---
name: "SbPlaneProjector"
section: "3"
platform: "linux"
package: "coin"
version: "1:4.0.10-1"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/SbPlaneProjector"
---

# SbPlaneProjector(3)

The SbPlaneProjector class projects 2D points to 3D points in a plane.

## NAME

SbPlaneProjector - The **SbPlaneProjector** class projects 2D points to 3D points in a plane.

## SYNOPSIS

\#include \<Inventor/projectors/SbPlaneProjector.h\>

Inherits **SbProjector**.

### Public Member Functions

**SbPlaneProjector** (const SbBool orient=FALSE)\
 **SbPlaneProjector** (const **SbPlane** &**plane**, const SbBool orient=FALSE)\
 virtual **SbProjector** \* **copy** (void) const\
 virtual **SbVec3f** **project** (const **SbVec2f** &point)\
 virtual SbBool **tryProject** (const **SbVec2f** &point, const float epsilon, **SbVec3f** &result)\
 void **setPlane** (const **SbPlane** &**plane**)\
 const **SbPlane** & **getPlane** (void) const\
 void **setOrientToEye** (const SbBool orienttoeye)\
 SbBool **isOrientToEye** (void) const\
 virtual **SbVec3f** **getVector** (const **SbVec2f** &viewpos1, const **SbVec2f** &viewpos2)\
 virtual **SbVec3f** **getVector** (const **SbVec2f** &viewpos)\
 void **setStartPosition** (const **SbVec2f** &viewpos)\
 void **setStartPosition** (const **SbVec3f** &point)\

Public Member Functions inherited from **SbProjector** virtual void **setViewVolume** (const **SbViewVolume** &vol)\
 const **SbViewVolume** & **getViewVolume** (void) const\
 virtual void **setWorkingSpace** (const **SbMatrix** &space)\
 const **SbMatrix** & **getWorkingSpace** (void) const\

### Protected Member Functions

void **setupPlane** (void)\

Protected Member Functions inherited from **SbProjector** **SbProjector** (void)\
 virtual **~SbProjector** ()\
 **SbLine** **getWorkingLine** (const **SbVec2f** &point) const\
 float **findVanishingDistance** (void) const\
 SbBool **verifyProjection** (const **SbVec3f** &projpt) const\

### Protected Attributes

**SbPlane** **plane**\
 **SbPlane** **nonOrientPlane**\
 SbBool **orientToEye**\
 SbBool **needSetup**\
 **SbVec3f** **lastPoint**\

Protected Attributes inherited from **SbProjector** **SbViewVolume** **viewVol**\
 **SbMatrix** **worldToWorking**\
 **SbMatrix** **workingToWorld**\

## Detailed Description

The **SbPlaneProjector** class projects 2D points to 3D points in a plane.

The 3D projection of the 2D coordinates is for this projector class constrained to lie inside a predefined 3D plane.

**See also**

**SbLineProjector**

## Constructor & Destructor Documentation

### SbPlaneProjector::SbPlaneProjector (const SbBool orient = FALSE)

Constructor. Sets up a projection plane parallel with the XY-plane in world coordinates.

### SbPlaneProjector::SbPlaneProjector (const SbPlane & plane, const SbBool orient = FALSE)

Constructor taking an explicit projection *plane* definition.

## Member Function Documentation

### SbProjector \* SbPlaneProjector::copy (void ) const \[virtual\]

Construct and return a copy of this projector. The caller is responsible for destructing the new instance.

**Note that if the Coin library has been built as a DLL under Microsoft Windows and you use this method from application code, you** *must* **make sure that both the Coin DLL and the application executable are using the same instance of a C Run-Time (CRT) library. Otherwise, you** *will* **get memory heap corruption upon deallocating the returned instances, eventually leading to mysterious crashes.**\

*Implements* **SbProjector***.*

### SbVec3f SbPlaneProjector::project (const SbVec2f & point) \[virtual\]

*Projects 2D point into a 3D point within the current projection plane.*

*Implements* **SbProjector***.*

### SbBool SbPlaneProjector::tryProject (const SbVec2f & point, const float epsilon, SbVec3f & result) \[virtual\]

*Try projecting the 2D point from normalized viewport coordinates to a 3D point. The mapping will be done in accordance with the type of the projector.*

*If the projection can't be done safely (for instance when the projection plane or line is parallel to the view volume projection), this function should return FALSE.*

*Default implementation will call* **project()** *and always return TRUE, but subclasses can override this behavior to support safe projections.*

**Since**

*Coin 3.0*

*Reimplemented from* **SbProjector***.*

### void SbPlaneProjector::setPlane (const SbPlane & planeref)

*Set a new projection plane.*

### const SbPlane & SbPlaneProjector::getPlane (void ) const

*Returns the current projection plane.*

### void SbPlaneProjector::setOrientToEye (const SbBool orienttoeye)

*Sets whether or not the plane should always be oriented towards the "eye" of the viewer.*

### SbBool SbPlaneProjector::isOrientToEye (void ) const

*Returns the state of the plane orientation flag.*

### SbVec3f SbPlaneProjector::getVector (const SbVec2f & viewpos1, const SbVec2f & viewpos2) \[virtual\]

*Returns a vector between the projected 3D points of viewpos1 and viewpos2.*

### SbVec3f SbPlaneProjector::getVector (const SbVec2f & viewpos) \[virtual\]

*Returns a vector between the last projected point and the projected 3D point of viewpos.*

### void SbPlaneProjector::setStartPosition (const SbVec2f & viewpos)

*Explicitly set position of initial projection, so we get correct values for later calls to* **getVector()** *etc.*

### void SbPlaneProjector::setStartPosition (const SbVec3f & point)

*Explicitly set position of initial projection, so we get correct values for later calls to* **getVector()** *etc.*

### void SbPlaneProjector::setupPlane (void ) \[protected\]

*Should be called whenever* **SbPlaneProjector::needSetup** *is* TRUE*. Will recalculate projection plane.*

## Member Data Documentation

### SbPlane SbPlaneProjector::plane \[protected\]

*The projection plane.*

### SbPlane SbPlaneProjector::nonOrientPlane \[protected\]

*The "original" plane which was set (as opposed to the recalculated projection plane according to the* **SbPlaneProjector::orientToEye** *setting).*

### SbBool SbPlaneProjector::orientToEye \[protected\]

*Which direction the plane is oriented.*

### SbBool SbPlaneProjector::needSetup \[protected\]

*Set to* TRUE *whenever the plane needs to be recalculated according to the setting of the* **SbPlaneProjector::orientToEye** *flag.*

### SbVec3f SbPlaneProjector::lastPoint \[protected\]

*Stores the previously projected 3D point.*

## Author

*Generated automatically by Doxygen for Coin from the source code.*