moveCurveCVsCmd/moveCurveCVsCmd.cpp

//-
// ==========================================================================
// Copyright 1995,2006,2008 Autodesk, Inc. All rights reserved.
//
// Use of this software is subject to the terms of the Autodesk
// license agreement provided at the time of installation or download,
// or which otherwise accompanies this software in either electronic
// or hard copy form.
// ==========================================================================
//+

// 
// DESCRIPTION:
//
// Produces the MEL command "moveCurveCVs".
//
// This is a simple little plug-in that takes the selected CVs of a NURBS curves
// and moves them to the origin. It is not a very practical plug-in, but
// it demonstrates retrieving CVs from a selection list and the use of the Curve CV iterator.
//
// To use the plug-in:
//  (1) Draw a curve.
//  (2) Switch Maya from Object selection mode to Component selection mode.
//  (3) Pick some or all the CVs of the curve.
//  (4) Type the command "moveCurveCVs" in the command window to move the CVs.  
//

#include <maya/MIOStream.h>
#include <maya/MPxCommand.h>
#include <maya/MString.h>
#include <maya/MArgList.h>
#include <maya/MGlobal.h>
#include <maya/MSelectionList.h>
#include <maya/MItSelectionList.h>
#include <maya/MPoint.h>
#include <maya/MDagPath.h>
#include <maya/MFnPlugin.h>
#include <maya/MFnNurbsCurve.h>
#include <maya/MItCurveCV.h>

class moveCurveCVs : public MPxCommand
{
public:
                    moveCurveCVs() {};
    virtual         ~moveCurveCVs(); 

    MStatus         doIt( const MArgList& args );
    static void*    creator();
};

moveCurveCVs::~moveCurveCVs() {}

void* moveCurveCVs::creator()
{
    return new moveCurveCVs();
}

MStatus moveCurveCVs::doIt( const MArgList& )
{
    MStatus stat;

    // Create a selection list iterator
    // set the filter moveCurveCVsComponents
    //
    MSelectionList list;
    MGlobal::getActiveSelectionList( list );
    MItSelectionList * iter = new MItSelectionList( list,
                                                    MFn::kCurveCVComponent,
                                                    &stat );

    if ( MS::kSuccess == stat ) {
        MDagPath    mdagPath;       // Item dag path
        MObject     mComponent;     // Current component
        double      coord[4] = {0.0,0.0,0.0,0.0};
        MPoint      point( coord );

        // Iterate over all selected curves
        //
        for ( ; !iter->isDone(); iter->next() ) 
        {
            // Create a function set to operate on selected curves
            //
            iter->getDagPath( mdagPath, mComponent );
            MItCurveCV fnmoveCurveCVs( mdagPath, mComponent, &stat );

            if ( MS::kSuccess == stat ) {
                for ( ; !fnmoveCurveCVs.isDone(); fnmoveCurveCVs.next() )
                {
                    fnmoveCurveCVs.setPosition( point, MSpace::kWorld );
                }
                fnmoveCurveCVs.updateCurve();
            }
            else {
                cerr << "Function set error\n";
            }
        }
    }
    else {
        cerr << "Error creating selection list iterator\n";
    }
    return stat;
}


MStatus initializePlugin( MObject obj )
{
    MStatus   status;
    MFnPlugin plugin( obj, PLUGIN_COMPANY, "3.0", "Any");

    status = plugin.registerCommand( "moveCurveCVs", moveCurveCVs::creator );
    if (!status) {
        status.perror("registerCommand");
        return status;
    }

    return status;
}

MStatus uninitializePlugin( MObject obj)
{
    MStatus   status;
    MFnPlugin plugin( obj );

    status = plugin.deregisterCommand( "moveCurveCVs" );
    if (!status) {
        status.perror("deregisterCommand");
        return status;
    }

    return status;
}