Package com.openinventor.inventor.nodes

Class SoProjection

java.lang.Object

com.openinventor.inventor.Inventor

com.openinventor.inventor.misc.SoBase

com.openinventor.inventor.fields.SoFieldContainer

com.openinventor.inventor.nodes.SoNode

com.openinventor.inventor.nodes.SoProjection

All Implemented Interfaces:

SafeDisposable

Direct Known Subclasses:

SoGeoProjection, SoTransformProjection

public class SoProjection
extends SoNode

Coordinate projection node. This property node defines a coordinate projection that will be applied to all subsequent shapes in the scene graph. Coordinate transform nodes like SoTransform can only apply transforms that can be expressed as a matrix. A coordinate projection can be any algorithm that takes a coordinate and returns a different coordinate. This is particularly useful for geospatial coordinate systems (see SoGeoProjection), but is also useful for using spherical, cylindrical and other coordinate systems directly.

This node works together with projection classes derived from the SbProjection class. The projection classes implement the projection computations applied to 3D points. Applications can create new subclasses of SbProjection.

To use a specific projection, call setProjection() with an instance of the SbProjection class. Each instance of SoProjection can also store a list of projections, each one associated with a unique id. This is convenient for switching between different geospatial projections. Changing the projTypeId value activates the projection registered with the corresponding id.

The default projection is spherical coordinates (SbSphericalProjection).

The projection classes will use the string parameters and float parameters in the fields parameters and floatParameters respectively. See the projection class documentation for relevant parameters.

Normal vectors

• If no normal vectors are given for the geometry (and normal vectors are needed), Open Inventor will automatically compute normal vectors using the projected vertices, i.e. the coordinates after projection has been applied. This is usually the desired result.
• If normal vectors are specified for the geometry, they are not projected. Therefore normal vectors must be specified in post-projection (world) coordinates.

LIMITATIONS

• Shapes
  The following shapes are not supported by SoProjection:
  • Text nodes (SoAnnoText3, SoAsciiText, SoText2, SoText3 )
  • SoCylinder, SoCube, SoCone
  • All classes inheriting from SoAlgebraicShape
  • SoImage
  • NURBS shapes
  • All VolumeViz shapes except
    • SoVolumeRender with some limitations (see SoVolumeRender doc for details)
    • Volume geometry nodes (e.g. SoVolumeIndexedFaceSet)
• Transform nodes
  The projection mechanism is not compatible with transform and manipulator nodes. Using nodes derived from SoTransformation, for example SoTransform or SoTabBoxManip will give unexpected results. To apply a transformation matrix to projected shapes, set the matrix field to the expected value. Shape vertices will be multiplied by the matrix before being projected.
• Draggers
  Because draggers are composed with SoTransformation nodes, they can't be projected using an SoProjection node.
• Memory
  Because shape coordinates must be duplicated, memory consumption will increase when using projections.
• Picking
  Projection is not applied when doing picking (SoRayPickAction). Results may be incorrect.

File format/default:

Projection {

parameters	""
matrix	identity
isOn	true
floatParameters	1
projTypeId	0

}

Action behavior:

Sets: SoCoordinateElement

See Also:

SbProjection, SbSphericalProjection, SoGeoProjection

Nested Class Summary

Nested classes/interfaces inherited from class com.openinventor.inventor.nodes.SoNode

SoNode.RenderModes

Nested classes/interfaces inherited from class com.openinventor.inventor.Inventor

Inventor.ConstructorCommand

Field Summary

Fields

Modifier and Type	Field	Description
SoMFFloat	floatParameters	Float parameters stored for projections.
SoSFBool	isOn	If set to false, projection is inactive.
SoSFMatrix	matrix	Matrix that can be applied before projecting a point.
SoMFString	parameters	String parameters stored for projections.
SoMFString	parametersIn	String parameters stored for projections.
SoSFInt32	projTypeId	Current projection id.

Fields inherited from class com.openinventor.inventor.Inventor

VERBOSE_LEVEL, ZeroHandle

Constructor Summary

Constructors

Constructor	Description
SoProjection()	Constructor.

Method Summary

Modifier and Type	Method	Description
java.lang.String	addProjection(SbProjection projection, int id)	Add a projection with the given name and id to the list.
static SbVec3f[]	checkProjection(SoState state, SoNode node, SbVec3f[] coords)	Apply projection to given coordinates.
SbProjection	getProjection()	Return current projection.
void	setProjection(SbProjection projection)	Set the current projection.

Methods inherited from class com.openinventor.inventor.nodes.SoNode

affectsState, callback, copy, copy, distribute, doAction, getAlternateRep, getBoundingBox, getByName, getMatrix, getPrimitiveCount, getRenderEngineMode, getRenderUnitID, GLRender, GLRenderBelowPath, GLRenderInPath, GLRenderOffPath, grabEventsCleanup, grabEventsSetup, handleEvent, isBoundingBoxIgnoring, isOverride, pick, rayPick, search, setOverride, touch, write

Methods inherited from class com.openinventor.inventor.fields.SoFieldContainer

copyFieldValues, copyFieldValues, enableNotify, fieldsAreEqual, get, getAllFields, getEventIn, getEventOut, getField, getFieldName, hasDefaultValues, isNotifyEnabled, set, setToDefaults

Methods inherited from class com.openinventor.inventor.misc.SoBase

dispose, getName, isDisposable, isSynchronizable, setName, setSynchronizable

Methods inherited from class com.openinventor.inventor.Inventor

getNativeResourceHandle

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

isOn

public final SoSFBool isOn

If set to false, projection is inactive. Default is true.

matrix

public final SoSFMatrix matrix

Matrix that can be applied before projecting a point. Set to Identity by default

projTypeId

public final SoSFInt32 projTypeId

Current projection id. Default is zero.

floatParameters

public final SoMFFloat floatParameters

Float parameters stored for projections.

parameters

public final SoMFString parameters

String parameters stored for projections.

parametersIn

public final SoMFString parametersIn

String parameters stored for projections.

Constructor Detail

SoProjection

public SoProjection()

Constructor.

Method Detail

checkProjection

public static SbVec3f[] checkProjection(SoState state,
                                        SoNode node,
                                        SbVec3f[] coords)

Apply projection to given coordinates. Store projected coordinates in current SoCoordinate3 element.

addProjection

public java.lang.String addProjection(SbProjection projection,
                                      int id)

Add a projection with the given name and id to the list. The projection name is just for convenience. The projection id value should be greater than zero because the default spherical projection already uses this id. If multiple projections are assigned the same id, the first one added to the list will be used.

setProjection

public void setProjection(SbProjection projection)

Set the current projection. The specified projection is used regardless of whether it is in the list. In this case the value of the projTypeId field is not used.

getProjection

public SbProjection getProjection()

Return current projection.