text: //-----------------------------------------------------------------------------
  // Copyright (c) 2012 GarageGames, LLC
  //
  // Permission is hereby granted, free of charge, to any person obtaining a copy
  // of this software and associated documentation files (the "Software"), to
  // deal in the Software without restriction, including without limitation the
  // rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
  // sell copies of the Software, and to permit persons to whom the Software is
  // furnished to do so, subject to the following conditions:
  //
  // The above copyright notice and this permission notice shall be included in
  // all copies or substantial portions of the Software.
  //
  // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  // FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
  // IN THE SOFTWARE.
  //-----------------------------------------------------------------------------
     
  //-----------------------------------------------------------------------------
  // Volumetric Fog Rendertarget Manager
  //
  // Creates and maintains one set of rendertargets to be used by every
  // VolumetricFog object in the scene.
  //
  // Will be loaded at startup end removed when ending game.
  //
  //-----------------------------------------------------------------------------
     
  #include "VolumetricFogRTManager.h"
  #include "core/module.h"
  #include "scene/sceneManager.h"
  #include "windowManager/platformWindowMgr.h"
  #include "console/engineAPI.h"
  #include "gui/core/guiCanvas.h"
  #include "gfx/gfxDevice.h"
     
  MODULE_BEGIN(VolumetricFogRTManager)
     
  MODULE_INIT_AFTER(Scene)
  MODULE_SHUTDOWN_BEFORE(Scene)
     
  MODULE_INIT
  {
     gVolumetricFogRTManager = new VolumetricFogRTManager;
     gClientSceneGraph->addObjectToScene(gVolumetricFogRTManager);
  }
     
  MODULE_SHUTDOWN
  {
     gClientSceneGraph->removeObjectFromScene(gVolumetricFogRTManager);
     SAFE_DELETE(gVolumetricFogRTManager);
  }
     
  MODULE_END;
     
  ConsoleDocClass( VolumetricFogRTManager,
  "@brief Creates and maintains one set of rendertargets to be used by every\n"
  "VolumetricFog object in the scene.\n\n"
  "Will be loaded at startup end removed when ending game.\n\n"
  "Methods:\n"
  " get() returns the currently loaded VolumetricFogRTManager, also accessible\n"
  " through VFRTM define.\n"
  " Init() Initializes the rendertargets, called when a VolumetricFog object is\n"
  " added to the scene.\n"
  " isInitialed() returns true if Rendertargets are present, false if not, then\n"
  " Init() should be called to create the rendertargets.\n"
  " setQuality(U32 Quality) Normally a rendertarget has the same size as the view,\n"
  " with this method you can scale down the size of it.\n"
  " Be aware that scaling down will introduce renderartefacts.\n"
  "@ingroup Atmosphere"
  );
     
  VolumetricFogRTMResizeSignal VolumetricFogRTManager::smVolumetricFogRTMResizeSignal;
     
  VolumetricFogRTManager *gVolumetricFogRTManager = NULL;
  
  S32 VolumetricFogRTManager::mTargetScale = 1;
     
  IMPLEMENT_CONOBJECT(VolumetricFogRTManager);
     
  VolumetricFogRTManager::VolumetricFogRTManager()
  {
     setGlobalBounds();
     mTypeMask |= EnvironmentObjectType;
     mNetFlags.set(IsGhost);
     mPlatformWindow = NULL;
     mIsInitialized = false;
     mNumFogObjects = 0;
     mWidth = 0;
     mHeight = 0;
  }
     
  VolumetricFogRTManager::~VolumetricFogRTManager()
  {
     if (mFrontTarget.isRegistered())
        mFrontTarget.unregister();
     
     if (mDepthTarget.isRegistered())
        mDepthTarget.unregister();
     
     if (mDepthBuffer.isValid())
        mDepthBuffer->kill();
     
     if (mFrontBuffer.isValid())
        mFrontBuffer->kill();
  }
     
  void VolumetricFogRTManager::onSceneRemove()
  {
     if (mIsInitialized)
        mPlatformWindow->resizeEvent.remove(this, &VolumetricFogRTManager::ResizeRT);
  }
     
  void VolumetricFogRTManager::onRemove()
  {
     removeFromScene();
     Parent::onRemove();
  }
     
  void VolumetricFogRTManager::consoleInit()
  {
     Con::addVariable("$pref::VolumetricFog::Quality", TypeS32, &mTargetScale,
     "The scale of the rendertargets.\n"
     "@ingroup Rendering\n");
  }
     
  bool VolumetricFogRTManager::Init()
  {
     if (mIsInitialized)
     {
        Con::errorf("VolumetricFogRTManager allready initialized!!");
        return true;
     }
  
     if (GFX->getAdapterType() == NullDevice)
     {
        mIsInitialized = true;
        Con::errorf("VolumetricFogRTManager - Dedicated server");
        return true;
     }
  
