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SoCamera Class Referenceabstract

The SoCamera class is the abstract base class for camera definition nodes. More...

#include <Inventor/nodes/SoCamera.h>

Inheritance diagram for SoCamera:
SoNode SoFieldContainer SoBase SoFrustumCamera SoOrthographicCamera SoPerspectiveCamera SoReversePerspectiveCamera

Public Types

enum  ViewportMapping {
  CROP_VIEWPORT_FILL_FRAME, CROP_VIEWPORT_LINE_FRAME, CROP_VIEWPORT_NO_FRAME, ADJUST_CAMERA,
  LEAVE_ALONE
}
 
enum  StereoMode { MONOSCOPIC, LEFT_VIEW, RIGHT_VIEW }
 
- Public Types inherited from SoNode
enum  NodeType {
  INVENTOR = 0x0000, VRML1 = 0x0001, VRML2 = 0x0002, INVENTOR_1 = 0x0004,
  INVENTOR_2_0 = 0x0008, INVENTOR_2_1 = 0x0010, INVENTOR_2_5 = 0x0020, INVENTOR_2_6 = 0x0040,
  COIN_1_0 = 0x0080, COIN_2_0 = 0x0100, EXTENSION = 0x0200, COIN_2_2 = 0x0400,
  COIN_2_3 = 0x0800, COIN_2_4 = 0x1000, INVENTOR_5_0 = 0x2000, COIN_2_5 = 0x4000,
  COIN_3_0 = 0x8000, INVENTOR_6_0 = 0x10000, COIN_4_0 = 0x20000
}
 

Public Member Functions

virtual SoType getTypeId (void) const
 Returns the type identification of an object derived from a class inheriting SoBase. This is used for runtime type checking and "downward" casting. More...
 
SbViewVolume getViewVolume (const SbViewportRegion &vp, SbViewportRegion &resultvp, const SbMatrix &mm=SbMatrix::identity()) const
 
void pointAt (const SbVec3f &targetpoint)
 
void pointAt (const SbVec3f &targetpoint, const SbVec3f &upvector)
 
virtual void scaleHeight (float scalefactor)=0
 
virtual SbViewVolume getViewVolume (float useaspectratio=0.0f) const =0
 
void viewAll (SoNode *const sceneroot, const SbViewportRegion &vpregion, const float slack=1.0f)
 
void viewAll (SoPath *const path, const SbViewportRegion &vpregion, const float slack=1.0f)
 
SbViewportRegion getViewportBounds (const SbViewportRegion &region) const
 
void setStereoMode (StereoMode mode)
 
StereoMode getStereoMode (void) const
 
void setStereoAdjustment (float adjustment)
 
float getStereoAdjustment (void) const
 
void setBalanceAdjustment (float adjustment)
 
float getBalanceAdjustment (void) const
 
virtual void doAction (SoAction *action)
 
virtual void callback (SoCallbackAction *action)
 
virtual void GLRender (SoGLRenderAction *action)
 
virtual void audioRender (SoAudioRenderAction *action)
 
virtual void getBoundingBox (SoGetBoundingBoxAction *action)
 
virtual void getMatrix (SoGetMatrixAction *action)
 
virtual void handleEvent (SoHandleEventAction *action)
 
virtual void rayPick (SoRayPickAction *action)
 
virtual void getPrimitiveCount (SoGetPrimitiveCountAction *action)
 
virtual void viewBoundingBox (const SbBox3f &box, float aspect, float slack)=0
 
- Public Member Functions inherited from SoNode
void setOverride (const SbBool state)
 
SbBool isOverride (void) const
 
void setNodeType (const NodeType type)
 
NodeType getNodeType (void) const
 
virtual SoNodecopy (SbBool copyconnections=FALSE) const
 
virtual SbBool affectsState (void) const
 
virtual void GLRenderBelowPath (SoGLRenderAction *action)
 
virtual void GLRenderInPath (SoGLRenderAction *action)
 
virtual void GLRenderOffPath (SoGLRenderAction *action)
 
virtual void pick (SoPickAction *action)
 
virtual void search (SoSearchAction *action)
 
virtual void write (SoWriteAction *action)
 
virtual void grabEventsSetup (void)
 
virtual void grabEventsCleanup (void)
 
virtual void startNotify (void)
 
virtual void notify (SoNotList *l)
 
SbUniqueId getNodeId (void) const
 
virtual SoChildListgetChildren (void) const
 
virtual void writeInstance (SoOutput *out)
 
virtual SoNodeaddToCopyDict (void) const
 
virtual void copyContents (const SoFieldContainer *from, SbBool copyconnections)
 
virtual SoFieldContainercopyThroughConnection (void) const
 
- Public Member Functions inherited from SoFieldContainer
void setToDefaults (void)
 
SbBool hasDefaultValues (void) const
 
SbBool fieldsAreEqual (const SoFieldContainer *container) const
 
void copyFieldValues (const SoFieldContainer *container, SbBool copyconnections=FALSE)
 
SbBool set (const char *const fielddata)
 
void get (SbString &fielddata)
 
virtual int getFields (SoFieldList &l) const
 
virtual int getAllFields (SoFieldList &l) const
 
virtual SoFieldgetField (const SbName &name) const
 
virtual SoFieldgetEventIn (const SbName &name) const
 
virtual SoFieldgetEventOut (const SbName &name) const
 
SbBool getFieldName (const SoField *const field, SbName &name) const
 
SbBool enableNotify (const SbBool flag)
 
SbBool isNotifyEnabled (void) const
 
SbBool set (const char *fielddata, SoInput *input)
 
void get (SbString &fielddata, SoOutput *out)
 
virtual SbBool validateNewFieldValue (SoField *field, void *newval)
 
virtual void addWriteReference (SoOutput *out, SbBool isfromfield=FALSE)
 
SbBool getIsBuiltIn (void) const
 
virtual void getFieldsMemorySize (size_t &managed, size_t &unmanaged) const
 
void setUserData (void *userdata) const
 
void * getUserData (void) const
 
- Public Member Functions inherited from SoBase
void ref (void) const
 
void unref (void) const
 
void unrefNoDelete (void) const
 
int32_t getRefCount (void) const
 
void touch (void)
 
SbBool isOfType (SoType type) const
 Returns TRUE if the type of this object is either of the same type or inherited from type. More...
 
virtual SbName getName (void) const
 
virtual void setName (const SbName &newname)
 
void addAuditor (void *const auditor, const SoNotRec::Type type)
 
void removeAuditor (void *const auditor, const SoNotRec::Type type)
 
const SoAuditorListgetAuditors (void) const
 
SbBool shouldWrite (void)
 
void assertAlive (void) const
 

Static Public Member Functions

static SoType getClassTypeId (void)
 
static void initClass (void)
 
- Static Public Member Functions inherited from SoNode
static uint32_t getCompatibilityTypes (const SoType &nodetype)
 
static SoType getClassTypeId (void)
 
static SoNodegetByName (const SbName &name)
 
static int getByName (const SbName &name, SoNodeList &l)
 
static void initClass (void)
 
static void initClasses (void)
 
static SbUniqueId getNextNodeId (void)
 
static int getActionMethodIndex (const SoType type)
 
static void getBoundingBoxS (SoAction *action, SoNode *node)
 
static void GLRenderS (SoAction *action, SoNode *node)
 
static void callbackS (SoAction *action, SoNode *node)
 
static void getMatrixS (SoAction *action, SoNode *node)
 
static void handleEventS (SoAction *action, SoNode *node)
 
static void pickS (SoAction *action, SoNode *node)
 
static void rayPickS (SoAction *action, SoNode *node)
 
static void searchS (SoAction *action, SoNode *node)
 
static void writeS (SoAction *action, SoNode *node)
 
static void audioRenderS (SoAction *action, SoNode *node)
 
static void getPrimitiveCountS (SoAction *action, SoNode *node)
 
- Static Public Member Functions inherited from SoFieldContainer
static void initClass (void)
 
static SoType getClassTypeId (void)
 
static void cleanupClass (void)
 
static void initCopyDict (void)
 
static void addCopy (const SoFieldContainer *orig, const SoFieldContainer *copy)
 
static SoFieldContainercheckCopy (const SoFieldContainer *orig)
 
static SoFieldContainerfindCopy (const SoFieldContainer *orig, const SbBool copyconnections)
 
static void copyDone (void)
 
