src/Gui/Selection/SoFCSelection.cpp

// SPDX-License-Identifier: LGPL-2.1-or-later
/***************************************************************************
 *   Copyright (c) 2005 Jürgen Riegel <juergen.riegel@web.de>              *
 *                                                                         *
 *   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 <QString>
#include <Inventor/SoFullPath.h>
#include <Inventor/SoPickedPoint.h>
#include <Inventor/actions/SoGLRenderAction.h>
#include <Inventor/actions/SoHandleEventAction.h>
#include <Inventor/details/SoFaceDetail.h>
#include <Inventor/details/SoLineDetail.h>
#include <Inventor/elements/SoLazyElement.h>
#include <Inventor/elements/SoMaterialBindingElement.h>
#include <Inventor/elements/SoOverrideElement.h>
#include <Inventor/elements/SoWindowElement.h>
#include <Inventor/events/SoKeyboardEvent.h>
#include <Inventor/events/SoLocation2Event.h>
#include <Inventor/events/SoMouseButtonEvent.h>
#include <Inventor/misc/SoState.h>


#include <Base/UnitsApi.h>

#include "SoFCSelection.h"
#include "MainWindow.h"
#include "SoFCSelectionAction.h"
#include "SoFCUnifiedSelection.h"
#include "ViewParams.h"


using namespace Gui;

namespace Gui
{
void printPreselectionInfo(
    const char* documentName,
    const char* objectName,
    const char* subElementName,
    float x,
    float y,
    float z,
    double precision
);
}

SoFullPath* Gui::SoFCSelection::currenthighlight = nullptr;


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

SO_NODE_SOURCE(SoFCSelection)

/*!
  Constructor.
*/
SoFCSelection::SoFCSelection()
{
    SO_NODE_CONSTRUCTOR(SoFCSelection);

    SO_NODE_ADD_FIELD(colorHighlight, (SbColor(0.8f, 0.1f, 0.1f)));
    SO_NODE_ADD_FIELD(colorSelection, (SbColor(0.1f, 0.8f, 0.1f)));
    SO_NODE_ADD_FIELD(style, (EMISSIVE));
    SO_NODE_ADD_FIELD(preselectionMode, (AUTO));
    SO_NODE_ADD_FIELD(selectionMode, (SEL_ON));
    SO_NODE_ADD_FIELD(selected, (NOTSELECTED));
    SO_NODE_ADD_FIELD(documentName, (""));
    SO_NODE_ADD_FIELD(objectName, (""));
    SO_NODE_ADD_FIELD(subElementName, (""));
    SO_NODE_ADD_FIELD(useNewSelection, (true));

    SO_NODE_DEFINE_ENUM_VALUE(Styles, EMISSIVE);
    SO_NODE_DEFINE_ENUM_VALUE(Styles, EMISSIVE_DIFFUSE);
    SO_NODE_DEFINE_ENUM_VALUE(Styles, BOX);
    SO_NODE_SET_SF_ENUM_TYPE(style, Styles);

    SO_NODE_DEFINE_ENUM_VALUE(PreselectionModes, AUTO);
    SO_NODE_DEFINE_ENUM_VALUE(PreselectionModes, ON);
    SO_NODE_DEFINE_ENUM_VALUE(PreselectionModes, OFF);
    SO_NODE_SET_SF_ENUM_TYPE(preselectionMode, PreselectionModes);

    SO_NODE_DEFINE_ENUM_VALUE(SelectionModes, SEL_ON);
    SO_NODE_DEFINE_ENUM_VALUE(SelectionModes, SEL_OFF);
    SO_NODE_SET_SF_ENUM_TYPE(selectionMode, SelectionModes);

    SO_NODE_DEFINE_ENUM_VALUE(Selected, NOTSELECTED);
    SO_NODE_DEFINE_ENUM_VALUE(Selected, SELECTED);
    SO_NODE_SET_SF_ENUM_TYPE(selected, Selected);

    highlighted = false;
    bShift = false;
    bCtrl = false;

    selected = NOTSELECTED;

    useNewSelection = ViewParams::instance()->getUseNewSelection();
    selContext = std::make_shared<SelContext>();
    selContext2 = std::make_shared<SelContext>();
}

