History: IntermediateTutorial4Source

#include <CEGUI/CEGUI.h>
 #include <OgreCEGUIRenderer.h>
 
 #include "ExampleApplication.h"
 
 class SelectionRectangle : public ManualObject
 {
 public:
     SelectionRectangle(const String &name)
         : ManualObject(name)
     {
         setUseIdentityProjection(true);
         setUseIdentityView(true);
         setRenderQueueGroup(RENDER_QUEUE_OVERLAY);
         setQueryFlags(0);
     }
  
     /**
      * Sets the corners of the SelectionRectangle.  Every parameter should be in the
      * range [0, 1] representing a percentage of the screen the SelectionRectangle
      * should take up.
      */
     void setCorners(float left, float top, float right, float bottom)
     {
         left = left * 2 - 1;
         right = right * 2 - 1;
         top = 1 - top * 2;
         bottom = 1 - bottom * 2;
 
         clear();
         begin("", RenderOperation::OT_LINE_STRIP);
             position(left, top, -1);
             position(right, top, -1);
             position(right, bottom, -1);
             position(left, bottom, -1);
             position(left, top, -1);
         end();
 
         AxisAlignedBox box;
         box.setInfinite();
         setBoundingBox(box);
     }
 
     void setCorners(const Vector2 &topLeft, const Vector2 &bottomRight)
     {
         setCorners(topLeft.x, topLeft.y, bottomRight.x, bottomRight.y);
     }
 };
 
 class DemoListener : public ExampleFrameListener, public OIS::MouseListener
 {
 public:
     DemoListener(RenderWindow* win, Camera* cam, SceneManager *sceneManager)
         : ExampleFrameListener(win, cam, false, true), mSceneMgr(sceneManager), mSelecting(false)
     {
         mMouse->setEventCallback(this);
  
         mRect = new SelectionRectangle("Selection SelectionRectangle");
         mSceneMgr->getRootSceneNode()->createChildSceneNode()->attachObject(mRect);
  
         mVolQuery = mSceneMgr->createPlaneBoundedVolumeQuery(PlaneBoundedVolumeList());
         mSelecting = false;
     } // DemoListener
  
     ~DemoListener()
     {
         mSceneMgr->destroyQuery(mVolQuery);
         delete mRect;
     }
  
     /* MouseListener callbacks. */
     bool mouseMoved(const OIS::MouseEvent &arg)
     {
         CEGUI::System::getSingleton().injectMouseMove(arg.state.X.rel, arg.state.Y.rel);
 
         if (mSelecting)
         {
             CEGUI::MouseCursor *mouse = CEGUI::MouseCursor::getSingletonPtr();
             mStop.x = mouse->getPosition().d_x / (float)arg.state.width;
             mStop.y = mouse->getPosition().d_y / (float)arg.state.height;
 
             mRect->setCorners(mStart, mStop);
         }
 
         return true;
     }
  
     bool mousePressed(const OIS::MouseEvent &arg, OIS::MouseButtonID id)
     {
         if (id == OIS::MB_Left)
         {
             CEGUI::MouseCursor *mouse = CEGUI::MouseCursor::getSingletonPtr();
             mStart.x = mouse->getPosition().d_x / (float)arg.state.width;
             mStart.y = mouse->getPosition().d_y / (float)arg.state.height;
             mStop = mStart;
  
             mSelecting = true;
             mRect->clear();
             mRect->setVisible(true);
         }
  
         return true;
     }
  
     bool mouseReleased(const OIS::MouseEvent &arg, OIS::MouseButtonID id)
     {
         if (id == OIS::MB_Left)
         {
             performSelection(mStart, mStop);
             mSelecting = false;
             mRect->setVisible(false);
         }
  
         return true;
     }
  
     void performSelection(const Vector2 &first, const Vector2 &second)
     {
         float left = first.x, right = second.x,
             top = first.y, bottom = second.y;
  
         if (left > right)
             swap(left, right);
  
         if (top > bottom)
             swap(top, bottom);
  
         if ((right - left) * (bottom - top) < 0.0001)
             return;
  
         // Convert screen positions into rays
         Ray topLeft = mCamera->getCameraToViewportRay(left, top);
         Ray topRight = mCamera->getCameraToViewportRay(right, top);
         Ray bottomLeft = mCamera->getCameraToViewportRay(left, bottom);
         Ray bottomRight = mCamera->getCameraToViewportRay(right, bottom);
  
