New Scene class definition. Also fixed a compile error for some users involving the definition of IID_IXAudio2

Client/Scene/Scene.hpp

@@ -0,0 +1,58 @@
+/*
+    Niotso - Copyright (C) 2012 Fatbag <X-Fi6@phppoll.org>
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+class Scene {
+    const float TickPeriod;
+    float TimeDelta;
+    virtual int Run(float TimeDelta) = 0;
+
+  protected:
+    Scene(float c) : TickPeriod(c), TimeDelta(0) {}
+
+  public:
+    int RunFor(float TimeDelta) {
+        if(TickPeriod == 0){
+            return Run(TimeDelta);
+        }
+        
+        bool Redraw = false;
+        this->TimeDelta += TimeDelta;
+        while(this->TimeDelta >= 0){
+            int result = Run(TickPeriod);
+            if(result == System::SHUTDOWN)
+                return System::SHUTDOWN;
+            if(result > 0) Redraw = true;
+            this->TimeDelta -= TickPeriod;
+        }
+        return (Redraw) ? 1 : -1;
+    }
+    
+    virtual void Render() = 0;
+};
+
+class LoginScreen : public Scene {
+  public: LoginScreen() : Scene(1.0f/15) {}
+
+  private:
+    int Run(float){
+        return 0;
+    }
+
+  public:
+    void Render(){
+    }
+};