src/insets/render_preview.C

   1 /**
   2  * \file render_preview.C
   3  * This file is part of LyX, the document processor.
   4  * Licence details can be found in the file COPYING.
   5  *
   6  * \author Angus Leeming
   7  *
   8  * Full author contact details are available in file CREDITS.
   9  */
  10
  11 #include <config.h>
  12
  13 #include "insets/render_preview.h"
  14 #include "insets/inset.h"
  15
  16 #include "BufferView.h"
  17 #include "dimension.h"
  18 #include "gettext.h"
  19 #include "LColor.h"
  20 #include "metricsinfo.h"
  21
  22 #include "frontends/font_metrics.h"
  23 #include "frontends/Painter.h"
  24
  25 #include "graphics/PreviewImage.h"
  26 #include "graphics/PreviewLoader.h"
  27 #include "graphics/Previews.h"
  28
  29 #include "support/lstrings.h"
  30
  31 #include <boost/bind.hpp>
  32
  33 using std::string;
  34 using std::auto_ptr;
  35
  36 namespace graphics = lyx::graphics;
  37 namespace support  = lyx::support;
  38
  39
  40 bool RenderPreview::activated()
  41 {
  42         return graphics::Previews::activated();
  43 }
  44
  45
  46 RenderPreview::RenderPreview()
  47         : pimage_(0)
  48 {}
  49
  50
  51 RenderPreview::RenderPreview(RenderPreview const & other)
  52         : RenderBase(other),
  53           boost::signals::trackable(),
  54           snippet_(other.snippet_),
  55           pimage_(0)
  56 {}
  57
  58
  59 auto_ptr<RenderBase> RenderPreview::clone() const
  60 {
  61         return auto_ptr<RenderBase>(new RenderPreview(*this));
  62 }
  63
  64
  65 namespace {
  66
  67 string const statusMessage(BufferView const * bv, string const & snippet)
  68 {
  69         BOOST_ASSERT(bv && bv->buffer());
  70
  71         Buffer const & buffer = *bv->buffer();
  72         graphics::Previews const & previews = graphics::Previews::get();
  73         graphics::PreviewLoader const & loader = previews.loader(buffer);
  74         graphics::PreviewLoader::Status const status = loader.status(snippet);
  75
  76         string message;
  77         switch (status) {
  78         case graphics::PreviewLoader::InQueue:
  79         case graphics::PreviewLoader::Processing:
  80                 message = _("Preview loading");
  81                 break;
  82         case graphics::PreviewLoader::Ready:
  83                 message = _("Preview ready");
  84                 break;
  85         case graphics::PreviewLoader::NotFound:
  86                 message = _("Preview failed");
  87                 break;
  88         }
  89
  90         return message;
  91 }
  92
  93 } // namespace anon
  94
  95
  96 void RenderPreview::metrics(MetricsInfo & mi, Dimension & dim) const
  97 {
  98         if (previewReady()) {
  99                 dim.asc = pimage_->ascent();
 100                 dim.des = pimage_->descent();
 101                 dim.wid = pimage_->width();
 102         } else {
 103                 dim.asc = 50;
 104                 dim.des = 0;
 105
 106                 LyXFont font(mi.base.font);
 107                 font.setFamily(LyXFont::SANS_FAMILY);
 108                 font.setSize(LyXFont::SIZE_FOOTNOTE);
 109                 dim.wid = 15 +
 110                         font_metrics::width(statusMessage(mi.base.bv, snippet_),
 111                                             font);
 112         }
 113
 114         dim_ = dim;
 115 }
 116
 117
 118 void RenderPreview::draw(PainterInfo & pi, int x, int y) const
 119 {
 120         BOOST_ASSERT(pi.base.bv && pi.base.bv->buffer());
 121         Buffer const & buffer = *pi.base.bv->buffer();
 122         startLoading(buffer);
 123
 124         if (previewReady()) {
 125                 pi.pain.image(x, y - dim_.asc, dim_.wid, dim_.height(),
 126                               *(pimage_->image()));
 127                 return;
 128         }
 129
