Get lumina-pdf working with the poppler backend once again.

Also have it dynamically keep up to 5 pages in the cache at once. Load on demand as page number changes instead.
Still have some debugging enabled for further testing.

7 files changed, 92 insertions, 53 deletions

diff --git a/src-qt5/desktop-utils/lumina-pdf/PrintWidget.cpp b/src-qt5/desktop-utils/lumina-pdf/PrintWidget.cpp
index 7a2251cd..53f3fa62 100644
--- a/src-qt5/desktop-utils/lumina-pdf/PrintWidget.cpp
+++ b/src-qt5/desktop-utils/lumina-pdf/PrintWidget.cpp
@@ -1,6 +1,7 @@
 #include "PrintWidget.h"
 #include <QGraphicsProxyWidget>
 #include <QPushButton>
+#include <QtConcurrent>
 
 PrintWidget::PrintWidget(Renderer *backend, QWidget *parent)
     : QGraphicsView(parent), scene(0), curPage(1), viewMode(SinglePageView),
@@ -129,11 +130,23 @@ void PrintWidget::setCurrentPage(int pageNumber) {
       this->centerOn(pages.at(curPage - 1));
     }
   }*/
-
-  if (lastPage != curPage){
+  QSize DPI(300, 300);
+  if (lastPage != curPage || !BACKEND->imageSize(curPage).isNull()){
     updatePreview();
+    for(int i=(curPage-3); i<BACKEND->numPages(); i++){
+      if(i<0){ continue; }
+      else if( i < (curPage-2) ){ BACKEND->clearHash(i); }
+      else if( i > (curPage+2) ){ BACKEND->clearHash(i); }
+      else{
+         if (BACKEND->loadMultiThread()) {
+          QtConcurrent::run(BACKEND, &Renderer::renderPage, i, DPI, degrees);
+        } else {
+          BACKEND->renderPage(i, DPI, degrees);
+        }
+      }
+    }
   }
-  //qDebug() << "Current page set to " << pageNumber << "\n";
+  qDebug() << "Current page set to " << pageNumber << "\n";
 }
 
 void PrintWidget::highlightText(TextData *text) {
diff --git a/src-qt5/desktop-utils/lumina-pdf/PrintWidget.h b/src-qt5/desktop-utils/lumina-pdf/PrintWidget.h
index 1240d140..0eebeb88 100644
--- a/src-qt5/desktop-utils/lumina-pdf/PrintWidget.h
+++ b/src-qt5/desktop-utils/lumina-pdf/PrintWidget.h
@@ -60,7 +60,7 @@ public:
   ZoomMode getZoomMode() const { return this->zoomMode; }
   int currentPage() const {
     return curPage;
-    return publicPageNum;
+    //return publicPageNum;
   }
 
 signals:
diff --git a/src-qt5/desktop-utils/lumina-pdf/Renderer-mupdf.cpp b/src-qt5/desktop-utils/lumina-pdf/Renderer-mupdf.cpp
index 002650f2..5acf71c7 100644
--- a/src-qt5/desktop-utils/lumina-pdf/Renderer-mupdf.cpp
+++ b/src-qt5/desktop-utils/lumina-pdf/Renderer-mupdf.cpp
@@ -657,9 +657,10 @@ QSize Renderer::imageSize(int pagenum){
 
 int Renderer::hashSize() { return dataHash.size(); }
 
-void Renderer::clearHash() {
+void Renderer::clearHash(int pagenum) {
   //qDeleteAll(dataHash);
-  dataHash.clear();
+  if(pagenum<0){ dataHash.clear(); }
+  else if(dataHash.contains(pagenum)){ dataHash.remove(pagenum); }
 }
 
 TextData *Renderer::linkList(int pagenum, int entry) {
diff --git a/src-qt5/desktop-utils/lumina-pdf/Renderer-poppler.cpp b/src-qt5/desktop-utils/lumina-pdf/Renderer-poppler.cpp
index 8f0755d4..a1620e92 100644
--- a/src-qt5/desktop-utils/lumina-pdf/Renderer-poppler.cpp
+++ b/src-qt5/desktop-utils/lumina-pdf/Renderer-poppler.cpp
@@ -1,7 +1,7 @@
 #include "Renderer.h"
 #include "drawablepage.h"
 #include "link.h"
-#include "lrucache.h"
+//#include "lrucache.h"
 #include <QThread>
 #include <atomic>
 #include <poppler/qt5/poppler-qt5.h>
@@ -9,21 +9,24 @@
 static std::unique_ptr<Poppler::Document> DOC;
 QHash<int, QImage> loadingHash;
 
