SoBufferedShape Class |
Node to render geometry stored in OIV.Inventor.Devices.SoBufferObject objects.
Namespace: OIV.Inventor.Nodes
The SoBufferedShape type exposes the following members.
Name | Description | |
---|---|---|
SoBufferedShape | Default constructor. |
Name | Description | |
---|---|---|
AffectsState | Overrides default method on OIV.Inventor.Nodes.SoNode. | |
BeginShape(SoAction, SoShapeTriangleShapes) | Calls BeginShape(action, shapeType, (OIV.Inventor.Details.SoFaceDetail ^)nullptr). (Inherited from SoShape.) | |
BeginShape(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. | |
Callback | Implements primitive generation for all shapes. | |
ComputeBBox(SoAction, SbBox3f, SbVec3f) | Computes the AABB bounding box if it must be updated. | |
ComputeBBox(SoAction, SbXfBox3d, SbVec3d) | Computes the OOB bounding box if it must be updated. | |
Copy | Calls Copy(false). (Inherited from SoNode.) | |
Copy(Boolean) | Creates and returns an exact copy of the node. | |
CopyFieldValues(SoFieldContainer) | Calls CopyFieldValues(fc, false). (Inherited from SoFieldContainer.) | |
CopyFieldValues(SoFieldContainer, Boolean) | Copies the contents of fc's fields into this object's fields. | |
Dispose |
Releases all resources used by SoDisposable.
(Inherited from SoDisposable.) | |
Distribute | (Inherited from SoNode.) | |
DoAction | (Inherited from SoNode.) | |
EnableNotify | Notification at this Field Container is enabled (if flag == true) or disabled (if flag == false). | |
EndShape | end shape previously started with OIV.Inventor.Nodes.SoShape.BeginShape(OIV.Inventor.Actions.SoAction, OIV.Inventor.Nodes.SoShape.TriangleShapes, OIV.Inventor.Details.SoFaceDetail). | |
Equals | Determines whether the specified Object is equal to the current Object. (Inherited from Object.) | |
FieldsAreEqual | Returns true if this object's fields are exactly equal to fc's fields. | |
Get | Returns the values of the fields of this object in the Open Inventor ASCII file format in the given string. | |
GetAllFields | Returns a list of fields, including the eventIn's and eventOut's. | |
GetAlternateRep | This method is called by actions to allow the node to provide an "alternate representation" when appropriate (typically depending on the action type). | |
GetBoundingBox | Manages getBoundingBoxAction action. | |
GetEventIn | Returns a the eventIn with the given name. | |
GetEventOut | Returns the eventOut with the given name. | |
GetField | Returns a the field of this object whose name is fieldName. | |
GetFieldName | Returns the name of the given field in the fieldName argument. | |
GetFields | Appends references to all of this object's fields to resultList, and returns the number of fields appended. | |
GetHashCode |
Overrides GetHashCode().
(Inherited from SoNetBase.) | |
GetMatrix | (Inherited from SoNode.) | |
GetName | Returns the name of an instance. | |
GetPrimitiveCount | Manages getPrimitiveCount action. | |
GetRenderEngineMode | Returns the supported Render engine mode. | |
GetRenderUnitID | (Inherited from SoNode.) | |
GetShapeType | Gets the current shape Full Scene Antialiasing type. | |
GetStringName | (Inherited from SoBase.) | |
GetType | Gets the Type of the current instance. (Inherited from Object.) | |
GLRender | Manages GLRender action. | |
GLRenderBelowPath | (Inherited from SoNode.) | |
GLRenderInPath | (Inherited from SoNode.) | |
GLRenderOffPath | (Inherited from SoNode.) | |
GrabEventsCleanup | (Inherited from SoNode.) | |
GrabEventsSetup | (Inherited from SoNode.) | |
HandleEvent | (Inherited from SoNode.) | |
HasDefaultValues | Returns true if all of the object's fields have their default values. | |
IsBoundingBoxIgnoring | Used by BoundingBoxAction to know if bounding box computation should be ignored or not. | |
IsNotifyEnabled | Notification is the process of telling interested objects that this object has changed. | |
IsOverride | Returns the state of the override flag. | |
IsSynchronizable | Gets the ScaleViz synchronizable state of this object. | |
Pick | (Inherited from SoNode.) | |
RayPick | Manages ray pick action. | |
Search | (Inherited from SoNode.) | |
Set | 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. | |
SetName | (Inherited from SoBase.) | |
SetOverride | Turns the override flag on or off. | |
SetShapeType | set the antialiasing type for this shape. | |
SetSynchronizable | Sets this to be a ScaleViz synchronizable object. | |
SetToDefaults | Sets all fields in this object to their default values. | |
ShapeVertex | 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). | |
ToString |
Converts this SoBase structure to a human readable string.
