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SoMultiDataSeparator Class

Separator for combining multiple data sets.

Inheritance Hierarchy

Namespace: OIV.LDM.Nodes
Assembly: OIV.LDM (in OIV.LDM.dll) Version: 2024.2.1.0 (10.16.1.0)
Syntax
public class SoMultiDataSeparator : SoSeparator

The SoMultiDataSeparator type exposes the following members.

Constructors
  NameDescription
Public methodSoMultiDataSeparator

Constructor.

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Methods
  NameDescription
Public methodAddChild

Adds a child as last one in group.

(Inherited from SoGroup.)
Public methodAffectsState

Returns true if a node has an effect on the state during traversal.

(Inherited from SoSeparator.)
Public methodCallback
(Inherited from SoSeparator.)
Public methodClearCacheList
(Inherited from SoSeparator.)
Public methodCopy
Calls Copy(false).
(Inherited from SoNode.)
Public methodCopy(Boolean)

Creates and returns an exact copy of the node.

(Inherited from SoNode.)
Public methodCopyFieldValues(SoFieldContainer)
Calls CopyFieldValues(fc, false).
(Inherited from SoFieldContainer.)
Public methodCopyFieldValues(SoFieldContainer, Boolean)

Copies the contents of fc's fields into this object's fields.

(Inherited from SoFieldContainer.)
Public methodDispose
Releases all resources used by SoDisposable.
(Inherited from SoDisposable.)
Public methodDistribute
(Inherited from SoNode.)
Public methodDoAction
Public methodEnableNotify

Notification at this Field Container is enabled (if flag == true) or disabled (if flag == false).

(Inherited from SoFieldContainer.)
Public methodEquals
Determines whether the specified Object is equal to the current Object.
(Inherited from Object.)
Public methodFieldsAreEqual

Returns true if this object's fields are exactly equal to fc's fields.

(Inherited from SoFieldContainer.)
Public methodFindChild

Finds index of given child within group.

(Inherited from SoGroup.)
Public methodGet

Returns the values of the fields of this object in the Open Inventor ASCII file format in the given string.

(Inherited from SoFieldContainer.)
Public methodGetAllFields

Returns a list of fields, including the eventIn's and eventOut's.

(Inherited from SoFieldContainer.)
Public methodGetAlternateRep

This method is called by actions to allow the node to provide an "alternate representation" when appropriate (typically depending on the action type).

(Inherited from SoNode.)
Public methodGetBoundingBox
Public methodGetChild

Returns pointer the child node with the given index.

(Inherited from SoGroup.)
Public methodGetEventIn

Returns a the eventIn with the given name.

(Inherited from SoFieldContainer.)
Public methodGetEventOut

Returns the eventOut with the given name.

(Inherited from SoFieldContainer.)
Public methodGetField

Returns a the field of this object whose name is fieldName.

(Inherited from SoFieldContainer.)
Public methodGetFieldName

Returns the name of the given field in the fieldName argument.

(Inherited from SoFieldContainer.)
Public methodGetFields

Appends references to all of this object's fields to resultList, and returns the number of fields appended.

(Inherited from SoFieldContainer.)
Public methodGetHashCode
Overrides GetHashCode().
(Inherited from SoNetBase.)
Public methodGetMatrix
(Inherited from SoSeparator.)
Public methodGetName

Returns the name of an instance.

(Inherited from SoBase.)
Public methodGetNumChildren

Returns number of children.

(Inherited from SoGroup.)
Public methodGetPrimitiveCount
(Inherited from SoSeparator.)
Public methodGetRenderEngineMode

Returns the supported Render engine mode.

