source/Irrlicht/CSceneCollisionManager.cpp

   1 // Copyright (C) 2002-2012 Nikolaus Gebhardt\r
   2 // This file is part of the "Irrlicht Engine".\r
   3 // For conditions of distribution and use, see copyright notice in irrlicht.h\r
   4 \r
   5 #include "CSceneCollisionManager.h"\r
   6 #include "ICameraSceneNode.h"\r
   7 #include "SViewFrustum.h"\r
   8 \r
   9 #include "os.h"\r
  10 #include "irrMath.h"\r
  11 \r
  12 namespace irr\r
  13 {\r
  14 namespace scene\r
  15 {\r
  16 \r
  17 //! constructor\r
  18 CSceneCollisionManager::CSceneCollisionManager(ISceneManager* smanager, video::IVideoDriver* driver)\r
  19 : SceneManager(smanager), Driver(driver)\r
  20 {\r
  21         #ifdef _DEBUG\r
  22         setDebugName("CSceneCollisionManager");\r
  23         #endif\r
  24 \r
  25         if (Driver)\r
  26                 Driver->grab();\r
  27 }\r
  28 \r
  29 \r
  30 //! destructor\r
  31 CSceneCollisionManager::~CSceneCollisionManager()\r
  32 {\r
  33         if (Driver)\r
  34                 Driver->drop();\r
  35 }\r
  36 \r
  37 \r
  38 //! Returns a 3d ray which would go through the 2d screen coordinates.\r
  39 core::line3d<f32> CSceneCollisionManager::getRayFromScreenCoordinates(\r
  40         const core::position2d<s32> & pos, const ICameraSceneNode* camera)\r
  41 {\r
  42         core::line3d<f32> ln(0,0,0,0,0,0);\r
  43 \r
  44         if (!SceneManager)\r
  45                 return ln;\r
  46 \r
  47         if (!camera)\r
  48                 camera = SceneManager->getActiveCamera();\r
  49 \r
  50         if (!camera)\r
  51                 return ln;\r
  52 \r
  53         const scene::SViewFrustum* f = camera->getViewFrustum();\r
  54 \r
  55         core::vector3df farLeftUp = f->getFarLeftUp();\r
  56         core::vector3df lefttoright = f->getFarRightUp() - farLeftUp;\r
  57         core::vector3df uptodown = f->getFarLeftDown() - farLeftUp;\r
  58 \r
  59         const core::rect<s32>& viewPort = Driver->getViewPort();\r
  60         core::dimension2d<u32> screenSize(viewPort.getWidth(), viewPort.getHeight());\r
  61 \r
  62         f32 dx = pos.X / (f32)screenSize.Width;\r
  63         f32 dy = pos.Y / (f32)screenSize.Height;\r
  64 \r
  65         if (camera->isOrthogonal())\r
  66                 ln.start = f->cameraPosition + (lefttoright * (dx-0.5f)) + (uptodown * (dy-0.5f));\r
  67         else\r
  68                 ln.start = f->cameraPosition;\r
  69 \r
  70         ln.end = farLeftUp + (lefttoright * dx) + (uptodown * dy);\r
  71 \r
  72         return ln;\r
  73 }\r
  74 \r
  75 } // end namespace scene\r
  76 } // end namespace irr\r