Changes the UI interface so that only the current page is rendered on screen at a time. This has significant memory benefits for large PDF files. This also implements a least-recently used cache of tunable size, which improves responsiveness if you're hopping between two specific pages.

1 files changed, 176 insertions, 113 deletions

diff --git a/src-qt5/desktop-utils/lumina-pdf/Renderer-poppler.cpp b/src-qt5/desktop-utils/lumina-pdf/Renderer-poppler.cpp
index 2b28d0c3..d90f36d3 100644
--- a/src-qt5/desktop-utils/lumina-pdf/Renderer-poppler.cpp
+++ b/src-qt5/desktop-utils/lumina-pdf/Renderer-poppler.cpp
@@ -1,82 +1,86 @@
 #include "Renderer.h"
-#include <poppler/qt5/poppler-qt5.h>
+#include "drawablepage.h"
+#include "link.h"
+#include "lrucache.h"
 #include <QThread>
+#include <atomic>
+#include <poppler/qt5/poppler-qt5.h>
 
-class Link {
-  public:
-    Link(TextData *_data, Poppler::Link *_link) : data(_data), link(_link) { }
-    ~Link() { delete data; }
-
-    TextData* getData() { return data; }
-    Poppler::Link* getLink() { return link; }
-
-  private:
-    TextData *data;
-    Poppler::Link *link;
-};
-
-static Poppler::Document *DOC;
+static std::unique_ptr<Poppler::Document> DOC;
 QHash<int, QImage> loadingHash;
-QHash<int, QList<Link*>> linkHash;
 
-Renderer::Renderer(){
-  DOC = 0;
-  needpass = false;
-  pnum = 0;
-	degrees = 0;
+static std::vector<LuminaPDF::drawablePage> pages;
+static std::vector<QList<LuminaPDF::Link *>> links;
+static std::atomic<int> pagesStillLoading;
+static QHash<int, QList<LuminaPDF::Link *>> linkHash;
+static LuminaPDF::LRUCache<QImage> imageCache;
+
+Renderer::Renderer() : pnum(0), needpass(false), degrees(0) {
+  DOC.reset(nullptr);
+  pagesStillLoading = 1;
+  imageCache.setCacheSize(5);
 }
 
-Renderer::~Renderer(){
-  //qDeleteAll(loadingHash);
+Renderer::~Renderer() {
+  // qDeleteAll(loadingHash);
+  pages.clear();
+  for (auto &linkList : links) {
+    qDeleteAll(linkList);
+  }
   loadingHash.clear();
 }
 
-bool Renderer::loadMultiThread(){ return true; }
+bool Renderer::loadMultiThread() { return true; }
 
 /*QJsonObject Renderer::properties(){
   return QJsonObject(); //TO-DO
 }*/
 
-bool Renderer::loadDocument(QString path, QString password){
-  //qDebug() << "Load Document:" << path;
-  if(DOC!=0 && path!=docpath){
-    //Clear out the old document first
-    delete DOC;
-    DOC=0;
-    if(linkHash.size() > 0) {
-      foreach(QList<Link*> linkArray, linkHash) {
+bool Renderer::loadDocument(QString path, QString password) {
+  // qDebug() << "Load Document:" << path;
+  if (DOC != nullptr && path != docpath) {
+    // Clear out the old document first
+    DOC.reset(nullptr);
+    pages.clear();
+    if (linkHash.size() > 0) {
+      foreach (QList<LuminaPDF::Link *> linkArray, linkHash) {
         qDeleteAll(linkArray);
       }
       linkHash.clear();
     }
     needpass = false;
-    pnum=0;
+    pnum = 0;
     docpath = path;
   }
-  //Load the Document (if needed);
-  if(DOC==0){
-    //qDebug() << "Loading Document";
-    DOC = Poppler::Document::load(path);
+  // Load the Document (if needed);
+  if (DOC == nullptr) {
+    // qDebug() << "Loading Document";
+    DOC.reset(Poppler::Document::load(path));
     docpath = path;
   }
 
-  if(DOC==0){
+  if (DOC == nullptr) {
     qDebug() << "Could not open file:" << path;
     return false;
-  }else if(DOC->isLocked()){
-    //qDebug() << "Document Locked";
+  }
+
+  if (DOC->isLocked()) {
+    // qDebug() << "Document Locked";
     needpass = true;
-    if(password.isEmpty()){ return false; } //stop here - need to get password from user before continuing
-    needpass = !DOC->unlock(QByteArray(), password.toLocal8Bit());
-    if(needpass){ return false; } //invalid password
+    if (password.isEmpty() or
+        !DOC->unlock(QByteArray(), password.toLocal8Bit())) {
+      return false;
+    } // invalid password
   }
-  //qDebug() << "Opening File:" << path;
+  // qDebug() << "Opening File:" << path;
   doctitle = DOC->title();
-  if(doctitle.isEmpty()){ doctitle = path.section("/",-1); }
+  if (doctitle.isEmpty()) {
+    doctitle = path.section("/", -1);
+  }
   pnum = DOC->numPages();
-  //Setup the Document
+  // Setup the Document
   Poppler::Page *PAGE = DOC->page(0);
-  if(PAGE!=0){
+  if (PAGE != 0) {
     /*switch(PAGE->orientation()){
       case Poppler::Page::Landscape:
         WIDGET->setOrientation(QPageLayout::Landscape); break;
@@ -84,62 +88,93 @@ bool Renderer::loadDocument(QString path, QString password){
         WIDGET->setOrientation(QPageLayout::Portrait);
     }*/
     delete PAGE;
-    return true; //could load the first page
+    pages.reserve(pnum + 1);
+
+    for (int i = 0; i < pnum + 1; ++i) {
+      LuminaPDF::drawablePage temp;
+      pages.emplace_back(std::move(temp));
+    }
+
+    for (int i = 0; i < pnum + 1; ++i) {
+      QList<LuminaPDF::Link *> temp;
+      links.push_back(temp);
+    }
+
+    pagesStillLoading = pnum;
+
+    return true; // could load the first page
   }
-  return false; //nothing to load
+  return false; // nothing to load
 }
 
-void Renderer::renderPage(int pagenum, QSize DPI, int degrees){
-  //qDebug() << "Render Page:" << pagenum << DPI << degrees;
+void Renderer::renderPage(int pagenum, QSize DPI, int degrees) {
+  // qDebug() << "Render Page:" << pagenum << DPI << degrees;
+
+  emit SetProgress(pages.size() - pagesStillLoading);
 
-  if(DOC!=0){
-    Poppler::Page *PAGE = DOC->page(pagenum);
+  if (DOC != nullptr) {
+    Poppler::Page *PAGE = DOC->page(pagenum - 1);
     QImage img;
-    if(PAGE!=0){
-			Poppler::Page::Rotation rotation;
-			switch(degrees) {
-				case 90:
-					rotation = Poppler::Page::Rotation::Rotate90;
-					break;
-				case 180:
-					rotation = Poppler::Page::Rotation::Rotate180;
-					break;
-				case 270:
-					rotation = Poppler::Page::Rotation::Rotate270;
-					break;
-				default:
-					rotation = Poppler::Page::Rotation::Rotate0;
-			}
-      img = PAGE->renderToImage(DPI.width(), DPI.height(), -1, -1, -1, -1, rotation);
-      loadingHash.insert(pagenum, img);
-      QList<Link*> linkArray;
-      foreach(Poppler::Link *link, PAGE->links()) {
+    if (PAGE != nullptr) {
+      Poppler::Page::Rotation rotation;
+      switch (degrees) {
+      case 90:
+        rotation = Poppler::Page::Rotation::Rotate90;
+        break;
+      case 180:
+        rotation = Poppler::Page::Rotation::Rotate180;
+        break;
+      case 270:
+        rotation = Poppler::Page::Rotation::Rotate270;
+        break;
+      default:
+        rotation = Poppler::Page::Rotation::Rotate0;
+      }
+
+      LuminaPDF::drawablePage temp(PAGE, DPI, rotation);
+      pages[pagenum] = std::move(temp);
+      // img = PAGE->renderToImage(DPI.width(), DPI.height(), -1, -1, -1, -1,
+      //                          rotation);
+      // loadingHash.insert(pagenum, img);
+      QList<LuminaPDF::Link *> linkArray;
+
+      foreach (Poppler::Link *link, PAGE->links()) {
         QString location;
-        if(link->linkType() == Poppler::Link::LinkType::Goto)
-          location = dynamic_cast<Poppler::LinkGoto*>(link)->fileName();
-        else if(link->linkType() == Poppler::Link::LinkType::Goto)
-          location = dynamic_cast<Poppler::LinkBrowse*>(link)->url();
-        Link *newLink = new Link(new TextData(link->linkArea(), pagenum, location), link);
+        if (link->linkType() == Poppler::Link::LinkType::Goto)
+          location = dynamic_cast<Poppler::LinkGoto *>(link)->fileName();
+        else if (link->linkType() == Poppler::Link::LinkType::Goto)
+          location = dynamic_cast<Poppler::LinkBrowse *>(link)->url();
+        LuminaPDF::Link *newLink = new LuminaPDF::Link(
+            new TextData(link->linkArea(), pagenum, location), link);
         linkArray.append(newLink);
       }
-      linkHash.insert(pagenum, linkArray);
-      delete PAGE;
+
+      links[pagenum] = linkArray;
+      // linkHash.insert(pagenum, linkArray);
     }
-    //qDebug() << "Done Render Page:" << pagenum << img.size();
-  }else{
-    loadingHash.insert(pagenum, QImage());
+    // qDebug() << "Done Render Page:" << pagenum << img.size();
+  } else {
+    pages[pagenum] = LuminaPDF::drawablePage();
+    // loadingHash.insert(pagenum, QImage());
   }
-  emit PageLoaded(pagenum);
+
+  if (pagesStillLoading == 1) {
+    emit PageLoaded();
+  }
+
+  --pagesStillLoading;
 }
 
-QList<TextData*> Renderer::searchDocument(QString text, bool matchCase){
-  QList<TextData*> results;
-  for(int i = 0; i < pnum; i++) {
-    QList<Poppler::TextBox*> textList = DOC->page(i)->textList();
-    for(int j = 0; j < textList.size(); j++) {
-      if(textList[j]->text().contains(text, 
-      (matchCase) ? Qt::CaseSensitive : Qt::CaseInsensitive)) {
-        TextData *t = new TextData(textList[j]->boundingBox(), i+1, text);
+bool Renderer::isDoneLoading() { return pagesStillLoading == 0; }
+
+QList<TextData *> Renderer::searchDocument(QString text, bool matchCase) {
+  QList<TextData *> results;
+  for (int i = 0; i < pnum; i++) {
+    QList<Poppler::TextBox *> textList = DOC->page(i)->textList();
+    for (int j = 0; j < textList.size(); j++) {
+      if (textList[j]->text().contains(
+              text, (matchCase) ? Qt::CaseSensitive : Qt::CaseInsensitive)) {
+        TextData *t = new TextData(textList[j]->boundingBox(), i + 1, text);
         results.append(t);
       }
     }
@@ -147,59 +182,87 @@ QList<TextData*> Renderer::searchDocument(QString text, bool matchCase){
   return results;
 }
 
+QSize Renderer::imageSize(int pagenum) { return pages[pagenum].size(); }
+
 QImage Renderer::imageHash(int pagenum) {
-  return loadingHash[pagenum];
+  // while(pagesStillLoading > 0) { qDebug() << "pagesStillLoading!\n";}
+
+  std::optional<QImage> cachedImage = imageCache.get(pagenum);
+
+  if (cachedImage.has_value())
+    return *cachedImage;
+
+  imageCache.push(pagenum, pages[pagenum].render());
+  return *imageCache.get(pagenum);
 }
 
 int Renderer::hashSize() {
-  return loadingHash.keys().length();
+  qDebug() << "pages contains " << pages.size() << " elements.\n";
+  return pages.size();
 }
 
 void Renderer::clearHash() {
   loadingHash.clear();
+  pages.clear();
 }
 
-//Highlighting found text, bookmarks, and page properties disabled for Poppler
+// Highlighting found text, bookmarks, and page properties disabled for Poppler
 bool Renderer::supportsExtraFeatures() { return false; }
 
-void Renderer::traverseOutline(void *, int) { }
+void Renderer::traverseOutline(void *, int) {}
 
 void Renderer::handleLink(QWidget *obj, QString linkDest) {
-  Poppler::Link* trueLink;
-  foreach(QList<Link*> linkArray, linkHash) {
-    for(int i = 0; i < linkArray.size(); i++) {
-      Poppler::Link* link = linkArray[i]->getLink();
-      if(link->linkType() == Poppler::Link::LinkType::Browse) {
-        if(linkDest == dynamic_cast<Poppler::LinkBrowse*>(link)->url())
+  Poppler::Link *trueLink;
+  foreach (QList<LuminaPDF::Link *> linkArray, linkHash) {
+    for (int i = 0; i < linkArray.size(); i++) {
+      Poppler::Link *link = linkArray[i]->getLink();
+      if (link->linkType() == Poppler::Link::LinkType::Browse) {
+        if (linkDest == dynamic_cast<Poppler::LinkBrowse *>(link)->url())
           trueLink = link;
-      }else if(link->linkType() == Poppler::Link::LinkType::Goto) {
-        if(linkDest == dynamic_cast<Poppler::LinkGoto*>(link)->fileName())
+      } else if (link->linkType() == Poppler::Link::LinkType::Goto) {
+        if (linkDest == dynamic_cast<Poppler::LinkGoto *>(link)->fileName())
           trueLink = link;
       }
     }
   }
-  if(trueLink) {
-    if(trueLink->linkType() == Poppler::Link::LinkType::Goto)
-      emit goToPosition(dynamic_cast<Poppler::LinkGoto*>(trueLink)->destination().pageNumber(), 0, 0);
-    else if(trueLink->linkType() == Poppler::Link::LinkType::Browse) {
-      if(QMessageBox::Yes == QMessageBox::question(obj, tr("Open External Link?"), QString(tr("Do you want to open %1 in the default browser")).arg(linkDest), QMessageBox::Yes | QMessageBox::No, QMessageBox::No) ){ QProcess::startDetached("firefox \""+linkDest+"\""); }
+  if (trueLink) {
+    if (trueLink->linkType() == Poppler::Link::LinkType::Goto)
+      emit goToPosition(dynamic_cast<Poppler::LinkGoto *>(trueLink)
+                            ->destination()
+                            .pageNumber(),
+                        0, 0);
+    else if (trueLink->linkType() == Poppler::Link::LinkType::Browse) {
+      if (QMessageBox::Yes ==
+          QMessageBox::question(
+              obj, tr("Open External Link?"),
+              QString(tr("Do you want to open %1 in the default browser"))
+                  .arg(linkDest),
+              QMessageBox::Yes | QMessageBox::No, QMessageBox::No)) {
+        QProcess::startDetached("firefox \"" + linkDest + "\"");
+      }
     }
   }
 }
 
-TextData* Renderer::linkList(int pageNum, int entry) {
-  if(linkHash[pageNum].size() > 0)
+TextData *Renderer::linkList(int pageNum, int entry) {
+  if (linkHash[pageNum].size() > 0)
     return linkHash[pageNum][entry]->getData();
   else
     return 0;
 }
 
-int Renderer::linkSize(int pageNum) { Q_UNUSED(pageNum) return linkHash[pageNum].size(); }
+int Renderer::linkSize(int pageNum) {
+  Q_UNUSED(pageNum) return linkHash[pageNum].size();
+}
 
 int Renderer::annotSize(int pageNum) { Q_UNUSED(pageNum) return 0; }
 
-Annotation *Renderer::annotList(int pageNum, int entry) { Q_UNUSED(pageNum) Q_UNUSED(entry) return NULL; }
+Annotation *Renderer::annotList(int pageNum, int entry) {
+  Q_UNUSED(pageNum) Q_UNUSED(entry) return NULL;
+}
 
 int Renderer::widgetSize(int pageNum) { Q_UNUSED(pageNum) return 0; }
 
-Widget *Renderer::widgetList(int pageNum, int entry) { Q_UNUSED(pageNum) Q_UNUSED(entry) return NULL; }
+Widget *Renderer::widgetList(int pageNum, int entry) {
+  Q_UNUSED(pageNum) Q_UNUSED(entry) return NULL;
+}