osg::Node* BuildTextOperator::operator()(const FeatureList& features,
const TextSymbol* symbol,
const FilterContext& context)
{
if (!symbol) return 0;
std::set< std::string > labelNames;
bool removeDuplicateLabels = symbol->removeDuplicateLabels().isSet() ? symbol->removeDuplicateLabels().get() : false;
osg::Geode* result = new osg::Geode;
for (FeatureList::const_iterator itr = features.begin(); itr != features.end(); ++itr)
{
Feature* feature = itr->get();
if (!feature->getGeometry()) continue;
std::string text;
//If the feature is a TextAnnotation, just get the value from it
TextAnnotation* annotation = dynamic_cast<TextAnnotation*>(feature);
if (annotation)
{
text = annotation->text();
}
else if (symbol->content().isSet())
{
//Get the text from the specified content and referenced attributes
std::string content = symbol->content().value();
text = parseAttributes(feature, content, symbol->contentAttributeDelimiter().value());
}
else if (symbol->attribute().isSet())
{
//Get the text from the specified attribute
std::string attr = symbol->attribute().value();
text = feature->getAttr(attr);
}
if (text.empty()) continue;
//See if there is a duplicate name
if (removeDuplicateLabels && labelNames.find(text) != labelNames.end()) continue;
bool rotateToScreen = symbol->rotateToScreen().isSet() ? symbol->rotateToScreen().value() : false;
// find the centroid
osg::Vec3d position;
osg::Quat orientation;
GeometryIterator gi( feature->getGeometry() );
while( gi.hasMore() )
{
Geometry* geom = gi.next();
TextSymbol::LinePlacement linePlacement = symbol->linePlacement().isSet() ? symbol->linePlacement().get() : TextSymbol::LINEPLACEMENT_ALONG_LINE;
if (geom->getType() == Symbology::Geometry::TYPE_LINESTRING && linePlacement == TextSymbol::LINEPLACEMENT_ALONG_LINE)
{
//Compute the "middle" of the line string
LineString* lineString = static_cast<LineString*>(geom);
double length = lineString->getLength();
double center = length / 2.0;
osg::Vec3d start, end;
if (lineString->getSegment(center, start, end))
{
TextSymbol::LineOrientation lineOrientation = symbol->lineOrientation().isSet() ? symbol->lineOrientation().get() : TextSymbol::LINEORIENTATION_HORIZONTAL;
position = (end + start) / 2.0;
//We don't want to orient the text at all if we are rotating to the screen
if (!rotateToScreen && lineOrientation != TextSymbol::LINEORIENTATION_HORIZONTAL)
{
osg::Vec3d dir = (end-start);
dir.normalize();
if (lineOrientation == TextSymbol::LINEORIENTATION_PERPENDICULAR)
{
osg::Vec3d up(0,0,1);
const SpatialReference* srs = context.profile()->getSRS();
if (srs && context.isGeocentric() && srs->getEllipsoid())
{
osg::Vec3d w = context.toWorld( position );
up = srs->getEllipsoid()->computeLocalUpVector(w.x(), w.y(), w.z());
}
dir = up ^ dir;
}
orientation.makeRotate(osg::Vec3d(1,0,0), dir);
}
}
else
{
//Fall back on using the center
position = lineString->getBounds().center();
}
}
else
{
position = geom->getBounds().center();
}
}
osgText::Text* t = new osgText::Text();
t->setText( text );
std::string font = "fonts/arial.ttf";
if (symbol->font().isSet() && !symbol->font().get().empty())
{
font = symbol->font().value();
}
t->setFont( font );
t->setAutoRotateToScreen( rotateToScreen );
TextSymbol::SizeMode sizeMode = symbol->sizeMode().isSet() ? symbol->sizeMode().get() : TextSymbol::SIZEMODE_SCREEN;
if (sizeMode == TextSymbol::SIZEMODE_SCREEN) {
t->setCharacterSizeMode( osgText::TextBase::SCREEN_COORDS );
}
else if (sizeMode == TextSymbol::SIZEMODE_OBJECT) {
t->setCharacterSizeMode( osgText::TextBase::OBJECT_COORDS );
}
float size = symbol->size().isSet() ? symbol->size().get() : 32.0f;
t->setCharacterSize( size );
//t->setCharacterSizeMode( osgText::TextBase::OBJECT_COORDS_WITH_MAXIMUM_SCREEN_SIZE_CAPPED_BY_FONT_HEIGHT );
//t->setCharacterSize( 300000.0f );
t->setPosition( position );
t->setRotation( orientation);
t->setAlignment( osgText::TextBase::CENTER_CENTER );
t->getOrCreateStateSet()->setAttributeAndModes( new osg::Depth(osg::Depth::ALWAYS), osg::StateAttribute::ON );
t->getOrCreateStateSet()->setRenderBinDetails( 99999, "RenderBin" );
// apply styling as appropriate:
osg::Vec4f textColor = symbol->fill()->color();
osg::Vec4f haloColor = symbol->halo()->color();
t->setColor( textColor );
t->setBackdropColor( haloColor );
t->setBackdropType( osgText::Text::OUTLINE );
if ( context.isGeocentric() )
{
// install a cluster culler
t->setCullCallback( new CullPlaneCallback( position * context.inverseReferenceFrame() ) );
}
result->addDrawable( t );
if (removeDuplicateLabels) labelNames.insert(text);
}
return result;
}
