Click or drag to resize
SoVolumeBufferedShape Class

Buffered shape node for volume data.

Inheritance Hierarchy

Namespace: OIV.VolumeViz.Nodes
Assembly: OIV.VolumeViz (in OIV.VolumeViz.dll) Version: 10.12.3.0 (10.12.3.0)
Syntax
public class SoVolumeBufferedShape : SoBufferedShape

The SoVolumeBufferedShape type exposes the following members.

Constructors
  NameDescription
Public methodSoVolumeBufferedShape

Constructor.

Top
Methods
  NameDescription
Public methodAffectsState

Overrides default method on OIV.Inventor.Nodes.SoNode.

(Inherited from SoShape.)
Public methodBeginShape(SoAction, SoShapeTriangleShapes)
Calls BeginShape(action, shapeType, (OIV.Inventor.Details.SoFaceDetail ^)nullptr).
(Inherited from SoShape.)
Public methodBeginShape(SoAction, SoShapeTriangleShapes, SoFaceDetail)

These methods can be used by subclasses to generate triangles more easily when those triangles are part of a larger structure, such as a triangle strip, triangle fan, or triangulated polygon, according to the TriangleShape enumerated type.

(Inherited from SoShape.)
Public methodCallback

Implements primitive generation for all shapes.

(Inherited from SoShape.)
Public methodComputeBBox(SoAction, SbBox3f, SbVec3f)

Computes the AABB bounding box if it must be updated.

(Overrides SoBufferedShapeComputeBBox(SoAction, SbBox3f, SbVec3f).)
Public methodComputeBBox(SoAction, SbXfBox3d, SbVec3d)

Computes the AABB bounding box if it must be updated.

(Overrides SoBufferedShapeComputeBBox(SoAction, SbXfBox3d, SbVec3d).)
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
(Inherited from SoNode.)
Public methodEnableNotify

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

(Inherited from SoFieldContainer.)
Public methodEndShape

end shape previously started with OIV.Inventor.Nodes.SoShape.BeginShape(OIV.Inventor.Actions.SoAction, OIV.Inventor.Nodes.SoShape.TriangleShapes, OIV.Inventor.Details.SoFaceDetail).

(Inherited from SoShape.)
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 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

Manages getBoundingBoxAction action.

(Inherited from SoBufferedShape.)
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 SoNode.)
Public methodGetName

Returns the name of an instance.

(Inherited from SoBase.)
Public methodGetPrimitiveCount

Manages getPrimitiveCount action.

(Inherited from SoBufferedShape.)
Public methodGetRenderEngineMode

Returns the supported Render engine mode.

(Inherited from SoNode.)
Public methodGetRenderUnitID
(Inherited from SoNode.)
Public methodGetShapeType

Gets the current shape Full Scene Antialiasing type.

(Inherited from SoShape.)
Public methodGetStringName (Inherited from SoBase.)
Public methodGetType
Gets the Type of the current instance.
(Inherited from Object.)
Public methodGLRender

Manages GLRender action.

(Overrides SoBufferedShapeGLRender(SoGLRenderAction).)
Public methodGLRenderBelowPath
(Inherited from SoNode.)
Public methodGLRenderInPath
(Inherited from SoNode.)
Public methodGLRenderOffPath
(Inherited from SoNode.)
Public methodGrabEventsCleanup
(Inherited from SoNode.)
Public methodGrabEventsSetup
(Inherited from SoNode.)
Public methodHandleEvent
(Inherited from SoNode.)
Public methodHasDefaultValues

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

(Inherited from SoFieldContainer.)
Public methodIsBoundingBoxIgnoring

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

(Inherited from SoShape.)
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 SoNode.)
Public methodRayPick

Manages ray pick action.

(Inherited from SoBufferedShape.)
Public methodSearch
(Inherited from SoNode.)
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 methodSetShapeType

set the antialiasing type for this shape.

(Inherited from SoShape.)
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 methodShapeVertex

add a primitive vertex to the shape prevously started with OIV.Inventor.Nodes.SoShape.BeginShape(OIV.Inventor.Actions.SoAction, OIV.Inventor.Nodes.SoShape.TriangleShapes, OIV.Inventor.Details.SoFaceDetail).

(Inherited from SoShape.)
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
(Inherited from SoNode.)
Top
Properties
  NameDescription
Public propertyboundingBoxIgnoring

Whether to ignore this node during bounding box traversal.

(Inherited from SoShape.)
Public propertyclipGeometry

Specifies to clip the geometry at the volume boundaries.

Public propertycolorBuffer

Buffer object that contains the (optional) color values.

(Inherited from SoBufferedShape.)
Public propertycolorComponentsCount

Number of components in each color value.

(Inherited from SoBufferedShape.)
Public propertycolorComponentsType

OIV.Inventor.SbDataType.DataTypes type for the color values.

