com.openinventor.inventor.geo

Class SoVRMLGeoLOD

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.SoGroup

com.openinventor.inventor.vrmlnodes.SoVRMLParent

com.openinventor.inventor.geo.SoVRMLGeoLOD

All Implemented Interfaces:

SafeDisposable

Deprecated.

As of Open Inventor 9500 See documentation for more details

public class SoVRMLGeoLOD
extends SoVRMLParent

Level-of-detail management for multi-resolution terrains. The SoVRMLGeoLOD node allows applications to build massive tiled, multi-resolution terrain models where the viewer progressively loads higher resolution detail as you fly into the terrain.

VRML X3D SPECIFICATION

This section describes the expected behavior of the node in a conforming X3D / VRML97 browser application. In some cases, the application is responsible for implementing portions of the expected behavior. Open Inventor viewer classes and IVF classes implement some of the application behaviors.

This section may reference portions of the X3D specification that are not present in this help file. The complete X3D spec is available at http://www.web3d.org.

The SoVRMLGeoLOD node provides a terrain-specialized form of the LOD node. It is a grouping node that specifies two different levels of detail for an object using a tree structure, where 0 to 4 children can be specified, and also efficiently manages the loading and unloading of these levels of detail. The level of detail is switched depending upon whether the user is closer or further than range meters from the geospatial coordinate center. The center field should be specified as described in 25.2.4 Specifying geospatial coordinates. The geoOrigin field is used to specify a local coordinate frame for extended precision as described in 25.2.5 Dealing with high-precision coordinates. The geoSystem field is used to define the spatial reference frame and is described in 25.2.3 Specifying a spatial reference frame. When the user is outside the specified range, only the geometry for rootUrl or rootNode are displayed. When the viewer enters the specified range, this geometry is replaced with the contents of the four children files defined by child1Url through child4Url. The four children files are loaded into memory only when the user is within the specified range. Similarly, these are unloaded from memory when the user leaves this range. Figure below illustrates this process. The child URLs shall be arranged in the same order as in the figure; i.e., child1Url represents the bottom-left quadtree child. It is valid to specify less than four child URLs; in which case, the SoVRMLGeoLOD should switch to the children nodes when all of the specified URLs have been loaded. This latter feature can support tree structures other than quadtrees, such as binary trees.

The rootUrl and rootNode fields provide two different ways to specify the geometry of the root tile. You may use one or the other. The rootNode field lets you include the geometry for the root tile directly within the X3D file; whereas the rootUrl field lets you specify a URL for a file that contains the geometry. The result of specifying a value for both of these fields is undefined. The children field is used to expose a portion of the scene graph for the currently loaded set of nodes. The value returned as an event is an MFNode containing the currently selected tile. This will either be the node specified by the rootNode field or the nodes specified by the child1Url, child2Url, child3Url, and child4Url fields. The SoVRMLGeoLOD node shall generate a new children output event each time the scene graph is changed (EXAMPLE whenever nodes are loaded or unloaded). When the new children event is generated, the SoVRMLGeoLOD node shall also generate a level_changed event with value 0 or 1, where 0 indicates the rootNode field and 1 indicates the nodes specified by the child1Url, child2Url, child3Url, and child4Url fields. The SoVRMLGeoLOD node may optionally be implemented with support for a cache of the most recent nodes that have been loaded. This cache should be global across all SoVRMLGeoLOD instances in a scene. This will improve performance when navigating large terrain models by avoiding excessive loading and unloading when a user makes small changes in viewpoint.

File format/default:

VRMLGeoLOD {

metadata	NULL
children	[]
center	0 0 0
child1Url	[]
child2Url	[]
child3Url	[]
child4Url	[]
geoOrigin	NULL
geoSystem	["GD","WE"]
range	10
rootUrl	[]
rootNode	[]
bboxCenter	0 0 0
bboxSize	-1 -1 -1

}

Action behavior:

SoGLRenderAction, SoCallbackAction, SoGetBoundingBoxAction, SoRayPickActionSoGetPrimitiveCountAction

EVENTS

eventIn

SoMFNode	addChildren
SoMFNode	removeChildren
SoMFNode	set_children
SoSFNode	set_metadata

eventOut

SoMFNode	children_changed
SoSFNode	metadata_changed
SoSFNode	level_changed

Deprecated since Open Inventor 9500
The VRML API is no longer supported. See section http://oivdoc95.vsg3d.com/content/compatibility-notes-4#Deprecation of the Reference Manual.

