src/mainloop.cpp

   1 //  $Id$
   2 //
   3 //  SuperTux
   4 //  Copyright (C) 2006 Matthias Braun <matze@braunis.de>
   5 //
   6 //  This program is free software; you can redistribute it and/or
   7 //  modify it under the terms of the GNU General Public License
   8 //  as published by the Free Software Foundation; either version 2
   9 //  of the License, or (at your option) any later version.
  10 //
  11 //  This program is distributed in the hope that it will be useful,
  12 //  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 //  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 //  GNU General Public License for more details.
  15 //
  16 //  You should have received a copy of the GNU General Public License
  17 //  along with this program; if not, write to the Free Software
  18 //  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  19 #include <config.h>
  20
  21 #include "mainloop.hpp"
  22
  23 #include <stdlib.h>
  24 #include <SDL.h>
  25 #include "video/drawing_context.hpp"
  26 #include "control/joystickkeyboardcontroller.hpp"
  27 #include "gui/menu.hpp"
  28 #include "audio/sound_manager.hpp"
  29 #include "scripting/time_scheduler.hpp"
  30 #include "scripting/squirrel_util.hpp"
  31 #include "gameconfig.hpp"
  32 #include "main.hpp"
  33 #include "resources.hpp"
  34 #include "screen.hpp"
  35 #include "screen_fade.hpp"
  36 #include "timer.hpp"
  37 #include "player_status.hpp"
  38 #include "video/renderer.hpp"
  39 #include "random_generator.hpp"
  40
  41 // the engine will be run with a logical framerate of 64fps.
  42 // We chose 64fps here because it is a power of 2, so 1/64 gives an "even"
  43 // binary fraction...
  44 static const float LOGICAL_FPS = 64.0;
  45 /** ticks (as returned from SDL_GetTicks) per frame */
  46 static const Uint32 TICKS_PER_FRAME = (Uint32) (1000.0 / LOGICAL_FPS);
  47 /** don't skip more than every 2nd frame */
  48 static const int MAX_FRAME_SKIP = 2;
  49
  50 float game_speed = 1.0f;
  51
  52 MainLoop* main_loop = NULL;
  53
  54 MainLoop::MainLoop()
  55   : speed(1.0), nextpop(false), nextpush(false), fps(0), screenshot_requested(false)
  56 {
  57   using namespace Scripting;
  58   TimeScheduler::instance = new TimeScheduler();
  59 }
  60
  61 MainLoop::~MainLoop()
  62 {
  63   using namespace Scripting;
  64   delete TimeScheduler::instance;
  65   TimeScheduler::instance = NULL;
  66
  67   for(std::vector<Screen*>::iterator i = screen_stack.begin();
  68       i != screen_stack.end(); ++i) {
  69     delete *i;
  70   }
  71 }
  72
  73 void
  74 MainLoop::push_screen(Screen* screen, ScreenFade* screen_fade)
  75 {
  76   this->next_screen.reset(screen);
  77   this->screen_fade.reset(screen_fade);
  78   nextpush = !nextpop;
  79   nextpop = false;
  80   speed = 1.0;
  81 }
  82
  83 void
  84 MainLoop::exit_screen(ScreenFade* screen_fade)
  85 {
  86   next_screen.reset(NULL);
  87   this->screen_fade.reset(screen_fade);
  88   nextpop = true;
  89   nextpush = false;
  90 }
  91
  92 void
  93 MainLoop::set_screen_fade(ScreenFade* screen_fade)
  94 {
  95   this->screen_fade.reset(screen_fade);
  96 }
  97
  98 void
  99 MainLoop::quit(ScreenFade* screen_fade)
 100 {
 101   for(std::vector<Screen*>::iterator i = screen_stack.begin();
 102           i != screen_stack.end(); ++i)
 103     delete *i;
 104   screen_stack.clear();
 105
 106   exit_screen(screen_fade);
 107 }
 108
 109 void
 110 MainLoop::set_speed(float speed)
 111 {
 112   this->speed = speed;
 113 }
 114
 115 float
 116 MainLoop::get_speed() const
 117 {
 118   return speed;
 119 }
 120
 121 void
 122 MainLoop::draw_fps(DrawingContext& context, float fps_fps)
 123 {
 124   char str[60];
 125   snprintf(str, sizeof(str), "%3.1f", fps_fps);
 126   const char* fpstext = "FPS";
 127   context.draw_text(white_text, fpstext, Vector(SCREEN_WIDTH - white_text->get_text_width(fpstext) - gold_text->get_text_width(" 99999") - BORDER_X, BORDER_Y + 20), ALIGN_LEFT, LAYER_HUD);
 128   context.draw_text(gold_text, str, Vector(SCREEN_WIDTH - BORDER_X, BORDER_Y + 20), ALIGN_RIGHT, LAYER_HUD);
 129 }
 130
 131 void
 132 MainLoop::draw(DrawingContext& context)
 133 {
 134   static Uint32 fps_ticks = SDL_GetTicks();
 135   static int frame_count = 0;
 136
 137   current_screen->draw(context);
 138   if(Menu::current() != NULL)
 139     Menu::current()->draw(context);
 140   if(screen_fade.get() != NULL)
 141     screen_fade->draw(context);
 142   Console::instance->draw(context);
 143
 144   if(config->show_fps)
 145     draw_fps(context, fps);
 146
 147   // if a screenshot was requested, pass request on to drawing_context
 148   if (screenshot_requested) {
 149     context.take_screenshot();
 150     screenshot_requested = false;
 151   }
 152   context.do_drawing();
 153
 154   /* Calculate frames per second */
 155   if(config->show_fps)
 156   {
 157     ++frame_count;
 158
 159     if(SDL_GetTicks() - fps_ticks >= 500)
 160     {
 161       fps = (float) frame_count / .5;
 162       frame_count = 0;
 163       fps_ticks = SDL_GetTicks();
 164     }
 165   }
 166 }
 167
 168 void
 169 MainLoop::update_gamelogic(float elapsed_time)
 170 {
 171   Scripting::update_debugger();
 172   Scripting::TimeScheduler::instance->update(game_time);
 173   current_screen->update(elapsed_time);
 174   if(screen_fade.get() != NULL)
 175     screen_fade->update(elapsed_time);
 176   Console::instance->update(elapsed_time);
 177 }
 178
 179 void
 180 MainLoop::process_events()
 181 {
 182   main_controller->update();
 183   Uint8* keystate = SDL_GetKeyState(NULL);
 184   SDL_Event event;
 185   while(SDL_PollEvent(&event))
 186     {
 187       main_controller->process_event(event);
 188
 189       if(Menu::current() != NULL)
 190         Menu::current()->event(event);
 191
 192       switch(event.type)
 193         {
 194           case SDL_QUIT:
 195             quit();
 196             break;
 197
 198           case SDL_VIDEORESIZE:
 199             Renderer::instance()->resize(event.resize.w, event.resize.h);
 200             Menu::recalc_pos();
 201             break;
 202
 203           case SDL_KEYDOWN:
 204             if (event.key.keysym.sym == SDLK_F11)
 205               {
 206                 config->use_fullscreen = !config->use_fullscreen;
 207                 init_video();
 208               }
 209             else if (event.key.keysym.sym == SDLK_PRINT)
 210               {
 211                 take_screenshot();
 212               }
 213             else if (event.key.keysym.sym == SDLK_F1 &&
 214                      (keystate[SDLK_LCTRL] || keystate[SDLK_RCTRL]) &&
 215                      keystate[SDLK_c])
 216               {
 217                 Console::instance->toggle();
 218                 config->console_enabled = true;
 219                 config->save();
 220               }
 221             break;
 222         }
 223     }
 224 }
 225
 226 void
 227 MainLoop::handle_screen_switch()
 228 {
 229   while( (next_screen.get() != NULL || nextpop) &&
 230       (screen_fade.get() == NULL || screen_fade->done())) {
 231     if(current_screen.get() != NULL) {
 232       current_screen->leave();
 233     }
 234
 235     if(nextpop) {
 236       if(screen_stack.empty()) {
 237         running = false;
 238         break;
 239       }
 240       next_screen.reset(screen_stack.back());
 241       screen_stack.pop_back();
 242     }
 243     if(nextpush && current_screen.get() != NULL) {
 244       screen_stack.push_back(current_screen.release());
 245     }
 246
 247     nextpush = false;
 248     nextpop = false;
 249     speed = 1.0;
 250     if(next_screen.get() != NULL)
 251       next_screen->setup();
 252     current_screen.reset(next_screen.release());
 253     screen_fade.reset(NULL);
 254
 255     waiting_threads.wakeup();
 256   }
 257 }
 258
 259 void
 260 MainLoop::run(DrawingContext &context)
 261 {
 262   Uint32 last_ticks = 0;
 263   Uint32 elapsed_ticks = 0;
 264
 265   running = true;
 266   while(running) {
 267
 268     handle_screen_switch();
 269     if(!running || current_screen.get() == NULL)
 270       break;
 271
 272     Uint32 ticks = SDL_GetTicks();
 273     elapsed_ticks += ticks - last_ticks;
 274     last_ticks = ticks;
 275
 276     Uint32 ticks_per_frame = (Uint32) (TICKS_PER_FRAME * game_speed);
 277
 278     if (elapsed_ticks > ticks_per_frame*4) {
 279       // when the game loads up or levels are switched the
 280       // elapsed_ticks grows extremly large, so we just ignore those
 281       // large time jumps
 282       elapsed_ticks = 0;
 283     }
 284
 285     int frames = 0;
 286
 287     if (elapsed_ticks > ticks_per_frame)
 288       {
 289         while(elapsed_ticks > ticks_per_frame && frames < MAX_FRAME_SKIP)
 290           {
 291             elapsed_ticks -= ticks_per_frame;
 292             float timestep = 1.0 / LOGICAL_FPS;
 293             real_time += timestep;
 294             timestep *= speed;
 295             game_time += timestep;
 296
 297             process_events();
 298             update_gamelogic(timestep);
 299             frames += 1;
 300           }
 301
 302         draw(context);
 303       }
 304
 305     sound_manager->update();
 306
 307     SDL_Delay(0);
 308   }
 309 }
 310
 311 void
 312 MainLoop::take_screenshot()
 313 {
 314   screenshot_requested = true;
 315 }
 316