(Inherited from SoBufferedShape.)
Public propertycolorOffset

Offset in bytes to the first color value in the buffer.

(Inherited from SoBufferedShape.)
Public propertycolorStride

Stride in bytes between the first component of two consecutive colors.

(Inherited from SoBufferedShape.)
Public propertyindexBuffer

Buffer object that contains the (optional) indices.

(Inherited from SoBufferedShape.)
Public propertyindexOffset

Offset in bytes to the first index in the buffer.

(Inherited from SoBufferedShape.)
Public propertyindexType

OIV.Inventor.SbDataType.DataTypes type for the indices.

(Inherited from SoBufferedShape.)
Public propertyinterpolation

Interpolation mode.

Public propertyIsDisposable
ISafeDisposable interface implementation.
(Inherited from SoDisposable.)
Public propertynormalBuffer

Buffer object that contains the (optional) normal vectors.

(Inherited from SoBufferedShape.)
Public propertynormalComponentsType

OIV.Inventor.SbDataType.DataTypes type for the normal vectors.

(Inherited from SoBufferedShape.)
Public propertynormalOffset

Offset in bytes to the first normal vector in the buffer.

(Inherited from SoBufferedShape.)
Public propertynormalStride

Stride in bytes between the first component of two consecutive normals.

(Inherited from SoBufferedShape.)
Public propertynumVertices

Total number of vertices/indices or number of vertices/indices to be used per primitive.

(Inherited from SoBufferedShape.)
Public propertyoffset

Sets an offset value used for computing the texture coordinates.

Public propertyprimitiveRestartEnabled

Enable/disable the primitive restart feature.

(Inherited from SoBufferedShape.)
Public propertyprimitiveRestartValue

Index value for the primitive restart feature.

(Inherited from SoBufferedShape.)
Public propertyshapeType

Shape type to render.

(Inherited from SoBufferedShape.)
Public propertyshapeUsage

Defines the usage of the shape.

(Inherited from SoBufferedShape.)
Public propertytexCoordsBuffer

Buffer objects that contains the (optional) texture coordinates.

(Inherited from SoBufferedShape.)
Public propertytexCoordsComponentsCount

Number of components in each texture coordinate.

(Inherited from SoBufferedShape.)
Public propertytexCoordsComponentsType

OIV.Inventor.SbDataType.DataTypes type for the texture coordinates.

(Inherited from SoBufferedShape.)
Public propertytexCoordsOffset

Offset in bytes to the first texture coordinate in the buffer.

(Inherited from SoBufferedShape.)
Public propertytexCoordsStride

Stride in bytes between the first component of two consecutive texture coordinates.

(Inherited from SoBufferedShape.)
Public propertyuseNormalsGenerator

Indicates if the node should use the internal normal vector generator if no normals are defined.

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

Buffer object that contains the vertex data.

(Inherited from SoBufferedShape.)
Public propertyvertexComponentsCount

Number of components in each vertex.

(Inherited from SoBufferedShape.)
Public propertyvertexComponentsType (Inherited from SoBufferedShape.)
Public propertyvertexOffset

Offset in bytes to the first vertex within the buffer.

(Inherited from SoBufferedShape.)
Public propertyvertexStride

Stride in bytes between the first component of two consecutive vertices.

(Inherited from SoBufferedShape.)
Top
Remarks

This node defines a shape which is the intersection of the volume data defined by an OIV.VolumeViz.Nodes.SoVolumeData node and the 3D shape defined by an OIV.Inventor.Nodes.SoBufferedShape node. The shape defined by this intersection is colored using the data values from the current OIV.VolumeViz.Nodes.SoVolumeData node and color map from the current OIV.LDM.Nodes.SoTransferFunction node.

The shape defined by this intersection is textured using the data from the current OIV.VolumeViz.Nodes.SoVolumeData node and OIV.LDM.Nodes.SoTransferFunction node. The OIV.VolumeViz.Nodes.SoVolumeBufferedShape.interpolation field controls how the texture is interpolated. Texture coordinates are automatically computed for each vertex based on its position relative to the 3D extent of the volume. If texture coordinates are specified, they are ignored.

This node can be used to create custom "slices" through the volume, for example a cylinder slice. It can be considered a generalization of the OIV.VolumeViz.Nodes.SoOrthoSlice, OIV.VolumeViz.Nodes.SoObliqueSlice, OIV.VolumeViz.Nodes.SoFenceSlice, etc features. But note:

  • Compared to an equivalent standard slice (e.g. OIV.VolumeViz.Nodes.SoOrthoSlice), the rendering may be slightly different due to positioning and interpolation.

  • The standard slices (e.g. OIV.VolumeViz.Nodes.SoOrthoSlice) have "two-sided lighting" enabled by default as a convenience. This is not true for volume geometry nodes (which have the same default as their corresponding standard geometry node), so the "back" side of the geometry will not be lighted unless you enable two-sided lighting using an OIV.Inventor.Nodes.SoShapeHints node.

When set to false, the OIV.VolumeViz.Nodes.SoVolumeBufferedShape.clipGeometry field allows rendering of the portion of the geometry that does not intersect the volume data. This portion is not textured and is rendered as a regular OIV.Inventor.Nodes.SoBufferedShape.

This node uses 3D texturing and is not available if the hardware does not support this feature.

OIV.Inventor.Nodes.SoBufferedShape provides fields for:

  • Vertices

  • Indices (optional)

  • Colors (optional)

  • Normals (optional)

  • Texture coordinates (optional)

OIV.VolumeViz.Nodes.SoVolumeBufferedShape is useful to manage the rendering of large geometry, provide application control over where the data is stored (CPU or GPU) and to integrate rendering with the Open Inventor computing framework (through the OIV.Inventor.Devices.SoBufferObject classes).

OIV.VolumeViz.Nodes.SoVolumeBufferedShape can render many types of geometric primitives including points, lines, quads and triangles. (A single type must be specified per instance of OIV.VolumeViz.Nodes.SoVolumeBufferedShape.) You specify the type of primitive in the SoSFEnum field shapeType.

OIV.VolumeViz.Nodes.SoVolumeBufferedShape can render multiple primitives of the same type. You can specify the number of vertices (or indices if provided) to use for each primitive in the OIV.Inventor.Fields.SoMFInt32 field numVertices (similar to OIV.Inventor.Nodes.SoFaceSet).

You can also use the primitive restart feature to define multiple indexed strip shapes, for example TRIANGLE_STRIP or LINE_STRIP. The end of each primitive is marked by a special index value in the index buffer and this value can be specified in the primitiveRestartValue field. The behavior is similar to the "-1" value that can be used in Open Inventor indexed shape nodes like OIV.Inventor.Nodes.SoIndexedFaceSet, but is implemented on the GPU.

NOTE:

The geometry and its attributes must be stored in buffer objects (see OIV.Inventor.Devices.SoBufferObject). The buffer objects can be SoGLBufferObjects stored directly on the graphics board or SoCpuBufferObjects stored in system memory. This allows the application to control what data is stored where.

If lighting is enabled (there is no OIV.Inventor.Nodes.SoLightModel node or the model field of the OIV.Inventor.Nodes.SoLightModel is set to PHONG) and the normalBuffer field is not set, then normal vectors are automatically generated, similar to other geometry nodes. Normal generation is affected by the creaseAngle field of the OIV.Inventor.Nodes.SoShapeHints node if the vertices are NOT indexed. If the vertices are indexed the creaseAngle is forced to PI in order to have smooth surface rendering. It is not possible to display sharp edges by using indexed vertices if the normals are not set by the application. It is possible to disable normal generation (if for example the normals are generated by a geometry shader) by setting the useNormalsGenerator field to false. Note that normal generation is disabled in some cases. See the limitations section. If no normal vectors are specified or generated, and lighting is enabled, the primitive may not be rendered correctly.

OIV.VolumeViz.Nodes.SoVolumeBufferedShape provides fields to describe the content of each buffer, e.g. the data type and number of components in each buffer, as well as how to access the buffers, e.g. the offset into the buffer and "stride" separating data values in the buffer. The default values for offset and stride assume that the vertices, normals, etc are each in a separate buffer. However setting appropriate offset and stride allows, for example, vertices and normals to be interleaved in a single buffer. In this case the same buffer would be set into both the vertexBuffer and normalBuffer fields.

To disable computing the bounding box, which can take a long time with very large geometry, use the OIV.Inventor.Nodes.SoBBox node to specify a pre-computed bounding box.

Limitations

  • Projections: The projections used in the VolumeViz mechanism are not handled by OIV.VolumeViz.Nodes.SoVolumeBufferedShape.

  • Lighting: If there is no normalBuffer the normals are generated by Inventor. The crease angle (field of OIV.Inventor.Nodes.SoShapeHints) is not considered by the normal generator if the vertices are indexed (crease angle is PI). So if the application wants to render sharp edges on its shape, it must use the vertexBuffer without indices in the indexBuffer.

  • Transparency: If there is no color buffer, making the entire shape transparent using an OIV.Inventor.Nodes.SoMaterial node works as usual. However if there is a color buffer with RGBA values, note that Open Inventor does not currently check the color buffer for transparency (alpha values < 1). So in this case the OIV.VolumeViz.Nodes.SoVolumeBufferedShape will not be considered transparent geometry (even if there are alpha values < 1) and may not be rendered correctly. You can force Open Inventor to handle the shape as transparent geometry by putting an OIV.Inventor.Nodes.SoMaterial node with non-zero transparency before it in the scene graph.

