sd/source/ui/inc/PreviewRenderer.hxx

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /*
   3  * This file is part of the LibreOffice project.
   4  *
   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 #pragma once
  21
  22 #include <vcl/image.hxx>
  23 #include <memory>
  24
  25 #include <svl/lstner.hxx>
  26
  27 class SdPage;
  28 class VirtualDevice;
  29
  30 namespace sd {
  31
  32 class DrawDocShell;
  33 class DrawView;
  34
  35 class PreviewRenderer final
  36     : public SfxListener
  37 {
  38 public:
  39     /** Create a new preview renderer that takes some of its initial values
  40         from the given output device.
  41         @param bPaintFrame
  42             When <TRUE/> (the default) then a frame is painted around the
  43             preview.  This makes the actual preview smaller.
  44     */
  45     PreviewRenderer(const bool bPaintFrame = true);
  46
  47     virtual ~PreviewRenderer() override;
  48
  49     /** Render a page with the given pixel size.
  50         Use this version when only the width of the preview is known to the
  51         caller. The height is then calculated according to the aspect
  52         ratio of the given page.
  53         @param pPage
  54             The page to render.
  55         @param nWidth
  56             The width of the preview in device coordinates.
  57          The high contrast mode of the application is
  58          ignored and the preview is rendered in normal mode.
  59     */
  60     Image RenderPage (
  61         const SdPage* pPage,
  62         const sal_Int32 nWidth);
  63
  64     /** Render a page with the given pixel size.
  65         @param pPage
  66             The page to render.
  67         @param aPreviewPixelSize
  68             The size in device coordinates of the preview.
  69         @param bObeyHighContrastMode
  70             When <FALSE/> then the high contrast mode of the application is
  71             ignored and the preview is rendered in normal mode.  When
  72             <TRUE/> and high contrast mode is active then the preview is
  73             rendered in high contrast mode.
  74         @param bDisplayPresentationObjects
  75             When <FALSE/> then the PresObj place holders are not displayed
  76             in the returned preview.
  77     */
  78     Image RenderPage (
  79         const SdPage* pPage,
  80         const Size aPreviewPixelSize,
  81         const bool bObeyHighContrastMode,
  82         const bool bDisplayPresentationObjects = true);
  83
  84     /** Render an image that contains the given substitution text instead of a
  85         slide preview.
  86         @param aPreviewPixelSize
  87             The size in device coordinates of the image.
  88     */
  89     Image RenderSubstitution (
  90         const Size& rPreviewPixelSize,
  91         const OUString& sSubstitutionText);
  92
  93     /** Scale the given bitmap by keeping its aspect ratio to the desired
  94         width.  Add a frame to it afterwards.
  95     */
  96     Image ScaleBitmap (
  97         const BitmapEx& rBitmap,
  98         int nWidth);
  99
 100 protected:
 101     virtual void Notify(SfxBroadcaster& rBC, const SfxHint& rHint) override;
 102
 103 private:
 104     ScopedVclPtr<VirtualDevice> mpPreviewDevice;
 105     ::std::unique_ptr<DrawView> mpView;
 106     DrawDocShell* mpDocShellOfView;
 107     const Color maFrameColor;
 108     const bool mbHasFrame;
 109     static const int snSubstitutionTextSize;
 110     // Width of the frame that is painted around the preview.
 111     static const int snFrameWidth;
 112
 113     bool Initialize (
 114         const SdPage* pPage,
 115         const Size& rPixelSize,
 116         const bool bObeyHighContrastMode);
 117     void PaintPage (
 118         const SdPage* pPage,
 119         const bool bDisplayPresentationObjects);
 120     void PaintSubstitutionText (const OUString& rSubstitutionText);
 121     void PaintFrame();
 122
 123     /** Set up the map mode so that the given page is renderer into a bitmap
 124         with the specified width.
 125         @param rPage
 126             The page for which the preview is created.
 127         @param rPixelSize
 128             The size of the resulting preview bitmap.  Note that this size
 129             includes the frame.  The actual preview is smaller accordingly.
 130      */
 131     void SetupOutputSize (const SdPage& rPage, const Size& rPixelSize);
 132
 133     /** When mpView is empty then create a new view and initialize it.
 134         Otherwise just initialize it.
 135     */
 136     void ProvideView (DrawDocShell* pDocShell);
 137 };
 138
 139 } // end of namespace ::sd
 140
 141 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */