src/app/Application.cpp

   1 /*
   2  * Application.cpp
   3  *
   4  *  Created on: Apr 8, 2012
   5  *      Author: holy
   6  */
   7
   8 #include "Application.h"
   9
  10 #include "State.h"
  11
  12 #include <cassert>
  13
  14 namespace app {
  15
  16 Application::Application(sdl::InitScreen *screen, State *initialState)
  17 : screen(screen)
  18 , states()
  19 , timer()
  20 , last(SDL_GetTicks()) {
  21         assert(screen && "cannot create application without screen");
  22         assert(initialState && "cannot create application without initial state");
  23         RealPushState(initialState);
  24 }
  25
  26 Application::~Application(void) {
  27         PopAllStates();
  28 }
  29
  30
  31 State *Application::CurrentState(void) {
  32         return states.top();
  33 }
  34
  35 void Application::ChangeState(State *s) {
  36         RealPopState();
  37         RealPushState(s);
  38 }
  39
  40 void Application::PushState(State *s) {
  41         RealPushState(s);
  42 }
  43
  44 void Application::RealPushState(State *s) {
  45         states.push(s);
  46         s->EnterState(this, screen->Screen());
  47 }
  48
  49 void Application::PopState(void) {
  50         RealPopState();
  51 }
  52
  53 void Application::RealPopState(void) {
  54         if (states.empty()) return;
  55         states.top()->ExitState();
  56         delete states.top();
  57         states.pop();
  58 }
  59
  60 void Application::Quit(void) {
  61         PopAllStates();
  62 }
  63
  64 void Application::PopAllStates(void) {
  65         while (!states.empty()) {
  66                 RealPopState();
  67         }
  68 }
  69
  70
  71 void Application::Run(void) {
  72         while (CurrentState()) {
  73                 Loop();
  74         }
  75 }
  76
  77 void Application::Loop(void) {
  78         Uint32 now(SDL_GetTicks());
  79         Uint32 deltaT(now - last);
  80         if (deltaT > 34) deltaT = 34;
  81
  82         HandleEvents();
  83         UpdateWorld(deltaT);
  84         Render();
  85
  86         last = now;
  87 }
  88
  89
  90 void Application::HandleEvents(void) {
  91         if (!CurrentState()) return;
  92         SDL_Event event;
  93         while (SDL_PollEvent(&event)) {
  94                 switch (event.type) {
  95                         case SDL_QUIT:
  96                                 PopAllStates();
  97                                 break;
  98                         default:
  99                                 CurrentState()->HandleEvent(event);
 100                                 break;
 101                 }
 102         }
 103 }
 104
 105 void Application::UpdateWorld(Uint32 deltaT) {
 106         if (!CurrentState()) return;
 107         for (Uint32 i(0); i < deltaT; ++i) {
 108                 timer.Update(0.001);
 109                 CurrentState()->UpdateWorld(timer);
 110         }
 111 }
 112
 113 void Application::Render(void) {
 114         if (!CurrentState()) return;
 115         CurrentState()->Render(screen->Screen());
 116         screen->Flip();
 117 }
 118
 119 }