manipOverride/manipOverride.cpp

//-
// ==========================================================================
// Copyright 2020 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.
// ==========================================================================
//+

// 
// manipOverride.cpp
// 
// This plug-in demonstrates how to create user-defined manipulators
// from a user-defined context and apply the manipulator to a custom attribute
// defined on a custom transform node.  The custom transform node has a
// custom attribute defined, RockInX.  A distance base manip is defined as
// the custom manipulator and gets attached to the RockInX attribute when selected.
//
// The attachment of the manipulator is performed by an event callback that
// is registered for PostToolChanged and SelectionChanged events.  
//

#include <stdio.h>
#include <stdlib.h>
#include <maya/M3dView.h>
#include <maya/MArgList.h>
#include <maya/MCursor.h>
#include <maya/MDagPath.h>
#include <maya/MEventMessage.h>
#include <maya/MFn.h>
#include <maya/MFnCamera.h>
#include <maya/MFnDistanceManip.h> 
#include <maya/MFnPlugin.h>
#include <maya/MFnTransform.h>
#include <maya/MGlobal.h>
#include <maya/MIOStream.h>
#include <maya/MItSelectionList.h>
#include <maya/MModelMessage.h>
#include <maya/MPxContext.h>
#include <maya/MPxContextCommand.h>
#include <maya/MPxManipContainer.h> 
#include <maya/MPxNode.h>
#include <maya/MPxSelectionContext.h>
#include <maya/MPxToolCommand.h>
#include <maya/MPlug.h>
#include <maya/MPoint.h>
#include <maya/MQuaternion.h>
#include <maya/MSelectionList.h>
#include <maya/MVector.h>
#include "rockingTransform2.h"
#include "customTriadManip.h"

#define     customAttributeString   "rockx"

MCallbackId cid1 = 0;
MCallbackId cid2 = 0;
static bool     isSetting = false;

// This constant is used to translate mouse delta values into floating point delta
// values to modify the attached attributes.
static double       scaleFactor = 0.01;

// Callback function for messages.  This callback will be registered for the PostToolChanged
// and SelectionChanged events.
//
static void eventCB(void * data);

//
// The customAttr tool command
//
// - This command is used to turn the interactions with the manip
//   or the context into an undoable action.
//
#define     ATTR_CMD_NAME "customAttrToolCmd"
#define     DOIT        0
#define     UNDOIT      1
#define     REDOIT      2

class customAttrCmd : public MPxToolCommand
{
public:
    customAttrCmd();
    ~customAttrCmd() override; 

    MStatus     doIt( const MArgList& args ) override;
    MStatus     redoIt() override;
    MStatus     undoIt() override;
    bool        isUndoable() const override;
    MStatus     finalize() override;
    
public:
    static void* creator();

    void        setDelta(double d);
    void        setDragX() {dragX = true;}

private:
    double      delta;
    bool        dragX;
    MStatus     action( int flag ); // do the work here
    void        parseDrag(int axis);
};

customAttrCmd::customAttrCmd( )
{
    setCommandString( ATTR_CMD_NAME );
    dragX = false;
}

customAttrCmd::~customAttrCmd()
{}

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

bool customAttrCmd::isUndoable() const
//
// Description
//     Set this command to be undoable.
//
{
    return true;
}

void customAttrCmd::setDelta(double d)
//
// Description
//     This method sets the delta value that will be used when
//     the command is executed.
//
{
    delta = d * scaleFactor;
}

MStatus customAttrCmd::finalize()
//
// Description
//     This method constructs the final command syntax which will be called
//     to execute/undo/redo the action.  The syntax of the generated command
//     will be:
//
//     customAttrToolCmd <deltaVal>
//
//     where <deltaVal> is the most recently set value from the call to
//     customAttrCmd::setDelta().
//
{
    MArgList command;
    command.addArg( commandString() );
    command.addArg( delta );

    // This call adds the command to the undo queue and sets
    // the journal string for the command.
    //
    return MPxToolCommand::doFinalize( command );
}

MStatus customAttrCmd::doIt( const MArgList& args )
//
// Description
//    This method executes the command given the passed arguments.
//    The arguments consist of a delta value and one or more axes
//    along which the delta value will be applied.
//
{
    MStatus stat;

    delta = args.asDouble( 0, &stat );

    return action( DOIT );
}

MStatus customAttrCmd::undoIt( )
//
// Description
//      Undo last delta value.
//
{
    return action( UNDOIT );
}

