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