transCircleNode/transCircleNode.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 dependency graph node "transCircle".
//
// This plug-in demonstrates how to use an attribute that contains
// multiple values (a compound attribute). The translate attribute of the
// transform node is used which is composed of the elements: translateX,
// translateY, and translateZ, all of which are communicated over a single
// dependency graph connection. 
//
// To use this node, execute the MEL command "transCircleNode.mel" that contains
// the following: 
//
//  createNode transCircle -n circleNode1;
//  sphere -n sphere1 -r 1;
//  sphere -n sphere2 -r 2;
//  connectAttr sphere2.translate circleNode1.inputTranslate;
//  connectAttr circleNode1.outputTranslate sphere1.translate;
//  connectAttr time1.outTime circleNode1.input;
//
// This creates two spheres and a transCircle node. The translate attribute of sphere1
// is connected to the input of the transCircle node, and its output is connected to
// the translate attribute of sphere2.
//
// If the play button is pressed, the second sphere will circle around the first.
// If the first sphere is moved, the second will also move such that the first sphere
// always remains at the center of the circle.
//
// This plug-in also comes with a sample of an attribute editor template.
// This example suppresses the display of all attributes except scale and frames, and also
// provides an extra quick set control for the scale attribute that uses radio buttons
// to update the attribute value. 
//

#include <maya/MPxNode.h>

#include <maya/MString.h> 
#include <maya/MTypeId.h> 
#include <maya/MPlug.h>

#include <maya/MFnNumericAttribute.h>

#include <maya/MFnPlugin.h>
#include <maya/MDataBlock.h>
#include <maya/MDataHandle.h>

#include <string.h>
#include <maya/MIOStream.h>
#include <math.h>

class transCircle : public MPxNode
{
public:
                        transCircle() {};
    virtual             ~transCircle() {}; 

    virtual MStatus     compute( const MPlug& plug, MDataBlock& data );
    static  void*       creator();
    static  MStatus     initialize();

    static  MObject     input;            // The input value.
    static  MObject     inputTranslateX;  // The translate X value.  (input)
    static  MObject     inputTranslateY;  // The translate Y value.  (input)
    static  MObject     inputTranslateZ;  // The translate Z value.  (input)
    static  MObject     inputTranslate;
    static  MObject     outputTranslateX; // The translate X value.  (output)
    static  MObject     outputTranslateY; // The translate Y value.  (output)
    static  MObject     outputTranslateZ; // The translate Z value.  (output)
    static  MObject     outputTranslate;
    static  MObject     frames;           // Number of frames for one circle.
    static  MObject     scale;            // Size of circle.
    static  MTypeId     id;
};

MTypeId transCircle::id( 0x80013 );
MObject transCircle::input;        
MObject transCircle::frames;
MObject transCircle::scale;
MObject transCircle::inputTranslate;
MObject transCircle::outputTranslate;
MObject transCircle::inputTranslateX;
MObject transCircle::inputTranslateY;
MObject transCircle::inputTranslateZ;
MObject transCircle::outputTranslateX;
MObject transCircle::outputTranslateY;
MObject transCircle::outputTranslateZ;

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

MStatus transCircle::initialize()
{
    MFnNumericAttribute nAttr;
    MStatus             stat;

    input = nAttr.create( "input", "in", MFnNumericData::kDouble, 0.0 );
    nAttr.setStorable(true);

    inputTranslateX = nAttr.create( "inputTranslateX", "itX", 
                                    MFnNumericData::kDouble, 0.0 );
    nAttr.setStorable(true);

    inputTranslateY = nAttr.create( "inputTranslateY", "itY", 
                                    MFnNumericData::kDouble, 0.0 );
    nAttr.setStorable(true);

    inputTranslateZ = nAttr.create( "inputTranslateZ", "itZ", 
                                    MFnNumericData::kDouble, 0.0 );
    nAttr.setStorable(true);

    inputTranslate = nAttr.create( "inputTranslate", "it", 
                                    inputTranslateX,
                                    inputTranslateY,
                                    inputTranslateZ );
    nAttr.setStorable(true);
    nAttr.setDefault(0.0,0.0,0.0);

    outputTranslateX = nAttr.create( "outputTranslateX", "otX",
                                    MFnNumericData::kDouble, 0.0 );
    nAttr.setWritable(false);
    nAttr.setStorable(true);

    outputTranslateY = nAttr.create( "outputTranslateY", "otY",
                                    MFnNumericData::kDouble, 0.0 );
    nAttr.setWritable(false);
    nAttr.setStorable(true);

    outputTranslateZ = nAttr.create( "outputTranslateZ", "otZ",
                                    MFnNumericData::kDouble, 0.0 );
    nAttr.setWritable(false);
    nAttr.setStorable(true);

