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:

Public Member Functions
	SbSphereSheetProjector (const SbBool orienttoeye=TRUE)
	SbSphereSheetProjector (const SbSphere &sph, const SbBool orienttoeye=TRUE)
virtual SbProjector *	copy (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 SbSphere &	getSphere (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 SbViewVolume &	getViewVolume (void) const
const SbMatrix &	getWorkingSpace (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>

int
main(void)
{
  SoDB::init();

  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);
  ssp.setViewVolume(volume);

  (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"
                "}\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

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.

project()

SbVec3f SbSphereSheetProjector::project ( const SbVec2f &  point )

virtual

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  )

virtual

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

Implements SbSphereProjector.

setupPlane()

void SbSphereSheetProjector::setupPlane ( void  )

protected

Recalculates projection surface settings after changes to the parameters.

Member Data Documentation

workingProjPoint

SbSphereSheetProjector::workingProjPoint

protected

Last projected point, in the working space coordinate system.

planePoint

SbSphereSheetProjector::planePoint

protected

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

planeDir

SbSphereSheetProjector::planeDir

protected

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

planeDist

SbSphereSheetProjector::planeDist

protected

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

tolPlane

SbSphereSheetProjector::tolPlane

protected

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

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

• SbSphereSheetProjector.h
• SbSphereSheetProjector.cpp