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C++ TileSource::hasDataForFallback方法代码示例

本文整理汇总了C++中TileSource::hasDataForFallback方法的典型用法代码示例。如果您正苦于以下问题:C++ TileSource::hasDataForFallback方法的具体用法?C++ TileSource::hasDataForFallback怎么用?C++ TileSource::hasDataForFallback使用的例子?那么恭喜您, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在TileSource的用法示例。


在下文中一共展示了TileSource::hasDataForFallback方法的1个代码示例,这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞,您的评价将有助于系统推荐出更棒的C++代码示例。

示例1: assembleImageFromTileSource

GeoImage
ImageLayer::createImageFromTileSource(const TileKey&    key,
                                      ProgressCallback* progress,
                                      bool              forceFallback,
                                      bool&             out_isFallback)
{
    // Results:
    // 
    // * return an osg::Image matching the key extent is all goes well;
    //
    // * return NULL to indicate that the key exceeds the maximum LOD of the source data,
    //   and that the engine may need to generate a "fallback" tile if necessary;
    //
    // deprecated:
    // * return an "empty image" if the LOD is valid BUT the key does not intersect the
    //   source's data extents.

    out_isFallback = false;

    TileSource* source = getTileSource();
    if ( !source )
        return GeoImage::INVALID;

    // If the profiles are different, use a compositing method to assemble the tile.
    if ( !key.getProfile()->isEquivalentTo( getProfile() ) )
    {
        return assembleImageFromTileSource( key, progress, out_isFallback );
    }

    // Good to go, ask the tile source for an image:
    osg::ref_ptr<TileSource::ImageOperation> op = _preCacheOp;

    osg::ref_ptr<osg::Image> result;

    if ( forceFallback )
    {
        // check if the tile source has any data coverage for the requested key.
        // the LOD is ignore here and checked later
        if ( !source->hasDataInExtent( key.getExtent() ) )
        {
            OE_DEBUG << LC << "createImageFromTileSource: hasDataInExtent(" << key.str() << ") == false" << std::endl;
            return GeoImage::INVALID;
        }

        TileKey finalKey = key;
        while( !result.valid() && finalKey.valid() )
        {
            if ( !source->getBlacklist()->contains( finalKey.getTileId() ) &&
                source->hasDataForFallback(finalKey))
            {
                result = source->createImage( finalKey, op.get(), progress );
                if ( result.valid() )
                {
                    if ( finalKey.getLevelOfDetail() != key.getLevelOfDetail() )
                    {
                        // crop the fallback image to match the input key, and ensure that it remains the
                        // same pixel size; because chances are if we're requesting a fallback that we're
                        // planning to mosaic it later, and the mosaicer requires same-size images.
                        GeoImage raw( result.get(), finalKey.getExtent() );
                        GeoImage cropped = raw.crop( key.getExtent(), true, raw.getImage()->s(), raw.getImage()->t(), *_runtimeOptions.driver()->bilinearReprojection() );
                        result = cropped.takeImage();
                    }
                }
            }
            if ( !result.valid() )
            {
                finalKey = finalKey.createParentKey();
                out_isFallback = true;
            }
        }

        if ( !result.valid() )
        {
            result = 0L;
            //result = _emptyImage.get();
            finalKey = key;
        }
    }
    else
    {
        // Fail is the image is blacklisted.
        if ( source->getBlacklist()->contains( key.getTileId() ) )
        {
            OE_DEBUG << LC << "createImageFromTileSource: blacklisted(" << key.str() << ")" << std::endl;
            return GeoImage::INVALID;
        }
    
        if ( !source->hasData( key ) )
        {
            OE_DEBUG << LC << "createImageFromTileSource: hasData(" << key.str() << ") == false" << std::endl;
            return GeoImage::INVALID;
        }
        result = source->createImage( key, op.get(), progress );
    }

    // Process images with full alpha to properly support MP blending.    
    if ( result != 0L && *_runtimeOptions.featherPixels())
    {
        ImageUtils::featherAlphaRegions( result.get() );
    }    
//.........这里部分代码省略.........
开发者ID:APerennec,项目名称:osgearth,代码行数:101,代码来源:ImageLayer.cpp


注:本文中的TileSource::hasDataForFallback方法示例由纯净天空整理自Github/MSDocs等开源代码及文档管理平台,相关代码片段筛选自各路编程大神贡献的开源项目,源码版权归原作者所有,传播和使用请参考对应项目的License;未经允许,请勿转载。