MPxPolyTrg Class Reference
Related help topics: #include <MPxPolyTrg.h>
Class Description
User defined poly triangulation support.
MPxPolyTrg is the the parent class for nodes which define a custom face triangulation for meshes. In order to override default maya triangulation, the user has to do the following things:
-
Derive a new node from MPxPolyTrg class.
-
Define a static function on the new node to triangulate a single face in the mesh. The signature of this function is given by polyTrgFnct type. The input to the triangulation function is:
- *vert - pointer to an array of vertex positions for the face. It size is 3*nbVertices.
- *norm - pointer to an array of per vertex normals for the face. It size is 3*nbVertices.
- *loopSizes - pointer to an array of loop sizes. The size of this array is nbLoops
- nbLoops - number of loops in the face.
- nbTrg - expected number of triangles to be generated.
Note: The number of vertices can be calculated by adding all the loop sizes.
The output of this function is an array of triangle description:
-
*trg - pointer to an integer array. This array is already allocated with the size of 3*nbTrg. It has to be filled with the triangle descriptions given by the face-relative position of vertices i.e.
nbTrg = 2 trg: 0 1 2 2 3 0
Tip: Refer to the example plugin: polyTrgNode for more details on how to implement it.
-
Register that function when the node is created for the first time (in the postConstructor() method) by calling the registerTrgFunction().
- Unregister the function in the destructor by calling the unregisterTrgFunction.
Once the node is defined, the user has to inform the mesh about it. For each mesh the user wants to override the default triangulation, he has to set the usertTrg attribute on the mesh to the name under which the function has been registered.
Example: /code setAttr mesh.userTrg -type "string" "triangulate"; /endcode
Once that attribute is set, the default maya triangulation is turned off and the one provided by the user is used to draw the mesh.
- Examples:
Inheritance diagram for MPxPolyTrg:
Public Types | |
| typedef void(* | polyTrgFnct) (const float *vert, const float *norm, const int *loopSizes, const int nbLoop, const int nbTrg, unsigned short *trg) |
| Pointer to a function which triangulates a poly face. | |
| Public Types inherited from MPxNode | |
| enum | Type { kDependNode, kLocatorNode, kDeformerNode, kManipContainer, kSurfaceShape, kFieldNode, kEmitterNode, kSpringNode, kIkSolverNode, kHardwareShader, kHwShaderNode, kTransformNode, kObjectSet, kFluidEmitterNode, kImagePlaneNode, kParticleAttributeMapperNode, kCameraSetNode, kConstraintNode, kManipulatorNode, kMotionPathNode, kClientDeviceNode, kThreadedDeviceNode, kAssembly, kSkinCluster, kGeometryFilter, kBlendShape, kLast } |
| Defines the type of node. More... | |
| enum | SchedulingType { kParallel, kSerial, kGloballySerial, kUntrusted , kDefaultScheduling = kSerial, kSerialize = kSerial, kGloballySerialize = kGloballySerial } |
| Defines the degree of parallelism of a node. More... | |
Public Member Functions | |
| MPxPolyTrg () | |
| Constructor. More... | |
| virtual | ~MPxPolyTrg () |
| Destructor. | |
| virtual void | postConstructor () |
| Post constructor. More... | |
| virtual MStatus | compute (const MPlug &plug, MDataBlock &dataBlock) |
| This method should be overridden in user defined nodes. More... | |
| virtual bool | isAbstractClass () const |
| Each new node has to implement that fuction. More... | |
| MStatus | registerTrgFunction (char *name, polyTrgFnct f) |
| Register a triangulation function with maya. More... | |
| MStatus | unregisterTrgFunction (char *name) |
| Public Member Functions inherited from MPxNode | |
| MPxNode () | |
| Constructor. More... | |
| virtual | ~MPxNode () |
| Destructor. | |
| virtual bool | getInternalValue (const MPlug &, MDataHandle &) |
| This method is overridden by nodes that store attribute data in some internal format. More... | |
| virtual bool | setInternalValue (const MPlug &, const MDataHandle &) |
| This method is overridden by nodes that store attribute data in some internal format. More... | |
| virtual int | internalArrayCount (const MPlug &) const |
| This method is overridden by nodes that have internal array attributes which are not stored in Maya's datablock. More... | |
| virtual void | copyInternalData (MPxNode *) |
| This method is overridden by nodes that store attribute data in some internal format. More... | |
| virtual MStatus | legalConnection (const MPlug &, const MPlug &, bool asSrc, bool &isLegal) const |
| This method allows you to check for legal connections being made to attributes of this node. More... | |
| virtual MStatus | legalDisconnection (const MPlug &, const MPlug &, bool asSrc, bool &isLegal) const |
| This method allows you to check for legal disconnections being made to attributes of this node. More... | |
| virtual MStatus | setDependentsDirty (const MPlug &plug, MPlugArray &plugArray) |
| This method can be overridden in user defined nodes to specify which plugs should be set dirty based upon an input plug {plugBeingDirtied} which Maya is marking dirty. More... | |
| virtual MStatus | preEvaluation (const MDGContext &context, const MEvaluationNode &evaluationNode) |
| Prepare a node's internal state for threaded evaluation. More... | |
| virtual MStatus | postEvaluation (const MDGContext &context, const MEvaluationNode &evaluationNode, PostEvaluationType evalType) |
| Clean up node's internal state after threaded evaluation. More... | |
| virtual SchedulingType | schedulingType () const |
| When overridden this method controls the degree of parallelism supported by the node during threaded evaluation. More... | |
| virtual MStatus | connectionMade (const MPlug &, const MPlug &, bool asSrc) |
| This method gets called when connections are made to attributes of this node. More... | |
| virtual MStatus | connectionBroken (const MPlug &, const MPlug &, bool asSrc) |
| This method gets called when connections are broken with attributes of this node. More... | |
| virtual MStatus | dependsOn (const MPlug &, const MPlug &, bool &depends) const |
| This method may be overridden by the user defined node. More... | |
| virtual bool | isPassiveOutput (const MPlug &) const |
| This method may be overridden by the user defined node if it wants to provide output attributes which do not prevent value modifications to the destination attribute. More... | |
| virtual MStatus | shouldSave (const MPlug &, bool &isSaving) |
| This method may be overridden by the user defined node. More... | |
| virtual MPlug | passThroughToOne (const MPlug &) const |
| This method may be overridden by nodes that have a one-to-one relationship between an input attribute and a corresponding output attribute. More... | |
| virtual bool | passThroughToMany (const MPlug &, MPlugArray &) const |
| This method is overridden by nodes that want to control the traversal behavior of some Maya search algorithms which traverse the history/future of shape nodes looking for directly related nodes. More... | |
| virtual Type | type () const |
| Returns the type of node that this is. More... | |
| virtual MStringArray | getFilesToArchive (bool shortName=false, bool unresolvedName=false, bool markCouldBeImageSequence=false) const |
| Use this method to return all external files used by this node. More... | |
| virtual void | getExternalContent (MExternalContentInfoTable &table) const |
| Returns the external content (files) that this node depends on. More... | |
| bool | addExternalContentForFileAttr (MExternalContentInfoTable &, const MObject &attr) const |
| Adds content info to the specified table from a file path attribute. More... | |
| bool | setExternalContentForFileAttr (const MObject &attr, const MExternalContentLocationTable &) |
| Sets content info in the specified attribute from the table. More... | |
| virtual void | setExternalContent (const MExternalContentLocationTable &) |
| Changes the location of external content in batch. More... | |
| virtual MTypeId | typeId () const |
| Returns the TYPEID of this node. More... | |
| virtual MString | typeName () const |
| Returns the type name of this node. More... | |
| virtual MString | name () const |
| Returns the name of this particular instance of this class. More... | |
| virtual MObject | thisMObject () const |
| Returns the MObject associated with this user defined node. More... | |
| virtual MStatus | setExistWithoutInConnections (bool flag) |
| This method specifies whether or not the node can exist without input connections. More... | |
| virtual bool | existWithoutInConnections (MStatus *ReturnStatus=NULL) const |
| Determines whether or not this node can exist without input connections. More... | |
| virtual MStatus | setExistWithoutOutConnections (bool flag) |
| This method specifies whether or not the node can exist without output connections. More... | |
| virtual bool | existWithoutOutConnections (MStatus *ReturnStatus=NULL) const |
| Determines whether or not this node can exist without output connections. More... | |
| MDataBlock | _forceCache (const MDGContext &) |