- Static Public Member Functions inherited from SoBase
static void initClass (void)
 Sets up initialization for data common to all instances of this class, like submitting necessary information to the Coin type system.
 
static SoType getClassTypeId (void)
 This static method returns the SoType object associated with objects of this class.
 
static void addName (SoBase *const base, const char *const name)
 
static void removeName (SoBase *const base, const char *const name)
 
static void incrementCurrentWriteCounter (void)
 
static void decrementCurrentWriteCounter (void)
 
static SoBasegetNamedBase (const SbName &name, SoType type)
 
static int getNamedBases (const SbName &name, SoBaseList &baselist, SoType type)
 
static SbBool read (SoInput *input, SoBase *&base, SoType expectedtype)
 
static void setInstancePrefix (const SbString &c)
 
static void setTraceRefs (SbBool trace)
 
static SbBool getTraceRefs (void)
 
static SbBool connectRoute (SoInput *input, const SbName &fromnodename, const SbName &fromfieldname, const SbName &tonodename, const SbName &tofieldname)
 
static SbBool readRoute (SoInput *input)
 

Public Attributes

SoSFEnum viewportMapping
 
SoSFVec3f position
 
SoSFRotation orientation
 
SoSFFloat aspectRatio
 
SoSFFloat nearDistance
 
SoSFFloat farDistance
 
SoSFFloat focalDistance
 

Protected Member Functions

virtual const SoFieldDatagetFieldData (void) const
 
 SoCamera (void)
 
virtual ~SoCamera ()
 
virtual void jitter (int numpasses, int curpass, const SbViewportRegion &vpreg, SbVec3f &jitteramount) const
 
- Protected Member Functions inherited from SoNode
 SoNode (void)
 
virtual ~SoNode ()
 
virtual SbBool readInstance (SoInput *in, unsigned short flags)
 
- Protected Member Functions inherited from SoFieldContainer
 SoFieldContainer (void)
 
virtual ~SoFieldContainer ()
 
- Protected Member Functions inherited from SoBase
 SoBase (void)
 
virtual ~SoBase ()
 
virtual void destroy (void)
 
SbBool hasMultipleWriteRefs (void) const
 
SbBool writeHeader (SoOutput *out, SbBool isgroup, SbBool isengine) const
 
void writeFooter (SoOutput *out) const
 
virtual const char * getFileFormatName (void) const
 
virtual SoNotRec createNotRec (void)
 

Static Protected Member Functions

static const SoFieldData ** getFieldDataPtr (void)
 
- Static Protected Member Functions inherited from SoNode
static const SoFieldData ** getFieldDataPtr (void)
 
static void setNextActionMethodIndex (int index)
 
static int getNextActionMethodIndex (void)
 
static void incNextActionMethodIndex (void)
 
static void setCompatibilityTypes (const SoType &nodetype, const uint32_t bitmask)
 
- Static Protected Member Functions inherited from SoBase
static uint32_t getCurrentWriteCounter (void)
 
static void staticDataLock (void)
 
static void staticDataUnlock (void)
 

Additional Inherited Members

- Protected Types inherited from SoBase
enum  BaseFlags { IS_ENGINE = 0x01, IS_GROUP = 0x02 }
 
- Protected Attributes inherited from SoNode
SbUniqueId uniqueId
 
- Protected Attributes inherited from SoFieldContainer
SbBool isBuiltIn
 
- Static Protected Attributes inherited from SoNode
static SbUniqueId nextUniqueId = 1
 
static int nextActionMethodIndex = 0
 

Detailed Description

The SoCamera class is the abstract base class for camera definition nodes.

To be able to view a scene, one needs to have a camera in the scene graph. A camera node will set up the projection and viewing matrices for rendering of the geometry in the scene.

This node just defines the abstract interface by collecting common fields that all camera type nodes needs. Use the non-abstract camera node subclasses within a scene graph. The ones that are default part of the Coin library are SoPerspectiveCamera and SoOrthographicCamera, which uses the two different projections given by their name.