Nested Class Summary

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

Inventor.ConstructorCommand

Field Summary

Fields

Modifier and Type	Field and Description
SoSFVec3d	center Deprecated. Object-space center of the model.
SoMFString	child1Url Deprecated. First child url : bottom-left quadtree child.
SoMFString	child2Url Deprecated. Second child url : up-left quadtree child.
SoMFString	child3Url Deprecated. Third child url : up-right quadtree child.
SoMFString	child4Url Deprecated. Fourth child url : bottom-right quadtree child.
SoSFNode	geoOrigin Deprecated. An SoVRMLGeoOrigin node specifying the origin of the local coordinate system.
SoMFString	geoSystem Deprecated. Defines the spatial reference frame.
SoSFFloat	range Deprecated. World-space distance to use as switching criteria.
SoMFNode	rootNode Deprecated. The root tile of the hierarchy.
SoMFString	rootUrl Deprecated. Url of the file that contains the root tile geometry.

Fields inherited from class com.openinventor.inventor.vrmlnodes.SoVRMLParent

bboxCenter, bboxSize, children, metadata

Fields inherited from class com.openinventor.inventor.nodes.SoGroup

boundingBoxIgnoring

Fields inherited from class com.openinventor.inventor.Inventor

VERBOSE_LEVEL, ZeroHandle

Constructor Summary

Constructors

Constructor and Description
SoVRMLGeoLOD() Deprecated. Constructor.
SoVRMLGeoLOD(int nChildren) Deprecated. Constructor that takes approximate number of levels/children.

Method Summary

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

addChild, findChild, getChild, getNumChildren, insertChild, removeAllChildren, removeChild, removeChild, replaceChild, replaceChild

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

affectsState, callback, copy, copy, distribute, doAction, getAlternateRep, getBoundingBox, getByName, getMatrix, getPrimitiveCount, 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, getEXTERNPROTO, getName, getPROTO, isDisposable, isSynchronizable, setName, setSynchronizable

Methods inherited from class com.openinventor.inventor.Inventor

getAddress, getNativeResourceHandle, startInternalThreads, stopInternalThreads

Methods inherited from class java.lang.Object

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

Field Detail

geoSystem

public final SoMFString geoSystem

Deprecated.

Defines the spatial reference frame.
Valid values are:

• GC: Earth-fixed Geocentric with respect to the WGS84 ellipsoid.
• GD: Geodetic spatial reference frame.
  An optional second string may be used to specify the ellipsoid using one of the ellipsoid codes that are defined in X3D. If no ellipsoid is specified, then "WE" is assumed (the WGS84 ellipsoid).
• UTM: Universal Transverse Mercator
  One further required argument must be supplied for UTM in order to specify the zone number (1..60). This is given in the form "Z<n>", where "<n>" is the zone number. An optional argument of "S" may be supplied in order to specify that the coordinates are in the southern hemisphere (otherwise, northern hemisphere will be assumed).

child1Url

public final SoMFString child1Url

Deprecated.

First child url : bottom-left quadtree child.

child2Url

public final SoMFString child2Url

Deprecated.

Second child url : up-left quadtree child.

child3Url

public final SoMFString child3Url

Deprecated.

Third child url : up-right quadtree child.

child4Url

public final SoMFString child4Url

Deprecated.

Fourth child url : bottom-right quadtree child.

rootUrl

public final SoMFString rootUrl

Deprecated.

Url of the file that contains the root tile geometry.

range

public final SoSFFloat range

Deprecated.

World-space distance to use as switching criteria.

center

public final SoSFVec3d center

Deprecated.

Object-space center of the model.

geoOrigin

public final SoSFNode geoOrigin

Deprecated.

An SoVRMLGeoOrigin node specifying the origin of the local coordinate system.

rootNode

public final SoMFNode rootNode

Deprecated.

The root tile of the hierarchy.

Constructor Detail

SoVRMLGeoLOD

public SoVRMLGeoLOD()

Deprecated.

Constructor.

SoVRMLGeoLOD

public SoVRMLGeoLOD(int nChildren)

Deprecated.

Constructor that takes approximate number of levels/children.