(Inherited from SoBase.) | |
Touch | Marks an instance as modified, simulating a change to it. | |
Write | (Inherited from SoNode.) |
Name | Description | |
---|---|---|
boundingBoxIgnoring | Whether to ignore this node during bounding box traversal. | |
colorBuffer | Buffer object that contains the (optional) color values. | |
colorComponentsCount | Number of components in each color value. | |
colorComponentsType | OIV.Inventor.SbDataType.DataTypes type for the color values. | |
colorOffset | Offset in bytes to the first color value in the buffer. | |
colorStride | Stride in bytes between the first component of two consecutive colors. | |
indexBuffer | Buffer object that contains the (optional) indices. | |
indexOffset | Offset in bytes to the first index in the buffer. | |
indexType | OIV.Inventor.SbDataType.DataTypes type for the indices. | |
IsDisposable | ISafeDisposable interface implementation.
(Inherited from SoDisposable.) | |
normalBuffer | Buffer object that contains the (optional) normal vectors. | |
normalComponentsType | OIV.Inventor.SbDataType.DataTypes type for the normal vectors. | |
normalOffset | Offset in bytes to the first normal vector in the buffer. | |
normalStride | Stride in bytes between the first component of two consecutive normals. | |
numVertices | Total number of vertices/indices or number of vertices/indices to be used per primitive. | |
primitiveRestartEnabled | Enable/disable the primitive restart feature. | |
primitiveRestartValue | Index value for the primitive restart feature. | |
shapeType | Shape type to render. | |
shapeUsage | Defines the usage of the shape. | |
texCoordsBuffer | Buffer objects that contains the (optional) texture coordinates. | |
texCoordsComponentsCount | Number of components in each texture coordinate. | |
texCoordsComponentsType | OIV.Inventor.SbDataType.DataTypes type for the texture coordinates. | |
texCoordsOffset | Offset in bytes to the first texture coordinate in the buffer. | |
texCoordsStride | Stride in bytes between the first component of two consecutive texture coordinates. | |
useNormalsGenerator | Indicates if the node should use the internal normal vector generator if no normals are defined. | |
UserData |
Gets or sets the user data to be contained by the field container.
(Inherited from SoFieldContainer.) | |
vertexBuffer | Buffer object that contains the vertex data. | |
vertexComponentsCount | Number of components in each vertex. | |
vertexComponentsType | OIV.Inventor.SbDataType.DataTypes for vertices. | |
vertexOffset | Offset in bytes to the first vertex within the buffer. | |
vertexStride | Stride in bytes between the first component of two consecutive vertices. |
OIV.Inventor.Nodes.SoBufferedShape 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.Inventor.Nodes.SoBufferedShape provides fields for:
Vertices
Indices (optional)
Colors (optional)
Normals (optional)
Texture coordinates (optional)
In this sense it is similar to the OIV.Inventor.Nodes.SoVertexProperty node, but OIV.Inventor.Nodes.SoVertexProperty is just a property node. OIV.Inventor.Nodes.SoBufferedShape also does the rendering of the shape. Properties that are not specified are taken from the traversal state (e.g. colors) or computed (e.g. normals).
OIV.Inventor.Nodes.SoBufferedShape can render many types of geometric primitives including points, lines, quads and triangles. (A single type must be specified per instance of OIV.Inventor.Nodes.SoBufferedShape.) You specify the type of primitive in the SoSFEnum field OIV.Inventor.Nodes.SoBufferedShape.shapeType.
OIV.Inventor.Nodes.SoBufferedShape 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 OIV.Inventor.Nodes.SoBufferedShape.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 OIV.Inventor.Nodes.SoBufferedShape.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:
Primitive restart must be explicitly enabled using the OIV.Inventor.Nodes.SoBufferedShape.primitiveRestartEnabled field.
Check availability of primitive restart using OIV.Inventor.Nodes.SoShape.IsPrimitiveRestartAvailable(OIV.Inventor.Misc.SoState).
The geometry and its attributes must be stored in buffer objects (see OIV.Inventor.Devices.SoBufferObject). The buffer objects can be SoGpuBufferObjects stored directly on the graphics board or SoCpuBufferObjects stored in system memory. This allows the application to control what data is stored where.
In the general case, when the underlying buffer object is modified using the OIV.Inventor.Devices.SoBufferObject API (setSize, map, memcpy, memset), the containing OIV.Inventor.Fields.SoSFBufferObject field needs to be notified using OIV.Inventor.Nodes.SoNode.Touch() in order for Open Inventor to take this modification into account. If OIV.Inventor.Nodes.SoNode.Touch() is not called, there is no guarantee that the modifications will be visible on the next rendering.
If the application needs to frequently modify the values of an OIV.Inventor.Devices.SoBufferObject, calling OIV.Inventor.Nodes.SoNode.Touch() on the field can result in an undesirable decrease in performance. Instead, it is recommended to use an instance of OIV.Inventor.Devices.SoGpuBufferObject and set the OIV.Inventor.Nodes.SoBufferedShape.shapeUsage field to DYNAMIC. These settings guarantee that this buffer data will be used directly for rendering, and eliminate the need to call OIV.Inventor.Nodes.SoNode.Touch() on the field. It also guarantees that modifications to the buffer done by shaders will be properly taken into account.