Note that the viewer components of the GUI glue libraries of Coin (SoXt, SoQt, SoWin, etc) will automatically insert a camera into a scene graph if none has been defined.

It is possible to have more than one camera in a scene graph. One common trick is for instance to use a second camera to display static geometry or overlay geometry (e.g. for head-up displays ("HUD")), as shown by this example code:

#include <Inventor/Qt/SoQt.h>
#include <Inventor/Qt/viewers/SoQtExaminerViewer.h>
#include <Inventor/nodes/SoNodes.h>
int
main(int argc, char ** argv)
{
QWidget * mainwin = SoQt::init(argv[0]);
SoSeparator * root = new SoSeparator;
root->ref();
// Adds a camera and a red cone. The first camera found in the
// scene graph by the SoQtExaminerViewer will be picked up and
// initialized automatically.
SoMaterial * material = new SoMaterial;
material->diffuseColor.setValue(1.0, 0.0, 0.0);
root->addChild(material);
root->addChild(new SoCone);
// Set up a second camera for the remaining geometry. This camera
// will not be picked up and influenced by the viewer, so the
// geometry will be kept static.
pcam->position = SbVec3f(0, 0, 5);
pcam->nearDistance = 0.1;
pcam->farDistance = 10;
root->addChild(pcam);
// Adds a green cone to demonstrate static geometry.
SoMaterial * greenmaterial = new SoMaterial;
greenmaterial->diffuseColor.setValue(0, 1.0, 0.0);
root->addChild(greenmaterial);
root->addChild(new SoCone);
SoQtExaminerViewer * viewer = new SoQtExaminerViewer(mainwin);
viewer->setSceneGraph(root);
viewer->show();
SoQt::show(mainwin);
SoQt::mainLoop();
delete viewer;
root->unref();
return 0;
}

NB: The support for multiple cameras in Coin is limited, and problems with multiple cameras will be considered fixed on a case by case basis.

Member Enumeration Documentation

◆ ViewportMapping

Enumerates the available possibilities for how the render frame should map the viewport.

◆ StereoMode

Enumerates the possible stereo modes.

Enumerator
MONOSCOPIC 

No stereo.

LEFT_VIEW 

Left view.

RIGHT_VIEW 

Right view.

Constructor & Destructor Documentation

◆ SoCamera()

SoCamera::SoCamera ( void  )
protected

Constructor.

◆ ~SoCamera()

SoCamera::~SoCamera ( )
protectedvirtual

Destructor.

Member Function Documentation

◆ getTypeId()

SoType SoCamera::getTypeId ( void  ) const
virtual

Returns the type identification of an object derived from a class inheriting SoBase. This is used for runtime type checking and "downward" casting.

Usage example:

void foo(SoNode * node)
{
if (node->getTypeId() == SoFile::getClassTypeId()) {
SoFile * filenode = (SoFile *)node; // safe downward cast, knows the type
}
}

For application programmers wanting to extend the library with new nodes, engines, nodekits, draggers or others: this method needs to be overridden in all subclasses. This is typically done as part of setting up the full type system for extension classes, which is usually accomplished by using the predefined macros available through for instance Inventor/nodes/SoSubNode.h (SO_NODE_INIT_CLASS and SO_NODE_CONSTRUCTOR for node classes), Inventor/engines/SoSubEngine.h (for engine classes) and so on.

For more information on writing Coin extensions, see the class documentation of the top level superclasses for the various class groups.

Implements SoBase.

Reimplemented in SoFrustumCamera, SoOrthographicCamera, SoPerspectiveCamera, and SoReversePerspectiveCamera.

◆ getFieldData()

const SoFieldData * SoCamera::getFieldData ( void  ) const
protectedvirtual

Returns a pointer to the class-wide field data storage object for this instance. If no fields are present, returns NULL.

Reimplemented from SoFieldContainer.

Reimplemented in SoFrustumCamera, SoOrthographicCamera, SoPerspectiveCamera, and SoReversePerspectiveCamera.