(Inherited from SoNode.)
Public methodGetRenderUnitID
(Inherited from SoNode.)
Public methodGetStringName (Inherited from SoBase.)
Public methodGetType
Gets the Type of the current instance.
(Inherited from Object.)
Public methodGLRender
Public methodGLRenderBelowPath
Public methodGLRenderInPath
Public methodGLRenderOffPath
Public methodGrabEventsCleanup
(Inherited from SoNode.)
Public methodGrabEventsSetup
(Inherited from SoNode.)
Public methodHandleEvent
(Inherited from SoSeparator.)
Public methodHasDefaultValues

Returns true if all of the object's fields have their default values.

(Inherited from SoFieldContainer.)
Public methodInsertChild

Adds a child so that it becomes the one with the given index.

(Inherited from SoGroup.)
Public methodIsBoundingBoxIgnoring

Used by BoundingBoxAction to known if bounding box computation should be ignored or not.

(Inherited from SoGroup.)
Public methodIsNotifyEnabled

Notification is the process of telling interested objects that this object has changed.

(Inherited from SoFieldContainer.)
Public methodIsOverride

Returns the state of the override flag.

(Inherited from SoNode.)
Public methodIsSynchronizable

Gets the ScaleViz synchronizable state of this object.

(Inherited from SoBase.)
Public methodPick
(Inherited from SoGroup.)
Public methodRayPick
(Inherited from SoSeparator.)
Public methodRemoveAllChildren

Removes all children from group.

(Inherited from SoGroup.)
Public methodRemoveChild(Int32)

Removes child with given index from group.

(Inherited from SoGroup.)
Public methodRemoveChild(SoNode)

Removes first instance of given child from group.

(Inherited from SoGroup.)
Public methodReplaceChild(Int32, SoNode)

Replaces child with given index with new child.

(Inherited from SoGroup.)
Public methodReplaceChild(SoNode, SoNode)

Replaces first instance of given child with new child.

(Inherited from SoGroup.)
Public methodSearch
(Inherited from SoSeparator.)
Public methodSet

Sets one or more fields in this object to the values specified in the given string, which should be a string in the Open Inventor file format.

(Inherited from SoFieldContainer.)
Public methodSetName (Inherited from SoBase.)
Public methodSetOverride

Turns the override flag on or off.

(Inherited from SoNode.)
Public methodSetSynchronizable

Sets this to be a ScaleViz synchronizable object.

(Inherited from SoBase.)
Public methodSetToDefaults

Sets all fields in this object to their default values.

(Inherited from SoFieldContainer.)
Public methodToString
Converts this SoBase structure to a human readable string.
(Inherited from SoBase.)
Public methodTouch

Marks an instance as modified, simulating a change to it.

(Inherited from SoNode.)
Public methodWrite
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Properties
  NameDescription
Public propertyboundingBoxCaching
(Inherited from SoSeparator.)
Public propertyboundingBoxIgnoring

Whether to ignore this node during bounding box traversal.

(Inherited from SoGroup.)
Public propertyfastEditing

Specifies the fast edit mode of the separator node.

(Inherited from SoSeparator.)
Public propertyIsDisposable
ISafeDisposable interface implementation.
(Inherited from SoDisposable.)
Public propertypickCulling

Whether to cull during picking traversal.

(Inherited from SoSeparator.)
Public propertyrenderCaching Obsolete.

Whether to cache during rendering traversal.

(Inherited from SoSeparator.)
Public propertyrenderCulling

Whether to cull during rendering traversal.

(Inherited from SoSeparator.)
Public propertyrenderUnitId

Used during the ScaleViz depth compositing process, this field specifies which render unit (OIRU) will render the sub scene graph below this separator.

(Inherited from SoSeparator.)
Public propertyUserData
Gets or sets the user data to be contained by the field container.
(Inherited from SoFieldContainer.)
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Remarks

The OIV.LDM.Nodes.SoMultiDataSeparator node allows you to combine multiple data sets.

This is the correct method for combining multiple data sets. Combining multiple data sets without inserting them under an OIV.LDM.Nodes.SoMultiDataSeparator node may produce incorrect results and should be avoided.

