Isis Developer Reference
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Shape model that uses the Bullet library to perform ray tracing. More...
#include <BulletShapeModel.h>
Public Member Functions | |
BulletShapeModel () | |
Default constructor that creates a shape model without any internal model. | |
BulletShapeModel (Target *target, Pvl &pvl) | |
Constructor provided for instantiation from an ISIS cube. | |
BulletShapeModel (const QString &shapefile, Target *target, Pvl &pvl) | |
BulletShapeModel (BulletTargetShape *shape, Target *target, Pvl &pvl) | |
Constructor for creating new shape model from an existing target shape. | |
BulletShapeModel (BulletWorldManager *model, Target *target, Pvl &pvl) | |
Constructor for creating a new shape model an existing Bullet World. | |
~BulletShapeModel () | |
Destructor. | |
double | getTolerance () const |
Returns the occlusion tolerance in kilometers. | |
void | setTolerance (const double &tolerance) |
Sets the occlusion tolerance. | |
bool | intersectSurface (std::vector< double > observerPos, std::vector< double > lookDirection) |
This method computes a DEM intercept point given an observer location and look direction using the Bullet model. | |
virtual bool | intersectSurface (const Latitude &lat, const Longitude &lon, const std::vector< double > &observerPos, const bool &checkOcclusion=true) |
Compute the intersection at a specified latitude and longitude. | |
virtual bool | intersectSurface (const SurfacePoint &surfpt, const std::vector< double > &observerPos, const bool &checkOcclusion=true) |
Compute the intersection at surface point. | |
virtual void | setSurfacePoint (const SurfacePoint &surfacePoint) |
Set the internal surface point. | |
virtual void | clearSurfacePoint () |
Clear the saved surface point and reset the saved intersection. | |
void | calculateDefaultNormal () |
Calculate the surface normal of the ellipsoid as the default. | |
bool | isDEM () const |
Indicates that this shape model is not from a DEM. | |
void | setLocalNormalFromIntercept () |
Set the normal vector to the intercept point normal. | |
void | calculateLocalNormal (QVector< double * > cornerNeighborPoints) |
Compute the normal for a local region of surface points. | |
void | calculateSurfaceNormal () |
compute the ellipsoid surface normal of the target | |
Distance | localRadius (const Latitude &lat, const Longitude &lon) |
Compute the radius of the body at a lat/lon point. | |
QVector< double > | ellipsoidNormal () |
Compute the true surface normal vector of an ellipsoid. | |
const BulletWorldManager & | model () const |
Returns a direct reference to the Bullet world that contains the target shape and can perform ray casts. | |
virtual bool | isVisibleFrom (const std::vector< double > observerPos, const std::vector< double > lookDirection) |
Check if the saved intercept is visible from a observer with a given look direction. | |
void | Initialize () |
Initializes the ShapeModel private variables. | |
virtual SurfacePoint * | surfaceIntersection () const |
Returns the surface intersection for this ShapeModel. | |
bool | hasIntersection () |
Returns intersection status. | |
bool | hasNormal () const |
Returns surface point normal status. | |
bool | hasLocalNormal () const |
Returns surface point local normal status. | |
virtual double | emissionAngle (const std::vector< double > &sB) |
Computes and returns emission angle, in degrees, given the observer position. | |
virtual double | incidenceAngle (const std::vector< double > &uB) |
Computes and returns incidence angle, in degrees, given the illuminator position. | |
virtual double | phaseAngle (const std::vector< double > &sB, const std::vector< double > &uB) |
Computes and returns phase angle, in degrees, given the positions of the observer and illuminator. | |
QString | name () const |
Gets the shape name. | |
void | setHasIntersection (bool b) |
Sets the flag to indicate whether this ShapeModel has an intersection. | |
virtual std::vector< double > | normal () |
Returns the surface normal at the current intersection point. | |
virtual std::vector< double > | localNormal () |
Returns the local surface normal at the current intersection point. | |
Protected Member Functions | |
void | setNormal (const std::vector< double >) |
Sets the surface normal for the currect intersection point. | |
void | setNormal (const double a, const double b, const double c) |
Sets the surface normal for the currect intersection point. | |
void | setLocalNormal (const std::vector< double >) |
Sets the local normal for the currect intersection point. | |
void | setLocalNormal (const double a, const double b, const double c) |
Sets the local normal for the currect intersection point. | |
void | setName (QString name) |
Sets the shape name. | |
void | calculateEllipsoidalSurfaceNormal () |
Calculates the ellipsoidal surface normal. | |
bool | hasEllipsoidIntersection () |
Returns the status of the ellipsoid model intersection. | |
bool | intersectEllipsoid (const std::vector< double > observerPosRelativeToTarget, const std::vector< double > &observerLookVectorToTarget) |
Finds the intersection point on the ellipsoid model using the given position of the observer (spacecraft) and direction vector from the observer to the target (body). | |
bool | hasValidTarget () const |
Returns the status of the target. | |
std::vector< Distance > | targetRadii () const |
Returns the radii of the body in km. | |
void | setHasNormal (bool status) |
Sets the flag to indicate whether this ShapeModel has a surface normal. | |
void | setHasLocalNormal (bool status) |
Sets the flag to indicate whether this ShapeModel has a local normal. | |
double | resolution () |
Convenience method to get pixel resolution (m/pix) at current intersection point. | |
Shape model that uses the Bullet library to perform ray tracing.
Isis::BulletShapeModel::BulletShapeModel | ( | ) |
Default constructor that creates a shape model without any internal model.
References Isis::ShapeModel::setName().
Constructor provided for instantiation from an ISIS cube.
This constructor is typically used for and ISIS cube that has been initialized by spiceinit. The DEM name should be that of a NAIF DSK file. This constructor will throw an exception if it fails to open the DSK file.
target | Target object describing the observed body |
pvl | ISIS Cube label. Extracts the name of the DEM from the Kernels group |
References _FILEINFO_, Isis::PvlContainer::hasKeyword(), Isis::BulletTargetShape::load(), Isis::ShapeModel::setName(), Isis::PvlObject::Traverse, and Isis::IException::User.
Isis::BulletShapeModel::BulletShapeModel | ( | BulletTargetShape * | shape, |
Target * | target, | ||
Pvl & | pvl ) |
Constructor for creating new shape model from an existing target shape.
shape | The existing target shape to use with this shape model |
target | Target object describing the observed body |
pvl | Unused |
References Isis::BulletTargetShape::name(), and Isis::ShapeModel::setName().
Isis::BulletShapeModel::BulletShapeModel | ( | BulletWorldManager * | model, |
Target * | target, | ||
Pvl & | pvl ) |
Constructor for creating a new shape model an existing Bullet World.
Assumes the world contains at least one active object
model | The existing Bullet world model to use |
target | Target object describing the observed body |
pvl | Unused |
Isis::BulletShapeModel::~BulletShapeModel | ( | ) |
Destructor.
Cleanup is handled by Bullet routines and QPointers.
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virtual |
Calculate the surface normal of the ellipsoid as the default.
Implements Isis::ShapeModel.
References calculateSurfaceNormal().
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protectedinherited |
Calculates the ellipsoidal surface normal.
References _FILEINFO_, Isis::IException::Programmer, and Isis::ShapeModel::surfaceIntersection().
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virtual |
Compute the normal for a local region of surface points.
This method will calculate the surface normal of an assumed very local region of points. This method is provided to fullfil the specs of the ShapeModel class but this approach is not the most efficent means to accomplish this for a pre-exising intercept point. See setLocalNormalFromIntercept() for this.
The ShapeModel class makes the assumption that the four pixel corners of the center intercept point forms a plane from which a surface normal can be computed. For the Naif DSK plate model, we have already identified the plate (see m_intercept) from the DSK plate model (m_model) of the intercept point that provides it directly. That is what setLocalNormalFromIntercept() provides.
So, this implementation will compute the centroid of the neighboring points and make a determination if it intercepts the current intercept plate as defined by m_intercept - if it is valid. If it does not exist or does not intercept the plate, a new intercept point is computed and returned here.
neighborPoints | Input body-fixed points to compute normal for |
Implements Isis::ShapeModel.
References _FILEINFO_, Isis::ShapeModel::hasIntersection(), Isis::IException::Programmer, and setLocalNormalFromIntercept().
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compute the ellipsoid surface normal of the target
Implements Isis::ShapeModel.
References ellipsoidNormal(), and Isis::ShapeModel::setNormal().
