MetadataSample/tweakMetadataNode.h

//
//  File: tweakMetadataNode.h
//
//  Description:
//      Example implementation of a node which takes in a mesh geometry
//      and modifies the metadata inside it in a manner
//      described by the "operation" attribute.
//        
//      To test the node, use the following Python commands
/*
        import maya.cmds as cmds
        cmds.loadPlugin( 'metadataPlugin' )
        tweakStruct = cmds.dataStructure( format='raw',
                                    asString='name=TweakStructure:int32=value' )
        tweak = cmds.createNode( 'tweakMetadata' )
        (xform, creator) = cmds.polyPlane( name='testPlane' )
        shape = cmds.listRelatives( xform, children=True )[0]
        cmds.connectAttr( '%s.outMesh' % creator, '%s.inMesh' % tweak )
        cmds.disconnectAttr( '%s.outMesh' % creator, '%s.inMesh' % shape )
        cmds.connectAttr( '%s.outMesh' % tweak, '%s.inMesh' % shape )
        cmds.setAttr( '%s.operation' % tweak, 1 )
        cmds.exportMetadata( shape )
        //
        // Output should show a set of metadata channels with random numbers
        //
        // Play around with the subdivision on "polyPlane" to generate
        // different metadata as component counts change.
        //
        // Notice that every evaluation causes a different set of random
        // numbers to be generated. To keep consistency with your metadata
        // you have to follow the DG principle of "the same inputs will
        // produce the same outputs". Try adding a random seed to this
        // example node to make the random numbers reproducible.
        //
*/

#include <maya/MPxNode.h> 

class tweakMetadataNode : public MPxNode
{
public:
                tweakMetadataNode   ();
            ~tweakMetadataNode  () override;

    static  void*       creator     ();
    static  MStatus     initialize  ();
    static  const char* nodeName        ();

    // Tweak function
    //
    MStatus     compute     ( const MPlug&, MDataBlock&) override;

    // Types of operations this node can perform
    //
    enum eOpTypes { kOpNone, kOpRandomize, kOpFill, kOpDouble };

public:
    // Node attributes
    static  MObject aOperation;
    static  MObject aInMesh;
    static  MObject aOutMesh;

    // This has to be globally unique or it could cause problems with file I/O
    static  MTypeId id;

private:
};

//-
// ==================================================================
// Copyright 2012 Autodesk, Inc.  All rights reserved.
// 
// This computer source code  and related  instructions and comments are
// the unpublished confidential and proprietary information of Autodesk,
// Inc. and are  protected  under applicable  copyright and trade secret
// law. They may not  be disclosed to, copied or used by any third party
// without the prior written consent of Autodesk, Inc.
// ==================================================================
//+