API加载earth文件的解析
转文章API加载earth文件的解析。最后一个问题下午解决。通过\src\osgEarthDrivers\earth\ReaderWriterOsgEarth.cpp文件
ReaderWriterEarth类,用来解析“earth”文件
在文件225行的readNode函数virtual ReadResult readNode(std::istream& in, const osgDB::Options* readOptions) const
{
// pull the URI context from the options structure (since we're reading
// from an "anonymous" stream here)
URIContext uriContext( readOptions );
osg::ref_ptr<XmlDocument> doc = XmlDocument::load( in, uriContext );
if ( !doc.valid() )
return ReadResult::ERROR_IN_READING_FILE;
Config docConf = doc->getConfig();
// support both "map" and "earth" tag names at the top level
Config conf;
if ( docConf.hasChild( "map" ) )
conf = docConf.child( "map" );
else if ( docConf.hasChild( "earth" ) )
conf = docConf.child( "earth" );
osg::ref_ptr<osg::Node> node;
if ( !conf.empty() )
{
// see if we were given a reference URI to use:
std::string refURI = uriContext.referrer();
if ( conf.value("version") == "1" )
{
OE_INFO << LC << "Detected a version 1.x earth file" << std::endl;
EarthFileSerializer1 ser;
node = ser.deserialize( conf, refURI );
}
else
{
if ( conf.value("version") != "2" )
OE_DEBUG << LC << "No valid earth file version; assuming version='2'" << std::endl;
// attempt to parse a "default options" JSON string:
std::string defaultConfStr;
if ( readOptions )
{
defaultConfStr = readOptions->getPluginStringData("osgEarth.defaultOptions");
if ( !defaultConfStr.empty() )
{
Config optionsConf("options");
if (optionsConf.fromJSON(defaultConfStr))
{
//OE_NOTICE << "\n\nOriginal = \n" << conf.toJSON(true) << "\n";
Config* original = conf.mutable_child("options");
if ( original )
{
recursiveUniqueKeyMerge(optionsConf, *original);
}
if ( !optionsConf.empty() )
{
conf.set("options", optionsConf);
}
//OE_NOTICE << "\n\nMerged = \n" << conf.toJSON(true) << "\n";
}
}
}
EarthFileSerializer2 ser;
node = ser.deserialize( conf, refURI );
}
}
MapNode* mapNode = MapNode::get(node.get());
if (mapNode)
{
// If the user passed in a cache object, apply it to the map now
CacheSettings* cacheSettings = CacheSettings::get(readOptions);
if (cacheSettings && cacheSettings->getCache())
{
mapNode->getMap()->setCache( cacheSettings->getCache() );
OE_INFO << LC << "Applied user-supplied cache to the Map\n";
}
}
return ReadResult(node.get());
}
};看到65行的读取调用
进入\src\osgEarthDrivers\earth\EarthFileSerializer2.cpp文件
EarthFileSerializer2类的deserialize函数
void addImageLayer(const Config& conf, Map* map)
{
ImageLayerOptions options( conf );
options.name() = conf.value("name");
ImageLayer* layer = new ImageLayer(options);
map->addLayer(layer);
if (layer->getStatus().isError())
OE_WARN << LC << "Layer \"" << layer->getName() << "\" : " << layer->getStatus().toString() << std::endl;
}
void addElevationLayer(const Config& conf, Map* map)
{
ElevationLayerOptions options( conf );
options.name() = conf.value( "name" );
ElevationLayer* layer = new ElevationLayer(options);
map->addLayer(layer);
if (layer->getStatus().isError())
OE_WARN << LC << "Layer \"" << layer->getName() << "\" : " << layer->getStatus().toString() << std::endl;
}
void addModelLayer(const Config& conf, Map* map)
{
ModelLayerOptions options( conf );
options.name() = conf.value( "name" );
options.driver() = ModelSourceOptions( conf );
ModelLayer* layer = new ModelLayer(options);
map->addLayer(layer);
if (layer->getStatus().isError())
OE_WARN << LC << "Layer \"" << layer->getName() << "\" : " << layer->getStatus().toString() << std::endl;
}
void addMaskLayer(const Config& conf, Map* map)
{
MaskLayerOptions options(conf);
options.name() = conf.value( "name" );
options.driver() = MaskSourceOptions(options);
MaskLayer* layer = new MaskLayer(options);
map->addLayer(layer);
if (layer->getStatus().isError())
OE_WARN << LC << "Layer \"" << layer->getName() << "\" : " << layer->getStatus().toString() << std::endl;
}
// support for "special" extension names (convenience and backwards compat)
Extension* createSpecialExtension(const Config& conf)
{
// special support for the default sky extension:
if (conf.key() == "sky" && !conf.hasValue("driver"))
return Extension::create("sky_simple", conf);
if (conf.key() == "ocean" && !conf.hasValue("driver"))
return Extension::create("ocean_simple", conf);
return 0L;
}
bool addLayer(const Config& conf, Map* map)
{
std::string name = conf.key();
Layer* layer = Layer::create(name, conf);
if (layer)
{
map->addLayer(layer);
if (layer->getStatus().isError())
OE_WARN << LC << "Layer \"" << layer->getName() << "\" : " << layer->getStatus().toString() << std::endl;
}
return layer != 0L;
}
osg::Node*
EarthFileSerializer2::deserialize( const Config& conf, const std::string& referrer ) const
{
// First, pre-load any extension DLLs.
preloadExtensionLibs(conf);
preloadExtensionLibs(conf.child("extensions"));
preloadExtensionLibs(conf.child("external"));
MapOptions mapOptions( conf.child( "options" ) );
// legacy: check for name/type in top-level attrs:
if ( conf.hasValue( "name" ) || conf.hasValue( "type" ) )
{
Config legacy;
if ( conf.hasValue("name") ) legacy.add( "name", conf.value("name") );
if ( conf.hasValue("type") ) legacy.add( "type", conf.value("type") );
mapOptions.mergeConfig( legacy );
}
Map* map = new Map( mapOptions );
// Start a batch update of the map:
map->beginUpdate();
// Read all the elevation layers in FIRST so other layers can access them for things like clamping.
for(ConfigSet::const_iterator i = conf.children().begin(); i != conf.children().end(); ++i)
{
if ( i->key() == "elevation" || i->key() == "heightfield" )
{
addElevationLayer( *i, map );
}
}
Config externalConfig;
std::vector<osg::ref_ptr<Extension> > extensions;
// Read the layers in LAST (otherwise they will not benefit from the cache/profile configuration)
for(ConfigSet::const_iterator i = conf.children().begin(); i != conf.children().end(); ++i)
{
if (i->key() == "options" || i->key() == "name" || i->key() == "type" || i->key() == "version")
{
// nop - handled earlier
}
else if ( i->key() == "image" )
{
addImageLayer( *i, map );
}
else if ( i->key() == "model" )
{
addModelLayer( *i, map );
}
else if ( i->key() == "mask" )
{
addMaskLayer( *i, map );
}
else if ( i->key() == "external" || i->key() == "extensions" )
{
externalConfig = *i;
for(ConfigSet::const_iterator e = i->children().begin(); e != i->children().end(); ++e)
{
Extension* extension = loadExtension(*e);
if (extension)
extensions.push_back(extension);
//addExtension( *e, mapNode.get() );
}
}
else if ( !isReservedWord(i->key()) ) // plugins/extensions.
{
bool addedLayer = addLayer(*i, map); //mapNode.get());
if ( !addedLayer )
{
Extension* extension = loadExtension(*i);
if (extension)
extensions.push_back(extension);
//OE_INFO << LC << "Tried to load \"" << i->key() << "\" as a layer; now trying extension\n";
//addExtension( *i, mapNode.get() );
}
}
}
// Complete the batch update of the map
map->endUpdate();
// Yes, MapOptions and MapNodeOptions share the same Config node. Weird but true.