     GuiCanvas* cv = dynamic_cast<GuiCanvas*>(Sim::findObject("Canvas"));
     if (cv == NULL)
     {
        Con::errorf("VolumetricFogRTManager::Init() - Canvas not found!!");
        return false;
     }
     
     mPlatformWindow = cv->getPlatformWindow();
     mPlatformWindow->resizeEvent.notify(this,&VolumetricFogRTManager::ResizeRT);
     
     if (mTargetScale < 1 || GFX->getAdapterType() == Direct3D11)
        mTargetScale = 1;
     
     mWidth = mFloor(mPlatformWindow->getClientExtent().x / mTargetScale);
     mHeight = mFloor(mPlatformWindow->getClientExtent().y / mTargetScale);
     
     mDepthBuffer = GFXTexHandle(mWidth, mHeight, GFXFormatR32F,
     &GFXRenderTargetProfile, avar("%s() - mDepthBuffer (line %d)", __FUNCTION__, __LINE__));
     if (!mDepthBuffer.isValid())
     {
        Con::errorf("VolumetricFogRTManager Fatal Error: Unable to create Depthbuffer");
        return false;
     }
     if (!mDepthTarget.registerWithName("volfogdepth"))
     {
        Con::errorf("VolumetricFogRTManager Fatal Error : Unable to register Depthbuffer");
        return false;
     }
     mDepthTarget.setTexture(mDepthBuffer);
     
     mFrontBuffer = GFXTexHandle(mWidth, mHeight, GFXFormatR32F,
     &GFXRenderTargetProfile, avar("%s() - mFrontBuffer (line %d)", __FUNCTION__, __LINE__));
     if (!mFrontBuffer.isValid())
     {
        Con::errorf("VolumetricFogRTManager Fatal Error: Unable to create front buffer");
        return false;
     }
     if (!mFrontTarget.registerWithName("volfogfront"))
     {
        Con::errorf("VolumetricFogRTManager Fatal Error : Unable to register Frontbuffer");
        return false;
     }
     
     mFrontTarget.setTexture(mFrontBuffer);
     
     Con::setVariable("$VolumetricFog::density", "0.0");
     
     mIsInitialized = true;
     
     return true;
  }
     
  U32 VolumetricFogRTManager::IncFogObjects()
  {
     mNumFogObjects++;
     return mNumFogObjects;
  }
     
  U32 VolumetricFogRTManager::DecFogObjects()
  {
     if (mNumFogObjects > 0)
        mNumFogObjects--;
     return mNumFogObjects;
  }
     
  void VolumetricFogRTManager::ResizeRT( WindowId did, S32 width, S32 height )
  {
     smVolumetricFogRTMResizeSignal.trigger(this, true);
  }
     
  void VolumetricFogRTManager::FogAnswered()
  {
     if (Resize())
        smVolumetricFogRTMResizeSignal.trigger(this, false);
     else
        Con::errorf("VolumetricFogRTManager::FogAnswered - Error resizing rendertargets!");
  }
     
  bool VolumetricFogRTManager::Resize()
  {
     if (mTargetScale < 1 || GFX->getAdapterType() == Direct3D11)
        mTargetScale = 1;
  
     mWidth = mFloor(mPlatformWindow->getClientExtent().x / mTargetScale);
     mHeight = mFloor(mPlatformWindow->getClientExtent().y / mTargetScale);
     
     if (mWidth < 16 || mHeight < 16)
        return false;
     
     if (mFrontTarget.isRegistered())
        mFrontTarget.setTexture(NULL);
     
     if (mDepthTarget.isRegistered())
        mDepthTarget.setTexture(NULL);
     
     if (mDepthBuffer.isValid())
        mDepthBuffer->kill();
     
     if (mFrontBuffer.isValid())
        mFrontBuffer->kill();
     
     mFrontBuffer = GFXTexHandle(mWidth, mHeight, GFXFormatR32F,
     &GFXRenderTargetProfile, avar("%s() - mFrontBuffer (line %d)", __FUNCTION__, __LINE__));
     if (!mFrontBuffer.isValid())
     {
        Con::errorf("VolumetricFogRTManager::Resize() Fatal Error: Unable to create front buffer");
        return false;
     }
     mFrontTarget.setTexture(mFrontBuffer);
     
     mDepthBuffer = GFXTexHandle(mWidth, mHeight, GFXFormatR32F,
     &GFXRenderTargetProfile, avar("%s() - mDepthBuffer (line %d)", __FUNCTION__, __LINE__));
     if (!mDepthBuffer.isValid())
     {
        Con::errorf("VolumetricFogRTManager::Resize() Fatal Error: Unable to create Depthbuffer");
        return false;
     }
     mDepthTarget.setTexture(mDepthBuffer);
     return true;
  }
     
  S32 VolumetricFogRTManager::setQuality(U32 Quality)
  {
     if (!mIsInitialized)
        return (mTargetScale = Quality);
        
     if (Quality < 1)
        Quality = 1;
     
     if (Quality == mTargetScale)
        return mTargetScale;
     
     mTargetScale = Quality;
     
     smVolumetricFogRTMResizeSignal.trigger(this, true);
     
     return mTargetScale;
  }
     
  VolumetricFogRTManager* VolumetricFogRTManager::get()
  {
     return gVolumetricFogRTManager;
  }
     
  DefineEngineFunction(SetFogVolumeQuality, S32, (U32 new_quality), ,
  "@brief Resizes the rendertargets of the Volumetric Fog object.\n"
  "@params new_quality new quality for the rendertargets 1 = full size, 2 = halfsize, 3 = 1/3, 4 = 1/4 ...")
  {
     if (VFRTM == NULL)
        return -1;
     return VFRTM->setQuality(new_quality);
  }
  