MStatus customAttrCmd::redoIt( )
//
// Description
//      Redo last delta value.
//
{
    return action( REDOIT );
}

MStatus customAttrCmd::action( int flag )
//
// Description
//    Do the actual work here to move the objects by the
//    command's delta value.  The objects will come from those
//    on the active selection list.
//
{
    MStatus stat;
    double d = delta;

    switch( flag )
    {
        case UNDOIT:    // undo
            d = -d;
            break;
        case REDOIT:    // redo
            break;
        case DOIT:      // do command
            break;
        default:
            break;
    }

    // Create a selection list iterator
    //
    MSelectionList slist;
    MGlobal::getActiveSelectionList( slist );
    MItSelectionList iter( slist, MFn::kInvalid, &stat );

    if ( MS::kSuccess == stat ) {
        MDagPath    mdagPath;       // Item dag path
        MObject     mComponent;     // Current component

        // Processs all selected objects
        //
        for ( ; !iter.isDone(); iter.next() ) 
        {
            // Get path and possibly a component
            //
            iter.getDagPath( mdagPath, mComponent );

            MFnTransform transFn( mdagPath, &stat );
            if ( MS::kSuccess == stat ) {

                // If the selected object is of type rockingTransform2,
                // then set the appropriate plug value depending on which axes
                // the command is operating on.
                if (transFn.typeId() == rockingTransform2Node::id)
                {
                    MPlug plg = transFn.findPlug(customAttributeString, true);
                    double val;
                    plg.getValue(val);
                    plg.setValue(val+d);
                }
                continue;
            }

        } // for
    }
    else {
        cerr << "Error creating selection list iterator" << endl;
    }
    return MS::kSuccess;
}


//
// The customAttrManip2 manipulator
//
// - This class defines the manipulator which will be used
//   when the tool becomes the active context.  It consists of
//   three distance base manips aligned along the X, Y, and Z
//   axes of the attached transform's coordinate system.  The
//   internals of the manipulator base class handle the management
//   of command information so that undo/redo are handled.
//
class customAttrManip2 : public MPxManipContainer
{
public:
    customAttrManip2();
    ~customAttrManip2() override;
    
    static void *   creator();
    static MStatus  initialize();
    MStatus createChildren() override;
    MStatus connectToDependNode(const MObject &node) override;

    MVector         nodeTranslation() const;
    MQuaternion     nodeRotation() const;

    void            updateManipLocations();

    MDagPath        fManip;
    MDagPath        fNodePath;

public:
    static MTypeId  id;
};


MTypeId customAttrManip2::id( 0x80025 );

customAttrManip2::customAttrManip2() 
{ 
    // Do not call createChildren from here - 
    // MayaPtr has not been set up yet.
}


customAttrManip2::~customAttrManip2() 
{
}


void *customAttrManip2::creator()
{
     return new customAttrManip2();
}


MStatus customAttrManip2::initialize()
{ 
    MStatus stat;
    stat = MPxManipContainer::initialize();
    return stat;
}

MStatus customAttrManip2::createChildren()
//
// Description
//    Create the geometry of the manip.  This consists of a single
//    distance manip.
//
{
    fManip = addDistanceManip("customtManip", "customPoint");

    return MStatus::kSuccess;
}

MQuaternion customAttrManip2::nodeRotation() const
//
// Description
//    Query and return the rotation values for the attached transform node.
//
{
    MFnDagNode dagFn(fNodePath);
    MDagPath path;
    dagFn.getPath(path);
    MFnTransform transformFn(path);
    MQuaternion q;
    transformFn.getRotation( q, MSpace::kWorld );
    return q;
}

MVector customAttrManip2::nodeTranslation() const
//
// Description
//    Query and return the translation values for the attached transform node.
//
{
    MFnDagNode dagFn(fNodePath);
    MDagPath path;
    dagFn.getPath(path);
    MFnTransform transformFn(path);
    return transformFn.getTranslation(MSpace::kWorld);
}

void customAttrManip2::updateManipLocations()
//
// Description
//    This method places the manip in the scene according to the information
//    obtained from the attached transform node.  The position and orientation
//    of the distance manip is determined.
//
{
    MVector  trans = nodeTranslation();
    MQuaternion  q = nodeRotation();

    MFnDistanceManip freePointManipFn(fManip);

    MVector vecX(1.0, 0.0, 0.0);

    freePointManipFn.setDirection(vecX);
    freePointManipFn.rotateBy(q);
    freePointManipFn.setTranslation(trans, MSpace::kWorld);
}