◆ getViewVolume() [1/2]

SbViewVolume SoCamera::getViewVolume ( const SbViewportRegion vp,
SbViewportRegion resultvp,
const SbMatrix mm = SbMatrix::identity() 
) const

Convenience method which returns the actual view volume used when rendering, adjusted for the current viewport mapping.

Supply the view's viewport in vp. If the viewport mapping is one of CROP_VIEWPORT_FILL_FRAME, CROP_VIEWPORT_LINE_FRAME or CROP_VIEWPORT_NO_FRAME, resultvp will be modified to contain the resulting viewport.

If you got any transformations in front of the camera, mm should contain this transformation.

Since
Coin 4.0

◆ pointAt() [1/2]

void SoCamera::pointAt ( const SbVec3f targetpoint)

Reorients the camera so that it points towards targetpoint. The positive Y-axis is used as the up vector of the camera, unless the new camera direction is parallel to this axis, in which case the positive Z-axis will be used instead.

◆ pointAt() [2/2]

void SoCamera::pointAt ( const SbVec3f targetpoint,
const SbVec3f upvector 
)

Reorients the camera so that it points towards targetpoint, using upvector as the camera up vector.

This function is an extension for Coin, and it is not available in the original SGI Open Inventor v2.1 API.

◆ scaleHeight()

void SoCamera::scaleHeight ( float  scalefactor)
pure virtual

Sets a scalefactor for the height of the camera viewport. What "viewport height" means exactly in this context depends on the camera model. See documentation in subclasses.

Implemented in SoFrustumCamera, SoOrthographicCamera, and SoPerspectiveCamera.

◆ getViewVolume() [2/2]

SbViewVolume SoCamera::getViewVolume ( float  useaspectratio = 0.0f) const
pure virtual

Returns total view volume covered by the camera under the current settings.

This view volume is not adjusted to account for viewport mapping. If you want the same view volume as the one used during rendering, you should use getViewVolume(SbViewportRegion & vp, const SbMatrix & mm), or do something like this:

SbViewVolume vv;
float aspectratio = myviewport.getViewportAspectRatio();

switch (camera->viewportMapping.getValue()) {
case SoCamera::CROP_VIEWPORT_FILL_FRAME:
case SoCamera::CROP_VIEWPORT_LINE_FRAME:
case SoCamera::CROP_VIEWPORT_NO_FRAME:
  vv = camera->getViewVolume(0.0f);
  break;
case SoCamera::ADJUST_CAMERA:
  vv = camera->getViewVolume(aspectratio);
  if (aspectratio < 1.0f) vv.scale(1.0f / aspectratio);
  break;
case SoCamera::LEAVE_ALONE:
  vv = camera->getViewVolume(0.0f);
  break;
default:
  assert(0 && "unknown viewport mapping");
  break;
}

Also, for the CROPPED viewport mappings, the viewport might be changed if the viewport aspect ratio is not equal to the camera aspect ratio. See the SoCamera::getView() source-code (private method) to see how this is done.

Implemented in SoFrustumCamera, SoOrthographicCamera, and SoPerspectiveCamera.

◆ viewAll() [1/2]

void SoCamera::viewAll ( SoNode *const  sceneroot,
const SbViewportRegion vpregion,
const float  slack = 1.0f 
)

Position the camera so that all geometry of the scene from sceneroot is contained in the view volume of the camera, while keeping the camera orientation constant.

Finds the bounding box of the scene and calls SoCamera::viewBoundingBox(). A bounding sphere will be calculated from the scene bounding box, so the camera will "view all" even when the scene is rotated, in any way.

The slack argument gives a multiplication factor to the distance the camera is supposed to move out from the sceneroot mid-point.

A value less than 1.0 for the slack argument will therefore cause the camera to come closer to the scene, a value of 1.0 will position the camera as exactly outside the scene bounding sphere, and a value larger than 1.0 will give "extra slack" versus the scene bounding sphere.

◆ viewAll() [2/2]

void SoCamera::viewAll ( SoPath *const  path,
const SbViewportRegion vpregion,
const float  slack = 1.0f 
)

Position the camera so all geometry of the scene in path is contained in the view volume of the camera.

Finds the bounding box of the scene and calls SoCamera::viewBoundingBox().