/*!
  Destructor.
*/
SoFCSelection::~SoFCSelection()
{
    // If we're being deleted and we're the current highlight,
    // NULL out that variable
    if (currenthighlight
        && (!currenthighlight->getTail()->isOfType(SoFCSelection::getClassTypeId()))) {
        currenthighlight->unref();
        currenthighlight = nullptr;
    }
    // delete THIS;
}

// doc from parent
void SoFCSelection::initClass()
{
    SO_NODE_INIT_CLASS(SoFCSelection, SoGroup, "Group");
}

void SoFCSelection::finish()
{
    atexit_cleanup();
}

/*!
  Static method that can be used to turn off the current highlight.
*/
void SoFCSelection::turnOffCurrentHighlight(SoGLRenderAction* action)
{
    SoFCSelection::turnoffcurrent(action);
}

void SoFCSelection::doAction(SoAction* action)
{
    if (useNewSelection.getValue() && action->getCurPathCode() != SoAction::OFF_PATH) {
        if (action->getTypeId() == Gui::SoHighlightElementAction::getClassTypeId()) {
            auto hlaction = static_cast<Gui::SoHighlightElementAction*>(action);
            if (!hlaction->isHighlighted()) {
                auto ctx = Gui::SoFCSelectionRoot::getActionContext(action, this, selContext, false);
                if (ctx && ctx->isHighlighted()) {
                    ctx->highlightIndex = -1;
                    touch();
                }
            }
            else {
                auto ctx = Gui::SoFCSelectionRoot::getActionContext(action, this, selContext);
                if (ctx) {
                    ctx->highlightColor = hlaction->getColor();
                    if (!ctx->isHighlighted()) {
                        ctx->highlightIndex = 0;
                        touch();
                    }
                }
            }
            return;
        }
        else if (action->getTypeId() == Gui::SoSelectionElementAction::getClassTypeId()) {
            auto selaction = static_cast<Gui::SoSelectionElementAction*>(action);
            if (selaction->getType() == Gui::SoSelectionElementAction::All
                || selaction->getType() == Gui::SoSelectionElementAction::Append) {
                SelContextPtr ctx = Gui::SoFCSelectionRoot::getActionContext(action, this, selContext);
                if (ctx) {
                    ctx->selectionColor = selaction->getColor();
                    if (!ctx->isSelectAll()) {
                        ctx->selectAll();
                        this->touch();
                    }
                }
            }
            else if (selaction->getType() == Gui::SoSelectionElementAction::None
                     || selaction->getType() == Gui::SoSelectionElementAction::Remove) {
                SelContextPtr ctx
                    = Gui::SoFCSelectionRoot::getActionContext(action, this, selContext, false);
                if (ctx && ctx->isSelected()) {
                    ctx->selectionIndex.clear();
                    this->touch();
                }
            }
            return;
        }
    }

    if (action->getTypeId() == SoFCDocumentAction::getClassTypeId()) {
        auto docaction = static_cast<SoFCDocumentAction*>(action);
        this->documentName = docaction->documentName;
    }

    if (action->getTypeId() == SoFCDocumentObjectAction::getClassTypeId()) {
        auto objaction = static_cast<SoFCDocumentObjectAction*>(action);
        objaction->documentName = this->documentName.getValue();
        objaction->objectName = this->objectName.getValue();
        objaction->componentName = this->subElementName.getValue();
        objaction->setHandled();
    }

    if (!useNewSelection.getValue()) {

        if (action->getTypeId() == SoFCEnablePreselectionAction::getClassTypeId()) {
            auto preaction = static_cast<SoFCEnablePreselectionAction*>(action);
            if (preaction->enabled) {
                this->preselectionMode = SoFCSelection::AUTO;
            }
            else {
                this->preselectionMode = SoFCSelection::OFF;
            }
        }

        if (action->getTypeId() == SoFCEnableSelectionAction::getClassTypeId()) {
            auto selaction = static_cast<SoFCEnableSelectionAction*>(action);
            if (selaction->enabled) {
                this->selectionMode = SoFCSelection::SEL_ON;
            }
            else {
                this->selectionMode = SoFCSelection::SEL_OFF;
                if (selected.getValue() == SELECTED) {
                    this->selected = NOTSELECTED;
                }
            }
        }

