/**
* Stats the given file. If <tt>throttleRate</tt> seconds have passed since
* the last time stat() was called on this file, then the file will be
* re-stat()ted, otherwise the cached stat information will be returned.
*
* @param filename The file to stat.
* @param stat A pointer to a stat struct; the retrieved stat information
* will be stored here.
* @param throttleRate Tells this CachedFileStat that the file may only
* be statted at most every <tt>throttleRate</tt> seconds.
* @return 0 if the stat() call succeeded or if the cached stat information was used;
* -1 if something went wrong while statting the file. In the latter
* case, <tt>errno</tt> will be populated with an appropriate error code.
* @throws SystemException Something went wrong while retrieving the
* system time. stat() errors will <em>not</em> result in
* SystemException being thrown.
* @throws boost::thread_interrupted
*/
int stat(const string &filename, struct stat *buf, unsigned int throttleRate = 0) {
boost::unique_lock<boost::mutex> l(lock);
EntryMap::iterator it(cache.find(filename));
EntryPtr entry;
int ret;
if (it == cache.end()) {
// Filename not in cache.
// If cache is full, remove the least recently used
// cache entry.
if (maxSize != 0 && cache.size() == maxSize) {
EntryList::iterator listEnd(entries.end());
listEnd--;
string filename((*listEnd)->filename);
entries.pop_back();
cache.erase(filename);
}
// Add to cache as most recently used.
entry = EntryPtr(new Entry(filename));
entries.push_front(entry);
cache[filename] = entries.begin();
} else {
// Cache hit.
entry = *it->second;
// Mark this cache item as most recently used.
entries.erase(it->second);
entries.push_front(entry);
cache[filename] = entries.begin();
}
ret = entry->refresh(throttleRate);
*buf = entry->info;
return ret;
}
/**
* Creates a complete set of positioned label nodes from a feature list.
*/
osg::Node* createNode(
const FeatureList& input,
const Style& style,
const FilterContext& context )
{
const TextSymbol* text = style.get<TextSymbol>();
if ( !text )
return 0L;
osg::Group* group = new osg::Group();
Decluttering::setEnabled( group->getOrCreateStateSet(), true );
if ( text->priority().isSet() )
{
DeclutteringOptions dco = Decluttering::getOptions();
dco.sortByPriority() = text->priority().isSet();
Decluttering::setOptions( dco );
}
StringExpression contentExpr ( *text->content() );
NumericExpression priorityExpr( *text->priority() );
if ( text->removeDuplicateLabels() == true )
{
// in remove-duplicates mode, make a list of unique features, selecting
// the one with the largest area as the one we'll use for labeling.
typedef std::pair<double, osg::ref_ptr<const Feature> > Entry;
typedef std::map<std::string, Entry> EntryMap;
EntryMap used;
for( FeatureList::const_iterator i = input.begin(); i != input.end(); ++i )
{
Feature* feature = i->get();
if ( feature && feature->getGeometry() )
{
const std::string& value = feature->eval( contentExpr );
if ( !value.empty() )
{
double area = feature->getGeometry()->getBounds().area2d();
if ( used.find(value) == used.end() )
{
used[value] = Entry(area, feature);
}
else
{
Entry& biggest = used[value];
if ( area > biggest.first )
{
biggest.first = area;
biggest.second = feature;
}
}
}
}
}
for( EntryMap::iterator i = used.begin(); i != used.end(); ++i )
{
const std::string& value = i->first;
const Feature* feature = i->second.second.get();
group->addChild( makeLabelNode(context, feature, value, text, priorityExpr) );
}
}
else
{
for( FeatureList::const_iterator i = input.begin(); i != input.end(); ++i )
{
const Feature* feature = i->get();
if ( !feature )
continue;
const Geometry* geom = feature->getGeometry();
if ( !geom )
continue;
const std::string& value = feature->eval( contentExpr, &context );
if ( value.empty() )
continue;
group->addChild( makeLabelNode(context, feature, value, text, priorityExpr) );
}
}
#if 0 // good idea but needs work.
DepthOffsetGroup* dog = new DepthOffsetGroup();
dog->setMinimumOffset( 500.0 );
dog->addChild( group );
return dog;
#endif
return group;
}
/**
* Returns whether <tt>filename</tt> is in the cache.
*/
bool knows(const string &filename) const {
boost::unique_lock<boost::mutex> l(lock);
return cache.find(filename) != cache.end();
}
