/***************************************************************************
 *   Copyright (c)2011  Luke Parry                                         *
 *                                                                         *
 *   This file is part of the FreeCAD CAx development system.              *
 *                                                                         *
 *   This library is free software; you can redistribute it and/or         *
 *   modify it under the terms of the GNU Library General Public           *
 *   License as published by the Free Software Foundation; either          *
 *   version 2 of the License, or (at your option) any later version.      *
 *                                                                         *
 *   This library  is distributed in the hope that it will be useful,      *
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
 *   GNU Library General Public License for more details.                  *
 *                                                                         *
 *   You should have received a copy of the GNU Library General Public     *
 *   License along with this library; see the file COPYING.LIB. If not,    *
 *   write to the Free Software Foundation, Inc., 59 Temple Place,         *
 *   Suite 330, Boston, MA  02111-1307, USA                                *
 *                                                                         *
 ***************************************************************************/

#include "PreCompiled.h"

#ifndef _PreComp_
# include <Inventor/actions/SoGLRenderAction.h>
# include <Inventor/misc/SoState.h>
# include <cmath>
# include <cfloat>
#endif

#include <Inventor/actions/SoGetMatrixAction.h>
#include <Inventor/actions/SoGLRenderAction.h>
#include <Inventor/elements/SoModelMatrixElement.h>
#include <Inventor/elements/SoProjectionMatrixElement.h>
#include <Inventor/elements/SoViewingMatrixElement.h>
#include <Inventor/elements/SoViewVolumeElement.h>
#include <Inventor/elements/SoViewportRegionElement.h>
#include <Inventor/nodes/SoCamera.h>


#include "SoAutoZoomTranslation.h"

// *************************************************************************

using namespace Gui;

// ------------------------------------------------------

SO_NODE_SOURCE(SoAutoZoomTranslation);

void SoAutoZoomTranslation::initClass()
{
    SO_NODE_INIT_CLASS(SoAutoZoomTranslation, SoTransformation, "AutoZoom");

    // Enable elements for SoGetMatrixAction (#0002268)
    // SoCamera::initClass() enables the SoViewVolumeElement for
    // * SoGLRenderAction
    // * SoGetBoundingBoxAction
    // * SoRayPickAction
    // * SoCallbackAction
    // * SoGetPrimitiveCountAction
    // The element SoViewportRegionElement is enabled by the
    // above listed actions.
    // Addionally, SoViewVolumeElement is enabled for
    // * SoAudioRenderAction
    // * SoHandleEventAction
    // And SoViewportRegionElement is enabled for
    // * SoHandleEventAction
    // * SoGetMatrixAction
    SO_ENABLE(SoGetMatrixAction, SoViewVolumeElement);
}

float SoAutoZoomTranslation::getScaleFactor(SoAction* action) const
{
    // Dividing by 5 seems to work well
    SbViewVolume vv = SoViewVolumeElement::get(action->getState());
    float aspectRatio = SoViewportRegionElement::get(action->getState()).getViewportAspectRatio();
    float scale = vv.getWorldToScreenScale(SbVec3f(0.f, 0.f, 0.f), 0.1f) / (5*aspectRatio);
    return scale;
}

SoAutoZoomTranslation::SoAutoZoomTranslation()
{
    SO_NODE_CONSTRUCTOR(SoAutoZoomTranslation);
    //SO_NODE_ADD_FIELD(abPos, (SbVec3f(0.f,0.f,0.f)));
}

void SoAutoZoomTranslation::GLRender(SoGLRenderAction * action)
{
    SoAutoZoomTranslation::doAction((SoAction *)action);
    inherited::GLRender(action);
}

// Doc in superclass.
void SoAutoZoomTranslation::doAction(SoAction * action)
{
    float sf = this->getScaleFactor(action);
    SoModelMatrixElement::scaleBy(action->getState(), this,
                                SbVec3f(sf,sf,sf));
}

// set the auto scale factor.
//void SoAutoZoomTranslation::setAutoScale(void)
//{
//    float sf = this->getScaleFactor();
//    //this->enableNotify	(	false );
//    scaleFactor.setValue(SbVec3f(sf,sf,sf));
//    //this->enableNotify	(	true );
//    //scaleFactor.setDirty (true);
//    
//}

void SoAutoZoomTranslation::getMatrix(SoGetMatrixAction * action)
{
    float sf = this->getScaleFactor(action);

    SbVec3f scalevec = SbVec3f(sf,sf,sf);
    SbMatrix m;

    m.setScale(scalevec);
    action->getMatrix().multLeft(m);

    m.setScale(SbVec3f(1.0f / scalevec[0], 1.0f / scalevec[1], 1.0f / scalevec[2]));
    action->getInverse().multRight(m);
}

void SoAutoZoomTranslation::callback(SoCallbackAction * action)
{
    SoAutoZoomTranslation::doAction((SoAction*)action);
}

void SoAutoZoomTranslation::getBoundingBox(SoGetBoundingBoxAction * action)
{
    SoAutoZoomTranslation::doAction((SoAction*)action);
}

void SoAutoZoomTranslation::pick(SoPickAction * action)
{
    SoAutoZoomTranslation::doAction((SoAction*)action);
}

// Doc in superclass.
void SoAutoZoomTranslation::getPrimitiveCount(SoGetPrimitiveCountAction * action)
{
    SoAutoZoomTranslation::doAction((SoAction*)action);
}