        if (action->getTypeId() == SoFCSelectionColorAction::getClassTypeId()) {
            auto colaction = static_cast<SoFCSelectionColorAction*>(action);
            this->colorSelection = colaction->selectionColor;
        }

        if (action->getTypeId() == SoFCHighlightColorAction::getClassTypeId()) {
            auto colaction = static_cast<SoFCHighlightColorAction*>(action);
            this->colorHighlight = colaction->highlightColor;
        }

        if (selectionMode.getValue() == SEL_ON
            && action->getTypeId() == SoFCSelectionAction::getClassTypeId()) {
            auto selaction = static_cast<SoFCSelectionAction*>(action);

            if (selaction->SelChange.Type == SelectionChanges::AddSelection
                || selaction->SelChange.Type == SelectionChanges::RmvSelection) {
                if (documentName.getValue() == selaction->SelChange.pDocName
                    && objectName.getValue() == selaction->SelChange.pObjectName
                    && (subElementName.getValue() == selaction->SelChange.pSubName
                        || *(selaction->SelChange.pSubName) == '\0')) {
                    if (selaction->SelChange.Type == SelectionChanges::AddSelection) {
                        if (selected.getValue() == NOTSELECTED) {
                            selected = SELECTED;
                        }
                    }
                    else {
                        if (selected.getValue() == SELECTED) {
                            selected = NOTSELECTED;
                        }
                    }
                    return;
                }
            }
            else if (selaction->SelChange.Type == SelectionChanges::ClrSelection) {
                if (documentName.getValue() == selaction->SelChange.pDocName
                    || strcmp(selaction->SelChange.pDocName, "") == 0) {
                    if (selected.getValue() == SELECTED) {
                        selected = NOTSELECTED;
                    }
                }
            }
            else if (selaction->SelChange.Type == SelectionChanges::SetSelection) {
                bool sel = Selection().isSelected(
                    documentName.getValue().getString(),
                    objectName.getValue().getString() /*,
                     subElementName.getValue().getString()*/
                );
                if (sel) {
                    if (selected.getValue() == NOTSELECTED) {
                        selected = SELECTED;
                    }
                }
                else {
                    if (selected.getValue() == SELECTED) {
                        selected = NOTSELECTED;
                    }
                }
            }
        }
    }

    inherited::doAction(action);
}

int SoFCSelection::getPriority(const SoPickedPoint* p)
{
    const SoDetail* detail = p->getDetail();
    if (!detail) {
        return 0;
    }
    if (detail->isOfType(SoFaceDetail::getClassTypeId())) {
        return 1;
    }
    if (detail->isOfType(SoLineDetail::getClassTypeId())) {
        return 2;
    }
    if (detail->isOfType(SoPointDetail::getClassTypeId())) {
        return 3;
    }
    return 0;
}

const SoPickedPoint* SoFCSelection::getPickedPoint(SoHandleEventAction* action) const
{
    // To identify the picking of lines in a concave area we have to
    // get all intersection points. If we have two or more intersection
    // points where the first is of a face and the second of a line with
    // almost similar coordinates we use the second point, instead.
    const SoPickedPointList& points = action->getPickedPointList();
    if (points.getLength() == 0) {
        return nullptr;
    }
    else if (points.getLength() == 1) {
        return points[0];
    }

    const SoPickedPoint* picked = points[0];

    int picked_prio = getPriority(picked);
    const SbVec3f& picked_pt = picked->getPoint();


    for (int i = 1; i < points.getLength(); i++) {
        const SoPickedPoint* cur = points[i];
        int cur_prio = getPriority(cur);
        const SbVec3f& cur_pt = cur->getPoint();

        if ((cur_prio > picked_prio) && picked_pt.equals(cur_pt, 0.01f)) {
            picked = cur;
            picked_prio = cur_prio;
        }
    }
    return picked;
}

// doc from parent
void SoFCSelection::handleEvent(SoHandleEventAction* action)
{
    if (useNewSelection.getValue()) {
        inherited::handleEvent(action);
        return;
    }

    static char buf[513];
    auto mymode = static_cast<PreselectionModes>(this->preselectionMode.getValue());
    const SoEvent* event = action->getEvent();

