libreoffice/vcl/source/window/clipping.cxx

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/*
 * This file is part of the LibreOffice project.
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/.
 *
 * This file incorporates work covered by the following license notice:
 *
 *   Licensed to the Apache Software Foundation (ASF) under one or more
 *   contributor license agreements. See the NOTICE file distributed
 *   with this work for additional information regarding copyright
 *   ownership. The ASF licenses this file to you under the Apache
 *   License, Version 2.0 (the "License"); you may not use this file
 *   except in compliance with the License. You may obtain a copy of
 *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
 */

#include <vcl/window.hxx>

#include <sal/types.h>

#include <salobj.hxx>
#include <window.h>

void Window::InitClipRegion()
{
    DBG_TESTSOLARMUTEX();

    Region  aRegion;

    // Put back backed up background
    if ( mpWindowImpl->mpFrameData->mpFirstBackWin )
        ImplInvalidateAllOverlapBackgrounds();
    if ( mpWindowImpl->mbInPaint )
        aRegion = *(mpWindowImpl->mpPaintRegion);
    else
    {
        aRegion = *(ImplGetWinChildClipRegion());
        // --- RTL -- only this region is in frame coordinates, so re-mirror it
        // the mpWindowImpl->mpPaintRegion above is already correct (see ImplCallPaint()) !
        if( ImplIsAntiparallel() )
            ReMirror ( aRegion );
    }
    if ( mbClipRegion )
        aRegion.Intersect( ImplPixelToDevicePixel( maRegion ) );
    if ( aRegion.IsEmpty() )
        mbOutputClipped = true;
    else
    {
        mbOutputClipped = false;
        SelectClipRegion( aRegion );
    }
    mbClipRegionSet = true;

    mbInitClipRegion = false;
}

void Window::SetParentClipMode( sal_uInt16 nMode )
{

    if ( mpWindowImpl->mpBorderWindow )
        mpWindowImpl->mpBorderWindow->SetParentClipMode( nMode );
    else
    {
        if ( !ImplIsOverlapWindow() )
        {
            mpWindowImpl->mnParentClipMode = nMode;
            if ( nMode & PARENTCLIPMODE_CLIP )
                mpWindowImpl->mpParent->mpWindowImpl->mbClipChildren = true;
        }
    }
}

sal_uInt16 Window::GetParentClipMode() const
{

    if ( mpWindowImpl->mpBorderWindow )
        return mpWindowImpl->mpBorderWindow->GetParentClipMode();
    else
        return mpWindowImpl->mnParentClipMode;
}

void Window::ExpandPaintClipRegion( const Region& rRegion )
{
    if( mpWindowImpl->mpPaintRegion )
    {
        Region aPixRegion = LogicToPixel( rRegion );
        Region aDevPixRegion = ImplPixelToDevicePixel( aPixRegion );

        Region aWinChildRegion = *ImplGetWinChildClipRegion();
        // --- RTL -- only this region is in frame coordinates, so re-mirror it
        if( ImplIsAntiparallel() )
        {
            const OutputDevice *pOutDev = GetOutDev();
            pOutDev->ReMirror( aWinChildRegion );
        }

        aDevPixRegion.Intersect( aWinChildRegion );
        if( ! aDevPixRegion.IsEmpty() )
        {
            mpWindowImpl->mpPaintRegion->Union( aDevPixRegion );
            mbInitClipRegion = true;
        }
    }
}

Region Window::GetWindowClipRegionPixel( sal_uInt16 nFlags ) const
{

    Region aWinClipRegion;

    if ( nFlags & WINDOW_GETCLIPREGION_NOCHILDREN )
    {
        if ( mpWindowImpl->mbInitWinClipRegion )
            ((Window*)this)->ImplInitWinClipRegion();
        aWinClipRegion = mpWindowImpl->maWinClipRegion;
    }
    else
    {
        Region* pWinChildClipRegion = ((Window*)this)->ImplGetWinChildClipRegion();
        aWinClipRegion = *pWinChildClipRegion;
        // --- RTL --- remirror clip region before passing it to somebody
        if( ImplIsAntiparallel() )
        {
            const OutputDevice *pOutDev = GetOutDev();
            pOutDev->ReMirror( aWinClipRegion );
        }
    }

