Dogcows Code - chaz/yoink/blob - src/moof/application.cc

   1
   2 /*]  Copyright (c) 2009-2010, Charles McGarvey  [**************************
   3 **]  All rights reserved.
   4 *
   5 * vi:ts=4 sw=4 tw=75
   6 *
   7 * Distributable under the terms and conditions of the 2-clause BSD license;
   8 * see the file COPYING for a complete text of the license.
   9 *
  10 **************************************************************************/
  11
  12 #include <cstdlib>                                      // exit, srand
  13 #include <boost/noncopyable.hpp>
  14
  15 #include <SDL/SDL.h>
  16 #include "fastevents.h"
  17
  18 #include "application.hh"
  19 #include "log.hh"
  20 #include "settings.hh"
  21 #include "timer.hh"
  22 #include "video.hh"
  23
  24
  25 namespace moof {
  26
  27
  28 application::application(settings& settings) :
  29         next_update_(timer::ticks()),
  30         total_time_(SCALAR(0.0))
  31 {
  32         unsigned random_seed;
  33         if (settings.get("rngseed", random_seed)) srand(random_seed);
  34         else srand(time(0));
  35
  36         scalar timestep = SCALAR(80.0);
  37         settings.get("timestep", timestep);
  38         timestep_ = SCALAR(1.0) / timestep;
  39         inverse_timestep_ = timestep;
  40
  41         scalar framerate = SCALAR(40.0);
  42         settings.get("framerate", framerate);
  43         framerate = SCALAR(1.0) / framerate;
  44
  45         update_timer_.init(boost::bind(&application::dispatch_update, this, _1, _2),
  46                                            timestep_, timer::repeat, this);
  47         draw_timer_.init(boost::bind(&application::dispatch_draw, this, _1, _2),
  48                                          framerate, timer::repeat, this);
  49 }
  50
  51
  52 void application::dispatch_update(timer& timer, scalar t)
  53 {
  54         event event;
  55
  56         while (FE_PollEvent(&event) == 1)
  57         {
  58                 switch (event.type)
  59                 {
  60                         case SDL_KEYDOWN:
  61
  62                                 if (event.key.keysym.sym == SDLK_ESCAPE &&
  63                                                 (SDL_GetModState() & KMOD_CTRL) )
  64                                 {
  65                                         // emergency escape
  66                                         log_warning("escape forced");
  67                                         exit(1);
  68                                 }
  69                                 break;
  70
  71                         case SDL_VIDEORESIZE:
  72
  73                                 video::current()->resize(event.resize.w, event.resize.h);
  74                                 break;
  75                 }
  76
  77                 handle_event(event);
  78         }
  79
  80
  81         const int MAX_FRAMESKIP = 15;
  82
  83         int i = 0;
  84         while (next_update_ < t && ++i < MAX_FRAMESKIP)
  85         {
  86                 total_time_ += timestep_;
  87                 update(total_time_, timestep_);
  88
  89                 next_update_ += timestep_;
  90         }
  91 }
  92
  93 void application::dispatch_draw(timer& timer, scalar t)
  94 {
  95         scalar alpha = (t + timestep_ - next_update_) * inverse_timestep_;
  96         if (alpha < SCALAR(0.0)) log_error("UH OH!!!!!  It's NEGATIVE", alpha);
  97         if (alpha > SCALAR(1.0)) log_error("UH OH!!!!!  It's POSITIVE", alpha);
  98
  99         draw(alpha);
 100         video::current()->swap();
 101 }
 102
 103
 104 } // namespace moof
 105