    // mouse move events for preselection
    if (event->isOfType(SoLocation2Event::getClassTypeId())) {
        // NOTE: If preselection is off then we do not check for a picked point because otherwise
        // this search may slow down extremely the system on really big data sets. In this case we
        // just check for a picked point if the data set has been selected.
        if (mymode == AUTO || mymode == ON) {
            const SoPickedPoint* pp = this->getPickedPoint(action);
            if (pp && pp->getPath()->containsPath(action->getCurPath())) {
                if (!highlighted) {
                    if (Gui::Selection().setPreselect(
                            documentName.getValue().getString(),
                            objectName.getValue().getString(),
                            subElementName.getValue().getString(),
                            pp->getPoint()[0],
                            pp->getPoint()[1],
                            pp->getPoint()[2]
                        )) {
                        SoFCSelection::turnoffcurrent(action);
                        SoFCSelection::currenthighlight = static_cast<SoFullPath*>(
                            action->getCurPath()->copy()
                        );
                        SoFCSelection::currenthighlight->ref();
                        highlighted = true;
                        this->touch();  // force scene redraw
                        this->redrawHighlighted(action, true);
                    }
                }

                const auto& pt = pp->getPoint();

                printPreselectionInfo(
                    documentName.getValue().getString(),
                    objectName.getValue().getString(),
                    subElementName.getValue().getString(),
                    pt[0],
                    pt[1],
                    pt[2],
                    1e-7
                );
            }
            else {  // picked point
                if (highlighted) {
                    if (mymode == AUTO) {
                        SoFCSelection::turnoffcurrent(action);
                    }
                    // FIXME: I think we should set 'highlighted' to false whenever no point is
                    // picked else
                    highlighted = false;
                    Gui::Selection().rmvPreselect();
                }
            }
        }
    }  // key press events
    else if (event->isOfType(SoKeyboardEvent ::getClassTypeId())) {
        auto const e = static_cast<const SoKeyboardEvent*>(event);
        if (SoKeyboardEvent::isKeyPressEvent(e, SoKeyboardEvent::LEFT_SHIFT)
            || SoKeyboardEvent::isKeyPressEvent(e, SoKeyboardEvent::RIGHT_SHIFT)) {
            bShift = true;
        }
        if (SoKeyboardEvent::isKeyReleaseEvent(e, SoKeyboardEvent::LEFT_SHIFT)
            || SoKeyboardEvent::isKeyReleaseEvent(e, SoKeyboardEvent::RIGHT_SHIFT)) {
            bShift = false;
        }
        if (SoKeyboardEvent::isKeyPressEvent(e, SoKeyboardEvent::LEFT_CONTROL)
            || SoKeyboardEvent::isKeyPressEvent(e, SoKeyboardEvent::RIGHT_CONTROL)) {
            bCtrl = true;
        }
        if (SoKeyboardEvent::isKeyReleaseEvent(e, SoKeyboardEvent::LEFT_CONTROL)
            || SoKeyboardEvent::isKeyReleaseEvent(e, SoKeyboardEvent::RIGHT_CONTROL)) {
            bCtrl = false;
        }
    }  // mouse press events for (de)selection
    else if (event->isOfType(SoMouseButtonEvent::getClassTypeId())) {
        auto const e = static_cast<const SoMouseButtonEvent*>(event);
        if (SoMouseButtonEvent::isButtonReleaseEvent(e, SoMouseButtonEvent::BUTTON1)) {
            // FIXME: Shouldn't we remove the preselection for newly selected objects?
            //        Otherwise the tree signals that an object is preselected even though it is
            //        hidden. (Werner)
            const SoPickedPoint* pp = this->getPickedPoint(action);
            if (pp && pp->getPath()->containsPath(action->getCurPath())) {
                const auto& pt = pp->getPoint();
                if (bCtrl) {
                    if (Gui::Selection().isSelected(
                            documentName.getValue().getString(),
                            objectName.getValue().getString(),
                            subElementName.getValue().getString()
                        )) {
                        Gui::Selection().rmvSelection(
                            documentName.getValue().getString(),
                            objectName.getValue().getString(),
                            subElementName.getValue().getString()
                        );
                    }
                    else {
                        Gui::Selection().addSelection(
                            documentName.getValue().getString(),
                            objectName.getValue().getString(),
                            subElementName.getValue().getString(),
                            pt[0],
                            pt[1],
                            pt[2]
                        );

