C++ Image::resize方法代码示例

	void SnowTerrain::initBlendMaps(Terrain* terrain)
	{
		TextureLayerFileList blendImages = mSnowConfig->terrainSettings.textureBlendFileList;

		// load those blendmaps into the layers
		for(int j = 0;j < terrain->getLayerCount();j++)
		{
			// skip first layer
			if(j==0)
				continue;

			// no blend map for this layer
			if(blendImages.size() >= j && blendImages[j].length() == 0)
				continue;

			Ogre::TerrainLayerBlendMap *blendmap = terrain->getLayerBlendMap(j);
			Ogre::Image img;

			img.load(blendImages[j],"General");
			int blendmapsize = terrain->getLayerBlendMapSize();
			if(img.getWidth() != blendmapsize)
				img.resize(blendmapsize, blendmapsize);

			float *ptr = blendmap->getBlendPointer();
			Ogre::uint8 *data = static_cast<Ogre::uint8*>(img.getPixelBox().data);

			for(int bp = 0;bp < blendmapsize * blendmapsize;bp++)
				ptr[bp] = static_cast<float>(data[bp]) / 255.0f;

			blendmap->dirty();
			blendmap->update();
		}
	}

//.........这里部分代码省略.........
#include <fstream>
#include <ctime>

//****************************************************************************/
TextureLayer::TextureLayer(void) :
    mTextureOnWhichIsPaintedWidth(0),
    mTextureOnWhichIsPaintedHeight(0),
    mTextureOnWhichIsPaintedHasAlpha(false),
    mNumMipMaps(0),
    mTextureTypeDefined(false),
    mMaxSequence(0)
{
    mTextureType = Ogre::PBSM_DIFFUSE;
    mDatablockId = "";
    mTextureFileName = "";
}

//****************************************************************************/
TextureLayer::~TextureLayer(void)
{
}

//****************************************************************************/
void TextureLayer::setDatablockIdAndTexture (const Ogre::IdString& datablockId,
                                             Ogre::PbsTextureTypes textureType,
                                             const Ogre::String& textureFileName)
{
    mDatablockId = datablockId;
    mTextureType = textureType;
    mTextureFileName = textureFileName;
    mTextureTypeDefined = true;

    // Load the texture as image; assume it can be loaded, because it was already loaded as part of the material
    setFirstTextureGeneration();

    // Create the pixelbox of the original texture; this MUST be a separate image
    mOriginalTexture.load(textureFileName, Ogre::ResourceGroupManager::DEFAULT_RESOURCE_GROUP_NAME);
    mPixelboxOriginalTexture = mOriginalTexture.getPixelBox(0, 0);

    // Debug texture
    //Ogre::LogManager::getSingleton().logMessage("Debug texture: " + textureFileName);
    //Ogre::LogManager::getSingleton().logMessage("Depth: " + Ogre::StringConverter::toString(mOriginalTexture.getDepth()));
    //Ogre::LogManager::getSingleton().logMessage("Pixel format: " + Ogre::StringConverter::toString(mOriginalTexture.getFormat()));
    //Ogre::LogManager::getSingleton().logMessage("Alpha: " + Ogre::StringConverter::toString(mOriginalTexture.getHasAlpha()));
    //Ogre::LogManager::getSingleton().logMessage("Height: " + Ogre::StringConverter::toString(mOriginalTexture.getHeight()));
    //Ogre::LogManager::getSingleton().logMessage("Number of faces: " + Ogre::StringConverter::toString(mOriginalTexture.getNumFaces()));
    //Ogre::LogManager::getSingleton().logMessage("Number of mipmaps: " + Ogre::StringConverter::toString(mOriginalTexture.getNumMipmaps()));
    //Ogre::LogManager::getSingleton().logMessage("Width: " + Ogre::StringConverter::toString(mOriginalTexture.getWidth()));
}

