src/objects/venus.c

   1 /*
   2  * Copyright (C) 2008 Liam Girdwood
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation; either version 2 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 59 Temple Place, Suite 330,
  17  * Boston, MA 02111-1307, USA.
  18  */
  19
  20 #include <libnova/venus.h>
  21 #include "planet.h"
  22
  23 static void venus_update_cache(struct render_object *robject)
  24 {
  25         gdouble JD = robject->context.JD;
  26
  27         /* do we have to re-calc cache data */
  28         if (venus.cache.epoch_JD + venus.cache.diff_JD > JD ||
  29                 venus.cache.epoch_JD - venus.cache.diff_JD < JD) {
  30                 venus.cache.epoch_JD = JD;
  31
  32                 venus.cache.mag = venus.get_mag(venus.cache.epoch_JD);
  33                 venus.get_equ_posn(venus.cache.epoch_JD, &venus.cache.posn);
  34         }
  35         robject->coord[0].object_size =
  36                 robject->context.faintest_magnitude - venus.cache.mag;
  37         robject->coord[0].posn = &venus.cache.posn;
  38         robject->object = &venus;
  39 }
  40
  41 static void venus_render(struct render_object *robject, struct render_flags* rm)
  42 {
  43         if (robject->type == RT_FULL) {
  44
  45                 if (rm->show_label) {
  46                         gint label_offset = robject->coord[0].object_size + 15;
  47                         cairo_set_source_rgb(robject->cr, 0.9, 0.9, 0.1);
  48                         cairo_move_to (robject->cr,
  49                                         robject->coord[0].x - label_offset,
  50                                         robject->coord[0].y + label_offset);
  51                         cairo_show_text (robject->cr, venus.sobject.name);
  52                 }
  53
  54                 if (rm->show_axis_flag) {
  55
  56                 }
  57
  58                 cairo_set_source_rgb(robject->cr, 0.9, 0.9, 0.1);
  59                 cairo_arc (robject->cr,
  60                         robject->coord[0].x, robject->coord[0].y,
  61                         robject->coord[0].object_size, 0, 2 * M_PI);
  62                 if (!rm->show_outline) {
  63                         cairo_fill (robject->cr);
  64                 }
  65                 if (rm->show_phase) {
  66
  67                 }
  68
  69         } else {
  70                 cairo_set_source_rgb(robject->cr, 0.9, 0.9, 0.1);
  71                 cairo_arc (robject->cr,
  72                                 robject->coord[0].x, robject->coord[0].y,
  73                                 robject->coord[0].object_size, 0, 2 * M_PI);
  74                 cairo_fill (robject->cr);
  75         }
  76 }
  77
  78 struct planet venus = {
  79         .sobject.name = "Venus",
  80         .render         = venus_render,
  81         .update_cache   = venus_update_cache,
  82         .get_equ_posn   = ln_get_venus_equ_coords,
  83         .get_earth_dist = ln_get_venus_earth_dist,
  84         .get_solar_dist = ln_get_venus_solar_dist,
  85         .get_mag        = ln_get_venus_magnitude,
  86         .get_disk       = ln_get_venus_disk,
  87         .get_phase      = ln_get_venus_phase,
  88         .get_equ_sdiam  = ln_get_venus_sdiam,
  89         .get_pol_sdiam  = ln_get_venus_sdiam,
  90         .get_rst        = ln_get_venus_rst,
  91         .cache.epoch_JD = 0,
  92         .cache.diff_JD  = 0.1,
  93 };