# SbSphericalProjection Class Reference [Basics]

Spherical coordinate projection. More...

`#include <Inventor/projection/SbSphericalProjection.h>`

Inheritance diagram for SbSphericalProjection: List of all members.

## Public Member Functions

SbSphericalProjection ()
SbSphericalProjection (SoProjection *node)
virtual ~SbSphericalProjection ()
virtual void inverse (SbVec3f &point)
virtual bool getProjectedBoundingBox (SbBox3f &bbox)

## Detailed Description

Spherical coordinate projection.

This class performs a spherical coordinate projection and is normally used with an SoProjection or SoGeoProjection node.

Spherical coordinates can be represented using the usual coordinate classes (SbVec3f, SoMFVec3f, etc) but the three values are considered to be

• Longitude: an angle measured in degrees in the interval [-180,180]
• Latitude: an angle measured in degrees in the interval [-90,90]
• Altitude (or radius): a distance in 3D units greater than zero

The parameters are :

 Name Type Index Default radius float 0 0 scaleRatio float 1 1

The radius parameter is an offset added to each altitude value before projection. This is useful when the altitude values are, for example, relative to sea level.

The scaleRatio parameter is a multiplicative ratio applied to altitude values before projection. This is useful to exaggerate altitudes for visualization purposes.

The spherical projection of a point P(lon,lat,alt) is computed as follows:

```    newLon = lon * degreeToRadians
newLat = lat * degreeToRadians
newRadius = radius + alt * scaleRatio

x = newRadius*cos(newlat)*cos(newlon)
y = newRadius*cos(newlat)*sin(newlon)
z = newRadius*sin(newlat)
```

### SEE ALSO

See related examples:

VolumeProjection

## Constructor & Destructor Documentation

 SbSphericalProjection::SbSphericalProjection ( )

Constructor.

 SbSphericalProjection::SbSphericalProjection ( SoProjection * node )

Constructor.

 virtual SbSphericalProjection::~SbSphericalProjection ( ) ` [virtual]`

Destructor.

## Member Function Documentation

 virtual bool SbSphericalProjection::getProjectedBoundingBox ( SbBox3f & bbox ) ` [virtual]`

Compute projected bounding box.

Reimplemented from SbProjection.

 virtual void SbSphericalProjection::inverse ( SbVec3f & point ) ` [virtual]`

Apply the inverse coordinate to one point. Modifies the given object.

Reimplemented from SbProjection.

The documentation for this class was generated from the following file:

Open Inventor Toolkit reference manual, generated on 8 Apr 2021
Copyright © Thermo Fisher Scientific All rights reserved.
http://www.openinventor.com/