MapNodeOptions mapNodeOptions( conf.child("options") );
// Create a map node.
osg::ref_ptr<MapNode> mapNode = new MapNode( map, mapNodeOptions );
// Apply the external conf if there is one.
if (!externalConfig.empty())
{
mapNode->externalConfig() = externalConfig;
}
// Install the extensions
for (unsigned i = 0; i < extensions.size(); ++i)
{
mapNode->addExtension(extensions.at(i).get());
}
// return the topmost parent of the mapnode. It's possible that
// an extension added parents!
osg::Node* top = mapNode.release();
while( top->getNumParents() > 0 )
top = top->getParent(0);
return top;
}
从上面可以看到
1 earth插件 map 统筹OE中所有"层"的概念,支持多层影像,高程,模型,镂空层(mask)等
2各个层相应配置的属性由指定的Option类从Config中获取,如果对应Config中有Option类指定元素相应值的配置Option将其写入
为了统筹OE各个层的属性配置,OE提供了ConfigOptions类,ConfigOptions类就是对某个Config类的封装,提供了到Config层次上的调用,例如Config赋值,拼接等
为不同层的属性配置提供了存储载体,结合上文map包含的图层有以下关系
通过这些类,可以很方便的将特定的XML节点下属性配置生成Config归类到某一个图层中,以下列出部分图层的属性(仅供参考)
MapOptions:XML<<options>>节点下配置的信息,主要是配置地形渲染时的属性;包括如下
<elevation_interploation> 插值,nearset 最近点插值average 最近点平均值 bilinear 线性插值,triangulate 三角面片插值
<elevation_tile_size> 瓦片大小
<elevation_texture_size> 纹理大小
<overlay_wapring> 纹理装载
<overlay_blending>混合
<overlay_minmapping>纹理映射
<overlay_texture_size>
<overlay_attach_stencil>模板
ImageLayerOptions: XML<<image>>节点下配置的信息,很明显,影像属性配置,部分属性值
<nodata_image> 无数据显示的url
<opacity> 透明度
<min_range> 最小可视范围
<max_range> 最大可视范围
<min_level>最小显示细节层级
<max_level>最大显示细节层级
<min_resolution> 数据的最小分辨率,单位的像素
<max_resolution>数据的最大分辨率,单位的像素
<enable> 是否包含进map层
<visible> 可视
ElevationLayerOptions: XML<<elevation>>or<<heightfield>>节点下配置的信息,高程层
<min_level>最小显示细节层级
<max_level>最大显示细节层级
<min_resolution> 数据的最小分辨率,单位的像素
<max_resolution>数据的最大分辨率,单位的像素
<enable> 是否包含进map层
ModelLayerOptions: XML<<Model>>节点下配置的信息 模型层装载 矢量数据,模型,几何体等
<name>
<driver>
<enable><span style="font-family:Arial, Helvetica, sans-serif;">是否包含进map层</span>
<visible>是否可见
<overLay>
MaskLayerOptions: XML<<mask>>节点配置下的信息,镂空层
一个比较特殊的节点 ext(Config); 暂且叫他功能层,XML <<external>>,它由mapNode直接读取配置信息,实现一些经常用到的功能点,例如 视点定位 <<<viewpoint>> 星空时刻设置<<sky>>
最后的masklayer
<mask driver="feature" name="mask">
<features driver="ogr">
<geometry>
POLYGON(( -111.0466 42.0015 0, -111.0467 40.9979 0, -109.0501 41.0007 0, -109.0452 36.9991 0, -114.0506 37.0004 0, -114.0417 41.9937 0))
</geometry>
</features>
<profile>global-geodetic</profile>
</mask>
api开发的方式 char *driver = Tcl_GetString(objv);
2001 char *format = Tcl_GetString(objv);
2002 if (format && strlen(format) > 0 &&
2003 strcmp(format, "json") != 0 && strcmp(format, "gml") != 0) {
2004 Tcl_AppendResult(interp, "unknown format \"", format,
2005 "\": should be 'json' or 'gml'", (char*)NULL);
2006 return TCL_ERROR;
2007 }
2008 char *typeName = Tcl_GetString(objv);
2009 osgEarth::Drivers::FeatureMaskOptions maskOpts;
2010 std::string url;
2011 if (objc > 8) {
2012 if (driver == 'w' && strcmp(driver, "wkt") == 0) {
2013 url = Tcl_GetString(objv);
2014 if (url.empty()) {
2015 Tcl_AppendResult(interp, "Empty WKT length",
2016 (char*)NULL);
2017 return TCL_ERROR;
2018 }
2019 } else {
2020 char *urlIn = Tcl_GetString(objv);
2021 url = g_renderer->getCanonicalPath(std::string(urlIn));
2022 if (url.empty()) {
2023 Tcl_AppendResult(interp, "file not found: \"",
2024 urlIn, "\"", (char*)NULL);
2025 return TCL_ERROR;
2026 }
2027 }
2028 }
2029 if (driver == 'd' && strcmp(driver, "db") == 0) {
2030 osgEarth::Drivers::OGRFeatureOptions opts;
2031 opts.name() = name;
2032 opts.connection() = url;
2033 opts.layer() = typeName;
2034 maskOpts.featureOptions() = opts;
2035 } else if (driver == 'o' && strcmp(driver, "ogr") == 0) {
2036 osgEarth::Drivers::OGRFeatureOptions opts;
2037 opts.name() = name;
2038 opts.url() = url;
2039 maskOpts.featureOptions() = opts;
2040 } else if (driver == 't' && strcmp(driver, "tfs") == 0) {
2041 osgEarth::Drivers::TFSFeatureOptions opts;
2042 opts.name() = name;
2043 opts.url() = url;
2044 opts.format() = format;
2045 maskOpts.featureOptions() = opts;
2046 } else if (driver == 'w' && strcmp(driver, "wfs") == 0) {
2047 osgEarth::Drivers::WFSFeatureOptions opts;
2048 opts.name() = name;
2049 opts.url() = url;
2050 opts.outputFormat() = format;
2051 opts.typeName() = typeName;
2052 maskOpts.featureOptions() = opts;
2053 } else if (driver == 'w' && strcmp(driver, "wkt") == 0) {
2054 // Inline geometry, url is length of following data
2055 char *ptr;
2056 long len = strtol(url.c_str(), &ptr, 10);
2057 if (len <= 0 || *ptr != '\0') {
2058 Tcl_AppendResult(interp, "Failed to parse WKT length: \"",
2059 url.c_str(), "\"", (char*)NULL);
2060 return TCL_ERROR;
2061 }
2062 char *wkt = (char *)malloc((size_t)len);
2063 if (!SocketRead(wkt, len)) {
2064 free(wkt);
2065 Tcl_AppendResult(interp, "Failed to read WKT string",
2066 (char*)NULL);
2067 return TCL_ERROR;
2068 }
2069 osgEarth::Drivers::OGRFeatureOptions opts;
2070 opts.name() = name;
2071 TRACE("Geometry: \"%s\"", wkt);
2072 osgEarth::Config conf("geometry", std::string(wkt));
2073 free(wkt);
2074 opts.geometryConfig() = conf;
2075 maskOpts.featureOptions() = opts;
2076 } else if (driver == 'w' && strcmp(driver, "wkt_file") == 0) {
2077 osgEarth::Drivers::OGRFeatureOptions opts;
2078 opts.name() = name;
2079 opts.geometryUrl() = url;
2080 maskOpts.featureOptions() = opts;
2081 } else {
2082 Tcl_AppendResult(interp, "unknown mask driver \"", driver,
2083 "\": should be 'db', 'ogr', 'tfs', 'wfs', 'wkt', or 'wkt_file'", (char*)NULL);
2084 return TCL_ERROR;
2085 }
2086 int minLOD = 0;
2087 if (objc > 9) {
2088 if (Tcl_GetIntFromObj(interp, objv, &minLOD) != TCL_OK) {
2089 return TCL_ERROR;
2090 }
2091 }
2092 g_renderer->addTerrainMaskLayer(name, maskOpts, (unsigned)minLOD); 本帖最后由 liyihongcug 于 2020-3-11 16:18 编辑
例如
<options type="geocentric">
<cache path="d:/test/cache_dir" type="filesystem" />
<terrain first_lod="0" tile_size="17" />
</options>
<options>
<lighting>false</lighting>
<overlay_blending>false</overlay_blending>
<terrain min_lod="8"/>
</options>
MapOptions( const ConfigOptions& options =ConfigOptions() )
: ConfigOptions ( options ),
_cachePolicy ( ),
_cstype ( CSTYPE_GEOCENTRIC ),
_referenceURI ( "" ),
_elevationInterpolation( INTERP_BILINEAR )
