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SbSphereSheetProjector Class Reference

The SbSphereSheetProjector class projects 2D points to 3D points on a sheet covering a spherical shape. More...

#include <Inventor/projectors/SbSphereSheetProjector.h>

Inheritance diagram for SbSphereSheetProjector:
SbSphereProjector SbProjector

Public Member Functions

 SbSphereSheetProjector (const SbBool orienttoeye=TRUE)
 SbSphereSheetProjector (const SbSphere &sph, const SbBool orienttoeye=TRUE)
virtual SbProjectorcopy (void) const
virtual SbVec3f project (const SbVec2f &point)
virtual SbRotation getRotation (const SbVec3f &point1, const SbVec3f &point2)
- Public Member Functions inherited from SbSphereProjector
SbVec3f projectAndGetRotation (const SbVec2f &point, SbRotation &rot)
void setSphere (const SbSphere &sph)
const SbSpheregetSphere (void) const
void setOrientToEye (const SbBool orienttoeye)
SbBool isOrientToEye (void) const
void setFront (const SbBool infront)
SbBool isFront (void) const
SbBool isPointInFront (const SbVec3f &point) const
virtual void setWorkingSpace (const SbMatrix &space)
- Public Member Functions inherited from SbProjector
virtual void setViewVolume (const SbViewVolume &vol)
const SbViewVolumegetViewVolume (void) const
const SbMatrixgetWorkingSpace (void) const
virtual SbBool tryProject (const SbVec2f &point, const float epsilon, SbVec3f &result)

Protected Member Functions

void setupPlane (void)
- Protected Member Functions inherited from SbSphereProjector
 SbSphereProjector (const SbBool orienttoeye)
 SbSphereProjector (const SbSphere &s, const SbBool orienttoeye)
SbBool intersectSphereFront (const SbLine &l, SbVec3f &result)
- 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

SbVec3f workingProjPoint
SbVec3f planePoint
SbVec3f planeDir
float planeDist
SbPlane tolPlane
- Protected Attributes inherited from SbSphereProjector
SbBool intersectFront
SbSphere sphere
SbBool orientToEye
SbBool needSetup
SbVec3f lastPoint
- Protected Attributes inherited from SbProjector
SbViewVolume viewVol
SbMatrix worldToWorking
SbMatrix workingToWorld

Detailed Description

The SbSphereSheetProjector class projects 2D points to 3D points on a sheet covering a spherical shape.

The following stand-alone example shows how screen space coordinates projects into 3D when mapped with an SbSphereSheetProjector. It outputs the resulting projections as an SoPointSet in a Inventor-file on stdout:

#include <cstdio>
#include <Inventor/SbLinear.h>
#include <Inventor/projectors/SbSphereSheetProjector.h>
#include <Inventor/SoDB.h>
const float START = 0.0f;
const float END = 1.0f;
const float STEPS = 50.0f;
const float STEPSIZE = ((END - START) / STEPS);
SbSphere s(SbVec3f(0, 0, 0), 0.8);
SbSphereSheetProjector ssp(s, TRUE); // last argument is orientToEye
SbViewVolume volume;
volume.ortho(-1, 1, -1, 1, -1, 1);
(void)fprintf(stdout, "#Inventor V2.1 ascii\n\n"
"Separator {\n"
" Coordinate3 {\n"
" point [\n");
for (float i=START; i <= END; i += STEPSIZE) {
for (float j=START; j <= END; j += STEPSIZE) {
SbVec3f v = ssp.project(SbVec2f(j, i));
(void)fprintf(stdout, "\t%f %f %f,\n", v[0], v[1], v[2]);
(void)fprintf(stdout, " ]\n"
" }\n"
" DrawStyle { pointSize 2 }\n"
" PointSet { }\n"
return 0;

The projections to 3D points in the resulting Inventor-file looks like this:

Rendering of Example Resulting Projections

Constructor & Destructor Documentation

◆ SbSphereSheetProjector() [1/2]

SbSphereSheetProjector::SbSphereSheetProjector ( const SbBool  orienttoeye = TRUE)

Constructor. Uses default sphere defintion, see SbSphereProjector::SbSphereProjector().

orienttoeye decides whether or not the sheet should always be oriented towards the viewer.

◆ SbSphereSheetProjector() [2/2]

SbSphereSheetProjector::SbSphereSheetProjector ( const SbSphere sph,
const SbBool  orienttoeye = TRUE 

Constructor with explicit definition of projection sphere.

Member Function Documentation

◆ copy()

SbProjector * SbSphereSheetProjector::copy ( void  ) const

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.

◆ project()

SbVec3f SbSphereSheetProjector::project ( const SbVec2f point)

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

Implements SbProjector.

◆ getRotation()

SbRotation SbSphereSheetProjector::getRotation ( const SbVec3f point1,
const SbVec3f point2 

Returns rotation on the projection surface which re-orients point1 to point2.

Implements SbSphereProjector.

◆ setupPlane()

void SbSphereSheetProjector::setupPlane ( void  )

Recalculates projection surface settings after changes to the parameters.

Member Data Documentation

◆ workingProjPoint


Last projected point, in the working space coordinate system.

◆ planePoint


Position of the center of the sphere in the plane of the hyberbolic sheet.

◆ planeDir


Normal vector of the plane defining the orientation of the sheet.

◆ planeDist


This API member is considered internal to the library, as it is not likely to be of interest to the application programmer.

◆ tolPlane


The tolerance value specifying how much of the sphere is "above" the sheet.

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