 130         pi.pain.rectangle(x + InsetOld::TEXT_TO_INSET_OFFSET,
 131                           y - dim_.asc,
 132                           dim_.wid - 2 * InsetOld::TEXT_TO_INSET_OFFSET,
 133                           dim_.asc + dim_.des,
 134                           LColor::foreground);
 135
 136         LyXFont font(pi.base.font);
 137         font.setFamily(LyXFont::SANS_FAMILY);
 138         font.setSize(LyXFont::SIZE_FOOTNOTE);
 139         pi.pain.text(x + InsetOld::TEXT_TO_INSET_OFFSET + 6,
 140                      y - font_metrics::maxAscent(font) - 4,
 141                      statusMessage(pi.base.bv, snippet_), font);
 142 }
 143
 144
 145 boost::signals::connection RenderPreview::connect(slot_type const & slot)
 146 {
 147         return preview_ready_signal_.connect(slot);
 148 }
 149
 150
 151 void RenderPreview::startLoading(Buffer const & buffer) const
 152 {
 153         if (!activated() && !snippet_.empty())
 154                 return;
 155
 156         graphics::Previews & previews = graphics::Previews::get();
 157         graphics::PreviewLoader & loader = previews.loader(buffer);
 158         loader.startLoading();
 159 }
 160
 161
 162 void RenderPreview::addPreview(string const & latex_snippet,
 163                                Buffer const & buffer)
 164 {
 165         if (!activated())
 166                 return;
 167
 168         graphics::Previews & previews = graphics::Previews::get();
 169         graphics::PreviewLoader & loader = previews.loader(buffer);
 170         addPreview(latex_snippet, loader);
 171 }
 172
 173
 174 void RenderPreview::addPreview(string const & latex_snippet,
 175                                graphics::PreviewLoader & ploader)
 176 {
 177         if (!activated())
 178                 return;
 179
 180         snippet_ = support::trim(latex_snippet);
 181         pimage_ = 0;
 182         if (snippet_.empty())
 183                 return;
 184
 185         pimage_ = ploader.preview(snippet_);
 186         if (pimage_)
 187                 return;
 188
 189         // If this is the first time of calling, connect to the
 190         // PreviewLoader signal that'll inform us when the preview image
 191         // is ready for loading.
 192         if (!ploader_connection_.connected()) {
 193                 ploader_connection_ = ploader.connect(
 194                         boost::bind(&RenderPreview::imageReady, this, _1));
 195         }
 196
 197         ploader.add(snippet_);
 198 }
 199
 200
 201 void RenderPreview::removePreview(Buffer const & buffer)
 202 {
 203         if (snippet_.empty())
 204                 return;
 205
 206         graphics::Previews & previews = graphics::Previews::get();
 207         graphics::PreviewLoader & loader = previews.loader(buffer);
 208         loader.remove(snippet_);
 209         snippet_.erase();
 210         pimage_ = 0;
 211 }
 212
 213
 214 bool RenderPreview::previewReady() const
 215 {
 216         return pimage_ ? pimage_->image() : false;
 217 }
 218
 219
 220 void RenderPreview::imageReady(graphics::PreviewImage const & pimage)
 221 {
 222         // Check the current snippet is the same as that previewed.
 223         if (snippet_ != pimage.snippet())
 224                 return;
 225
 226         pimage_ = &pimage;
 227         preview_ready_signal_();
 228 }
 229
 230
 231 void RenderMonitoredPreview::setAbsFile(string const & file)
 232 {
 233         monitor_.reset(file);
 234 }
 235
 236
 237 void RenderMonitoredPreview::draw(PainterInfo & pi, int x, int y) const
 238 {
 239         RenderPreview::draw(pi, x, y);
 240         if (!monitoring())
 241                 startMonitoring();
 242 }
 243
 244
 245 boost::signals::connection
 246 RenderMonitoredPreview::fileChanged(slot_type const & slot)
 247 {
 248         return monitor_.connect(slot);
 249 }