src/graphics/PreviewedInset.C

   1 // -*- C++ -*-
   2 /**
   3  *  \file PreviewedInset.C
   4  *  Copyright 2002 the LyX Team
   5  *  Read the file COPYING
   6  *
   7  * \author Angus Leeming <leeming@lyx.org>
   8  */
   9
  10 #ifdef __GNUG__
  11 #pragma implementation
  12 #endif
  13
  14 #include <config.h>
  15
  16 #include "PreviewedInset.h"
  17
  18 #include "BufferView.h"
  19
  20 #include "GraphicsImage.h"
  21 #include "PreviewLoader.h"
  22 #include "PreviewImage.h"
  23 #include "Previews.h"
  24
  25 #include <boost/bind.hpp>
  26
  27
  28 namespace grfx {
  29
  30 bool PreviewedInset::activated()
  31 {
  32         return Previews::activated();
  33 }
  34
  35
  36 void PreviewedInset::generatePreview()
  37 {
  38         if (!Previews::activated() || !previewWanted() ||
  39             !view() || !view()->buffer())
  40                 return;
  41
  42         grfx::Previews & previews = grfx::Previews::get();
  43         grfx::PreviewLoader & loader = previews.loader(view()->buffer());
  44         addPreview(loader);
  45         loader.startLoading();
  46 }
  47
  48
  49 void PreviewedInset::addPreview(grfx::PreviewLoader & ploader)
  50 {
  51         if (!Previews::activated() || !previewWanted())
  52                 return;
  53
  54         snippet_ = latexString();
  55
  56         pimage_ = ploader.preview(snippet_);
  57         if (pimage_)
  58                 return;
  59
  60         // If this is the first time of calling, connect to the
  61         // grfx::PreviewLoader signal that'll inform us when the preview image
  62         // is ready for loading.
  63         if (!connection_.connected()) {
  64                 connection_ = ploader.connect(
  65                         boost::bind(&PreviewedInset::imageReady, this, _1));
  66         }
  67
  68         ploader.add(snippet_);
  69 }
  70
  71
  72 bool PreviewedInset::previewReady() const
  73 {
  74         if (!grfx::Previews::activated() || !previewWanted() ||
  75             !view() || !view()->buffer())
  76                 return false;
  77
  78         if (!pimage_ || snippet_ != pimage_->snippet()) {
  79                 grfx::PreviewLoader & ploader =
  80                         grfx::Previews::get().loader(view()->buffer());
  81                 pimage_ = ploader.preview(snippet_);
  82         }
  83
  84         if (!pimage_)
  85                 return false;
  86
  87         return pimage_->image(inset_, *view());
  88 }
  89
  90
  91 void PreviewedInset::imageReady(grfx::PreviewImage const & pimage) const
  92 {
  93         // Check snippet against the Inset's current contents
  94         if (snippet_ != pimage.snippet())
  95                 return;
  96
  97         pimage_ = &pimage;
  98         if (view())
  99                 view()->updateInset(&inset_, false);
 100 }
 101
 102 } // namespace grfx