moveTool/moveTool.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 commands "moveToolCmd" and "moveToolContext".
// 
// Interactive tool for moving objects and components.
//
// This is an example of a selection-action tool. When nothing is selected,
// this tool behaves in exactly the same way as the selection tool in Maya. 
// Once an object is selected, the tool turns into a translation tool. 
//
// Note that at this time, the plug-in can translate:
//  
//  - transforms 
//  - NURBS curve CVs
//  - NURBS surface CVs 
//  - polygonal vertices 
//
// This plug-in will only perform translation in orthographic views. 
// Undo, redo, and journaling are supported by this tool.
//
// To use this plug-in:
//  (1) Execute the command "source moveTool". 
//      This creates a new entry in the "Shelf1" tab of the tool shelf called "moveTool".
//  (2) Click on the new icon, then select an object and drag it around in an orthographic view.
//      The left mouse button allows movement in two directions, while the middle mouse button
//      constrains the movement to a single direction. 
// 

#include <maya/MIOStream.h>
#include <stdio.h>
#include <stdlib.h>

#include <maya/MPxToolCommand.h>
#include <maya/MFnPlugin.h>
#include <maya/MArgList.h>
#include <maya/MGlobal.h>
#include <maya/MItSelectionList.h>
#include <maya/MPoint.h>
#include <maya/MVector.h>
#include <maya/MDagPath.h>

#include <maya/MFnTransform.h>
#include <maya/MItCurveCV.h>
#include <maya/MItSurfaceCV.h>
#include <maya/MItMeshVertex.h>

#include <maya/MPxSelectionContext.h>
#include <maya/MPxContextCommand.h>
#include <maya/M3dView.h>
#include <maya/MFnCamera.h>

#define CHECKRESULT(stat,msg)     \
    if ( MS::kSuccess != stat ) { \
        cerr << msg << endl;      \
    }

#define kVectorEpsilon 1.0e-3

//
// The move command
//
// - this is a tool command which can be used in tool
//   contexts or in the MEL command window.
//
#define     MOVENAME    "moveToolCmd"
#define     DOIT        0
#define     UNDOIT      1
#define     REDOIT      2

class moveCmd : public MPxToolCommand
{
public:
    moveCmd();
    ~moveCmd() 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        setVector( double x, double y, double z);
private:
    MVector     delta;  // the delta vectors
    MStatus     action( int flag ); // do the work here
};

moveCmd::moveCmd( )
{
    setCommandString( MOVENAME );
}

moveCmd::~moveCmd()
{}

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

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

void moveCmd::setVector( double x, double y, double z)
{
    delta.x = x;
    delta.y = y;
    delta.z = z;
}

MStatus moveCmd::finalize()
//
// Description
//     Command is finished, construct a string for the command
//     for journalling.
//
{
    MArgList command;
    command.addArg( commandString() );
    command.addArg( delta.x );
    command.addArg( delta.y );
    command.addArg( delta.z );

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

MStatus moveCmd::doIt( const MArgList& args )
//
// Description
//      Test MItSelectionList class
//
{
    MStatus stat;
    MVector vector( 1.0, 0.0, 0.0 );    // default delta
    unsigned i = 0;

    switch ( args.length() )     // set arguments to vector
    {
        case 1:
            vector.x = args.asDouble( 0, &stat );
            break;
        case 2:
            vector.x = args.asDouble( 0, &stat );
            vector.y = args.asDouble( 1, &stat );
            break;
        case 3:
            vector = args.asVector(i,3);
            break;
        case 0:
        default:
            break;
    }
    delta = vector;

    return action( DOIT );
}

MStatus moveCmd::undoIt( )
//
// Description
//      Undo last delta translation
//
{
    return action( UNDOIT );
}

MStatus moveCmd::redoIt( )
//
// Description
//      Redo last delta translation
//
{
    return action( REDOIT );
}

MStatus moveCmd::action( int flag )
//
// Description
//      Do the actual work here to move the objects by vector
//
{
    MStatus stat;
    MVector vector = delta;

    switch( flag )
    {
        case UNDOIT:    // undo
            vector.x = -vector.x;
            vector.y = -vector.y;
            vector.z = -vector.z;
            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
        MSpace::Space spc = MSpace::kWorld;

        // Translate 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 ) {
                stat = transFn.translateBy( vector, spc );
                CHECKRESULT(stat,"Error doing translate on transform");
                continue;
            }

            MItCurveCV cvFn( mdagPath, mComponent, &stat );
            if ( MS::kSuccess == stat ) {
                for ( ; !cvFn.isDone(); cvFn.next() ) {
                    stat = cvFn.translateBy( vector, spc );
                    CHECKRESULT(stat,"Error setting CV");
                }
                cvFn.updateCurve();
            }

            MItSurfaceCV sCvFn( mdagPath, mComponent, true, &stat );
            if ( MS::kSuccess == stat ) {
                for ( ; !sCvFn.isDone(); sCvFn.nextRow() ) {
                    for ( ; !sCvFn.isRowDone(); sCvFn.next() ) {
                        stat = sCvFn.translateBy( vector, spc );
                        CHECKRESULT(stat,"Error setting CV");
                    }
                }
                sCvFn.updateSurface();
            }

            MItMeshVertex vtxFn( mdagPath, mComponent, &stat );
            if ( MS::kSuccess == stat ) {
                for ( ; !vtxFn.isDone(); vtxFn.next() ) {
                    stat = vtxFn.translateBy( vector, spc );
                    CHECKRESULT(stat,"Error setting Vertex");
                }
                vtxFn.updateSurface();
            }
        } // for
    }
    else {
        cerr << "Error creating selection list iterator" << endl;
    }
    return MS::kSuccess;
}


//
// The moveTool Context
//
// - tool contexts are custom event handlers. The selection
//   context class defaults to maya's selection mode and
//   allows you to override press/drag/release events.
//
#define     MOVEHELPSTR        "drag to move selected object"
#define     MOVETITLESTR       "moveTool"
#define     TOP         0
#define     FRONT       1
#define     SIDE        2
#define     PERSP       3

class moveContext : public MPxSelectionContext
{
public:
    moveContext();
    void    toolOnSetup( MEvent & event ) override;
    MStatus doPress( MEvent & event ) override;
    MStatus doDrag( MEvent & event ) override;
    MStatus doRelease( MEvent & event ) override;
    MStatus doEnterRegion( MEvent & event ) override;

    /* override */
    MStatus doPress (MEvent & event, MHWRender::MUIDrawManager& drawMgr, const MHWRender::MFrameContext& context) override;
    /* override */
    MStatus doRelease( MEvent & event, MHWRender::MUIDrawManager& drawMgr, const MHWRender::MFrameContext& context) override;
    /* override */
    MStatus doDrag ( MEvent & event, MHWRender::MUIDrawManager& drawMgr, const MHWRender::MFrameContext& context) override;
    /* override */
    MStatus doHold ( MEvent & event, MHWRender::MUIDrawManager& drawMgr, const MHWRender::MFrameContext& context) override;
private:
    int currWin;
    MEvent::MouseButtonType downButton;
    M3dView view;
    short startPos_x, endPos_x, start_x, last_x;
    short startPos_y, endPos_y, start_y, last_y;
    moveCmd * cmd;
};


moveContext::moveContext()
{
    MString str( MOVETITLESTR );
    setTitleString( str );

    // Tell the context which XPM to use so the tool can properly
    // be a candidate for the 6th position on the mini-bar.
    setImage("moveTool.xpm", MPxContext::kImage1 );
}

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

/* just for test purpose. */
MStatus moveContext::doRelease( MEvent & event, MHWRender::MUIDrawManager& drawMgr, const MHWRender::MFrameContext& context)
{
    MStatus stat = doRelease( event ); // call VP1.0 version
    printf("- VP2.0 version doRelease() called.\n");
    return stat;
}
/* just for test purpose. */
MStatus moveContext::doDrag ( MEvent & event, MHWRender::MUIDrawManager& drawMgr, const MHWRender::MFrameContext& context)
{
    MStatus stat = doDrag( event ); // call VP1.0 version
    printf("- VP2.0 version doDrag() called.\n");
    return stat;
}
/* just for test purpose. */
MStatus moveContext::doHold ( MEvent & event, MHWRender::MUIDrawManager& drawMgr, const MHWRender::MFrameContext& context)
{
    printf("- VP2.0 version doHold() called.\n");
    return MStatus::kSuccess;
}

/* just for test purpose. */
MStatus moveContext::doPress (MEvent & event, MHWRender::MUIDrawManager& drawMgr, const MHWRender::MFrameContext& context)
{
    MStatus stat = doPress( event ); // call VP1.0 version
    printf("- VP2.0 version doPress() called.\n");
    return stat;
}

MStatus moveContext::doPress( MEvent & event )
{
    MStatus stat = MPxSelectionContext::doPress( event );
    MSpace::Space spc = MSpace::kWorld;

    // If we are not in selecting mode (i.e. an object has been selected)
    // then set up for the translation.
    //
    if ( !isSelecting() ) {
        event.getPosition( startPos_x, startPos_y );
        view = M3dView::active3dView();

        MDagPath camera;
        stat = view.getCamera( camera );
        if ( stat != MS::kSuccess ) {
            cerr << "Error: M3dView::getCamera" << endl;
            return stat;
        }
        MFnCamera fnCamera( camera );
        MVector upDir = fnCamera.upDirection( spc );
        MVector rightDir = fnCamera.rightDirection( spc );

        // Determine the camera used in the current view
        //
        if ( fnCamera.isOrtho() ) {
            if ( upDir.isEquivalent(MVector::zNegAxis,kVectorEpsilon) ) {
                currWin = TOP;
            } else if ( rightDir.isEquivalent(MVector::xAxis,kVectorEpsilon) ) {
                currWin = FRONT;
            } else  {
                currWin = SIDE;
            }
        }
        else {
            currWin = PERSP;
        }

        // Create an instance of the move tool command.
        //
        cmd = (moveCmd*)newToolCommand();

        cmd->setVector( 0.0, 0.0, 0.0 );
    }
    return stat;
}

MStatus moveContext::doDrag( MEvent & event )
{
    MStatus stat;
    stat = MPxSelectionContext::doDrag( event );

    // If we are not in selecting mode (i.e. an object has been selected)
    // then do the translation.
    //
    if ( !isSelecting() ) {
        event.getPosition( endPos_x, endPos_y );
        MPoint endW, startW;
        MVector vec;
        view.viewToWorld( startPos_x, startPos_y, startW, vec );
        view.viewToWorld( endPos_x, endPos_y, endW, vec );
        downButton = event.mouseButton();

        // We reset the the move vector each time a drag event occurs 
        // and then recalculate it based on the start position. 
        //
        cmd->undoIt();

        switch( currWin )
        {
            case TOP:
                switch ( downButton )
                {
                    case MEvent::kMiddleMouse :
                        cmd->setVector( endW.x - startW.x, 0.0, 0.0 );
                        break;
                    case MEvent::kLeftMouse :
                    default:
                        cmd->setVector( endW.x - startW.x, 0.0,
                                               endW.z - startW.z );
                        break;
                }
                break;  

            case FRONT:
                switch ( downButton )
                {
                    case MEvent::kMiddleMouse :
                        cmd->setVector( endW.x - startW.x, 0.0, 0.0 );
                        break;
                    case MEvent::kLeftMouse :
                    default:
                        cmd->setVector( endW.x - startW.x,
                                               endW.y - startW.y, 0.0 );
                        break;
                }
                break;  

            case SIDE:
                switch ( downButton )
                {
                    case MEvent::kMiddleMouse :
                        cmd->setVector( 0.0, 0.0, endW.z - startW.z );
                        break;
                    case MEvent::kLeftMouse :
                    default:
                        cmd->setVector( 0.0, endW.y - startW.y,
                                               endW.z - startW.z );
                        break;
                }
                break;  

            case PERSP:
                break;
        }

        stat = cmd->redoIt();
        view.refresh( true );
    }
    return stat;
}

MStatus moveContext::doRelease( MEvent & event )
{
    MStatus stat = MPxSelectionContext::doRelease( event );
    if ( !isSelecting() ) {
        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 && abs(startPos_y - endPos_y) < 2 ) {
            delete cmd;
            view.refresh( true );
        }
        else {
            stat = cmd->finalize();
            view.refresh( true );
        }
    }
    return stat;
}

MStatus moveContext::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 "moveToolContext"

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

public:
    static void* creator();
};

MPxContext * moveContextCommand::makeObj()
{
    return new moveContext();
}

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


//
// 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,
                                    &moveContextCommand::creator,
                                    MOVENAME, &moveCmd::creator );
    if (!status) {
        status.perror("registerContextCommand");
        return status;
    }

    return status;
}

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

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

    return status;
}