MStatus customAttrManip2::connectToDependNode(const MObject &node)
//
// Description
//    This method activates the manip on the given transform node.
//
{
    MStatus stat = MStatus::kSuccess;

    // Get the DAG path
    //
    MFnDagNode dagNodeFn(node);
    dagNodeFn.getPath(fNodePath);

    // Connect the plugs to the manip.
    MFnDependencyNode nodeFn(node);    
    MFnDistanceManip distManipFn(fManip);
    MPlug cPlug = nodeFn.findPlug(customAttributeString,  true,  &stat);
    if( stat == MStatus::kSuccess )
        distManipFn.connectToDistancePlug(cPlug);

    finishAddingManips();
    updateManipLocations();

    MPxManipContainer::connectToDependNode(node);        
    return stat;
}


//
// The customAttrManip2 Context
//
// - Tool contexts are custom event handlers and are used to 
//   process mouse interactions.  The context subclass 
//   allows you to override press/drag/release events.
//
//  This context contains the customAttrManip2 defined above and
//  also performs its own mouse processing by handling the middle
//  mouse.  When the middle mouse button is lifted at the end of
//  a drag, a command is constructed for use in undo/redo.
//
#define MOVEHELPSTR     "Drag the distance manips to change values on custom attributes"
#define MOVETITLESTR    "customAttrManip2"


class customAttrCtx : public MPxSelectionContext
{
public:
    customAttrCtx();

    void    toolOnSetup(MEvent &event) override;
    void    toolOffCleanup() override;
    MStatus doEnterRegion(MEvent &event) override;
    MStatus doPress(MEvent &event) override;
    MStatus doDrag(MEvent &event) override;
    MStatus doRelease(MEvent &event) override;

    customAttrManip2 * caManip;

private:
    M3dView         view;
    MEvent::MouseButtonType downButton;
    short           startPos_x, endPos_x;
    short           startPos_y, endPos_y;
    double          delta;
    customAttrCmd * cmd;
};


void updateManipulators(void * data);
MCallbackId id1;


customAttrCtx::customAttrCtx()
{
    MString str(MOVETITLESTR);
    setTitleString(str);
}

void customAttrCtx::toolOnSetup(MEvent &)
{
    MString str(MOVEHELPSTR);
    setHelpString(str);

    updateManipulators(this);
    MStatus status;
    id1 = MModelMessage::addCallback(MModelMessage::kActiveListModified,
                                     updateManipulators, 
                                     this, &status);
    if (!status) {
        cerr << "Model addCallback failed\n";
    }
}


void customAttrCtx::toolOffCleanup()
//
// Description
//     This method is called when the context is no longer the current context.
//     The manipulator is removed from the scene.
//
{
    MStatus status;
    status = MModelMessage::removeCallback(id1);
    if (!status) {
        cerr << "Model remove callback failed\n";
    }
    MPxContext::toolOffCleanup();
}

MStatus customAttrCtx::doPress( MEvent & event )
//
// Description
//     This method is called when a mouse button is pressed while this context is
//    the current context.
//
{
    // Let the parent class handle the event first in case there is no object
    // selected yet.  The parent class will perform any necessary selection.
    MStatus stat = MPxSelectionContext::doPress( event );

    // If an object has been selected, then process the event.  Otherwise,
    // ignore it as there is nothing to do.
    if ( !isSelecting() ) {
        if (event.mouseButton() == MEvent::kMiddleMouse)
        {
            setCursor(MCursor::handCursor);
            view = M3dView::active3dView();

            // Create an instance of the customAttrCmd tool command and initialize
            // its delta value to 0.  As the mouse drags, the delta value will change.
            // when the mouse is lifted, a final command will be constructed with the
            // most recently set delta value and axis specifications.
            cmd = (customAttrCmd *)newToolCommand();
            cmd->setDelta(0.0);

            event.getPosition( startPos_x, startPos_y );

            // Determine the channel box attribute which will be operated on by the
            // dragging motion and set the state of the command accordingly.
            unsigned int i;
            MStringArray result;
            MGlobal::executeCommand(
                    "channelBox -q -selectedMainAttributes $gChannelBoxName", result);
            for (i=0; i<result.length(); i++)
            {
                if (result[i] == customAttributeString)
                {
                    cmd->setDragX();
                    break;
                }
            }
        }
    }

    return stat;
}

MStatus customAttrCtx::doDrag( MEvent & event )
//
// Description
//     This method is called when a mouse button is dragged while this context is
//    the current context.
//
{
    MStatus stat;