Each data set is represented by an OIV.LDM.Nodes.SoDataSet node (typically an OIV.VolumeViz.Nodes.SoVolumeData node). Combining is enabled by an OIV.LDM.Nodes.SoDataCompositor node for CPU combining or an OIV.VolumeViz.Nodes.SoVolumeShader node for GPU combining. A common use of GPU combining is to implement co-blending of multiple volumes, in other words using a fragment shader to combine the color and/or intensity values of the voxels.

Some rules must be followed when doing render or data compositing:

GPU combining must be implemented in a shader program written in the standard GLSL language. The shader program will be specified using an OIV.VolumeViz.Nodes.SoVolumeShader node. The shader source code is loaded using (for example) an OIV.Inventor.Nodes.SoFragmentShader object. Uniform parameters for the shader may be specified using the subclasses of OIV.Inventor.Nodes.SoShaderParameter. See OIV.VolumeViz.Nodes.SoVolumeShader for more information about the shader function library provided by VolumeViz.

It is possible to compose datasets that have different dimensions, tile sizes and transformations. In order to help fetch the correct data values in custom shaders, texture coordinates conversion functions are provided in the VolumeViz/vvizStructure.h shader include. See OIV.VolumeViz.Nodes.SoVolumeShader for more details.

For each data set there will typically be an OIV.LDM.Nodes.SoDataRange node and an OIV.LDM.Nodes.SoTransferFunction node to define the mapping from data values to color values. For each OIV.VolumeViz.Nodes.SoVolumeData a separate 3D texture will be generated and sent to the GPU. 3D textures can be generated with different precision (8-bit or 12-bit) according to the OIV.LDM.Nodes.SoDataSet.texturePrecision field. The texture unit used for each data set is determined by the OIV.LDM.Nodes.SoDataSet.dataSetId field. All colormaps are aggregated into a single 2D texture.

A custom fragment shader can retrieve the voxel's data value from each 3D texture using the GLSL VolumeViz function:

VVIZ_DATATYPE value = VVizGetData( dataSetId, texCoord );
A custom fragment shader can lookup the color/intensity for each data value from the appropriate colormap, using the GLSL VolumeViz function:
vec4 color = VVizTransferFunction( value, colorMapId );
A custom fragment shader can then compute (using custom blending functions) the actual color for the voxel and output that color using the GLSL VolumeViz function:
VVizOutputColor( color ):

EXAMPLE

The following code shows how to do multidata rendering using an OIV.VolumeViz.Nodes.SoVolumeShader node to combine values for an OIV.VolumeViz.Nodes.SoVolumeRender node. Given two OIV.VolumeViz.Nodes.SoVolumeData nodes ds1 and ds2:

SoVolumeShader volumeShader = new SoVolumeShader();

SoVolumeData volumeData1 = new SoVolumeData();
volumeData1.dataSetId.Value = 0;
SoDataRange dataRange1 = new SoDataRange();
dataRange1.dataRangeId.Value = 0;
SoTransferFunction colorMap1 = new SoTransferFunction();

SoVolumeData volumeData2 = new SoVolumeData();
volumeData2.dataSetId.Value = 1;
SoDataRange dataRange2 = new SoDataRange();
dataRange2.dataRangeId.Value = 1;
SoTransferFunction colorMap2 = new SoTransferFunction();

SoVolumeRender volumeRender = new SoVolumeRender();

SoMultiDataSeparator multiDataSep = new SoMultiDataSeparator();
   multiDataSep.AddChild( volumeShader ); // Shader to combine volumes

   multiDataSep.AddChild( volumeData1 );
   multiDataSep.AddChild( dataRange1 );
   multiDataSep.AddChild( colorMap1 );

   multiDataSep.AddChild( volumeData2 );
   multiDataSep.AddChild( dataRange2 );
   multiDataSep.AddChild( colorMap2 );

   multiDataSep.AddChild( volumeRender );
root.AddChild(multiDataSep);

See Also