                        if (mymode == OFF) {
                            snprintf(
                                buf,
                                512,
                                "Selected: %s.%s.%s (%g, %g, %g)",
                                documentName.getValue().getString(),
                                objectName.getValue().getString(),
                                subElementName.getValue().getString(),
                                fabs(pt[0]) > 1e-7 ? pt[0] : 0.0,
                                fabs(pt[1]) > 1e-7 ? pt[1] : 0.0,
                                fabs(pt[2]) > 1e-7 ? pt[2] : 0.0
                            );

                            getMainWindow()->showMessage(QString::fromLatin1(buf));
                        }
                    }
                }
                else {  // Ctrl
                    if (!Gui::Selection().isSelected(
                            documentName.getValue().getString(),
                            objectName.getValue().getString(),
                            subElementName.getValue().getString()
                        )) {
                        Gui::Selection().clearSelection(documentName.getValue().getString());
                        Gui::Selection().addSelection(
                            documentName.getValue().getString(),
                            objectName.getValue().getString(),
                            subElementName.getValue().getString(),
                            pt[0],
                            pt[1],
                            pt[2]
                        );
                    }
                    else {
                        Gui::Selection().clearSelection(documentName.getValue().getString());
                        Gui::Selection().addSelection(
                            documentName.getValue().getString(),
                            objectName.getValue().getString(),
                            nullptr,
                            pt[0],
                            pt[1],
                            pt[2]
                        );
                    }

                    if (mymode == OFF) {
                        snprintf(
                            buf,
                            512,
                            "Selected: %s.%s.%s (%g, %g, %g)",
                            documentName.getValue().getString(),
                            objectName.getValue().getString(),
                            subElementName.getValue().getString(),
                            fabs(pt[0]) > 1e-7 ? pt[0] : 0.0,
                            fabs(pt[1]) > 1e-7 ? pt[1] : 0.0,
                            fabs(pt[2]) > 1e-7 ? pt[2] : 0.0
                        );

                        getMainWindow()->showMessage(QString::fromLatin1(buf));
                    }
                }

                action->setHandled();
            }  // picked point
        }  // mouse release
    }

    inherited::handleEvent(action);
}

// doc from parent
void SoFCSelection::GLRenderBelowPath(SoGLRenderAction* action)
{
    SoState* state = action->getState();
    SelContextPtr ctx = Gui::SoFCSelectionRoot::getRenderContext<SelContext>(this, selContext);
    if (selContext2->checkGlobal(ctx)) {
        ctx = selContext2;
    }
    if (!useNewSelection.getValue() && selContext == ctx) {
        ctx->selectionColor = this->colorSelection.getValue();
        ctx->highlightColor = this->colorHighlight.getValue();
        if (this->selected.getValue() == SELECTED) {
            ctx->selectAll();
        }
        else {
            ctx->selectionIndex.clear();
        }
        ctx->highlightIndex = this->highlighted ? 0 : -1;
    }

    // check if preselection is active
    if (this->setOverride(action, ctx)) {
        inherited::GLRenderBelowPath(action);
        state->pop();
    }
    else {
        inherited::GLRenderBelowPath(action);
    }
}

void SoFCSelection::GLRender(SoGLRenderAction* action)
{
    SoState* state = action->getState();
    SelContextPtr ctx = Gui::SoFCSelectionRoot::getRenderContext<SelContext>(this, selContext);
    if (selContext2->checkGlobal(ctx)) {
        ctx = selContext2;
    }
    if (!useNewSelection.getValue() && selContext == ctx) {
        ctx->selectionColor = this->colorSelection.getValue();
        ctx->highlightColor = this->colorHighlight.getValue();
        if (this->selected.getValue() == SELECTED) {
            ctx->selectAll();
        }
        else {
            ctx->selectionIndex.clear();
        }
        ctx->highlightIndex = this->highlighted ? 0 : -1;
    }

    // check if preselection is active
    if (this->setOverride(action, ctx)) {
        inherited::GLRender(action);
        state->pop();
    }
    else {
        inherited::GLRender(action);
    }
}

