text: /*
  -----------------------------------------------------------------------------
  This source file is part of OGRE
  (Object-oriented Graphics Rendering Engine)
  For the latest info, see http://www.ogre3d.org/
  
  Copyright (c) 2000-2011 Torus Knot Software Ltd
  
  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.
  -----------------------------------------------------------------------------
  */
  
  #include "OgreHeightmapTerrainPageSource.h"
  #include "OgreTerrainPage.h"
  #include "OgreException.h"
  #include "OgreStringConverter.h"
  #include "OgreTerrainSceneManager.h"
  #include "OgreResourceManager.h"
  #include "OgreLogManager.h"
  
  namespace Ogre {
  
      //-------------------------------------------------------------------------
      HeightmapTerrainPageSource::HeightmapTerrainPageSource()
          : mIsRaw(false), mFlipTerrain(false), mPage(0)
      {
      }
      //-------------------------------------------------------------------------
      HeightmapTerrainPageSource::~HeightmapTerrainPageSource()
      {
          shutdown();
      }
      //-------------------------------------------------------------------------
      void HeightmapTerrainPageSource::shutdown(void)
      {
          // Image will destroy itself
          OGRE_DELETE mPage;
          mPage = 0;
      }
      //-------------------------------------------------------------------------
      void HeightmapTerrainPageSource::loadHeightmap(void)
      {
          size_t imgSize;
          // Special-case RAW format
          if (mIsRaw)
          {
              // Image size comes from setting (since RAW is not self-describing)
              imgSize = mRawSize;
              
              // Load data
              mRawData.setNull();
              DataStreamPtr stream = 
                  ResourceGroupManager::getSingleton().openResource(
                      mSource, ResourceGroupManager::getSingleton().getWorldResourceGroupName());
              mRawData = MemoryDataStreamPtr(OGRE_NEW MemoryDataStream(mSource, stream));
  
              // Validate size
              size_t numBytes = imgSize * imgSize * mRawBpp;
              if (mRawData->size() != numBytes)
              {
                  shutdown();
                  OGRE_EXCEPT(Exception::ERR_INVALIDPARAMS, 
                      "RAW size (" + StringConverter::toString(mRawData->size()) + 
                      ") does not agree with configuration settings.", 
                      "HeightmapTerrainPageSource::loadHeightmap");
              }
          }
          else
          {
              mImage.load(mSource, ResourceGroupManager::getSingleton().getWorldResourceGroupName());
              // Must be square (dimensions checked later)
              if ( mImage.getWidth() != mImage.getHeight())
              {
                  shutdown();
                  OGRE_EXCEPT(Exception::ERR_INVALIDPARAMS,
                      "Heightmap must be square",
                      "HeightmapTerrainPageSource::loadHeightmap");
              }
              imgSize = mImage.getWidth();
          }
          //check to make sure it's the expected size
          if ( imgSize != mPageSize)
          {
              shutdown();
              String err = "Error: Invalid heightmap size : " +
                  StringConverter::toString( imgSize ) +
                  ". Should be " + StringConverter::toString(mPageSize);
              OGRE_EXCEPT( Exception::ERR_INVALIDPARAMS, err, 
                  "HeightmapTerrainPageSource::loadHeightmap" );
          }
  
      }
      //-------------------------------------------------------------------------
      void HeightmapTerrainPageSource::initialise(TerrainSceneManager* tsm, 
          ushort tileSize, ushort pageSize, bool asyncLoading, 
          TerrainPageSourceOptionList& optionList)
      {
          // Shutdown to clear any previous data
          shutdown();
  
          TerrainPageSource::initialise(tsm, tileSize, pageSize, asyncLoading, optionList);
  
