FilterContext
ClampFilter::push( FeatureList& features, const FilterContext& cx )
{
const Session* session = cx.getSession();
if ( !session ) {
OE_WARN << LC << "No session - session is required for elevation clamping" << std::endl;
return cx;
}
// the map against which we'll be doing elevation clamping
MapFrame mapf = session->createMapFrame( Map::ELEVATION_LAYERS );
const SpatialReference* mapSRS = mapf.getProfile()->getSRS();
const SpatialReference* featureSRS = cx.profile()->getSRS();
bool isGeocentric = session->getMapInfo().isGeocentric();
// establish an elevation query interface based on the features' SRS.
ElevationQuery eq( mapf );
for( FeatureList::iterator i = features.begin(); i != features.end(); ++i )
{
Feature* feature = i->get();
GeometryIterator gi( feature->getGeometry() );
while( gi.hasMore() )
{
Geometry* geom = gi.next();
if ( isGeocentric )
{
// convert to map coords:
cx.toWorld( geom );
mapSRS->transformFromECEF( geom );
// populate the elevations:
eq.getElevations( geom, mapSRS );
// convert back to geocentric:
mapSRS->transformToECEF( geom );
cx.toLocal( geom );
}
else
{
// clamps the entire array to the highest available resolution.
eq.getElevations( geom, featureSRS );
}
}
}
return cx;
}
void
AltitudeFilter::pushAndClamp( FeatureList& features, FilterContext& cx )
{
const Session* session = cx.getSession();
// the map against which we'll be doing elevation clamping
//MapFrame mapf = session->createMapFrame( Map::ELEVATION_LAYERS );
MapFrame mapf = session->createMapFrame(
(Map::ModelParts)(Map::TERRAIN_LAYERS | Map::MODEL_LAYERS) );
const SpatialReference* mapSRS = mapf.getProfile()->getSRS();
osg::ref_ptr<const SpatialReference> featureSRS = cx.profile()->getSRS();
// establish an elevation query interface based on the features' SRS.
ElevationQuery eq( mapf );
// want a result even if it's low res
eq.setFallBackOnNoData( true );
NumericExpression scaleExpr;
if ( _altitude->verticalScale().isSet() )
scaleExpr = *_altitude->verticalScale();
NumericExpression offsetExpr;
if ( _altitude->verticalOffset().isSet() )
offsetExpr = *_altitude->verticalOffset();
// whether to record the min/max height-above-terrain values.
bool collectHATs =
_altitude->clamping() == AltitudeSymbol::CLAMP_RELATIVE_TO_TERRAIN ||
_altitude->clamping() == AltitudeSymbol::CLAMP_ABSOLUTE;
// whether to clamp every vertex (or just the centroid)
bool perVertex =
_altitude->binding() == AltitudeSymbol::BINDING_VERTEX;
// whether the SRS's have a compatible vertical datum.
bool vertEquiv =
featureSRS->isVertEquivalentTo( mapSRS );
for( FeatureList::iterator i = features.begin(); i != features.end(); ++i )
{
Feature* feature = i->get();
// run a symbol script if present.
if ( _altitude.valid() && _altitude->script().isSet() )
{
StringExpression temp( _altitude->script().get() );
feature->eval( temp, &cx );
}
double maxTerrainZ = -DBL_MAX;
double minTerrainZ = DBL_MAX;
double minHAT = DBL_MAX;
double maxHAT = -DBL_MAX;
double scaleZ = 1.0;
if ( _altitude.valid() && _altitude->verticalScale().isSet() )
scaleZ = feature->eval( scaleExpr, &cx );
double offsetZ = 0.0;
if ( _altitude.valid() && _altitude->verticalOffset().isSet() )
offsetZ = feature->eval( offsetExpr, &cx );
GeometryIterator gi( feature->getGeometry() );
while( gi.hasMore() )
{
Geometry* geom = gi.next();
// Absolute heights in Z. Only need to collect the HATs; the geometry
// remains unchanged.
if ( _altitude->clamping() == AltitudeSymbol::CLAMP_ABSOLUTE )
{
if ( perVertex )
{
std::vector<double> elevations;
elevations.reserve( geom->size() );
if ( eq.getElevations( geom->asVector(), featureSRS, elevations, _maxRes ) )
{
for( unsigned i=0; i<geom->size(); ++i )
{
osg::Vec3d& p = (*geom)[i];
p.z() *= scaleZ;
p.z() += offsetZ;
double z = p.z();
if ( !vertEquiv )
{
osg::Vec3d tempgeo;
if ( !featureSRS->transform(p, mapSRS->getGeographicSRS(), tempgeo) )
z = tempgeo.z();
}
double hat = z - elevations[i];
if ( hat > maxHAT )
maxHAT = hat;
if ( hat < minHAT )
minHAT = hat;
if ( elevations[i] > maxTerrainZ )
maxTerrainZ = elevations[i];
if ( elevations[i] < minTerrainZ )
minTerrainZ = elevations[i];
}
}
}
else // per centroid
{
osgEarth::Bounds bounds = geom->getBounds();
const osg::Vec2d& center = bounds.center2d();
GeoPoint centroid(featureSRS, center.x(), center.y());
double centroidElevation;
if ( eq.getElevation( centroid, centroidElevation, _maxRes ) )
{
for( unsigned i=0; i<geom->size(); ++i )
{
osg::Vec3d& p = (*geom)[i];
p.z() *= scaleZ;
p.z() += offsetZ;
double z = p.z();
if ( !vertEquiv )
{
osg::Vec3d tempgeo;
if ( !featureSRS->transform(p, mapSRS->getGeographicSRS(), tempgeo) )
z = tempgeo.z();
}
double hat = z - centroidElevation;
if ( hat > maxHAT )
maxHAT = hat;
if ( hat < minHAT )
minHAT = hat;
}
if ( centroidElevation > maxTerrainZ )
maxTerrainZ = centroidElevation;
if ( centroidElevation < minTerrainZ )
minTerrainZ = centroidElevation;
}
}
}
// Heights-above-ground in Z. Need to resolve this to an absolute number
// and record HATs along the way.