// doc from parent
void SoFCSelection::GLRenderInPath(SoGLRenderAction* action)
{
    SelContextPtr ctx = Gui::SoFCSelectionRoot::getRenderContext<SelContext>(this, selContext);
    if (selContext2->checkGlobal(ctx)) {
        ctx = selContext2;
    }
    if (!useNewSelection.getValue() && selContext == ctx) {
        ctx->selectionColor = this->colorSelection.getValue();
        ctx->highlightColor = this->colorHighlight.getValue();
        if (this->selected.getValue() == SELECTED) {
            ctx->selectAll();
        }
        else {
            ctx->selectionIndex.clear();
        }
        ctx->highlightIndex = this->highlighted ? 0 : -1;
    }
    // check if preselection is active
    SoState* state = action->getState();
    if (this->setOverride(action, ctx)) {
        inherited::GLRenderInPath(action);
        state->pop();
    }
    else {
        inherited::GLRenderInPath(action);
    }
}

SbBool SoFCSelection::preRender(SoGLRenderAction* action, GLint& oldDepthFunc)
//
////////////////////////////////////////////////////////////////////////
{
    // If not performing locate highlighting, just return.
    if (preselectionMode.getValue() == OFF) {
        return false;
    }

    SoState* state = action->getState();

    // ??? prevent caching at this level - for some reason the
    // ??? SoWindowElement::copyMatchInfo() method get called, which should
    // ??? never be called. We are not caching this node correctly yet....
    // SoCacheElement::invalidate(state);

    SbBool drawHighlighted
        = (preselectionMode.getValue() == ON || isHighlighted(action)
           || selected.getValue() == SELECTED);

    if (drawHighlighted) {
        // prevent diffuse & emissive color from leaking out...
        state->push();
        SbColor col;
        if (selected.getValue() == SELECTED) {
            col = colorSelection.getValue();
        }
        else {
            col = colorHighlight.getValue();
        }

        // Emissive Color
        SoLazyElement::setEmissive(state, &col);
        SoOverrideElement::setEmissiveColorOverride(state, this, true);

        // Diffuse Color
        if (style.getValue() == EMISSIVE_DIFFUSE) {
            SoLazyElement::setDiffuse(state, this, 1, &col, &colorpacker);
            SoOverrideElement::setDiffuseColorOverride(state, this, true);
        }
    }

    // Draw on top of other things at same z-buffer depth if:
    // [a] we're highlighted
    // [b] this is the highlighting pass. This occurs when changing from
    //     non-hilit to lit OR VICE VERSA.
    // Otherwise, leave it alone...
    if (drawHighlighted || highlighted) {
        glGetIntegerv(GL_DEPTH_FUNC, &oldDepthFunc);
        if (oldDepthFunc != GL_LEQUAL) {
            glDepthFunc(GL_LEQUAL);
        }
    }

    return drawHighlighted;
}

/*!
  Empty method in Coin. Can be used by subclasses to be told
  when status change.
*/
void SoFCSelection::redrawHighlighted(SoAction* action, SbBool doHighlight)
{
    Q_UNUSED(action);
    Q_UNUSED(doHighlight);
}

SbBool SoFCSelection::readInstance(SoInput* in, unsigned short flags)
{
    // Note: The read in document name can be false, so the caller must ensure pointing to the
    // correct document
    SbBool ret = inherited::readInstance(in, flags);
    return ret;
}
//
// update override state before rendering
//
bool SoFCSelection::setOverride(SoGLRenderAction* action, SelContextPtr ctx)
{
    auto mymode = static_cast<PreselectionModes>(this->preselectionMode.getValue());
    bool preselected = ctx && ctx->isHighlighted() && (useNewSelection.getValue() || mymode == AUTO);
    if (!preselected && mymode != ON && (!ctx || !ctx->isSelected())) {
        return false;
    }