Referenced by calculateDefaultNormal().
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Clear the saved surface point and reset the saved intersection.
Reimplemented from Isis::ShapeModel.
Referenced by intersectSurface(), intersectSurface(), and intersectSurface().
QVector< double > Isis::BulletShapeModel::ellipsoidNormal | ( | ) |
Compute the true surface normal vector of an ellipsoid.
This routine is used instead of the one provided by the ShapeModel implementation. This is primarly because ShapeModel::calculateEllipsoidalSurfaceNormal() is only suitable for a spheroid. This implementation is intended for irregular bodies so we expect triaxial ellipsoids.
References _FILEINFO_, Isis::NaifStatus::CheckErrors(), Isis::ShapeModel::hasIntersection(), Isis::ShapeModel::hasValidTarget(), Isis::IException::Programmer, Isis::ShapeModel::surfaceIntersection(), and Isis::ShapeModel::targetRadii().
Referenced by calculateSurfaceNormal().
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virtualinherited |
Computes and returns emission angle, in degrees, given the observer position.
Emission Angle: The angle between the surface normal vector at the intersection point and the vector from the intersection point to the observer (usually the spacecraft). The emission angle varies from 0 degrees when the observer is viewing the sub-spacecraft point (nadir viewing) to 90 degrees when the intercept is tangent to the surface of the target body. Thus, higher values of emission angle indicate more oblique viewing of the target.
observerBodyFixedPosition | Three dimensional position of the observer, in the coordinate system of the target body. |
Reimplemented in Isis::PlaneShape.
References Isis::ShapeModel::calculateDefaultNormal(), Isis::ShapeModel::hasNormal(), Isis::RAD2DEG, and Isis::ShapeModel::surfaceIntersection().
Referenced by Isis::ShapeModel::isVisibleFrom().
double Isis::BulletShapeModel::getTolerance | ( | ) | const |
Returns the occlusion tolerance in kilometers.
Referenced by isVisibleFrom().
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protectedinherited |
Returns the status of the ellipsoid model intersection.
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inherited |
Returns intersection status.
Referenced by Isis::DemShape::calculateDefaultNormal(), calculateLocalNormal(), Isis::EllipsoidShape::calculateLocalNormal(), Isis::EmbreeShapeModel::calculateLocalNormal(), Isis::NaifDskShape::calculateLocalNormal(), ellipsoidNormal(), Isis::EmbreeShapeModel::ellipsoidNormal(), Isis::NaifDskShape::ellipsoidNormal(), Isis::EmbreeShapeModel::intersectSurface(), intersectSurface(), Isis::EmbreeShapeModel::intersectSurface(), intersectSurface(), Isis::DemShape::intersectSurface(), Isis::EmbreeShapeModel::intersectSurface(), Isis::EquatorialCylindricalShape::intersectSurface(), Isis::ShapeModel::isVisibleFrom(), Isis::CSMCamera::SetGround(), setLocalNormalFromIntercept(), and Isis::NaifDskShape::setLocalNormalFromIntercept().
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inherited |
Returns surface point local normal status.
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inherited |
Returns surface point normal status.
Referenced by Isis::ShapeModel::emissionAngle(), Isis::EmbreeShapeModel::incidenceAngle(), and Isis::ShapeModel::incidenceAngle().
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protectedinherited |
Returns the status of the target.
If it is NULL, this method returns false.
Referenced by ellipsoidNormal(), Isis::EmbreeShapeModel::ellipsoidNormal(), Isis::NaifDskShape::ellipsoidNormal(), Isis::ShapeModel::resolution(), and Isis::ShapeModel::targetRadii().
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virtualinherited |
Computes and returns incidence angle, in degrees, given the illuminator position.
Incidence Angle: The angle between the surface normal vector at the intersection point and the vector from the intersection point to the illuminator (usually the sun).
Note: this method does not use the surface model.
illuminatorBodyFixedPosition | Three dimensional position for the illuminator, in the body-fixed coordinate system. |
Reimplemented in Isis::EmbreeShapeModel, and Isis::PlaneShape.
References Isis::ShapeModel::calculateDefaultNormal(), Isis::ShapeModel::hasNormal(), Isis::RAD2DEG, and Isis::ShapeModel::surfaceIntersection().