    // If an object has been selected, then process the drag.  Otherwise, pass the
    // event on up to the parent class.
    if ((!isSelecting()) && (event.mouseButton() == MEvent::kMiddleMouse)) {

        event.getPosition( endPos_x, endPos_y );

        // Undo the command to erase the previously set delta value from the
        // node, set a new delta value in the command and redo the command to
        // set the values in the node.
        cmd->undoIt();
        cmd->setDelta(endPos_x - startPos_x);
        stat = cmd->redoIt();
        view.refresh( true );
    }
    else
        stat = MPxSelectionContext::doDrag( event );

    return stat;
}

MStatus customAttrCtx::doRelease( MEvent & event )
//
// Description
//     This method is called when a mouse button is released while this context is
//    the current context.
//
{
    // Let the parent class handle the event.
    MStatus stat = MPxSelectionContext::doRelease( event );

    // If an object is selected, process the event if the middle mouse button
    // was lifted.
    if ( !isSelecting() ) {
        if (event.mouseButton() == MEvent::kMiddleMouse)
        {
            event.getPosition( endPos_x, endPos_y );

            // Delete the move command if we have moved less then 2 pixels
            // otherwise call finalize to set up the journal and add the
            // command to the undo queue.
            //
            if ( abs(startPos_x - endPos_x) < 2 ) {
                delete cmd;
                view.refresh( true );
            }
            else {
                stat = cmd->finalize();
                view.refresh( true );
            }
            setCursor(MCursor::defaultCursor);
        }
    }

    return stat;
}

void updateManipulators(void * data)
{
//
// Description
//     This callback function is called when the selection changes so that the manip can
//    be reinitialized on the new current selection.
//
    MStatus stat = MStatus::kSuccess;
    
    // Delete any previously existing manipulators.
    customAttrCtx * ctxPtr = (customAttrCtx *) data;
    ctxPtr->deleteManipulators(); 

    // iterate through the selected objects:
    // 
    MSelectionList list;
    stat = MGlobal::getActiveSelectionList(list);
    MItSelectionList iter(list, MFn::kInvalid, &stat);

    if (MS::kSuccess == stat) {
        for (; !iter.isDone(); iter.next()) {
            // create the customAttrManip2 for each object selected:
            //
            MString manipName ("customAttrManip2");
            MObject manipObject;
            ctxPtr->caManip = (customAttrManip2 *) customAttrManip2::newManipulator(manipName, manipObject);

            if (NULL != ctxPtr->caManip) {

                MObject dependNode;
                iter.getDependNode(dependNode);
                MFnDependencyNode dependNodeFn(dependNode);

                ctxPtr->addManipulator(manipObject);

                dependNodeFn.findPlug(customAttributeString,  true,  &stat);
                if (MStatus::kSuccess != stat) {
                    ctxPtr->deleteManipulators(); 
                    return;
                }

                ctxPtr->caManip->connectToDependNode(dependNode);
            } 
        }
    }
}


MStatus customAttrCtx::doEnterRegion(MEvent &event)
//
// Print the tool description in the help line.
//
{
    MString str(MOVEHELPSTR);
    return setHelpString(str);
}

//
// Context creation command
//
//  This is the command that will be used to create instances
//  of our context.
//
#define CREATE_CTX_NAME "customAttrManipContext2"


class customAttrCtxCommand : public MPxContextCommand
{
public:
    customAttrCtxCommand() {};
    MPxContext * makeObj() override;

public:
    static void* creator();
};


MPxContext *customAttrCtxCommand::makeObj()
{
    customAttrCtx *newC = new customAttrCtx();
    return newC;
}


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


//
// The following routines are used to register/unregister
// the commands we are creating within Maya
//
MStatus initializePlugin(MObject obj)
{
    MStatus status;
    MFnPlugin plugin(obj, PLUGIN_COMPANY, "3.0", "Any");

    status = plugin.registerContextCommand(
            CREATE_CTX_NAME, &customAttrCtxCommand::creator,
            ATTR_CMD_NAME, &customAttrCmd::creator);
    if (!status) 
    {
        status.perror("registerContextCommand");
        return status;
    }

    status = plugin.registerContextCommand(
            CREATE_TRIAD_CTX_NAME, &customTriadCtxCommand::creator);
    if (!status) 
    {
        status.perror("registerContextCommand");
        return status;
    }


    // Classify the node as a transform.  This causes Viewport
    // 2.0 to treat the node the same way it treats a regular
    // transform node.
    const MString classification = "drawdb/geometry/transform/rockingTransform2";
    status = plugin.registerTransform(  "rockingTransform2", 
                                        rockingTransform2Node::id, 
                                        &rockingTransform2Node::creator, 
                                        &rockingTransform2Node::initialize,
                                        &rockingTransform2Matrix::creator,
                                        rockingTransform2Matrix::id,
                                        &classification);
    if (!status) {
        status.perror("registerNode");
        return status;
    }

    status = plugin.registerNode("customAttrManip2", customAttrManip2::id, 
                                 &customAttrManip2::creator, &customAttrManip2::initialize,
                                 MPxNode::kManipContainer);
    if (!status) 
    {
        status.perror("registerManip");
        return status;
    }

    status = plugin.registerNode("customTriadManip", customTriadManip::id, 
                                 &customTriadManip::creator, &customTriadManip::initialize,
                                 MPxNode::kManipContainer);
    if (!status) 
    {
        status.perror("registerManip");
        return status;
    }

    MPxManipContainer::addToManipConnectTable(customTriadManip::id); 

    // Register a callback for the PostToolChanged and SelectionChanged events.
    cid1 = MEventMessage::addEventCallback("PostToolChanged", eventCB, NULL, &status);
    cid2 = MEventMessage::addEventCallback("SelectionChanged", eventCB, NULL, &status);

    MGlobal::executeCommandOnIdle("customAttrManipContext2 myCustomAttrContext");
    MGlobal::executeCommandOnIdle("customTriadManipContext myCustomTriadContext");
    return status;
}


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

    // Unregister the event callbacks.
    MEventMessage::removeCallback(cid1);
    MEventMessage::removeCallback(cid2);

    MPxManipContainer::removeFromManipConnectTable(customTriadManip::id); 

    status = plugin.deregisterContextCommand(CREATE_CTX_NAME, ATTR_CMD_NAME);
    if (!status) {
        status.perror("deregisterContextCommand");
        return status;
    }

    status = plugin.deregisterContextCommand(CREATE_TRIAD_CTX_NAME);
    if (!status) {
        status.perror("deregisterContextCommand");
        return status;
    }

    status = plugin.deregisterNode(customAttrManip2::id);
    if (!status) {
        status.perror("deregisterManip");
        return status;
    }

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

    status = plugin.deregisterNode( rockingTransform2Node::id );
    if (!status) {
        status.perror("deregisterNode");
        return status;
    }

    return status;
}

//
// Callback functions
//

//
// This callback gets called for the PostToolChanged and SelectionChanged events.
// It checks to see if the current context is the dragAttrContext, which is the context
// applied by default when a custom numeric attribute is selected in the channel box.
// In this case, the customAttrManip2 context is set.
// 
static void eventCB(void * data)
{
    // This check prevents recursion from happening when overriding the manip.
    if (isSetting)
        return;

    MSelectionList selList;
    MGlobal::getActiveSelectionList(selList);

    MString curCtx = "";
    MGlobal::executeCommand("currentCtx", curCtx);

    MDagPath path;
    MObject dependNode;
    for (unsigned int i=0; i<selList.length(); i++)
    {
        if ((selList.getDependNode(i, dependNode)) == MStatus::kSuccess)
        {
            MFnTransform node;
            if (node.hasObj(dependNode))
                node.setObject(dependNode);
            else
                continue;

            if (node.typeId() == rockingTransform2Node::id)
            {
                // If the current context is the dragAttrContext, check to see
                // if the custom channel box attributes are selected.  If so,
                // attach the custom manipulator.
                if ((curCtx == "dragAttrContext") || (curCtx == ""))
                {
                    // Make sure that the correct channel box attributes are selected
                    // before setting the tool context.
                    unsigned int c;
                    MStringArray cboxAttrs;
                    MGlobal::executeCommand(
                            "channelBox -q -selectedMainAttributes $gChannelBoxName", cboxAttrs);
                    for (c=0; c<cboxAttrs.length(); c++)
                    {
                        if (cboxAttrs[c] == customAttributeString)
                        {
                            isSetting = true;
                            MGlobal::executeCommand("setToolTo myCustomAttrContext");
                            isSetting = false;
                            return;
                        }
                    }
                }
                if ((curCtx == "moveSuperContext") || (curCtx == "manipMoveContext") ||
                    (curCtx == ""))
                {
                    isSetting = true;
                    MGlobal::executeCommand("setToolTo myCustomTriadContext");
                    isSetting = false;
                    return;
                }
            }
        }
    }
}