    // uniqueId is returned by SoNode::getNodeId(). It is used to notify change
    // and for render cache update. In order to update cache on selection state
    // change, We manually change the id here by using a combined hash of the
    // original id and context pointer.
    auto oldId = this->uniqueId;
    this->uniqueId ^= std::hash<void*>()(ctx.get()) + 0x9e3779b9 + (oldId << 6) + (oldId >> 2);

    auto mystyle = static_cast<Styles>(this->style.getValue());

    if (mystyle == SoFCSelection::BOX) {
        if (ctx) {
            SoFCSelectionRoot::renderBBox(
                action,
                this,
                preselected ? ctx->highlightColor : ctx->selectionColor
            );
        }
        this->uniqueId = oldId;
        return false;
    }

    SoState* state = action->getState();
    state->push();

    SoMaterialBindingElement::set(state, SoMaterialBindingElement::OVERALL);
    SoOverrideElement::setMaterialBindingOverride(state, this, true);

    if (!preselected && ctx) {
        SoLazyElement::setEmissive(state, &ctx->selectionColor);
    }
    else if (ctx) {
        SoLazyElement::setEmissive(state, &ctx->highlightColor);
    }
    SoOverrideElement::setEmissiveColorOverride(state, this, true);

    if (SoLazyElement::getLightModel(state) == SoLazyElement::BASE_COLOR
        || mystyle == SoFCSelection::EMISSIVE_DIFFUSE) {
        if (!preselected && ctx) {
            SoLazyElement::setDiffuse(state, this, 1, &ctx->selectionColor, &colorpacker);
        }
        else if (ctx) {
            SoLazyElement::setDiffuse(state, this, 1, &ctx->highlightColor, &colorpacker);
        }
        SoOverrideElement::setDiffuseColorOverride(state, this, true);
    }

    this->uniqueId = oldId;
    return true;
}

// private convenience method
void SoFCSelection::turnoffcurrent(SoAction* action)
{
    if (SoFCSelection::currenthighlight && SoFCSelection::currenthighlight->getLength()) {
        SoNode* tail = SoFCSelection::currenthighlight->getTail();
        if (tail->isOfType(SoFCSelection::getClassTypeId())) {
            static_cast<SoFCSelection*>(tail)->highlighted = false;
            static_cast<SoFCSelection*>(tail)->touch();  // force scene redraw
            if (action) {
                static_cast<SoFCSelection*>(tail)->redrawHighlighted(action, false);
            }
        }
    }
    if (SoFCSelection::currenthighlight) {
        SoFCSelection::currenthighlight->unref();
        SoFCSelection::currenthighlight = nullptr;
    }
}

SbBool SoFCSelection::isHighlighted(SoAction* action)
//
////////////////////////////////////////////////////////////////////////
{
    auto actionPath = static_cast<const SoFullPath*>(action->getCurPath());
    return (
        currenthighlight && currenthighlight->getTail() == actionPath->getTail() &&  // nested SoHL!
        *currenthighlight == *actionPath
    );
}

void SoFCSelection::applySettings()
{
    // TODO Some view providers got copy of this code: make them use this (2015-09-03, Fat-Zer)
    // Note: SoFCUnifiedSelection got the same code, keep in sync or think about a way to share it
    float transparency;
    ParameterGrp::handle hGrp = Gui::WindowParameter::getDefaultParameter()->GetGroup("View");
    bool enablePre = hGrp->GetBool("EnablePreselection", true);
    bool enableSel = hGrp->GetBool("EnableSelection", true);
    if (!enablePre) {
        this->preselectionMode = Gui::SoFCSelection::OFF;
    }
    else {
        // Search for a user defined value with the current color as default
        SbColor highlightColor = this->colorHighlight.getValue();
        auto highlight = (unsigned long)(highlightColor.getPackedValue());
        highlight = hGrp->GetUnsigned("HighlightColor", highlight);
        highlightColor.setPackedValue((uint32_t)highlight, transparency);
        this->colorHighlight.setValue(highlightColor);
    }
    if (!enableSel) {
        this->selectionMode = Gui::SoFCSelection::SEL_OFF;
    }
    else {
        // Do the same with the selection color
        SbColor selectionColor = this->colorSelection.getValue();
        auto selection = (unsigned long)(selectionColor.getPackedValue());
        selection = hGrp->GetUnsigned("SelectionColor", selection);
        selectionColor.setPackedValue((uint32_t)selection, transparency);
        this->colorSelection.setValue(selectionColor);
    }
}