    if ( nFlags & WINDOW_GETCLIPREGION_NULL )
    {
        Rectangle   aWinRect( Point( mnOutOffX, mnOutOffY ), Size( mnOutWidth, mnOutHeight ) );
        Region      aWinRegion( aWinRect );

        if ( aWinRegion == aWinClipRegion )
            aWinClipRegion.SetNull();
    }

    aWinClipRegion.Move( -mnOutOffX, -mnOutOffY );

    return aWinClipRegion;
}


Region Window::GetActiveClipRegion() const
{
    Region aRegion(true);

    if ( mpWindowImpl->mbInPaint )
    {
        aRegion = *(mpWindowImpl->mpPaintRegion);
        aRegion.Move( -mnOutOffX, -mnOutOffY );
    }

    if ( mbClipRegion )
        aRegion.Intersect( maRegion );

    return PixelToLogic( aRegion );
}

void Window::ClipToPaintRegion(Rectangle& rDstRect)
{
    const Region aPaintRgn(GetPaintRegion());

    if (!aPaintRgn.IsNull())
        rDstRect.Intersection(LogicToPixel(aPaintRgn.GetBoundRect()));
}

void Window::EnableClipSiblings( bool bClipSiblings )
{

    if ( mpWindowImpl->mpBorderWindow )
        mpWindowImpl->mpBorderWindow->EnableClipSiblings( bClipSiblings );

    mpWindowImpl->mbClipSiblings = bClipSiblings;
}

void Window::ImplClipBoundaries( Region& rRegion, bool bThis, bool bOverlaps )
{
    if ( bThis )
        ImplIntersectWindowClipRegion( rRegion );
    else if ( ImplIsOverlapWindow() )
    {
        // clip to frame if required
        if ( !mpWindowImpl->mbFrame )
            rRegion.Intersect( Rectangle( Point( 0, 0 ), Size( mpWindowImpl->mpFrameWindow->mnOutWidth, mpWindowImpl->mpFrameWindow->mnOutHeight ) ) );

        if ( bOverlaps && !rRegion.IsEmpty() )
        {
            // Clip Overlap Siblings
            Window* pStartOverlapWindow = this;
            while ( !pStartOverlapWindow->mpWindowImpl->mbFrame )
            {
                Window* pOverlapWindow = pStartOverlapWindow->mpWindowImpl->mpOverlapWindow->mpWindowImpl->mpFirstOverlap;
                while ( pOverlapWindow && (pOverlapWindow != pStartOverlapWindow) )
                {
                    pOverlapWindow->ImplExcludeOverlapWindows2( rRegion );
                    pOverlapWindow = pOverlapWindow->mpWindowImpl->mpNext;
                }
                pStartOverlapWindow = pStartOverlapWindow->mpWindowImpl->mpOverlapWindow;
            }

            // Clip Child Overlap Windows
            ImplExcludeOverlapWindows( rRegion );
        }
    }
    else
        ImplGetParent()->ImplIntersectWindowClipRegion( rRegion );
}

bool Window::ImplClipChildren( Region& rRegion )
{
    bool    bOtherClip = false;
    Window* pWindow = mpWindowImpl->mpFirstChild;
    while ( pWindow )
    {
        if ( pWindow->mpWindowImpl->mbReallyVisible )
        {
            // read-out ParentClipMode-Flags
            sal_uInt16 nClipMode = pWindow->GetParentClipMode();
            if ( !(nClipMode & PARENTCLIPMODE_NOCLIP) &&
                 ((nClipMode & PARENTCLIPMODE_CLIP) || (GetStyle() & WB_CLIPCHILDREN)) )
                pWindow->ImplExcludeWindowRegion( rRegion );
            else
                bOtherClip = true;
        }

        pWindow = pWindow->mpWindowImpl->mpNext;
    }

    return bOtherClip;
}

void Window::ImplClipAllChildren( Region& rRegion )
{
    Window* pWindow = mpWindowImpl->mpFirstChild;
    while ( pWindow )
    {
        if ( pWindow->mpWindowImpl->mbReallyVisible )
            pWindow->ImplExcludeWindowRegion( rRegion );
        pWindow = pWindow->mpWindowImpl->mpNext;
    }
}