    outputTranslate = nAttr.create( "outputTranslate", "ot", 
                                    outputTranslateX,
                                    outputTranslateY,
                                    outputTranslateZ );
    nAttr.setWritable(false);
    nAttr.setStorable(true);
    nAttr.setDefault(0.0,0.0,0.0);

    scale = nAttr.create( "scale", "sc",
                                    MFnNumericData::kDouble, 10.0 );
    nAttr.setStorable(true);

    frames = nAttr.create( "frames", "fr",
                                    MFnNumericData::kDouble, 48.0 );
    nAttr.setStorable(true);

    stat = addAttribute( inputTranslate );
        if (!stat) { stat.perror("addAttribute"); return stat;}
    stat = addAttribute( input );
        if (!stat) { stat.perror("addAttribute"); return stat;}
    stat = addAttribute( scale );
        if (!stat) { stat.perror("addAttribute"); return stat;}
    stat = addAttribute( frames );
        if (!stat) { stat.perror("addAttribute"); return stat;}
    stat = addAttribute( outputTranslate );
        if (!stat) { stat.perror("addAttribute"); return stat;}

    stat = attributeAffects( inputTranslateX, outputTranslateX );
        if (!stat) { stat.perror("attributeAffects"); return stat;}
    stat = attributeAffects( inputTranslateY, outputTranslateY );
        if (!stat) { stat.perror("attributeAffects"); return stat;}
    stat = attributeAffects( inputTranslateZ, outputTranslateZ );
        if (!stat) { stat.perror("attributeAffects"); return stat;}
    stat = attributeAffects( inputTranslate, outputTranslateX );
        if (!stat) { stat.perror("attributeAffects"); return stat;}
    stat = attributeAffects( inputTranslate, outputTranslateY );
        if (!stat) { stat.perror("attributeAffects"); return stat;}
    stat = attributeAffects( inputTranslate, outputTranslateZ );
        if (!stat) { stat.perror("attributeAffects"); return stat;}
    stat = attributeAffects( inputTranslate, outputTranslate );
        if (!stat) { stat.perror("attributeAffects"); return stat;}
    stat = attributeAffects( input, outputTranslateX );
        if (!stat) { stat.perror("attributeAffects"); return stat;}
    stat = attributeAffects( input, outputTranslateY );
        if (!stat) { stat.perror("attributeAffects"); return stat;}
    stat = attributeAffects( scale, outputTranslateX );
        if (!stat) { stat.perror("attributeAffects"); return stat;}
    stat = attributeAffects( scale, outputTranslateY );
        if (!stat) { stat.perror("attributeAffects"); return stat;}
    stat = attributeAffects( frames, outputTranslateX );
        if (!stat) { stat.perror("attributeAffects"); return stat;}
    stat = attributeAffects( frames, outputTranslateY );
        if (!stat) { stat.perror("attributeAffects"); return stat;}

    return MS::kSuccess;
}

MStatus transCircle::compute( const MPlug& plug, MDataBlock& data )
{
    MStatus stat;
 
    bool k = ( plug == outputTranslateX ) |
             ( plug == outputTranslateY ) |
             ( plug == outputTranslateZ ) |
             ( plug == outputTranslate );
    if (!k) return MS::kUnknownParameter;

    MDataHandle inputData = data.inputValue( input, &stat );
    if (!stat) { stat.perror("inputValue: input"); return stat;}

    MDataHandle scaleData = data.inputValue( scale, &stat );
    if (!stat) { stat.perror("inputValue: scale"); return stat;}

    MDataHandle framesData = data.inputValue( frames, &stat );
    if (!stat) { stat.perror("inputValue: frames"); return stat;}

    MDataHandle transData  = data.inputValue( inputTranslate, &stat ); 
    if (!stat) { stat.perror("inputValue: inputTranslate"); return stat;}

    double3& iTranslate = transData.asDouble3();
    double currentFrame = inputData.asDouble();
    double scaleFactor  = scaleData.asDouble();
    double framesPerCircle = framesData.asDouble();
    double angle = 6.2831853 * ( currentFrame/framesPerCircle );
    double3 oTranslate;
    
    oTranslate[0] = iTranslate[0] + (sin( angle ) * scaleFactor);
    oTranslate[1] = iTranslate[1] + 1.0;
    oTranslate[2] = iTranslate[2] + (cos( angle ) * scaleFactor);

    MDataHandle otHandle = data.outputValue( outputTranslate ); 
    otHandle.set( oTranslate[0], oTranslate[1], oTranslate[2] );
    data.setClean(plug);

    return MS::kSuccess;
}

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

    status = plugin.registerNode( "transCircle", transCircle::id,
                         transCircle::creator, transCircle::initialize );
    if (!status) {
        status.perror("registerNode");
        return status;
    }

    return status;
}

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

    status = plugin.deregisterNode( transCircle::id );
    if (!status) {
        status.perror("deregisterNode");
        return status;
    }

    return status;
}