MapOptions MapOptions.cpp
optional<std::string> _name;
optional<ProfileOptions> _profileOptions;
optional<CacheOptions> _cacheOptions;
optional<CachePolicy> _cachePolicy;
optional<CoordinateSystemType> _cstype;
optional<std::string> _referenceURI;
optional<ElevationInterpolation> _elevationInterpolation;
terrain的源文件在TerrainOptions.cpp
MapOptions:XML<<options>>节点下配置的信息,主要是配置地形渲染时的属性;包括如下
<elevation_interploation> 插值,nearset 最近点插值average 最近点平均值 bilinear 线性插值,triangulate 三角面片插值
<elevation_tile_size> 瓦片大小
<elevation_texture_size> 纹理大小
<overlay_wapring> 纹理装载
<overlay_blending>混合
<overlay_minmapping>纹理映射
<overlay_texture_size>
<overlay_attach_stencil>模板 2.8里没有这些参数,2.10才有
TerrainOptions::getConfig() const
{
Config conf = DriverConfigOptions::getConfig();
conf.key() = "terrain";
conf.updateIfSet( "tile_size", _tileSize );
conf.updateIfSet( "vertical_scale", _verticalScale );
conf.updateIfSet( "vertical_offset", _verticalOffset );
conf.updateIfSet( "min_tile_range_factor", _minTileRangeFactor );
conf.updateIfSet( "range_factor", _minTileRangeFactor );
conf.updateIfSet( "max_lod", _maxLOD );
conf.updateIfSet( "min_lod", _minLOD );
conf.updateIfSet( "first_lod", _firstLOD );
conf.updateIfSet( "lighting", _enableLighting );
conf.updateIfSet( "attenuation_distance", _attenuationDistance );
conf.updateIfSet( "lod_transition_time", _lodTransitionTimeSeconds );
conf.updateIfSet( "mipmapping", _enableMipmapping );
conf.updateIfSet( "cluster_culling", _clusterCulling );
conf.updateIfSet( "blending", _enableBlending );
conf.updateIfSet( "mercator_fast_path", _mercatorFastPath );
conf.updateIfSet( "min_normal_map_lod", _minNormalMapLOD );
conf.updateIfSet( "gpu_tessellation", _gpuTessellation );
conf.updateIfSet( "debug", _debug );
conf.updateIfSet( "bin_number", _binNumber );
conf.updateIfSet( "min_expiry_time", _minExpiryTime);
conf.updateIfSet( "min_expiry_frames", _minExpiryFrames);
//Save the filter settings
conf.updateIfSet("mag_filter","LINEAR", _magFilter,osg::Texture::LINEAR);
conf.updateIfSet("mag_filter","LINEAR_MIPMAP_LINEAR",_magFilter,osg::Texture::LINEAR_MIPMAP_LINEAR);
conf.updateIfSet("mag_filter","LINEAR_MIPMAP_NEAREST", _magFilter,osg::Texture::LINEAR_MIPMAP_NEAREST);
conf.updateIfSet("mag_filter","NEAREST", _magFilter,osg::Texture::NEAREST);
conf.updateIfSet("mag_filter","NEAREST_MIPMAP_LINEAR", _magFilter,osg::Texture::NEAREST_MIPMAP_LINEAR);
conf.updateIfSet("mag_filter","NEAREST_MIPMAP_NEAREST",_magFilter,osg::Texture::NEAREST_MIPMAP_NEAREST);
conf.updateIfSet("min_filter","LINEAR", _minFilter,osg::Texture::LINEAR);
conf.updateIfSet("min_filter","LINEAR_MIPMAP_LINEAR",_minFilter,osg::Texture::LINEAR_MIPMAP_LINEAR);
conf.updateIfSet("min_filter","LINEAR_MIPMAP_NEAREST", _minFilter,osg::Texture::LINEAR_MIPMAP_NEAREST);
conf.updateIfSet("min_filter","NEAREST", _minFilter,osg::Texture::NEAREST);
conf.updateIfSet("min_filter","NEAREST_MIPMAP_LINEAR", _minFilter,osg::Texture::NEAREST_MIPMAP_LINEAR);
conf.updateIfSet("min_filter","NEAREST_MIPMAP_NEAREST",_minFilter,osg::Texture::NEAREST_MIPMAP_NEAREST);
return conf;
}
页:
[1]