Referenced by Isis::EmbreeShapeModel::incidenceAngle().
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inherited |
Initializes the ShapeModel private variables.
Referenced by Isis::ShapeModel::ShapeModel(), and Isis::ShapeModel::ShapeModel().
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protectedinherited |
Finds the intersection point on the ellipsoid model using the given position of the observer (spacecraft) and direction vector from the observer to the target (body).
observerBodyFixedPosition | Three dimensional position of the observer, in the coordinate system of the target body. |
observerLookVectorToTarget | Three dimensional direction vector from the observer to the target. |
References Isis::NaifStatus::CheckErrors(), Isis::ShapeModel::clearSurfacePoint(), Isis::SurfacePoint::FromNaifArray(), and Isis::ShapeModel::targetRadii().
Referenced by Isis::DemShape::intersectSurface(), and Isis::EllipsoidShape::intersectSurface().
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Compute the intersection at a specified latitude and longitude.
The intersection can also be checked for occlusion from an observer.
If more than one intersection exist at the latitude and longitude, then the intersection closest to the observer is saved. If occlusion is being checked, then the closest non-occluded intersection is saved.
lat | The latitude to compute the intersection at. |
lon | The longitude to compute the intersection at. |
observerPos | The observer used for occlusion and deciding between multiple intersections. |
checkOcclusion | If occlusion should be checked. |
Reimplemented from Isis::ShapeModel.
References clearSurfacePoint(), and Isis::ShapeModel::hasIntersection().
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Compute the intersection at surface point.
The intersection can also be checked for occlusion from an observer.
The intersection is found by casting a ray from the center of the body through the surface point. If multiple intersections are found, then the intersection closest to the surface point is saved. If occlusion is being checked, then the closest non-occluded point is saved.
surfpt | Surface point to find the intersection at |
observerPos | The observer used for occlusion and deciding between multiple intersections. |
checkOcclusion | If occlusion should be checked. |
Reimplemented from Isis::ShapeModel.
References clearSurfacePoint(), and Isis::ShapeModel::hasIntersection().
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This method computes a DEM intercept point given an observer location and look direction using the Bullet model.
observerPos | Position of observer in body fixed coordiates |
lookDirection | Look direction (ray) from the observer |
Implements Isis::ShapeModel.
References clearSurfacePoint().
Referenced by setSurfacePoint().
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Indicates that this shape model is not from a DEM.
Since this method returns false for this class, the Camera class will not calculate the local normal using neighbor points.
Implements Isis::ShapeModel.
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Check if the saved intercept is visible from a observer with a given look direction.
observerPos | The position of the observer in body-fixed kilometers. |
lookDirection | The observer look direction inf body-fixed coordinates. |
Reimplemented from Isis::ShapeModel.
References getTolerance(), Isis::BulletClosestRayCallback::isValid(), Isis::BulletClosestRayCallback::isVisible(), Isis::BulletClosestRayCallback::normal(), Isis::BulletClosestRayCallback::point(), and Isis::RAD2DEG.
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virtualinherited |
Returns the local surface normal at the current intersection point.
Note: This method will throw an error if the normal doesn't exist. Use the hasLocalNormal() method to verify before calling this method.
References _FILEINFO_, and Isis::IException::Unknown.
Referenced by Isis::EllipsoidShape::calculateSurfaceNormal(), and Isis::EmbreeShapeModel::incidenceAngle().
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Compute the radius of the body at a lat/lon point.
A ray is cast from the center of the body through the lat/lon point. The intersection closest to the center of the body is used to compute the radius.
NOTE this call does not update the internal state of the intercept point. Use intersectSurface(lat, lon) for that.
Implements Isis::ShapeModel.
References Isis::BulletAllHitsRayCallback::hit(), Isis::Distance::Kilometers, and Isis::BulletClosestRayCallback::point().
const BulletWorldManager & Isis::BulletShapeModel::model | ( | ) | const |
Returns a direct reference to the Bullet world that contains the target shape and can perform ray casts.
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inherited |
Gets the shape name.
Referenced by Isis::Target::restoreShape(), Isis::Camera::SetGround(), Isis::CSMCamera::SetGround(), and Isis::ShapeModel::setName().
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virtualinherited |
Returns the surface normal at the current intersection point.
Note: This method will throw an error if the normal doesn't exist. Use the hasNormal() method to verify before calling this method.
References _FILEINFO_, and Isis::IException::Unknown.
Referenced by Isis::DemShape::calculateDefaultNormal(), Isis::DemShape::calculateLocalNormal(), Isis::EllipsoidShape::calculateLocalNormal(), Isis::EmbreeShapeModel::incidenceAngle(), Isis::IsisShape::intersect(), Isis::ShapeModel::setLocalNormal(), setLocalNormalFromIntercept(), and Isis::ShapeModel::setNormal().
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virtualinherited |
Computes and returns phase angle, in degrees, given the positions of the observer and illuminator.
Phase Angle: The angle between the vector from the intersection point to the observer (usually the spacecraft) and the vector from the intersection point to the illuminator (usually the sun).
observerBodyFixedPosition | Three dimensional position of the observer, in the coordinate system of the target body. |
illuminatorBodyFixedPosition | Three dimensional position for the illuminator, in the body-fixed coordinate system. |
References Isis::RAD2DEG, and Isis::ShapeModel::surfaceIntersection().
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protectedinherited |
Convenience method to get pixel resolution (m/pix) at current intersection point.
References _FILEINFO_, Isis::ShapeModel::hasValidTarget(), Isis::IException::Programmer, Isis::Spice::resolution(), and Isis::Target::spice().
Referenced by Isis::DemShape::intersectSurface().
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inherited |
Sets the flag to indicate whether this ShapeModel has an intersection.
b | Indicates whether there is an intersection. |
References Isis::ShapeModel::setHasLocalNormal(), and Isis::ShapeModel::setHasNormal().
Referenced by Isis::ShapeModel::clearSurfacePoint(), Isis::DemShape::intersectSurface(), Isis::EmbreeShapeModel::intersectSurface(), Isis::EquatorialCylindricalShape::intersectSurface(), Isis::PlaneShape::intersectSurface(), and Isis::CSMCamera::SetGround().
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protectedinherited |
Sets the flag to indicate whether this ShapeModel has a local normal.
status | Indicates whether there is a normal. |
Referenced by Isis::DemShape::calculateLocalNormal(), Isis::EllipsoidShape::calculateLocalNormal(), Isis::EmbreeShapeModel::clearSurfacePoint(), Isis::ShapeModel::setHasIntersection(), and Isis::ShapeModel::setSurfacePoint().
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protectedinherited |
Sets the flag to indicate whether this ShapeModel has a surface normal.
status | Indicates whether there is a normal. |
Referenced by Isis::DemShape::calculateDefaultNormal(), Isis::EmbreeShapeModel::clearSurfacePoint(), Isis::ShapeModel::setHasIntersection(), and Isis::ShapeModel::setSurfacePoint().
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protectedinherited |
Sets the local normal for the currect intersection point.
Note: This method will throw an error if this ShapeModel doesn't have and intersection. Use the hasIntersection() method to verify before calling this method.
a | First coordinate value for the three dimensional local normal. |
b | Second coordinate value for the three dimensional local normal. |
c | Third coordinate value for the three dimensional local normal. |
References _FILEINFO_, and Isis::IException::Unknown.
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protectedinherited |
Sets the local normal for the currect intersection point.
Note: This method will throw an error if this ShapeModel doesn't have an intersection. Use the hasIntersection() method to verify before calling this method.
normal | Three dimensional local normal vector. |
References _FILEINFO_, Isis::ShapeModel::normal(), and Isis::IException::Unknown.
Referenced by Isis::DemShape::calculateLocalNormal(), Isis::EllipsoidShape::calculateLocalNormal(), setLocalNormalFromIntercept(), and Isis::NaifDskShape::setLocalNormalFromIntercept().
void Isis::BulletShapeModel::setLocalNormalFromIntercept | ( | ) |
Set the normal vector to the intercept point normal.
This method will reassign the ShapeModel normal to the current intercept point shape (which is a triangular plate) normal. If an intercept point is not defined, an error will ensue.
References _FILEINFO_, Isis::ShapeModel::hasIntersection(), Isis::ShapeModel::normal(), Isis::BulletClosestRayCallback::normal(), Isis::IException::Programmer, and Isis::ShapeModel::setLocalNormal().
Referenced by calculateLocalNormal().