//****************************************************************************/
void TextureLayer::blitTexture (void)
{
    /* Always get the actual pointers, because they may change. That is the reason why the datablock pointer cannot be cached.
     * The same seems to apply to the texture pointer.
     */
    Ogre::HlmsDatablock* datablock;
    Ogre::HlmsPbsDatablock* datablockPbs;
    Ogre::TexturePtr texture;
    Ogre::HlmsManager* hlmsManager = Ogre::Root::getSingletonPtr()->getHlmsManager();
    Ogre::HlmsPbs* hlmsPbs = static_cast<Ogre::HlmsPbs*>(hlmsManager->getHlms(Ogre::HLMS_PBS));
    datablock = hlmsPbs->getDatablock(mDatablockId);
    if (!datablock)
        return;

    datablockPbs = static_cast<Ogre::HlmsPbsDatablock*>(datablock);
    try
    {
        // Get texture on GPU
        if (!datablockPbs->getTexture(mTextureType).isNull())
        {
            texture = datablockPbs->getTexture(mTextureType); // TextureType MUST exist, otherwise the application crashes
            mNumMipMaps = texture->getNumMipmaps();
        }
    }
    catch (Ogre::Exception e){}

    if (texture.isNull())
        return;

    Ogre::uint8 maxMipMaps = mNumMipMaps + 1; // Increase with one, because there is always one image to blit
    maxMipMaps = maxMipMaps > PAINT_MAX_MIP_MAPS ? PAINT_MAX_MIP_MAPS : maxMipMaps; // Just paint a few mipmaps (not all)
    Ogre::Image textureOnWhichIsPaintedScaled = mTextureOnWhichIsPainted; // Temporary image must be used, otherwise painting doesn't work
    size_t w = mTextureOnWhichIsPaintedWidth;
    size_t h = mTextureOnWhichIsPaintedHeight;
    Ogre::v1::HardwarePixelBuffer* buffer;
    for (Ogre::uint8 i = 0; i < maxMipMaps; ++i)
    {
        buffer = texture->getBuffer(0, i).getPointer();
        buffer->blitFromMemory(textureOnWhichIsPaintedScaled.getPixelBox(0, 0), Ogre::Box(0, 0, 0, w, h, 1));
        w*=0.5f; // Mipmaps always are half of the previous one
        h*=0.5f;
        if (w < 1.0f || h < 1.0f)
            break; // Stop when the mipmaps are too small

        textureOnWhichIsPaintedScaled.resize(w, h);

    }
    textureOnWhichIsPaintedScaled.freeMemory();
}

void DotSceneLoader::processBlendmaps(rapidxml::xml_node<>* XMLNode)
{
    int pageX = Ogre::StringConverter::parseInt(XMLNode->first_attribute("pageX")->value());
    int pageY = Ogre::StringConverter::parseInt(XMLNode->first_attribute("pageY")->value());

    Ogre::String filename = mTerrainGroup->generateFilename(pageX, pageY);
    // skip this is terrain page has been saved already
    if (!Ogre::ResourceGroupManager::getSingleton().resourceExists(mTerrainGroup->getResourceGroup(), filename))
    {
        rapidxml::xml_node<>* pElement;

        // Process blendmaps (*)
        std::vector<Ogre::String> blendMaps;
        rapidxml::xml_node<>* pBlendmap;
        pElement = XMLNode->first_node("blendMaps");
        pBlendmap = pElement->first_node("blendMap");
        while(pBlendmap)
        {
            blendMaps.push_back(getAttrib(pBlendmap, "texture",""));
            pBlendmap = pBlendmap->next_sibling("blendMap");
        }

        for(int j = 1;j < mTerrainGroup->getTerrain(pageX, pageY)->getLayerCount();j++)
        {
            Ogre::TerrainLayerBlendMap *blendmap = mTerrainGroup->getTerrain(pageX, pageY)->getLayerBlendMap(j);
            Ogre::Image img;
            img.load(blendMaps[j-1],"General");
            int blendmapsize = mTerrainGroup->getTerrain(pageX, pageY)->getLayerBlendMapSize();
            if(img.getWidth() != blendmapsize)
                img.resize(blendmapsize, blendmapsize);

            float *ptr = blendmap->getBlendPointer();
            Ogre::uint8 *data = static_cast<Ogre::uint8*>(img.getPixelBox().data);

            for(int bp = 0;bp < blendmapsize * blendmapsize;bp++)
                ptr[bp] = static_cast<float>(data[bp]) / 255.0f;

            blendmap->dirty();
            blendmap->update();
        }
    }
}

void TerrainGeometryManager::initBlendMaps(int x, int z, Ogre::Terrain* terrain )
{
	bool debugBlendMaps = BOPT("DebugBlendMaps", false);

	int layerCount = terrain->getLayerCount();
	for (int i = 1; i < layerCount; i++)
	{
		blendLayerInfo_t &bi = blendInfo[i];

		if(bi.blendMapTextureFilename.empty()) continue;

