C++ API Reference
MPxTopologyEvaluator Class Reference

Topology override evaluator for fine grain evaluation graphs. More...

#include <MPxTopologyEvaluator.h>

Public Member Functions

 MPxTopologyEvaluator ()
 Constructor. More...
 
virtual ~MPxTopologyEvaluator ()
 Destructor.
 
bool active (MStatus *ReturnStatus=nullptr) const
 Is evaluator active. More...
 
void setActive (bool isNowActive, MStatus *ReturnStatus=nullptr)
 Change evaluator active state. More...
 
virtual bool markIfSupported (const MEvaluationNode *node)
 Mark supported nodes. More...
 
virtual void preMakeTopology (const MEvaluationGraph *graph)
 Prepare for making topology for given graph. More...
 
virtual bool makeTopology (MTopologyClusterNode *cluster)
 Create subgraph nodes and connect to connection ports for given topology cluster. More...
 
virtual void postMakeTopology (const MEvaluationGraph *graph)
 Finalize making of topology for given graph. More...
 

Static Public Member Functions

static const char * className ()
 Returns the name of this class. More...
 

Detailed Description

Topology override evaluator for fine grain evaluation graphs.

Evaluation graph is representing evaluation requirements and dependencies between them. We coupled granularity of evaluation graph to granularity of dependency graph by making smallest execution equal to single dependency node. In many cases this causes no trouble and we can use custom evaluators to group bunch of nodes together and reduce the number of execution. But there are real cases where being able to express single dependency node as multiple executions (= multiple evaluation nodes) can give us better control about how things are evaluated and unlock even more performance. Some of this was possible as part of cluster evaluation, but evaluating a single node and scheduling evaluation of cluster evaluation was non-trivial and in many cases would just create instabilities.

New concept was created which allows topology override of evaluation graph. This makes possible to have total control over granularity, leverage already existing scheduling constraints and scheduling graph. Supports partial evaluation for minimal evaluation of cluster content. Finally, allows better resource utilization since execution of cluster content doesn't have to wait for entire upstream to start and downstream can start as soon as dependencies are ready (sort of transparent clusters, but much more configurable and with no constraints on granularity).

Note
This type of evaluator is claiming nodes in the same way as any other evaluator (i.e. marking if supported). Evaluation is completely done by subgraph nodes, meaning none of evaluation methods will be called on this evaluator and this is why they are final.
Examples:
testMTopologyEvaluator/testMTopologyEvaluator.h.

Constructor & Destructor Documentation

Constructor.

Also creates our internal evaluator.

Member Function Documentation

bool active ( MStatus ReturnStatus = nullptr) const

Is evaluator active.

Parameters
[out]ReturnStatusReturns success or object error when internal object is not associated with this evaluator
Returns
true if evaluator should receive scheduling then evaluation notifications.
void setActive ( bool  isNowActive,
MStatus ReturnStatus = nullptr 
)

Change evaluator active state.

Parameters
[in]isNowActiveNew active state
[out]ReturnStatusReturns success or object error when internal object is not associated with this evaluator
bool markIfSupported ( const MEvaluationNode node)
virtual

Mark supported nodes.

This call marks node as supported by the evaluator. It is safe to cause evaluation in this call, but this evaluation cost will increase partitioning time and won't reduce the next evaluation time. It is up to the developer to decide whether evaluation is required or the already-evaluated data in the datablock can be used. Call .outputValue/.outputArrayValue in the first case and .inputValue/.inputArrayValue in the second (the first is preferred).

Zero, one or more nodes can be marked by this call, since the dependency node design can involve multiple nodes being joined in a single setup (e.g. IK chains).

Parameters
[in]nodeNode to set or clear supported bit
Examples:
testMTopologyEvaluator/testMTopologyEvaluator.h.
void preMakeTopology ( const MEvaluationGraph graph)
virtual

Prepare for making topology for given graph.

Topology for this evaluation is about to be created. This call happens once, just before makeTopology for each cluster is called.

Parameters
[in]graphGraph which is constructing override topology
bool makeTopology ( MTopologyClusterNode cluster)
virtual

Create subgraph nodes and connect to connection ports for given topology cluster.

Parameters
[in]clusterTopology cluster which to construct override topology
Examples:
testMTopologyEvaluator/testMTopologyEvaluator.h.
void postMakeTopology ( const MEvaluationGraph graph)
virtual

Finalize making of topology for given graph.

This call happens once, just after makeTopology for each cluster was called.

Parameters
[in]graphGraph which is constructing override topology
const char * className ( )
static

Returns the name of this class.

Returns
Name of this class.

The documentation for this class was generated from the following files: