com.openinventor.ldm

Class SoLDMTopoOctree

java.lang.Object

com.openinventor.inventor.Inventor

com.openinventor.ldm.SoLDMTopoOctree

public class SoLDMTopoOctree
extends Inventor

Octree topology queries. The SoLDMTopoOctree class provides information about the hierarchy of LDM tiles used for a given dataset, which depends only on the dataset dimensions and the tile dimensions.

For example, an application can query the total number of LDM tiles in a data set, the number of resolution levels in the LDM tile hierarchy, the id of the tile that contains a specified voxel position, the position and extent of a specified tile id, and more. An application can conveniently query the SoLDMTopoOctree for an actual data set using the SoDataSet.getLDMTopoOctree() method or create an LDMTopoOctree object with any specified dimensions. In the latter case, the LDMTopoOctree must be initialized using the init() method.

In VolumeViz LDM every tile has both a tileID and a fileID. The tileID is the unique identifier of a tile in the (conceptual) complete, symmetrical hierarchy. The fileID is the index of a tile in a sequential numbering of all the tiles that actually contain data. The tileID is normally used to identify tiles in an application, but the fileID is used, for example, when calling the readTile method in an SoVolumeReader class. In a cubical volume (all three dimensions the same), there are equal numbers of tileIDs and fileIDs, but in most volumes there are many fewer fileIDs than tileIDs.

The terms 'resolution' and 'level' are both used in this class to identify a specific level in the LDM tile hierarchy.

• Resolution level is counted up from the bottom.
  So resolution level 0 is the full resolution tiles. The getTileID() method takes resolution level as a parameter.
• Tile level is counted down from the top.
  So tile level 0 is the lowest resolution tile (tile 0) at the top of the hierarchy. The level() method returns the tile level, not the resolution level.
• Conversion: tileLevel = getLevelMax() - resolutionLevel.

See also:

SoLDMTileID

Nested Class Summary

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

Inventor.ConstructorCommand

Field Summary

Fields inherited from class com.openinventor.inventor.Inventor

VERBOSE_LEVEL, ZeroHandle

Constructor Summary

Constructors

Constructor and Description
SoLDMTopoOctree() Constructor.

Method Summary

Modifier and Type	Method and Description
int	getFileID(SoLDMTileID tileID) Given a tileID, returns the corresponding fileID.
int	getLevelMax() Returns the maximum level of the octree tile hierarchy.
int	getNumFileIDs() Returns the number of fileIDs in the volume.
long	getNumTileIDs() Returns the number of tileIDs in the complete (conceptual) octree.
SoLDMTileID	getTileID(int fileID) Given a fileID, returns the corresponding tileID.
SoLDMTileID	getTileID(SbVec3i32 cellPos, int resolutionLevel) Given the position of a voxel in full resolution voxel coordinates (i,j,k) and a resolution level, returns the tile ID of the corresponding tile.
SbBox3i32	getTilePos(SoLDMTileID tileID) Returns the bounding box, in voxel/cell coordinates, of the specified tile.
SbVec3i32	getTileSize() Return the tilesize used to setup this octree.
void	init(SbVec3i32 dimension, int tileDim) Calls init(dimension, tileDim, (int)0).
void	init(SbVec3i32 dimension, int tileDim, int border) Initialize with the properties of the data set.
boolean	isEmpty() Returns false if the octree is empty.
int	level(long index) Returns the tile level of the given tile Id.
int	level(SoLDMTileID id) Returns the tile level of the given tile Id.

Methods inherited from class com.openinventor.inventor.Inventor

dispose, getNativeResourceHandle

Methods inherited from class java.lang.Object

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

Constructor Detail

SoLDMTopoOctree

public SoLDMTopoOctree()

Constructor.

Method Detail

init

public void init(SbVec3i32 dimension,
                 int tileDim)

Calls init(dimension, tileDim, (int)0).

getTileID

public SoLDMTileID getTileID(int fileID)

Given a fileID, returns the corresponding tileID.

init

public void init(SbVec3i32 dimension,
                 int tileDim,
                 int border)

Initialize with the properties of the data set. Note: Since OIV 9.0, the border parameter is no longer used.

isEmpty

public boolean isEmpty()

Returns false if the octree is empty. Note: Octree must be initialized.

getTilePos

public SbBox3i32 getTilePos(SoLDMTileID tileID)

Returns the bounding box, in voxel/cell coordinates, of the specified tile. Regardless the tile's resolution level in the LDM tile hierarchy, the returned bounding box is always in full-resolution voxel coordinates.

getTileID

public SoLDMTileID getTileID(SbVec3i32 cellPos,
                             int resolutionLevel)

Given the position of a voxel in full resolution voxel coordinates (i,j,k) and a resolution level, returns the tile ID of the corresponding tile. Resolution level is counted up from the bottom of the tile hierarchy, so resolution level 0 is the full resolution tiles.

Regardless of the tile's resolution level in the LDM tile hierarchy, the returned bounding box is always in full-resolution voxel coordinates. In other words, the box is the region of the full-resolution volume that the tile "spans" and the extent of this box is not the same as the tile size unless the specified tile is at resolution level 0 (full resolution).

Example: If the volume is 256 x 256 x 256 with tile size 64

• There are 3 levels of tiles.
• Level 0 / Res 2 : first tile is tileId 0, pos = 0,0,0 x 255,255,255
• Level 1 / Res 1 : first tile is tileId 1, pos = 0,0,0 x 127,127,127
• Level 2 / Res 0 : first tile is tileId 9, pos = 0,0,0 x 63,63,63

getLevelMax

public int getLevelMax()

Returns the maximum level of the octree tile hierarchy. Example: If there are 3 levels in the octree, returns 2. Note: Octree must be initialized.

getTileSize

public SbVec3i32 getTileSize()

Return the tilesize used to setup this octree.

getNumFileIDs

public int getNumFileIDs()

Returns the number of fileIDs in the volume. Effectively this is the total number of actual tiles, including both full resolution and low resolution, required to store the data set. This value is <= getNumTileIDs().

level

public int level(long index)

Returns the tile level of the given tile Id. Conversion: resolutionLevel = getLevelMax() - tileLevel. Note: Octree must be initialized.

getFileID

public int getFileID(SoLDMTileID tileID)

Given a tileID, returns the corresponding fileID.

level

public int level(SoLDMTileID id)

Returns the tile level of the given tile Id. Conversion: resolutionLevel = getLevelMax() - tileLevel. Note: Octree must be initialized.

getNumTileIDs

public long getNumTileIDs()

Returns the number of tileIDs in the complete (conceptual) octree. The complete octree is based on the power-of-2 greater than or equal to the actual volume dimensions. This value is >= getNumFileIDs().