         // The plane faces the counter clockwise position.
         PlaneBoundedVolume vol;
         vol.planes.push_back(Plane(topLeft.getPoint(3), topRight.getPoint(3), bottomRight.getPoint(3)));          // front plane
         vol.planes.push_back(Plane(topLeft.getOrigin(), topLeft.getPoint(100), topRight.getPoint(100)));          // top plane
         vol.planes.push_back(Plane(topLeft.getOrigin(), bottomLeft.getPoint(100), topLeft.getPoint(100)));        // left plane
         vol.planes.push_back(Plane(bottomLeft.getOrigin(), bottomRight.getPoint(100), bottomLeft.getPoint(100))); // bottom plane
         vol.planes.push_back(Plane(topRight.getOrigin(), topRight.getPoint(100), bottomRight.getPoint(100)));     // right plane
  
         PlaneBoundedVolumeList volList;
         volList.push_back(vol);
  
         mVolQuery->setVolumes(volList);
         SceneQueryResult result = mVolQuery->execute();
  
         deselectObjects();
         SceneQueryResultMovableList::iterator itr;
         for (itr = result.movables.begin(); itr != result.movables.end(); ++itr)
             selectObject(*itr);
     }
  
     void deselectObjects()
     {
         std::list<MovableObject*>::iterator itr;
         for (itr = mSelected.begin(); itr != mSelected.end(); ++itr)
             (*itr)->getParentSceneNode()->showBoundingBox(false);
     }
  
     void selectObject(MovableObject *obj)
     {
         obj->getParentSceneNode()->showBoundingBox(true);
         mSelected.push_back(obj);
     }
  
 private:
     Vector2 mStart, mStop;
     SceneManager *mSceneMgr;
     PlaneBoundedVolumeListSceneQuery *mVolQuery;
     std::list<MovableObject*> mSelected;
     SelectionRectangle *mRect;
     bool mSelecting;
 
 
     static void swap(float &x, float &y)
     {
         float tmp = x;
         x = y;
         y = tmp;
     }
 };
  
  class DemoApplication : public ExampleApplication
  {
  public:
     DemoApplication()
         : mRenderer(0), mSystem(0)
     {
     }
  
     ~DemoApplication() 
     {
         if (mSystem)
             delete mSystem;
  
         if (mRenderer)
             delete mRenderer;
     }
  
  protected:
      CEGUI::OgreCEGUIRenderer *mRenderer;
      CEGUI::System *mSystem;
  
      void createScene(void)
      {
          mRenderer = new CEGUI::OgreCEGUIRenderer(mWindow, Ogre::RENDER_QUEUE_OVERLAY, false, 3000, mSceneMgr);
          mSystem = new CEGUI::System(mRenderer);
  
          CEGUI::SchemeManager::getSingleton().loadScheme((CEGUI::utf8*)"TaharezLookSkin.scheme");
          CEGUI::MouseCursor::getSingleton().setImage((CEGUI::utf8*)"TaharezLook", (CEGUI::utf8*)"MouseArrow");
 
          mCamera->setPosition(-60, 100, -60);
          mCamera->lookAt(60, 0, 60);
  
          mSceneMgr->setAmbientLight(ColourValue::White);
          for (int i = 0; i < 10; ++i)
             for (int j = 0; j < 10; ++j)
             {
                 Entity *ent = mSceneMgr->createEntity("Robot" + StringConverter::toString(i + j * 10), "robot.mesh");
                 SceneNode *node = mSceneMgr->getRootSceneNode()->createChildSceneNode(Vector3(i * 15, 0, j * 15));
                 node->attachObject(ent);
                 node->setScale(0.1, 0.1, 0.1);
             }
      }
  
      void createFrameListener(void)
      {
         mFrameListener = new DemoListener(mWindow, mCamera, mSceneMgr);
         mFrameListener->showDebugOverlay(true);
         mRoot->addFrameListener(mFrameListener);
      }
  };
  
  #if OGRE_PLATFORM == OGRE_PLATFORM_WIN32
  #define WIN32_LEAN_AND_MEAN
  #include "windows.h"
  
  INT WINAPI WinMain(HINSTANCE hInst, HINSTANCE, LPSTR strCmdLine, INT)
  #else
  int main(int argc, char **argv)
  #endif
  {
      // Create application object
      DemoApplication app;
  
      try {
          app.go();
      } catch(Exception& e) {
  #if OGRE_PLATFORM == OGRE_PLATFORM_WIN32
          MessageBoxA(NULL, e.getFullDescription().c_str(), "An exception has occurred!",
              MB_OK | MB_ICONERROR | MB_TASKMODAL);
  #else
          fprintf(stderr, "An exception has occurred: %s\n",
              e.getFullDescription().c_str());
  #endif
      }
  
  
      return 0;
  }