		Ogre::Image img;
		//std::pair<uint8,uint8> textureIndex = terrain->getLayerBlendTextureIndex(i);
		//uint8 bti = terrain->getBlendTextureIndex(i);
		try
		{
			img.load(bi.blendMapTextureFilename, ResourceGroupManager::AUTODETECT_RESOURCE_GROUP_NAME);
		} catch(Exception &e)
		{
			LOG("Error loading blendmap: " + bi.blendMapTextureFilename + " : " + e.getFullDescription());
			continue;
		}

		TerrainLayerBlendMap *blendmap = terrain->getLayerBlendMap(i);

		// resize that blending map so it will fit
		Ogre::uint32 blendmapSize = terrain->getLayerBlendMapSize();
		if (img.getWidth() != blendmapSize)
			img.resize(blendmapSize, blendmapSize);

		// now to the ugly part
		float* ptr = blendmap->getBlendPointer();
		for (Ogre::uint32 z = 0; z != blendmapSize; z++)
		{
			for (Ogre::uint32 x = 0; x != blendmapSize; x++)
			{
				Ogre::ColourValue c = img.getColourAt(x, z, 0);
				float alpha = bi.alpha;
				if      (bi.blendMode == 'R')
					*ptr++ = c.r * alpha;
				else if (bi.blendMode == 'G')
					*ptr++ = c.g * alpha;
				else if (bi.blendMode == 'B')
					*ptr++ = c.b * alpha;
				else if (bi.blendMode == 'A')
					*ptr++ = c.a * alpha;
			}
		}
		blendmap->dirty();
		blendmap->update();
	}

	if (debugBlendMaps)
	{
		for (int i = 1; i < layerCount; i++)
		{
			Ogre::TerrainLayerBlendMap* blendMap = terrain->getLayerBlendMap(i);
			Ogre::uint32 blendmapSize = terrain->getLayerBlendMapSize();
			Ogre::Image img;
			unsigned short *idata = OGRE_ALLOC_T(unsigned short, blendmapSize * blendmapSize, Ogre::MEMCATEGORY_RESOURCE);
			float scale = 65535.0f;
			for (unsigned int x = 0; x < blendmapSize; x++)
				for (unsigned int z = 0; z < blendmapSize; z++)
					idata[x + z * blendmapSize] = (unsigned short)(blendMap->getBlendValue(x, blendmapSize - z) * scale);
			img.loadDynamicImage((Ogre::uchar*)(idata), blendmapSize, blendmapSize, Ogre::PF_L16);
			std::string fileName = "blendmap_layer_" + Ogre::StringConverter::toString(i) + ".png";
			img.save(fileName);
			OGRE_FREE(idata, Ogre::MEMCATEGORY_RESOURCE);
		}
	}
}

	Vector4* SnowTerrain::getTerrainNormalData()
	{
		PixelBox* terrainNormals;

		// load from normals file
		if(mSnowConfig->terrainSettings.normalsDataFile.length() > 0)
		{
			// get terrain normal data using image
			Ogre::Image img;
			img.load(mSnowConfig->terrainSettings.normalsDataFile,  "General");
			//img.flipAroundY();
			//img.flipAroundX();

			size_t size = img.getWidth();
			assert(img.getWidth() == img.getHeight());

			if (img.getWidth() != mTerrainSize || img.getHeight() != mTerrainSize)
				img.resize(mTerrainSize, mTerrainSize);

			terrainNormals = &img.getPixelBox();

			Vector4* floats = convertNormalsToFloats(terrainNormals, true);
			//OGRE_FREE(terrainNormals->data, Ogre::MEMCATEGORY_GENERAL);
			
			// need to swap z and y vector due to different vertical axis in normal map and world space!
			for(size_t i = 0;i<mTerrainSize*mTerrainSize;i++)
			{
				Vector4 v = floats[i];
				floats[i].z = v.y;
				floats[i].y = v.z;

			}
			return floats;
		}
		else
		{
			// need to wait until terrain is loaded
			while (getTerrain()->isDerivedDataUpdateInProgress())
			{
				// we need to wait for this to finish
				OGRE_THREAD_SLEEP(50);
				Root::getSingleton().getWorkQueue()->processResponses();
			}