  • Normal generation: Automatic generation of normal vectors is ONLY enabled when:

    • The vertexComponentsCount field is set to 3 (default),

    • The vertexComponentsType field is set to OIV.Inventor.SbDataType.DataTypes.FLOAT (default),

    • The primitiveRestartEnabled field is set to false (default), and

    • The primitives are faces (i.e. neither points nor lines).

  • OIV.Inventor.Actions.SoGetPrimitiveCountAction: When using the primitive restart feature, the triangle/line count returned by the OIV.Inventor.Actions.SoGetPrimitiveCountAction will not be accurate.

  • Concave polygons: Unlike (for example) OIV.Inventor.Nodes.SoFaceSet, OIV.VolumeViz.Nodes.SoVolumeBufferedShape does not automatically tesselate concave or complex polygons. Such primitives may not be rendered correctly.

  • OIV.Inventor.Actions.SoWriteAction: OIV.VolumeViz.Nodes.SoVolumeBufferedShape can be saved to and restored from a .iv file just like any other Open Inventor node. However, during the read operation any OpenGL buffer objects (OIV.Inventor.Devices.SoGLBufferObject) in the file will be created as CPU buffers (OIV.Inventor.Devices.SoCpuBufferObject) if there is no OpenGL context bound during the read operation.

  • Material binding (etc): OIV.VolumeViz.Nodes.SoVolumeBufferedShape effectively only supports per-vertex and per-vertex-indexed binding of materials, normals and texture coordinates.

  • Simplification: OIV.VolumeViz.Nodes.SoVolumeBufferedShape is ignored by the "simplify" actions (OIV.Inventor.Actions.SoShapeSimplifyAction, OIV.Inventor.Actions.SoGlobalSimplifyAction, OIV.Inventor.Actions.SoReorganizeAction).

Notes:

  • The volume size and orientation (like geometry) can be modified by transformation nodes in the scene graph and this in turn modifies the appearance of volume rendering nodes like OIV.VolumeViz.Nodes.SoVolumeBufferedShape. However the same transformation must be applied to the volume data node and all volume rendering nodes associated with that volume. So effectively any transformation nodes that affect the volume must be placed before the volume data node.

  • Composition with Multiple Data: 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. For instance,

    vec3 VVizTextureToTextureVec(in VVizDataSetId datasetSrc, in VVizDataSetId datasetDst, in vec3 texCoord);
    can be used to convert texture coordinates related to one dataset to texture coordinates related to another dataset. The conversion is based solely on the transformations applied to each dataset, which are defined by their model matrix and their extent. Please note that the model matrix of a dataset is defined by to the OIV.Inventor.Nodes.SoTransformation nodes that are placed before the OIV.LDM.Nodes.SoDataSet node in the order of the traversal.

FILE FORMAT/DEFAULT

VolumeBufferedShape {
clipGeometry true
offset 0
interpolation LINEAR
useNormalsGenerator true
shapeType TRIANGLES
numVertices 0
vertexBuffer NULL
vertexComponentsCount 3
vertexComponentsType OIV.Inventor.SbDataType.DataTypes.FLOAT
vertexStride 0
vertexOffset 0
normalBuffer NULL
normalComponentsType OIV.Inventor.SbDataType.DataTypes.FLOAT
normalStride 3 * sizeof(float)
normalOffset 0
indexBuffer NULL
indexType OIV.Inventor.SbDataType.DataTypes.UNSIGNED_INT32
indexOffset 0
colorBuffer NULL
colorComponentsType OIV.Inventor.SbDataType.DataTypes.FLOAT
colorStride 0
colorOffset 0
colorComponentsCount 3
texCoordsBuffer NULL
texCoordsComponentsType OIV.Inventor.SbDataType.DataTypes.FLOAT
texCoordsStride 0
texCoordsOffset 0
texCoordsComponentsCount 2
primitiveRestartEnabled false
primitiveRestartValue -1
}

ACTION BEHAVIOR

OIV.Inventor.Actions.SoGLRenderAction Draws primitives based on the current coordinates, normals, materials, drawing style, and so on.

OIV.Inventor.Actions.SoRayPickAction Picks primitives based on the current coordinates and transformation. Details about the intersection are returned in an OIV.Inventor.Details.SoFaceDetail.

OIV.Inventor.Actions.SoGetBoundingBoxAction Computes the bounding box that encloses all vertices of the face set with the current transformation applied to them. Sets the center to the real center of the bounding box: center{ (xmax + xmin) / 2, (ymax + ymin) / 2, (zmax + zmin) / 2 }

OIV.Inventor.Actions.SoCallbackAction If any triangle callbacks are registered with the action, they will be invoked for each successive triangle generated from each face in the set.

See Also