void Window::ImplClipSiblings( Region& rRegion )
{
    Window* pWindow = ImplGetParent()->mpWindowImpl->mpFirstChild;
    while ( pWindow )
    {
        if ( pWindow == this )
            break;

        if ( pWindow->mpWindowImpl->mbReallyVisible )
            pWindow->ImplExcludeWindowRegion( rRegion );

        pWindow = pWindow->mpWindowImpl->mpNext;
    }
}

void Window::ImplInitWinClipRegion()
{
    // Build Window Region
    mpWindowImpl->maWinClipRegion = Rectangle( Point( mnOutOffX, mnOutOffY ),
                                 Size( mnOutWidth, mnOutHeight ) );
    if ( mpWindowImpl->mbWinRegion )
        mpWindowImpl->maWinClipRegion.Intersect( ImplPixelToDevicePixel( mpWindowImpl->maWinRegion ) );

    // ClipSiblings
    if ( mpWindowImpl->mbClipSiblings && !ImplIsOverlapWindow() )
        ImplClipSiblings( mpWindowImpl->maWinClipRegion );

    // Clip Parent Boundaries
    ImplClipBoundaries( mpWindowImpl->maWinClipRegion, false, true );

    // Clip Children
    if ( (GetStyle() & WB_CLIPCHILDREN) || mpWindowImpl->mbClipChildren )
        mpWindowImpl->mbInitChildRegion = true;

    mpWindowImpl->mbInitWinClipRegion = false;
}

void Window::ImplInitWinChildClipRegion()
{
    if ( !mpWindowImpl->mpFirstChild )
    {
        if ( mpWindowImpl->mpChildClipRegion )
        {
            delete mpWindowImpl->mpChildClipRegion;
            mpWindowImpl->mpChildClipRegion = NULL;
        }
    }
    else
    {
        if ( !mpWindowImpl->mpChildClipRegion )
            mpWindowImpl->mpChildClipRegion = new Region( mpWindowImpl->maWinClipRegion );
        else
            *mpWindowImpl->mpChildClipRegion = mpWindowImpl->maWinClipRegion;

        ImplClipChildren( *mpWindowImpl->mpChildClipRegion );
    }

    mpWindowImpl->mbInitChildRegion = false;
}

Region* Window::ImplGetWinChildClipRegion()
{
    if ( mpWindowImpl->mbInitWinClipRegion )
        ImplInitWinClipRegion();
    if ( mpWindowImpl->mbInitChildRegion )
        ImplInitWinChildClipRegion();
    if ( mpWindowImpl->mpChildClipRegion )
        return mpWindowImpl->mpChildClipRegion;
    else
        return &mpWindowImpl->maWinClipRegion;
}


bool Window::ImplSysObjClip( const Region* pOldRegion )
{
    bool bUpdate = true;

    if ( mpWindowImpl->mpSysObj )
    {
        bool bVisibleState = mpWindowImpl->mbReallyVisible;

        if ( bVisibleState )
        {
            Region* pWinChildClipRegion = ImplGetWinChildClipRegion();

            if ( !pWinChildClipRegion->IsEmpty() )
            {
                if ( pOldRegion )
                {
                    Region aNewRegion = *pWinChildClipRegion;
                    pWinChildClipRegion->Intersect( *pOldRegion );
                    bUpdate = aNewRegion == *pWinChildClipRegion;
                }

                if ( mpWindowImpl->mpFrameData->mpFirstBackWin )
                    ImplInvalidateAllOverlapBackgrounds();

                Region      aRegion = *pWinChildClipRegion;
                Rectangle   aWinRect( Point( mnOutOffX, mnOutOffY ), Size( mnOutWidth, mnOutHeight ) );
                Region      aWinRectRegion( aWinRect );
                sal_uInt16      nClipFlags = mpWindowImpl->mpSysObj->GetClipRegionType();

                if ( aRegion == aWinRectRegion )
                    mpWindowImpl->mpSysObj->ResetClipRegion();
                else
                {
                    if ( nClipFlags & SAL_OBJECT_CLIP_EXCLUDERECTS )
                    {
                        aWinRectRegion.Exclude( aRegion );
                        aRegion = aWinRectRegion;
                    }
                    if ( !(nClipFlags & SAL_OBJECT_CLIP_ABSOLUTE) )
                        aRegion.Move( -mnOutOffX, -mnOutOffY );