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 OIV.Inventor.Nodes.SoBufferedShape.normalBuffer field is not set, then Open Inventor will automatically compute normal vectors, but only in some cases (see Limitations section). Normal generation is affected by the creaseAngle field of the OIV.Inventor.Nodes.SoShapeHints node, but only if the vertices are NOT indexed (indexBuffer field is not set). If the vertices are indexed the creaseAngle is forced to PI, creating a smooth surface rendering. If the application needs to render sharp edges on a shape, either compute normal vectors and set the normalBuffer field or do not use the indexBuffer field. It is possible to disable normal generation (if for example the normals are generated by a geometry shader) by setting the OIV.Inventor.Nodes.SoBufferedShape.useNormalsGenerator field to false. If no normal vectors are specified or generated, and lighting is enabled, the primitive may not be rendered correctly.
OIV.Inventor.Nodes.SoBufferedShape 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
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.Inventor.Nodes.SoBufferedShape 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: If lighting is enabled and the normalBuffer field is not set, then Open Inventor will automatically compute normal vectors, but only in some cases. Automatic generation of normal vectors is ONLY enabled when:
The OIV.Inventor.Nodes.SoBufferedShape.vertexComponentsCount field is set to 2 or 3,
The OIV.Inventor.Nodes.SoBufferedShape.primitiveRestartEnabled field is set to false (default), and
The primitives are TRIANGLES, TRIANGLE_STRIP or QUADS. Note: The crease angle (see OIV.Inventor.Nodes.SoShapeHints) is not used by the normal generator if the vertices are indexed. If the application needs to render sharp edges on a shape, either compute normal vectors and set the normalBuffer field or do not use the indexBuffer field.
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.Inventor.Nodes.SoBufferedShape does NOT automatically tesselate concave or complex polygons. Such primitives may not be rendered correctly.
OIV.Inventor.Actions.SoWriteAction: OIV.Inventor.Nodes.SoBufferedShape can be saved to and restored from a .iv file just like any other Open Inventor node. However, during the read operation any GPU buffer objects (OIV.Inventor.Devices.SoGpuBufferObject) in the file will be created as CPU buffers (OIV.Inventor.Devices.SoCpuBufferObject).
Material binding (etc): OIV.Inventor.Nodes.SoBufferedShape effectively only supports per-vertex and per-vertex-indexed binding of materials, normals and texture coordinates using the values found in its own buffers.
Example using CPU buffer:
float[] vertices = new float[9 * 3] { 1.0f, 0.5f,0.0f, 0.0f, 1.0f,0.0f, -1.0f,0.5f,0.0f, -1.0f,-1.0f,0.0f, 1.0f,-1.0f,0.0f, 1.0f,0.0f,0.0f, -1.0f,0.0f,0.0f, -1.0f,-1.5f,0.0f, 1.0f,-1.5f,0.0f }; Int32[] numVerts = new Int32[3] { 3, 4, 2 }; SbNativeArray<float> vertArray = new SbNativeArray<float>(vertices); SoCpuBufferObject vertBuffer = new SoCpuBufferObject((SbNativeArray<byte>)vertArray); SoBufferedShape shape = new SoBufferedShape(); shape.shapeType.SetValue( "LINE_STRIP" ); shape.numVertices.SetValues( 0, numVerts ); shape.vertexBuffer.Value = vertBuffer;
Example using GPU buffer:
float[] vertices = new float[9 * 3] { 1.0f, 0.5f,0.0f, 0.0f, 1.0f,0.0f, -1.0f,0.5f,0.0f, -1.0f,-1.0f,0.0f, 1.0f,-1.0f,0.0f, 1.0f,0.0f,0.0f, -1.0f,0.0f,0.0f, -1.0f,-1.5f,0.0f, 1.0f,-1.5f,0.0f }; Int32[] numVerts = new Int32[3] { 3, 4, 2 }; SbNativeArray<float> vertArray = new SbNativeArray<float>(vertices); SoCpuBufferObject vertBuf = new SoCpuBufferObject( (SbNativeArray<byte>)vertArray ); SoGLContext glContext = new SoGLContext(true); glContext.Bind(); SoGpuBufferObject gpuBuffer = new SoGpuBufferObject( SoGpuBufferObject.BufferAccessFrequencies.STATIC, SoGpuBufferObject.BufferAccessNatures.SHARED ); gpuBuffer.SetSize( cpuBuffer.GetSize() ); // Set the buffer size (allocate memory) gpuBuffer.Memcpy ( cpuBuffer ); // Copy data into the buffer glContext.Unbind(); SoBufferedShape shape = new SoBufferedShape(); shape.shapeType.SetValue("LINE_STRIP"); shape.numVertices.SetValues(0, numVerts); shape.vertexBuffer.Value = gpuBuffer; root.AddChild(shape);
LIMITATIONS: OIV.Inventor.Nodes.SoBufferedShape needs a graphic card supporting vertex buffer objects, if not available shape won't be rendered.
BufferedShape {
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 |
OIV.Inventor.Actions.SoGLRenderAction, OIV.Inventor.Actions.SoCallbackAction, SoBoundingBoxAction Do the actual rendering / bounding box computation.