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protectedinherited |
Sets the shape name.
name | The name of the ShapeModel. |
References Isis::ShapeModel::name().
Referenced by BulletShapeModel(), BulletShapeModel(), BulletShapeModel(), Isis::DemShape::DemShape(), Isis::DemShape::DemShape(), Isis::EllipsoidShape::EllipsoidShape(), Isis::EllipsoidShape::EllipsoidShape(), Isis::EmbreeShapeModel::EmbreeShapeModel(), Isis::EmbreeShapeModel::EmbreeShapeModel(), Isis::EmbreeShapeModel::EmbreeShapeModel(), Isis::EquatorialCylindricalShape::EquatorialCylindricalShape(), Isis::NaifDskShape::NaifDskShape(), Isis::NaifDskShape::NaifDskShape(), Isis::PlaneShape::PlaneShape(), Isis::PlaneShape::PlaneShape(), and Isis::PlaneShape::PlaneShape().
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protectedinherited |
Sets the surface normal for the currect intersection point.
Note: This method will throw an error if this ShapeModel doesn't have and intersection. Use the hasIntersection() method to verify before calling this method.
a | First coordinate value for the three dimensional surface normal. |
b | Second coordinate value for the three dimensional surface normal. |
c | Third coordinate value for the three dimensional surface normal. |
References _FILEINFO_, and Isis::IException::Unknown.
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protectedinherited |
Sets the surface normal for the currect intersection point.
Note: This method will throw an error if this ShapeModel doesn't have an intersection. Use the hasIntersection() method to verify before calling this method.
normal | Three dimensional surface normal vector. |
References _FILEINFO_, Isis::ShapeModel::normal(), and Isis::IException::Unknown.
Referenced by Isis::DemShape::calculateDefaultNormal(), calculateSurfaceNormal(), Isis::EllipsoidShape::calculateSurfaceNormal(), Isis::EmbreeShapeModel::calculateSurfaceNormal(), Isis::NaifDskShape::calculateSurfaceNormal(), Isis::EmbreeShapeModel::incidenceAngle(), and Isis::PlaneShape::intersectSurface().
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Set the internal surface point.
A new intersection based on the surface point will be computed and saved.
surfacePoint | The new surface point |
Reimplemented from Isis::ShapeModel.
References intersectSurface().
void Isis::BulletShapeModel::setTolerance | ( | const double & | tolerance | ) |
Sets the occlusion tolerance.
tolerance | The new occlusion tolerance in kilometers. |
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virtualinherited |
Returns the surface intersection for this ShapeModel.
Referenced by Isis::DemShape::calculateDefaultNormal(), Isis::ShapeModel::calculateEllipsoidalSurfaceNormal(), Isis::DemShape::calculateLocalNormal(), Isis::EllipsoidShape::calculateLocalNormal(), Isis::Sensor::Coordinate(), ellipsoidNormal(), Isis::EmbreeShapeModel::ellipsoidNormal(), Isis::NaifDskShape::ellipsoidNormal(), Isis::PlaneShape::emissionAngle(), Isis::ShapeModel::emissionAngle(), Isis::PlaneShape::incidenceAngle(), Isis::ShapeModel::incidenceAngle(), Isis::IsisShape::intersect(), Isis::DemShape::intersectSurface(), Isis::EquatorialCylindricalShape::intersectSurface(), Isis::PlaneShape::intersectSurface(), Isis::EmbreeShapeModel::isVisibleFrom(), Isis::PlaneShape::localRadius(), and Isis::ShapeModel::phaseAngle().
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protectedinherited |
Returns the radii of the body in km.
The radii are obtained from the target. Note: This method will throw an error if the ShapeModel does not have a valid target. Use the hasValidTarget() method to verify before calling this method.
References _FILEINFO_, Isis::ShapeModel::hasValidTarget(), Isis::IException::Programmer, and Isis::Target::radii().
Referenced by Isis::DemShape::calculateDefaultNormal(), Isis::EllipsoidShape::calculateLocalNormal(), ellipsoidNormal(), Isis::EmbreeShapeModel::ellipsoidNormal(), Isis::NaifDskShape::ellipsoidNormal(), Isis::ShapeModel::intersectEllipsoid(), Isis::EquatorialCylindricalShape::intersectSurface(), and Isis::EllipsoidShape::localRadius().