                    // set/update clip region
                    RectangleVector aRectangles;
                    aRegion.GetRegionRectangles(aRectangles);
                    mpWindowImpl->mpSysObj->BeginSetClipRegion(aRectangles.size());

                    for(RectangleVector::const_iterator aRectIter(aRectangles.begin()); aRectIter != aRectangles.end(); ++aRectIter)
                    {
                        mpWindowImpl->mpSysObj->UnionClipRegion(
                            aRectIter->Left(),
                            aRectIter->Top(),
                            aRectIter->GetWidth(),   // orig nWidth was ((R - L) + 1), same as GetWidth does
                            aRectIter->GetHeight()); // same for height
                    }

                    mpWindowImpl->mpSysObj->EndSetClipRegion();
                }
            }
            else
                bVisibleState = false;
        }

        // update visible status
        mpWindowImpl->mpSysObj->Show( bVisibleState );
    }

    return bUpdate;
}

void Window::ImplUpdateSysObjChildrenClip()
{
    if ( mpWindowImpl->mpSysObj && mpWindowImpl->mbInitWinClipRegion )
        ImplSysObjClip( NULL );

    Window* pWindow = mpWindowImpl->mpFirstChild;
    while ( pWindow )
    {
        pWindow->ImplUpdateSysObjChildrenClip();
        pWindow = pWindow->mpWindowImpl->mpNext;
    }
}

void Window::ImplUpdateSysObjOverlapsClip()
{
    ImplUpdateSysObjChildrenClip();

    Window* pWindow = mpWindowImpl->mpFirstOverlap;
    while ( pWindow )
    {
        pWindow->ImplUpdateSysObjOverlapsClip();
        pWindow = pWindow->mpWindowImpl->mpNext;
    }
}

void Window::ImplUpdateSysObjClip()
{
    if ( !ImplIsOverlapWindow() )
    {
        ImplUpdateSysObjChildrenClip();

        // siblings should recalculate their clip region
        if ( mpWindowImpl->mbClipSiblings )
        {
            Window* pWindow = mpWindowImpl->mpNext;
            while ( pWindow )
            {
                pWindow->ImplUpdateSysObjChildrenClip();
                pWindow = pWindow->mpWindowImpl->mpNext;
            }
        }
    }
    else
        mpWindowImpl->mpFrameWindow->ImplUpdateSysObjOverlapsClip();
}

bool Window::ImplSetClipFlagChildren( bool bSysObjOnlySmaller )
{
    bool bUpdate = true;
    if ( mpWindowImpl->mpSysObj )
    {
        Region* pOldRegion = NULL;
        if ( bSysObjOnlySmaller && !mpWindowImpl->mbInitWinClipRegion )
            pOldRegion = new Region( mpWindowImpl->maWinClipRegion );

        mbInitClipRegion = true;
        mpWindowImpl->mbInitWinClipRegion = true;

        Window* pWindow = mpWindowImpl->mpFirstChild;
        while ( pWindow )
        {
            if ( !pWindow->ImplSetClipFlagChildren( bSysObjOnlySmaller ) )
                bUpdate = false;
            pWindow = pWindow->mpWindowImpl->mpNext;
        }

        if ( !ImplSysObjClip( pOldRegion ) )
        {
            mbInitClipRegion = true;
            mpWindowImpl->mbInitWinClipRegion = true;
            bUpdate = false;
        }

        delete pOldRegion;
    }
    else
    {
    mbInitClipRegion = true;
    mpWindowImpl->mbInitWinClipRegion = true;

    Window* pWindow = mpWindowImpl->mpFirstChild;
    while ( pWindow )
    {
        if ( !pWindow->ImplSetClipFlagChildren( bSysObjOnlySmaller ) )
            bUpdate = false;
        pWindow = pWindow->mpWindowImpl->mpNext;
    }
    }
    return bUpdate;
}

bool Window::ImplSetClipFlagOverlapWindows( bool bSysObjOnlySmaller )
{
    bool bUpdate = ImplSetClipFlagChildren( bSysObjOnlySmaller );

    Window* pWindow = mpWindowImpl->mpFirstOverlap;
    while ( pWindow )
    {
        if ( !pWindow->ImplSetClipFlagOverlapWindows( bSysObjOnlySmaller ) )
            bUpdate = false;
        pWindow = pWindow->mpWindowImpl->mpNext;
    }

    return bUpdate;
}

bool Window::ImplSetClipFlag( bool bSysObjOnlySmaller )
{
    if ( !ImplIsOverlapWindow() )
    {
        bool bUpdate = ImplSetClipFlagChildren( bSysObjOnlySmaller );

        Window* pParent = ImplGetParent();
        if ( pParent &&
             ((pParent->GetStyle() & WB_CLIPCHILDREN) || (mpWindowImpl->mnParentClipMode & PARENTCLIPMODE_CLIP)) )
        {
            pParent->mbInitClipRegion = true;
            pParent->mpWindowImpl->mbInitChildRegion = true;
        }

        // siblings should recalculate their clip region
        if ( mpWindowImpl->mbClipSiblings )
        {
            Window* pWindow = mpWindowImpl->mpNext;
            while ( pWindow )
            {
                if ( !pWindow->ImplSetClipFlagChildren( bSysObjOnlySmaller ) )
                    bUpdate = false;
                pWindow = pWindow->mpWindowImpl->mpNext;
            }
        }

        return bUpdate;
    }
    else
        return mpWindowImpl->mpFrameWindow->ImplSetClipFlagOverlapWindows( bSysObjOnlySmaller );
}

void Window::ImplIntersectWindowClipRegion( Region& rRegion )
{
    if ( mpWindowImpl->mbInitWinClipRegion )
        ImplInitWinClipRegion();

    rRegion.Intersect( mpWindowImpl->maWinClipRegion );
}

void Window::ImplIntersectWindowRegion( Region& rRegion )
{
    rRegion.Intersect( Rectangle( Point( mnOutOffX, mnOutOffY ),
                                  Size( mnOutWidth, mnOutHeight ) ) );
    if ( mpWindowImpl->mbWinRegion )
        rRegion.Intersect( ImplPixelToDevicePixel( mpWindowImpl->maWinRegion ) );
}

void Window::ImplExcludeWindowRegion( Region& rRegion )
{
    if ( mpWindowImpl->mbWinRegion )
    {
        Point aPoint( mnOutOffX, mnOutOffY );
        Region aRegion( Rectangle( aPoint,
                                   Size( mnOutWidth, mnOutHeight ) ) );
        aRegion.Intersect( ImplPixelToDevicePixel( mpWindowImpl->maWinRegion ) );
        rRegion.Exclude( aRegion );
    }
    else
    {
        Point aPoint( mnOutOffX, mnOutOffY );
        rRegion.Exclude( Rectangle( aPoint,
                                    Size( mnOutWidth, mnOutHeight ) ) );
    }
}

void Window::ImplExcludeOverlapWindows( Region& rRegion )
{
    Window* pWindow = mpWindowImpl->mpFirstOverlap;
    while ( pWindow )
    {
        if ( pWindow->mpWindowImpl->mbReallyVisible )
        {
            pWindow->ImplExcludeWindowRegion( rRegion );
            pWindow->ImplExcludeOverlapWindows( rRegion );
        }

        pWindow = pWindow->mpWindowImpl->mpNext;
    }
}

void Window::ImplExcludeOverlapWindows2( Region& rRegion )
{
    if ( mpWindowImpl->mbReallyVisible )
        ImplExcludeWindowRegion( rRegion );

    ImplExcludeOverlapWindows( rRegion );
}

void Window::ImplIntersectAndUnionOverlapWindows( const Region& rInterRegion, Region& rRegion )
{
    Window* pWindow = mpWindowImpl->mpFirstOverlap;
    while ( pWindow )
    {
        if ( pWindow->mpWindowImpl->mbReallyVisible )
        {
            Region aTempRegion( rInterRegion );
            pWindow->ImplIntersectWindowRegion( aTempRegion );
            rRegion.Union( aTempRegion );
            pWindow->ImplIntersectAndUnionOverlapWindows( rInterRegion, rRegion );
        }

        pWindow = pWindow->mpWindowImpl->mpNext;
    }
}

void Window::ImplIntersectAndUnionOverlapWindows2( const Region& rInterRegion, Region& rRegion )
{
    if ( mpWindowImpl->mbReallyVisible )
    {
        Region aTempRegion( rInterRegion );
        ImplIntersectWindowRegion( aTempRegion );
        rRegion.Union( aTempRegion );
    }

