SbSphereSheetProjector.3coin3 - Man Page

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

Synopsis

#include <Inventor/projectors/SbSphereSheetProjector.h>

Inherits SbSphereProjector.

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 <stdio.h>
#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:

Constructor & Destructor Documentation

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

Constructor with explicit definition of projection sphere.

Member Function Documentation

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 is 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.