◆ getViewportBounds()

SbViewportRegion SoCamera::getViewportBounds ( const SbViewportRegion region) const

Based in the SoCamera::viewportMapping setting, convert the values of region to the viewport region we will actually render into.

◆ setStereoMode()

void SoCamera::setStereoMode ( StereoMode  mode)

Sets the stereo mode.

◆ getStereoMode()

SoCamera::StereoMode SoCamera::getStereoMode ( void  ) const

Returns the stereo mode.

◆ setStereoAdjustment()

void SoCamera::setStereoAdjustment ( float  adjustment)

Sets the stereo adjustment. This is the distance between the left and right "eye" when doing stereo rendering.

When doing stereo rendering, Coin will render two views, one for the left eye, and one for the right eye. The stereo adjustment is, a bit simplified, how much the camera is translated along the local X-axis between the left and the right view.

The default distance is 0.1, which is chosen since it is the approximate distance between the human eyes.

To create a nice looking and visible stereo effect, the application programmer will often have to adjust this value. If all you want to do is examine simple standalone 3D objects, it is possible to calculate a stereo offset based on the bounding box of the 3D model (or scale the model down to an appropriate size).

However, if you have a large scene, where you want to fly around in the scene, and see stereo on different objects as you approach them, you can't calculate the stereo offset based on the bounding box of the scene, but rather use a stereo offset based on the scale of the individual objects/details you want to examine.

Please note that it is important to set a sensible focal distance when doing stereo rendering. See setBalanceAdjustment() for information about how the focal distance affects the stereo rendering.

See also
setBalanceAdjustment()

◆ getStereoAdjustment()

float SoCamera::getStereoAdjustment ( void  ) const

Returns the stereo adjustment.

See also
setStereoAdjustment()

◆ setBalanceAdjustment()

void SoCamera::setBalanceAdjustment ( float  adjustment)

Sets the stereo balance adjustment. This is a factor that enables you to move the zero parallax plane. Geometry in front of the zero parallax plane will appear to be in front of the screen.

The balance adjustment is multiplied with the focal distance to find the zero parallax plane. The default value is 1.0, and the zero parallax plane is then at the focal point.

See also
SoCamera::focalDistance

◆ getBalanceAdjustment()

float SoCamera::getBalanceAdjustment ( void  ) const

Returns the stereo balance adjustment.

See also
setBalanceAdjustment()

◆ doAction()

void SoCamera::doAction ( SoAction action)
virtual

This function performs the typical operation of a node for any action.

Reimplemented from SoNode.

◆ callback()

void SoCamera::callback ( SoCallbackAction action)
virtual

Action method for SoCallbackAction.

Simply updates the state according to how the node behaves for the render action, so the application programmer can use the SoCallbackAction for extracting information about the scene graph.

Reimplemented from SoNode.

◆ GLRender()

void SoCamera::GLRender ( SoGLRenderAction action)
virtual

Action method for the SoGLRenderAction.

This is called during rendering traversals. Nodes influencing the rendering state in any way or want to throw geometry primitives at OpenGL override this method.

Reimplemented from SoNode.

◆ audioRender()

void SoCamera::audioRender ( SoAudioRenderAction action)
virtual

Action method for SoAudioRenderAction.

Does common processing for SoAudioRenderAction action instances.

Reimplemented from SoNode.

◆ getBoundingBox()

void SoCamera::getBoundingBox ( SoGetBoundingBoxAction action)
virtual

Action method for the SoGetBoundingBoxAction.

Calculates bounding box and center coordinates for node and modifies the values of the action to encompass the bounding box for this node and to shift the center point for the scene more towards the one for this node.

Nodes influencing how geometry nodes calculate their bounding box also override this method to change the relevant state variables.

Reimplemented from SoNode.

◆ getMatrix()

void SoCamera::getMatrix ( SoGetMatrixAction action)
virtual

Action method for SoGetMatrixAction.

Updates action by accumulating with the transformation matrix of this node (if any).

Reimplemented from SoNode.

◆ handleEvent()

void SoCamera::handleEvent ( SoHandleEventAction action)
virtual

Picking actions can be triggered during handle event action traversal, and to do picking we need to know the camera state.