			// Get terrain normal data using official method
			//terrainNormals = getTerrain()->calculateNormals(Ogre::Rect(0,0,mTerrainSize,mTerrainSize),Rect(0,0,mTerrainSize,mTerrainSize));
			Ogre::Image img;
			getTerrain()->getTerrainNormalMap()->convertToImage(img);
			//img.flipAroundY();
			img.flipAroundX();
			//img.save("test_normals.bmp");
			terrainNormals = &img.getPixelBox();

			Vector4* floats = convertNormalsToFloats(terrainNormals, true);
			//OGRE_FREE(terrainNormals->data, Ogre::MEMCATEGORY_GENERAL);
			return floats;
		}


		
	}

void 
BrushSelector::buildPreviewBitmap( const Fairy::TextureInfo texInfo )
{
    const Ogre::uchar BytePerPixel = 8;

    // 读取原始image
    Ogre::Image *oriImage = GetSceneManipulator()->getPreviewImage(texInfo.ownerTextureName);
    // 源大纹理的大小
    size_t oriImageHeight = oriImage->getHeight();
    size_t oriImageWidth = oriImage->getWidth();

    Ogre::uchar *oriImageData = oriImage->getData();
    // 所选纹理的大小
    size_t newImageWidth = texInfo.width*TexTileSize;
    size_t newImageHeight = texInfo.height*TexTileSize;

    // 分配一个足够大的空间来保存新建的image的数据
    size_t newImagegetRowSpan = newImageWidth*oriImage->getBPP()/BytePerPixel;  // 新建的image的行宽（单位为字节）
    Ogre::uchar *newImageData = OGRE_ALLOC_T(Ogre::uchar, oriImageHeight*newImagegetRowSpan, Ogre::MEMCATEGORY_GENERAL);//new Ogre::uchar[newImageHeight*newImagegetRowSpan];
    
    Ogre::uchar *newImageDataPointer = newImageData;
    // 得知起始像素点
    size_t startPoint = ( oriImageWidth * texInfo.topCorner + texInfo.leftCorner )
        * TexTileSize * oriImage->getBPP()/BytePerPixel;

    Ogre::uchar *oriImagedataPointer = oriImageData + startPoint;

    // 把所选的纹理的数据提取出来，并创建一个新的image
    for ( Ogre::uint i=0; i<newImageHeight; ++i )
    {
        memcpy(newImageDataPointer, oriImagedataPointer, newImagegetRowSpan);
        newImageDataPointer += newImagegetRowSpan;
        oriImagedataPointer += oriImage->getRowSpan();
    }

    Ogre::Image newImage;
    newImage.loadDynamicImage(newImageData,newImageWidth,newImageHeight,1,oriImage->getFormat(),true);

    // 如果所选纹理大于64*64，就先resize
    if ( texInfo.width > 1 || texInfo.height > 1 )
        newImage.resize(mPreviewImageWidth, mPreviewImageHeight);

    // 如果有alpha，要与黑白图进行混合
    if ( newImage.getHasAlpha() )
    {  
		Ogre::ColourValue col;

		for ( int i=0; i<mPreviewImageWidth; ++i )
		{
			for ( int j=0; j<mPreviewImageWidth; ++j )
			{
				col = newImage.getColourAt(j,i,0);

				float alphaValue = col.a;

				unsigned char r = col.r*255 * alphaValue + mBlackWhitePreviewImage.GetRed(i,j) * ( 1.0f - alphaValue);
				unsigned char g = col.g*255 * alphaValue + mBlackWhitePreviewImage.GetGreen(i,j) * ( 1.0f - alphaValue);
				unsigned char b = col.b*255 * alphaValue + mBlackWhitePreviewImage.GetBlue(i,j) * ( 1.0f - alphaValue);

				// 设置到image中
				mCurrentPreviewImage.SetRGB(j,i,r,g,b);
			}
		}
        // 设置到缩略图控件中
        mBrushesPreview->SetBitmap(mCurrentPreviewImage);
    }
    // 没有alpha，就直接拷贝数据
    else
    {
		Ogre::ColourValue col;

		for ( int i=0; i<mPreviewImageWidth; ++i )
		{
			for ( int j=0; j<mPreviewImageWidth; ++j )
			{
				col = newImage.getColourAt(j,i,0);

				unsigned char r = col.r*255;
				unsigned char g = col.g*255;
				unsigned char b = col.b*255;

				// 设置到image中
				mCurrentPreviewImage.SetRGB(j,i,r,g,b);
			}
		}

        mBrushesPreview->SetBitmap(mCurrentPreviewImage);    
    }
}

void NavViewPanel::displayMap(const nav_msgs::OccupancyGrid& map)
{
  boost::mutex::scoped_lock lock(map_lock_);

  map_resolution_ = map.info.resolution;