    ImplIntersectAndUnionOverlapWindows( rInterRegion, rRegion );
}

void Window::ImplCalcOverlapRegionOverlaps( const Region& rInterRegion, Region& rRegion )
{
    // Clip Overlap Siblings
    Window* pStartOverlapWindow;
    if ( !ImplIsOverlapWindow() )
        pStartOverlapWindow = mpWindowImpl->mpOverlapWindow;
    else
        pStartOverlapWindow = this;
    while ( !pStartOverlapWindow->mpWindowImpl->mbFrame )
    {
        Window* pOverlapWindow = pStartOverlapWindow->mpWindowImpl->mpOverlapWindow->mpWindowImpl->mpFirstOverlap;
        while ( pOverlapWindow && (pOverlapWindow != pStartOverlapWindow) )
        {
            pOverlapWindow->ImplIntersectAndUnionOverlapWindows2( rInterRegion, rRegion );
            pOverlapWindow = pOverlapWindow->mpWindowImpl->mpNext;
        }
        pStartOverlapWindow = pStartOverlapWindow->mpWindowImpl->mpOverlapWindow;
    }

    // Clip Child Overlap Windows
    if ( !ImplIsOverlapWindow() )
        mpWindowImpl->mpOverlapWindow->ImplIntersectAndUnionOverlapWindows( rInterRegion, rRegion );
    else
        ImplIntersectAndUnionOverlapWindows( rInterRegion, rRegion );
}

void Window::ImplCalcOverlapRegion( const Rectangle& rSourceRect, Region& rRegion,
                                    bool bChildren, bool bParent, bool bSiblings )
{
    Region  aRegion( rSourceRect );
    if ( mpWindowImpl->mbWinRegion )
        rRegion.Intersect( ImplPixelToDevicePixel( mpWindowImpl->maWinRegion ) );
    Region  aTempRegion;
    Window* pWindow;

    ImplCalcOverlapRegionOverlaps( aRegion, rRegion );

    // Parent-Boundaries
    if ( bParent )
    {
        pWindow = this;
        if ( !ImplIsOverlapWindow() )
        {
            pWindow = ImplGetParent();
            do
            {
                aTempRegion = aRegion;
                pWindow->ImplExcludeWindowRegion( aTempRegion );
                rRegion.Union( aTempRegion );
                if ( pWindow->ImplIsOverlapWindow() )
                    break;
                pWindow = pWindow->ImplGetParent();
            }
            while ( pWindow );
        }
        if ( pWindow && !pWindow->mpWindowImpl->mbFrame )
        {
            aTempRegion = aRegion;
            aTempRegion.Exclude( Rectangle( Point( 0, 0 ), Size( mpWindowImpl->mpFrameWindow->mnOutWidth, mpWindowImpl->mpFrameWindow->mnOutHeight ) ) );
            rRegion.Union( aTempRegion );
        }
    }

    // Siblings
    if ( bSiblings && !ImplIsOverlapWindow() )
    {
        pWindow = mpWindowImpl->mpParent->mpWindowImpl->mpFirstChild;
        do
        {
            if ( pWindow->mpWindowImpl->mbReallyVisible && (pWindow != this) )
            {
                aTempRegion = aRegion;
                pWindow->ImplIntersectWindowRegion( aTempRegion );
                rRegion.Union( aTempRegion );
            }
            pWindow = pWindow->mpWindowImpl->mpNext;
        }
        while ( pWindow );
    }

    if ( bChildren )
    {
        pWindow = mpWindowImpl->mpFirstChild;
        while ( pWindow )
        {
            if ( pWindow->mpWindowImpl->mbReallyVisible )
            {
                aTempRegion = aRegion;
                pWindow->ImplIntersectWindowRegion( aTempRegion );
                rRegion.Union( aTempRegion );
            }
            pWindow = pWindow->mpWindowImpl->mpNext;
        }
    }
}

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