| This method is obsolete. More... | |
| virtual bool | getInternalValueInContext (const MPlug &, MDataHandle &, MDGContext &) |
| This method is obsolete. More... | |
| virtual bool | setInternalValueInContext (const MPlug &, const MDataHandle &, MDGContext &) |
| This method is obsolete. More... | |
| virtual int | internalArrayCount (const MPlug &, const MDGContext &) const |
| This method is obsolete. More... | |
Additional Inherited Members | |
| Static Public Member Functions inherited from MPxNode | |
| static MStatus | addAttribute (const MObject &attr) |
| This method adds a new attribute to a user defined node type during the type's initialization. More... | |
| static MStatus | inheritAttributesFrom (const MString &parentClassName) |
| This method allows a class of plugin node to inherit all of the attributes of a second class of plugin node. More... | |
| static MStatus | attributeAffects (const MObject &whenChanges, const MObject &isAffected) |
| This method specifies that a particular input attribute affects a specific output attribute. More... | |
| static const char * | className () |
| Returns the name of this class. More... | |
| Static Public Attributes inherited from MPxNode | |
| static MObject | message |
| message attribute | |
| static MObject | isHistoricallyInteresting |
| is historically interesting attribute | |
| static MObject | caching |
| caching attribute | |
| static MObject | state |
| state attribute | |
| static MObject | frozen |
| frozen attribute | |
| Protected Member Functions inherited from MPxNode | |
| virtual MDataBlock | forceCache () |
| USE _forceCache() IN SCRIPT. More... | |
| virtual void | setMPSafe (bool flag) |
| USE _setMPSafe() IN SCRIPT. More... | |
| virtual MStatus | setDoNotWrite (bool flag) |
| USE _setDoNotWrite() IN SCRIPT. More... | |
| virtual bool | doNotWrite (MStatus *ReturnStatus=NULL) const |
| USE _doNotWrite() IN SCRIPT. More... | |
| virtual MDataBlock | forceCache (const MDGContext &) |
| This method is obsolete. More... | |
Constructor & Destructor Documentation
| OPENMAYA_MAJOR_NAMESPACE_OPEN MPxPolyTrg | ( | ) |
Constructor.
The constructor should never call any methods from MPxPolyTrg or make any calls that require the existence of the MObject associated with the user defined node. The postConstructor method should be used to do any initialization of this kind.
Member Function Documentation
|
virtual |
Post constructor.
Internally maya creates two objects when a user defined node is created, the internal MObject and the user derived object. The association between the these two objects is not made until after the MPxPolyTrg constructor is called. This implies that no MPxPolyTrg member function can be called from the MPxPolyTrg constructor. The postConstructor will get called immediately after the constructor when it is safe to call any MPxPolyTrg member function.
Reimplemented from MPxNode.
- Examples:
|
virtual |
This method should be overridden in user defined nodes.
However, fror this particaular node we don't need to to do anything in the compute functione. Therefore, all we do is return MS:kSuccess in the derive class.
- Parameters
-
[in] plug plug representing the attribute that needs to be recomputed [in] block data block containing storage for the node's attributes
- Returns
- Status code
- Status Codes:
- MS::kSuccess Compute was successful
- MS::kFailure Compute failed
Reimplemented from MPxNode.
- Examples:
|
virtual |
Each new node has to implement that fuction.
It returns false since this is not an abstract class.
- Returns
- False
Reimplemented from MPxNode.
- Examples:
| MStatus registerTrgFunction | ( | char * | functName, |
| polyTrgFnct | funct | ||
| ) |
Register a triangulation function with maya.
The name provided as a first argument is the name under which the function is registered. This name has to be used when setting 'userTrg' attribute on a mesh.
- Parameters
-
[in] functName Function name under which the function is register with maya. [in] funct Pointer to the static function which implement a face triangulation.
- Returns
- Status code
- Status Codes:
- MS::kSuccess Compute was successful
- MS::kFailure Compute failed
| MStatus unregisterTrgFunction | ( | char * | functName | ) |
- Parameters
-
[in] functName Function name under which the function is register with maya.
- Returns
- Status code
- Status Codes:
- MS::kSuccess Compute was successful
- MS::kFailure Compute failed
The documentation for this class was generated from the following files:
- MPxPolyTrg.h
- MPxPolyTrg.cpp