  // Pad dimensions to power of 2
  map_width_ = map.info.width;//(int)pow(2,ceil(log2(map.info.width)));
  map_height_ = map.info.height;//(int)pow(2,ceil(log2(map.info.height)));
  map_origin_x_ = map.info.origin.position.x;
  map_origin_y_ = map.info.origin.position.y;

  //ROS_INFO("Padded dimensions to %d X %d\n", map_width_, map_height_);

  // Expand it to be RGB data
  int pixels_size = map_width_ * map_height_ * 3;
  unsigned char* pixels = new unsigned char[pixels_size];
  memset(pixels, 255, pixels_size);

  for(unsigned int j=0;j<map.info.height;j++)
  {
    for(unsigned int i=0;i<map.info.width;i++)
    {
      unsigned char val;
      if(map.data[j*map.info.width+i] == 100)
        val = 0;
      else if(map.data[j*map.info.width+i] == 0)
        val = 255;
      else
        val = 127;

      int pidx = 3*(j*map_width_ + i);
      pixels[pidx+0] = val;
      pixels[pidx+1] = val;
      pixels[pidx+2] = val;
    }
  }

  Ogre::DataStreamPtr pixel_stream;
  pixel_stream.bind(new Ogre::MemoryDataStream( pixels, pixels_size ));
  static int tex_count = 0;
  std::stringstream ss;
  ss << "NavViewMapTexture" << tex_count++;
  try
  {
    map_texture_ = Ogre::TextureManager::getSingleton().loadRawData( ss.str(), Ogre::ResourceGroupManager::DEFAULT_RESOURCE_GROUP_NAME,
                                                                   pixel_stream, map_width_, map_height_, Ogre::PF_BYTE_RGB, Ogre::TEX_TYPE_2D,
                                                                   0);
  }
  catch(Ogre::RenderingAPIException&)
  {
    Ogre::Image image;
    pixel_stream->seek(0);
    float width = map_width_;
    float height = map_height_;
    if (map_width_ > map_height_)
    {
      float aspect = height / width;
      width = 2048;
      height = width * aspect;
    }
    else
    {
      float aspect = width / height;
      height = 2048;
      width = height * aspect;
    }

    ROS_WARN("Failed to create full-size map texture, likely because your graphics card does not support textures of size > 2048.  Downsampling to [%d x %d]...", (int)width, (int)height);
    image.loadRawData(pixel_stream, map_width_, map_height_, Ogre::PF_BYTE_RGB);
    image.resize(width, height, Ogre::Image::FILTER_NEAREST);
    ss << "Downsampled";
    map_texture_ = Ogre::TextureManager::getSingleton().loadImage(ss.str(), Ogre::ResourceGroupManager::DEFAULT_RESOURCE_GROUP_NAME, image);
  }

  delete [] pixels;

  Ogre::SceneNode* map_node = NULL;
  if ( !map_object_ )
  {
    static int map_count = 0;
    std::stringstream ss;
    ss << "NavViewMapObject" << map_count++;
    map_object_ = scene_manager_->createManualObject( ss.str() );
    map_node = root_node_->createChildSceneNode();
    map_node->attachObject( map_object_ );

    ss << "Material";
    map_material_ = Ogre::MaterialManager::getSingleton().create( ss.str(), Ogre::ResourceGroupManager::DEFAULT_RESOURCE_GROUP_NAME );
    map_material_->setReceiveShadows(false);
    map_material_->getTechnique(0)->setLightingEnabled(false);
  }
  else
  {
    map_node = map_object_->getParentSceneNode();
  }

  Ogre::Pass* pass = map_material_->getTechnique(0)->getPass(0);
  Ogre::TextureUnitState* tex_unit = NULL;
  if (pass->getNumTextureUnitStates() > 0)
//.........这里部分代码省略.........

void 
MaterialPreviewDialog::buildPreviewBitmap( const Ogre::String &texName )
{
	const Ogre::uchar BytePerPixel = 8;

	// 读取原始image
	Ogre::Image *oriImage = getPreviewImage(texName);
	// 源大纹理的大小
	size_t oriImageHeight = oriImage->getHeight();
	size_t oriImageWidth = oriImage->getWidth();

	Ogre::uchar *oriImageData = oriImage->getData();