          // Get source image
          TerrainPageSourceOptionList::iterator ti, tiend;
          tiend = optionList.end();
          bool imageFound = false;
          mIsRaw = false;
          bool rawSizeFound = false;
          bool rawBppFound = false;
          for (ti = optionList.begin(); ti != tiend; ++ti)
          {
              String val = ti->first;
              StringUtil::trim(val);
              if (StringUtil::startsWith(val, "Heightmap.image", false))
              {
                  mSource = ti->second;
                  imageFound = true;
                  // is it a raw?
                  if (StringUtil::endsWith(mSource, "raw"))
                  {
                      mIsRaw = true;
                  }
              }
              else if (StringUtil::startsWith(val, "Heightmap.raw.size", false))
              {
                  mRawSize = atoi(ti->second.c_str());
                  rawSizeFound = true;
              }
              else if (StringUtil::startsWith(val, "Heightmap.raw.bpp", false))
              {
                  mRawBpp = atoi(ti->second.c_str());
                  if (mRawBpp < 1 || mRawBpp > 2)
                  {
                      OGRE_EXCEPT(Exception::ERR_INVALIDPARAMS, 
                          "Invalid value for 'Heightmap.raw.bpp', must be 1 or 2",
                          "HeightmapTerrainPageSource::initialise");
                  }
                  rawBppFound = true;
              }
              else if (StringUtil::startsWith(val, "Heightmap.flip", false))
              {
                  mFlipTerrain = StringConverter::parseBool(ti->second);
              }
              else
              {
                  LogManager::getSingleton().logMessage("Warning: ignoring unknown Heightmap option '"
                      + val + "'");
              }
          }
          if (!imageFound)
          {
              OGRE_EXCEPT(Exception::ERR_ITEM_NOT_FOUND, 
                  "Missing option 'Heightmap.image'", 
                  "HeightmapTerrainPageSource::initialise");
          }
          if (mIsRaw && 
              (!rawSizeFound || !rawBppFound))
          {
              OGRE_EXCEPT(Exception::ERR_ITEM_NOT_FOUND, 
                  "Options 'Heightmap.raw.size' and 'Heightmap.raw.bpp' must "
                  "be specified for RAW heightmap sources", 
                  "HeightmapTerrainPageSource::initialise");
          }
          // Load it!
          loadHeightmap();
      }
      //-------------------------------------------------------------------------
      void HeightmapTerrainPageSource::requestPage(ushort x, ushort y)
      {
          // Only 1 page provided
          if (x == 0 && y == 0 && !mPage)
          {
              // Convert the image data to unscaled floats
              ulong totalPageSize = mPageSize * mPageSize; 
              Real *heightData = OGRE_ALLOC_T(Real, totalPageSize, MEMCATEGORY_RESOURCE);
              const uchar* pOrigSrc, *pSrc;
              Real* pDest = heightData;
              Real invScale;
              bool is16bit = false;
              
              if (mIsRaw)
              {
                  pOrigSrc = mRawData->getPtr();
                  is16bit = (mRawBpp == 2);
              }
              else
              {
                  PixelFormat pf = mImage.getFormat();
                  if (pf != PF_L8 && pf != PF_L16)
                  {
                      OGRE_EXCEPT( Exception::ERR_INVALIDPARAMS, 
                          "Error: Image is not a grayscale image.",
                          "HeightmapTerrainPageSource::requestPage" );
                  }
  
                  pOrigSrc = mImage.getData();
                  is16bit = (pf == PF_L16);
              }
              // Determine mapping from fixed to floating
              ulong rowSize;
              if ( is16bit )
              {
                  invScale = 1.0f / 65535.0f; 
                  rowSize =  mPageSize * 2;
              }
              else 
              {
                  invScale = 1.0f / 255.0f; 
                  rowSize =  mPageSize;
              }
              // Read the data
              pSrc = pOrigSrc;
              for (ulong j = 0; j < mPageSize; ++j)
              {
                  if (mFlipTerrain)
                  {
                      // Work backwards 
                      pSrc = pOrigSrc + (rowSize * (mPageSize - j - 1));
                  }
                  for (ulong i = 0; i < mPageSize; ++i)
                  {
                      if (is16bit)
                      {
                          #if OGRE_ENDIAN == OGRE_ENDIAN_BIG
                              ushort val = *pSrc++ << 8;
                              val += *pSrc++;
                          #else
                              ushort val = *pSrc++;
                              val += *pSrc++ << 8;
                          #endif
                          *pDest++ = Real(val) * invScale;
                      }
                      else
                      {
                          *pDest++ = Real(*pSrc++) * invScale;
                      }
                  }
              }
  
              // Call listeners
              firePageConstructed(0, 0, heightData);
              // Now turn into TerrainPage
              // Note that we're using a single material for now
              if (mSceneManager)
              {
                  mPage = buildPage(heightData, 
                      mSceneManager->getOptions().terrainMaterial);
                  mSceneManager->attachPage(0, 0, mPage);
              }
  
              // Free temp store
              OGRE_FREE(heightData, MEMCATEGORY_RESOURCE);
          }
      }
      //-------------------------------------------------------------------------
      void HeightmapTerrainPageSource::expirePage(ushort x, ushort y)
      {
          // Single page
          if (x == 0 && y == 0 && mPage)
          {
              OGRE_DELETE mPage;
              mPage = 0;
          }
  
      }
      //-------------------------------------------------------------------------
  
  
  }
  