mars",         "mars",         mars,
  33         "Jupiter",      "jupiter",      jup,
  34         "Saturn",       "saturn",       sat,
  35         "Uranus",       "uranus",       uran,
  36         "Neptune",      "neptune",      nept,
  37         "Pluto",        "pluto",        plut,
  38         "Comet",        "comet",        comet,
  39 };
  40
  41 void
  42 init(void)
  43 {
  44         Obj2 *q;
  45         int i;
  46
  47         glat = nlat - (692.74*radsec)*sin(2.*nlat)
  48                  + (1.16*radsec)*sin(4.*nlat);
  49         erad = .99832707e0 + .00167644e0*cos(2.*nlat)
  50                  - 0.352e-5*cos(4.*nlat)
  51                  + 0.001e-5*cos(6.*nlat)
  52                  + 0.1568e-6*elev;
  53
  54         for(i=0; q=objlst[i]; i++) {
  55                 q->name = idata[i].name;
  56                 q->name1 = idata[i].name1;
  57                 q->obj = idata[i].obj;
  58         }
  59         ostar.obj = fstar;
  60         ostar.name = "star";
  61 }
  62
  63 void
  64 setime(double d)
  65 {
  66         double x, xm, ym, zm;
  67
  68         eday = d + deltat/86400.;
  69         wlong = awlong + 15.*deltat*radsec;
  70
  71         capt = eday/36524.220e0;
  72         capt2 = capt*capt;
  73         capt3 = capt*capt2;
  74         nutate();
  75         eday += .1;
  76         sun();
  77         srad = rad;
  78         xm = rad*cos(beta)*cos(lambda);
  79         ym = rad*cos(beta)*sin(lambda);
  80         zm = rad*sin(beta);
  81         eday -= .1;
  82         sun();
  83         xms = rad*cos(beta)*cos(lambda);
  84         yms = rad*cos(beta)*sin(lambda);
  85         zms = rad*sin(beta);
  86         x = .057756;
  87         xdot = x*(xm-xms);
  88         ydot = x*(ym-yms);
  89         zdot = x*(zm-zms);
  90 }
  91
  92 void
  93 setobj(Obj1 *op)
  94 {
  95         Obj1 *p;
  96
  97         p = op;
  98         p->ra = ra;
  99         p->decl2 = decl2;
 100         p->semi2 = semi2;
 101         p->az = az;
 102         p->el = el;
 103         p->mag = mag;
 104 }
 105
 106 long    starsao = 0;
 107
 108 void
 109 fstar(void)
 110 {
 111
 112         ra = ostar.point[0].ra;
 113         decl2 = ostar.point[0].decl2;
 114         semi2 = ostar.point[0].semi2;
 115         az = ostar.point[0].az;
 116         el = ostar.point[0].el;
 117         mag = ostar.point[0].mag;
 118 }
 119
 120 void
 121 fsun(void)
 122 {
 123
 124         beta = 0;
 125         rad = 0;
 126         lambda = 0;
 127         motion = 0;
 128         helio();
 129         geo();
 130         seday = eday;
 131         salph = alpha;
 132         sdelt = delta;
 133         mag = lmb2;
 134 }
 135
 136 void
 137 shad(void)
 138 {
 139
 140         if(seday != eday)
 141                 fsun();
 142         if(meday != eday)
 143                 moon();
 144         alpha = fmod(salph+pi, pipi);
 145         delta = -sdelt;
 146         hp = mhp;
 147         semi = 1.0183*mhp/radsec - 969.85/srad;
 148         geo();
 149 }