	// 分配一个足够大的空间来保存新建的image的数据
	size_t newImagegetRowSpan = oriImageWidth*oriImage->getBPP()/BytePerPixel;  // 新建的image的行宽（单位为字节）
	Ogre::uchar *newImageData = new Ogre::uchar[oriImageHeight*newImagegetRowSpan];

	Ogre::uchar *newImageDataPointer = newImageData;

	Ogre::uchar *oriImagedataPointer = oriImageData;

	// 把所选的纹理的数据提取出来，并创建一个新的image
	for ( Ogre::uint i=0; i<oriImageHeight; ++i )
	{
		memcpy(newImageDataPointer, oriImagedataPointer, newImagegetRowSpan);
		newImageDataPointer += newImagegetRowSpan;
		oriImagedataPointer += oriImage->getRowSpan();
	}

	Ogre::Image newImage;
	newImage.loadDynamicImage(newImageData,oriImageWidth,oriImageHeight,1,oriImage->getFormat(),true);

	// 如果所选纹理大于64*64，就先resize
	if ( oriImageWidth > mPreviewImageWidth || oriImageHeight > mPreviewImageHeight )
		newImage.resize(mPreviewImageWidth, mPreviewImageHeight);

	// 如果有alpha，要与黑白图进行混合
	if ( newImage.getHasAlpha() )
	{
		Ogre::uchar *tempPtr = newImage.getData();

		assert (tempPtr);

		for ( size_t i=0; i<mPreviewImageHeight; ++i )
			for ( size_t j=0; j<mPreviewImageWidth; ++j )
			{
				// 取出alpha值
				float alphaValue = (float)tempPtr[3] / 255.0f;

				// 计算出经过alpha混合后的颜色值
				unsigned char r = tempPtr[2] * alphaValue;
				unsigned char g = tempPtr[1] * alphaValue;
				unsigned char b = tempPtr[0] * alphaValue;

				// 设置到image中
				mCurrentPreviewImage.SetRGB(j,i,r,g,b);
				tempPtr += 4;
			}

			// 要把指针移回到图片数据的
			tempPtr -= mPreviewImageHeight * mPreviewImageWidth * 4;
			// 设置到缩略图控件中
	}
	// 没有alpha，就直接拷贝数据
	else
	{
		memcpy ( mCurrentPreviewImage.GetData(), newImage.getData(), newImage.getSize() );
	}
}

//.........这里部分代码省略.........
	}

	// Terrain initialization
	Ogre::TerrainGlobalOptions* terrainglobals = OGRE_NEW Ogre::TerrainGlobalOptions();
	terrainglobals->setMaxPixelError(1);
	//terrainglobals->setCompositeMapDistance(30000);
	//terrainglobals->setLightMapDirection(lightdir);
    //terrainglobals->setCompositeMapAmbient(scenemgr->getAmbientLight());
    //terrainglobals->setCompositeMapDiffuse(l->getDiffuseColour());
	
	Ogre::TerrainMaterialGeneratorA::SM2Profile* pMatProfile = 
      static_cast<Ogre::TerrainMaterialGeneratorA::SM2Profile*>(terrainglobals->getDefaultMaterialGenerator()->getActiveProfile());
	
	pMatProfile->setLightmapEnabled(false);
	pMatProfile->setCompositeMapEnabled(false);
	
	Ogre::TerrainGroup* terraingroup = OGRE_NEW Ogre::TerrainGroup(scenemgr, Ogre::Terrain::ALIGN_X_Z, terrainsize, worldsize);
    terraingroup->setFilenameConvention(Ogre::String("terrain"), Ogre::String("ogt"));
    terraingroup->setOrigin(Ogre::Vector3::ZERO);
		
	Ogre::Terrain* terrain = OGRE_NEW Ogre::Terrain(scenemgr);

	// terrainsettings							
	Ogre::Terrain::ImportData& imp = terraingroup->getDefaultImportSettings();	
	imp.terrainSize = terrainsize;
	imp.worldSize = worldsize;
	imp.minBatchSize = 33;
	imp.maxBatchSize = 65;

	// use float RAW heightmap as input
	imp.inputFloat = buffer;
	
	// process texture layers
	imp.layerList.resize(layercount);
	Ogre::StringVector blendmaps(layercount);
	for(int i=0;i<layercount;i++)
	{
		// load layer info
		Ogre::String sectionStr = Ogre::StringConverter::toString(i);
		Ogre::Real layerworldsize = Ogre::StringConverter::parseReal(terrainconfig->getSetting("worldsize", sectionStr));
		
		if (i==0)
		{			
			// no blendmap at layer 0 (baselayer)
			Ogre::String specular = terrainconfig->getSetting("specular", sectionStr);
			Ogre::String normal = terrainconfig->getSetting("normal", sectionStr);

			// add layer		
			imp.layerList[i].textureNames.push_back(specular);
			imp.layerList[i].textureNames.push_back(normal);
			imp.layerList[i].worldSize = layerworldsize;			
		}
		else
		{
			Ogre::String specular = terrainconfig->getSetting("specular", sectionStr);
			Ogre::String normal = terrainconfig->getSetting("normal", sectionStr);
			Ogre::String blend = terrainconfig->getSetting("blend", sectionStr);
		
			// add layer		
			imp.layerList[i].textureNames.push_back(specular);
			imp.layerList[i].textureNames.push_back(normal);	
			imp.layerList[i].worldSize = layerworldsize;

			blendmaps[i] = blend; 
		}
	}

void 
MaterialPreviewDialog::buildPreviewBitmap( const Ogre::String &texName )
{
	const Ogre::uchar BytePerPixel = 8;

	// 读取原始image
	Ogre::Image *oriImage = getPreviewImage(texName);
	// 源大纹理的大小
	size_t oriImageHeight = oriImage->getHeight();
	size_t oriImageWidth = oriImage->getWidth();

	Ogre::uchar *oriImageData = oriImage->getData();

	// 分配一个足够大的空间来保存新建的image的数据
	size_t newImagegetRowSpan = oriImageWidth*oriImage->getBPP()/BytePerPixel;  // 新建的image的行宽（单位为字节）
	Ogre::uchar *newImageData = OGRE_ALLOC_T(Ogre::uchar, oriImageHeight*newImagegetRowSpan, Ogre::MEMCATEGORY_GENERAL);//new Ogre::uchar[oriImageHeight*newImagegetRowSpan];

	Ogre::uchar *newImageDataPointer = newImageData;

	Ogre::uchar *oriImagedataPointer = oriImageData;

	// 把所选的纹理的数据提取出来，并创建一个新的image
	for ( Ogre::uint i=0; i<oriImageHeight; ++i )
	{
		memcpy(newImageDataPointer, oriImagedataPointer, newImagegetRowSpan);
		newImageDataPointer += newImagegetRowSpan;
		oriImagedataPointer += oriImage->getRowSpan();
	}

	Ogre::Image newImage;
	newImage.loadDynamicImage(newImageData,oriImageWidth,oriImageHeight,1,oriImage->getFormat(),true);

	// 如果所选纹理大于64*64，就先resize
	if ( oriImageWidth > mPreviewImageWidth || oriImageHeight > mPreviewImageHeight )
		newImage.resize(mPreviewImageWidth, mPreviewImageHeight);

	// 如果有alpha，要与黑白图进行混合
	if ( newImage.getHasAlpha() )
	{
		Ogre::ColourValue col;

		for ( int i=0; i<mPreviewImageWidth; ++i )
		{
			for ( int j=0; j<mPreviewImageWidth; ++j )
			{
				col = newImage.getColourAt(j,i,0);

				float alphaValue = col.a;

				unsigned char r = col.r*255 * alphaValue; 
				unsigned char g = col.g*255 * alphaValue; 
				unsigned char b = col.b*255 * alphaValue;

				// 设置到image中
				mCurrentPreviewImage.SetRGB(j,i,r,g,b);
			}
		}
	}
	// 没有alpha，就直接拷贝数据
	else
	{
		Ogre::ColourValue col;

		for ( int i=0; i<mPreviewImageWidth; ++i )
		{
			for ( int j=0; j<mPreviewImageWidth; ++j )
			{
				col = newImage.getColourAt(j,i,0);

				unsigned char r = col.r*255;
				unsigned char g = col.g*255;
				unsigned char b = col.b*255;

				// 设置到image中
				mCurrentPreviewImage.SetRGB(j,i,r,g,b);
			}
		}
	}
}

/* ----------------------------------------------------------------------- 
 | build bullet height field shape and generate ogre mesh from grayscale image
 | 
 | @param in : 
 | @param out: raw data of height field terrain
 | ToDo: adjest grid scale, grid height, local scale, max/min height
   ----------------------------------------------------------------------- */
bool
buildHeightFieldTerrainFromImage(const Ogre::String& filename, 
                                 btDynamicsWorld* dynamicsWorld, 
                                 btAlignedObjectArray<btCollisionShape*>& collisionShapes,
                                 void* &data)
{
    Ogre::Image img;
    try
    {
        img.load(filename, Ogre::ResourceGroupManager::DEFAULT_RESOURCE_GROUP_NAME);
    }   
    catch(Ogre::Exception err)
    {
        LOG(err.what());
        return false;
    }
    
    size_t grid_w = 65, grid_h = 65; // must be (2^N) + 1
    size_t grid_max_w = 129, grid_max_h = 129; // must be (2^N) + 1
    size_t img_w = img.getWidth();
    size_t img_h = img.getHeight();
    
    // validate image size is (2^N) + 1
    if ((img_w-1) & (img_w-2)) img_w = grid_w; 
    if ((img_h-1) & (img_h-2)) img_h = grid_h;
    //if (img_w > grid_max_w) img_w = grid_max_w; 
    //if (img_h > grid_max_h) img_h = grid_max_h; 

    LOG("LoadImage name=%s, width=%d, height=%d, width^2+1=%d, height^2+1=%d",
        filename.c_str(), img.getWidth(), img.getHeight(), img_w, img_h);
    img.resize(img_w, img_h);

    size_t pixelSize = Ogre::PixelUtil::getNumElemBytes(img.getFormat());    
    size_t bufSize = img.getSize() / pixelSize;
    data = new Ogre::Real[ bufSize ];
    Ogre::Real* dest = static_cast<Ogre::Real*>(data);
    memset(dest, 0, bufSize);
        
    /*
     | @ Notice the alignment problem
     | - uchar to float alignment
     | - pixel format in bytes as rawdata type, also affects alignment
     */
    Ogre::uchar* src = img.getData();    
    for (size_t i=0;i<bufSize;++i)
    {        
        dest[i] = ((Ogre::Real)src[i * pixelSize] - 127.0f)/16.0f;
    }
          
    // parameter    
    int upAxis = 1;
    btScalar gridSpacing = 5.0f;
    btScalar gridHeightScale = 0.2f;
    btScalar minHeight = -10.0f;
    btScalar maxHeight = 10.0f;
    btScalar defaultContactProcessingThreshold = BT_LARGE_FLOAT;

	btHeightfieldTerrainShape *heightfieldShape =  
        new btHeightfieldTerrainShape(img_w, img_h,
                                      dest,
                                      gridHeightScale,
                                      minHeight, maxHeight,
                                      upAxis, PHY_FLOAT, false);
	btAssert(heightfieldShape && "null heightfield");

	// shape
	btVector3 localScaling(1.0f, 1.0f, 1.0f);
	heightfieldShape->setLocalScaling(localScaling);    
    collisionShapes.push_back(heightfieldShape);

    // rigidBody
    btDefaultMotionState* motionState = new btDefaultMotionState(btTransform(btQuaternion(0,0,0,1),btVector3(0,0,0)));
    btRigidBody::btRigidBodyConstructionInfo cInfo(0, motionState, heightfieldShape, btVector3(0,0,0));
    btRigidBody* rigidBody = new btRigidBody(cInfo);        	
	rigidBody->setContactProcessingThreshold(defaultContactProcessingThreshold);
    int flags = rigidBody->getCollisionFlags();
    rigidBody->setCollisionFlags(flags | btCollisionObject::CF_DISABLE_VISUALIZE_OBJECT);
    
    dynamicsWorld->addRigidBody(rigidBody);
    
    // add ogre height field mesh
    Ogre::SceneManager* sceneMgr = Ogre::Root::getSingletonPtr()->getSceneManager("DefaultSceneManager");
    btAssert(sceneMgr);
    
    Ogre::ManualObject* obj = sceneMgr->createManualObject("btHeightFieldEntity");

    btVector3 aabbMin, aabbMax;
    heightfieldShape->getAabb(btTransform(btQuaternion(0,0,0,1),btVector3(0,0,0)), aabbMin, aabbMax);

    btHeightFieldProcessor callback(obj, "DefaultPlane");
    heightfieldShape->processAllTriangles(&callback, aabbMin, aabbMax);
   
    sceneMgr->getRootSceneNode()->attachObject(obj);
//.........这里部分代码省略.........