canvas/source/vcl/bitmapbackbuffer.cxx

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /*
   3  * This file is part of the LibreOffice project.
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   5  * This Source Code Form is subject to the terms of the Mozilla Public
   6  * License, v. 2.0. If a copy of the MPL was not distributed with this
   7  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
   8  *
   9  * This file incorporates work covered by the following license notice:
  10  *
  11  *   Licensed to the Apache Software Foundation (ASF) under one or more
  12  *   contributor license agreements. See the NOTICE file distributed
  13  *   with this work for additional information regarding copyright
  14  *   ownership. The ASF licenses this file to you under the Apache
  15  *   License, Version 2.0 (the "License"); you may not use this file
  16  *   except in compliance with the License. You may obtain a copy of
  17  *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
  18  */
  19
  20 #include <sal/config.h>
  21
  22 #include <osl/diagnose.h>
  23 #include <vcl/bitmapex.hxx>
  24 #include <vcl/svapp.hxx>
  25
  26 #include "bitmapbackbuffer.hxx"
  27 #include "impltools.hxx"
  28
  29 namespace vclcanvas
  30 {
  31     BitmapBackBuffer::BitmapBackBuffer( const BitmapEx&         rBitmap,
  32                                         const OutputDevice&     rRefDevice ) :
  33         maBitmap( rBitmap ),
  34         mpVDev( nullptr ),
  35         mrRefDevice( rRefDevice ),
  36         mbBitmapContentIsCurrent( false ),
  37         mbVDevContentIsCurrent( false )
  38     {
  39     }
  40
  41     BitmapBackBuffer::~BitmapBackBuffer()
  42     {
  43         // make sure solar mutex is held on deletion (other methods
  44         // are supposed to be called with already locked solar mutex)
  45         SolarMutexGuard aGuard;
  46
  47         mpVDev.disposeAndClear();
  48     }
  49
  50     OutputDevice& BitmapBackBuffer::getOutDev()
  51     {
  52         createVDev();
  53         updateVDev();
  54         return *mpVDev;
  55     }
  56
  57     const OutputDevice& BitmapBackBuffer::getOutDev() const
  58     {
  59         createVDev();
  60         updateVDev();
  61         return *mpVDev;
  62     }
  63
  64     void BitmapBackBuffer::clear()
  65     {
  66         // force current content to bitmap, make all transparent white
  67         getBitmapReference().Erase(COL_TRANSPARENT);
  68     }
  69
  70     BitmapEx& BitmapBackBuffer::getBitmapReference()
  71     {
  72         OSL_ENSURE( !mbBitmapContentIsCurrent || !mbVDevContentIsCurrent,
  73                     "BitmapBackBuffer::getBitmapReference(): Both bitmap and VDev are valid?!" );
  74
  75         if( mbVDevContentIsCurrent && mpVDev )
  76         {
  77             // VDev content is more current than bitmap - copy contents before!
  78             mpVDev->EnableMapMode( false );
  79             mpVDev->SetAntialiasing( AntialiasingFlags::Enable );
  80             const Point aEmptyPoint;
  81             *maBitmap = mpVDev->GetBitmapEx( aEmptyPoint,
  82                                              mpVDev->GetOutputSizePixel() );
  83         }
  84
  85         // client queries bitmap, and will possibly alter content -
  86         // next time, VDev needs to be updated
  87         mbBitmapContentIsCurrent = true;
  88         mbVDevContentIsCurrent   = false;
  89
  90         return *maBitmap;
  91     }
  92
  93     Size BitmapBackBuffer::getBitmapSizePixel() const
  94     {
  95         Size aSize = maBitmap->GetSizePixel();
  96
  97         if( mbVDevContentIsCurrent && mpVDev )
  98         {
  99             mpVDev->EnableMapMode( false );
 100             mpVDev->SetAntialiasing( AntialiasingFlags::Enable );
 101             aSize = mpVDev->GetOutputSizePixel();
 102         }
 103
 104         return aSize;
 105     }
 106
 107     void BitmapBackBuffer::createVDev() const
 108     {
 109         if( mpVDev )
 110             return;
 111
 112         // VDev not yet created, do it now. Create an alpha-VDev,
 113         // if bitmap has transparency.
 114         mpVDev = maBitmap->IsAlpha() ?
 115             VclPtr<VirtualDevice>::Create( mrRefDevice, DeviceFormat::WITH_ALPHA ) :
 116             VclPtr<VirtualDevice>::Create( mrRefDevice );
 117
 118         OSL_ENSURE( mpVDev,
 119                     "BitmapBackBuffer::createVDev(): Unable to create VirtualDevice" );
 120
 121         mpVDev->SetOutputSizePixel( maBitmap->GetSizePixel() );
 122
 123         tools::SetDefaultDeviceAntiAliasing( mpVDev );
 124     }
 125
 126     void BitmapBackBuffer::updateVDev() const
 127     {
 128         OSL_ENSURE( !mbBitmapContentIsCurrent || !mbVDevContentIsCurrent,
 129                     "BitmapBackBuffer::updateVDev(): Both bitmap and VDev are valid?!" );
 130
 131         if( mpVDev && mbBitmapContentIsCurrent )
 132         {
 133             // fill with bitmap content
 134             mpVDev->EnableMapMode( false );
 135             mpVDev->SetAntialiasing( AntialiasingFlags::Enable );
 136             const Point aEmptyPoint;
 137             mpVDev->DrawBitmapEx( aEmptyPoint, *maBitmap );
 138         }
 139
 140         // canvas queried the VDev, and will possibly paint into
 141         // it. Next time, bitmap must be updated
 142         mbBitmapContentIsCurrent = false;
 143         mbVDevContentIsCurrent   = true;
 144     }
 145 }
 146
 147 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */