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 , last(SDL_GetTicks())
  20 , toPop(0) {
  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() {
  27         PopAllStates();
  28 }
  29
  30
  31 State *Application::CurrentState() {
  32         return states.top();
  33 }
  34
  35 void Application::UpdateState() {
  36         while (toPop > 0) {
  37                 RealPopState();
  38                 --toPop;
  39         }
  40         while (!toPush.empty()) {
  41                 State *s(toPush.front());
  42                 toPush.pop();
  43                 RealPushState(s);
  44         }
  45 }
  46
  47 void Application::ChangeState(State *s) {
  48         PopState();
  49         PushState(s);
  50 }
  51
  52 void Application::PushState(State *s) {
  53         toPush.push(s);
  54 }
  55
  56 void Application::RealPushState(State *s) {
  57         states.push(s);
  58         s->EnterState(*this, screen->Screen());
  59 }
  60
  61 void Application::PopState() {
  62         ++toPop;
  63 }
  64
  65 void Application::RealPopState() {
  66         if (states.empty()) return;
  67         states.top()->ExitState();
  68         delete states.top();
  69         states.pop();
  70 }
  71
  72 void Application::Quit() {
  73         PopAllStates();
  74 }
  75
  76 void Application::PopAllStates() {
  77         while (!states.empty()) {
  78                 RealPopState();
  79         }
  80 }
  81
  82
  83 void Application::Run() {
  84         while (CurrentState()) {
  85                 Loop();
  86         }
  87 }
  88
  89 void Application::Loop() {
  90         Uint32 now(SDL_GetTicks());
  91         Uint32 deltaT(now - last);
  92         if (deltaT > 34) deltaT = 34;
  93
  94         HandleEvents();
  95         UpdateWorld(deltaT);
  96         Render();
  97
  98         last = now;
  99         UpdateState();
 100 }
 101
 102
 103 void Application::HandleEvents() {
 104         if (!CurrentState()) return;
 105         input.ResetInteractiveState();
 106         SDL_Event event;
 107         while (SDL_PollEvent(&event)) {
 108                 switch (event.type) {
 109                         case SDL_QUIT:
 110                                 PopAllStates();
 111                                 break;
 112                         case SDL_VIDEORESIZE:
 113                                 screen->Resize(event.resize.w, event.resize.h);
 114                                 CurrentState()->Resize(event.resize.w, event.resize.h);
 115                                 break;
 116                         case SDL_KEYDOWN:
 117                         case SDL_KEYUP:
 118                                 input.HandleKeyboardEvent(event.key);
 119                                 break;
 120                         default:
 121                                 // skip event
 122                                 break;
 123                 }
 124         }
 125         CurrentState()->HandleInput(input);
 126 }
 127
 128 void Application::UpdateWorld(Uint32 deltaT) {
 129         if (!CurrentState()) return;
 130         for (Uint32 i(0); i < deltaT; ++i) {
 131                 CurrentState()->UpdateWorld(0.001f);
 132         }
 133 }
 134
 135 void Application::Render(void) {
 136         if (!CurrentState()) return;
 137         CurrentState()->Render(screen->Screen());
 138         screen->Flip();
 139 }
 140
 141 }