else if ( _altitude->clamping() == AltitudeSymbol::CLAMP_RELATIVE_TO_TERRAIN )
{
osg::ref_ptr<const SpatialReference> featureSRSwithMapVertDatum = !vertEquiv ?
SpatialReference::create(featureSRS->getHorizInitString(), mapSRS->getVertInitString()) : 0L;
if ( perVertex )
{
std::vector<double> elevations;
elevations.reserve( geom->size() );
if ( eq.getElevations( geom->asVector(), featureSRS, elevations, _maxRes ) )
{
for( unsigned i=0; i<geom->size(); ++i )
{
osg::Vec3d& p = (*geom)[i];
p.z() *= scaleZ;
p.z() += offsetZ;
double hat = p.z();
p.z() = elevations[i] + p.z();
// if necessary, convert the Z value (which is now in the map's SRS) back to
// the feature's SRS.
if ( !vertEquiv )
{
featureSRSwithMapVertDatum->transform(p, featureSRS, p);
}
if ( hat > maxHAT )
maxHAT = hat;
if ( hat < minHAT )
minHAT = hat;
if ( elevations[i] > maxTerrainZ )
maxTerrainZ = elevations[i];
if ( elevations[i] < minTerrainZ )
minTerrainZ = elevations[i];
}
}
}
else // per-centroid
{
osgEarth::Bounds bounds = geom->getBounds();
const osg::Vec2d& center = bounds.center2d();
GeoPoint centroid(featureSRS, center.x(), center.y());
double centroidElevation;
if ( eq.getElevation( centroid, centroidElevation, _maxRes ) )
{
for( unsigned i=0; i<geom->size(); ++i )
{
osg::Vec3d& p = (*geom)[i];
p.z() *= scaleZ;
p.z() += offsetZ;
double hat = p.z();
p.z() = centroidElevation + p.z();
// if necessary, convert the Z value (which is now in the map's SRS) back to
// the feature's SRS.
if ( !vertEquiv )
{
featureSRSwithMapVertDatum->transform(p, featureSRS, p);
}
if ( hat > maxHAT )
maxHAT = hat;
if ( hat < minHAT )
minHAT = hat;
}
if ( centroidElevation > maxTerrainZ )
maxTerrainZ = centroidElevation;
if ( centroidElevation < minTerrainZ )
minTerrainZ = centroidElevation;
}
}
}
// Clamp - replace the geometry's Z with the terrain height.
else // CLAMP_TO_TERRAIN
{
if ( perVertex )
{
eq.getElevations( geom->asVector(), featureSRS, true, _maxRes );
// if necessary, transform the Z values (which are now in the map SRS) back
// into the feature's SRS.
if ( !vertEquiv )
{
osg::ref_ptr<const SpatialReference> featureSRSwithMapVertDatum =
SpatialReference::create(featureSRS->getHorizInitString(), mapSRS->getVertInitString());
osg::Vec3d tempgeo;
for( unsigned i=0; i<geom->size(); ++i )
{
osg::Vec3d& p = (*geom)[i];
featureSRSwithMapVertDatum->transform(p, featureSRS, p);
}
}
}
else // per-centroid
{
osgEarth::Bounds bounds = geom->getBounds();
const osg::Vec2d& center = bounds.center2d();
GeoPoint centroid(featureSRS, center.x(), center.y());
double centroidElevation;
osg::ref_ptr<const SpatialReference> featureSRSWithMapVertDatum;
if ( !vertEquiv )
featureSRSWithMapVertDatum = SpatialReference::create(featureSRS->getHorizInitString(), mapSRS->getVertInitString());
if ( eq.getElevation( centroid, centroidElevation, _maxRes ) )
{
for( unsigned i=0; i<geom->size(); ++i )
{
osg::Vec3d& p = (*geom)[i];
p.z() = centroidElevation;
if ( !vertEquiv )
{
featureSRSWithMapVertDatum->transform(p, featureSRS, p);
}
}
}
}
}
if ( !collectHATs )
{
for( Geometry::iterator i = geom->begin(); i != geom->end(); ++i )
{
i->z() *= scaleZ;
i->z() += offsetZ;
}
}
}
if ( minHAT != DBL_MAX )
{
feature->set( "__min_hat", minHAT );
feature->set( "__max_hat", maxHAT );
}
if ( minTerrainZ != DBL_MAX )
{
feature->set( "__min_terrain_z", minTerrainZ );
feature->set( "__max_terrain_z", maxTerrainZ );
}
}
}