See also
SoCamera::rayPick()

Reimplemented from SoNode.

◆ rayPick()

void SoCamera::rayPick ( SoRayPickAction action)
virtual

Action method for SoRayPickAction.

Checks the ray specification of the action and tests for intersection with the data of the node.

Nodes influencing relevant state variables for how picking is done also override this method.

Reimplemented from SoNode.

◆ getPrimitiveCount()

void SoCamera::getPrimitiveCount ( SoGetPrimitiveCountAction action)
virtual

Action method for the SoGetPrimitiveCountAction.

Calculates the number of triangle, line segment and point primitives for the node and adds these to the counters of the action.

Nodes influencing how geometry nodes calculate their primitive count also override this method to change the relevant state variables.

Reimplemented from SoNode.

◆ viewBoundingBox()

void SoCamera::viewBoundingBox ( const SbBox3f box,
float  aspect,
float  slack 
)
pure virtual

Convenience method for setting up the camera definition to cover the given bounding box with the given aspect ratio. Multiplies the exact dimensions with a slack factor to have some space between the rendered model and the borders of the rendering area.

If you define your own camera node class, be aware that this method should not set the orientation field of the camera, only the position, focal distance and near and far clipping planes.

Implemented in SoFrustumCamera, SoOrthographicCamera, and SoPerspectiveCamera.

◆ jitter()

void SoCamera::jitter ( int  numpasses,
int  curpass,
const SbViewportRegion vpreg,
SbVec3f jitteramount 
) const
protectedvirtual

"Jitter" the camera according to the current rendering pass (curpass), to get an antialiased rendering of the scene when doing multipass rendering.

Member Data Documentation

◆ viewportMapping

SoSFEnum SoCamera::viewportMapping

Set up how the render frame should map the viewport. The default is SoCamera::ADJUST_CAMERA.

◆ position

SoSFVec3f SoCamera::position

Camera position. Defaults to <0,0,1>.

◆ orientation

SoSFRotation SoCamera::orientation

Camera orientation specified as a rotation value from the default orientation where the camera is pointing along the negative Z-axis, with "up" along the positive Y-axis.

E.g., to rotate the camera to point along the X-axis:

mycamera->orientation.setValue(SbRotation(SbVec3f(0, 1, 0), M_PI / 2.0f));

For queries, e.g. to get the current "up" and "look at" vectors of the camera:

SbRotation camrot = mycamera->orientation.getValue();
SbVec3f upvec(0, 1, 0); // init to default up vector
camrot.multVec(upvec, upvec);
SbVec3f lookat(0, 0, -1); // init to default view direction vector
camrot.multVec(lookat, lookat);

◆ aspectRatio

SoSFFloat SoCamera::aspectRatio

Aspect ratio for the camera (i.e. width / height). Defaults to 1.0.

◆ nearDistance

SoSFFloat SoCamera::nearDistance

Distance from camera position to the near clipping plane in the camera's view volume.

Default value is 1.0. Value must be larger than 0.0, or it will not be possible to construct a valid viewing volume (for perspective rendering, at least).

If you use one of the viewer components from the So[Xt|Qt|Win|Gtk] GUI libraries provided Kongsberg Oil & Gas Technologies, they will automatically update this value for the scene camera according to the scene bounding box. Ditto for the far clipping plane.

See also
SoCamera::farDistance

◆ farDistance

SoSFFloat SoCamera::farDistance

Distance from camera position to the far clipping plane in the camera's view volume.

Default value is 10.0. Must be larger than the SoCamera::nearDistance value, or it will not be possible to construct a valid viewing volume.

Note that the range [nearDistance, farDistance] decides the dynamic range of the z-buffer in the underlying polygon-rendering rasterizer. What this means is that if the near and far clipping planes of the camera are wide apart, the possibility of visual artifacts will increase. The artifacts will manifest themselves in the form of flickering of primitives close in depth.

It is therefore a good idea to keep the near and far clipping planes of your camera(s) as closely fitted around the geometry of the scene graph as possible.

See also
SoCamera::nearDistance, SoPolygonOffset

◆ focalDistance

SoSFFloat SoCamera::focalDistance

Distance from camera position to center of scene.


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