-static std::vector<LuminaPDF::drawablePage> pages;
+//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;
+//static LuminaPDF::LRUCache<QImage> imageCache;
+
+QSize DPI;
+int ROTATE = 0;
 
 Renderer::Renderer() : pnum(0), needpass(false), degrees(0) {
   DOC.reset(nullptr);
   pagesStillLoading = 1;
-  imageCache.setCacheSize(5);
+  //imageCache.setCacheSize(5);
 }
 
 Renderer::~Renderer() {
   // qDeleteAll(loadingHash);
-  pages.clear();
+  //pages.clear();
   for (auto &linkList : links) {
     qDeleteAll(linkList);
   }
@@ -41,7 +44,7 @@ bool Renderer::loadDocument(QString path, QString password) {
   if (DOC != nullptr && path != docpath) {
     // Clear out the old document first
     DOC.reset(nullptr);
-    pages.clear();
+    //pages.clear();
     links.clear();
     needpass = false;
     pnum = 0;
@@ -83,9 +86,9 @@ bool Renderer::loadDocument(QString path, QString password) {
         WIDGET->setOrientation(QPageLayout::Portrait);
     }*/
     delete PAGE;
-    pages.reserve(pnum + 1);
+    //pages.reserve(pnum + 1);
 
-    for (int i = 0; i < pnum + 1; ++i) {
+    /*for (int i = 0; i < pnum + 1; ++i) {
       LuminaPDF::drawablePage temp;
       pages.emplace_back(std::move(temp));
     }
@@ -94,8 +97,8 @@ bool Renderer::loadDocument(QString path, QString password) {
       QList<LuminaPDF::Link *> temp;
       links.push_back(temp);
     }
-
-    pagesStillLoading = pnum;
+    */
+    //pagesStillLoading = pnum;
 
     return true; // could load the first page
   }
@@ -103,9 +106,9 @@ bool Renderer::loadDocument(QString path, QString password) {
 }
 
 void Renderer::renderPage(int pagenum, QSize DPI, int degrees) {
-  // qDebug() << "Render Page:" << pagenum << DPI << degrees;
-
-  emit SetProgress(pages.size() - pagesStillLoading);
+  if(loadingHash.contains(pagenum)){ return; } //nothing to do
+ qDebug() << "Render Page:" << pagenum << DPI << degrees;
+  //emit SetProgress(pnum - pagesStillLoading);
 
   if (DOC != nullptr) {
     Poppler::Page *PAGE = DOC->page(pagenum - 1);
@@ -127,11 +130,11 @@ void Renderer::renderPage(int pagenum, QSize DPI, int degrees) {
       }
 
       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;
+      //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;
@@ -146,21 +149,22 @@ void Renderer::renderPage(int pagenum, QSize DPI, int degrees) {
 
       links[pagenum] = linkArray;
       // linkHash.insert(pagenum, linkArray);
+      */
     }
-    // qDebug() << "Done Render Page:" << pagenum << img.size();
+    //qDebug() << "Done Render Page:" << pagenum << img.size();
   } else {
-    pages[pagenum] = LuminaPDF::drawablePage();
-    // loadingHash.insert(pagenum, QImage());
+    //pages[pagenum] = LuminaPDF::drawablePage();
+    loadingHash.insert(pagenum, QImage());
   }
 
-  if (pagesStillLoading == 1) {
+  //if (pagesStillLoading > 0) {
     emit PageLoaded(pagenum);
-  }
+  //}
 
-  --pagesStillLoading;
+  //--pagesStillLoading;
 }
 
-bool Renderer::isDoneLoading(int page) { return imageCache.contains(page); }
+bool Renderer::isDoneLoading(int page) { return loadingHash.contains(page); }
 
 QList<TextData *> Renderer::searchDocument(QString text, bool matchCase) {
   QList<TextData *> results;
@@ -178,31 +182,37 @@ QList<TextData *> Renderer::searchDocument(QString text, bool matchCase) {
 }
 
 QSize Renderer::imageSize(int pagenum) {
-  if(!imageCache.contains(pagenum)){ return QSize(); }
-  return pages[pagenum].size();
+  if(!loadingHash.contains(pagenum)){ return QSize(); }
+  return loadingHash[pagenum].size();
 }
 
 QImage Renderer::imageHash(int pagenum) {
-  if(!imageCache.contains(pagenum)){ return QImage(); }
+  if(loadingHash.contains(pagenum)){
+    return loadingHash[pagenum];
+  }else{
+    return QImage();
+  }
+  //if(!imageCache.contains(pagenum)){ return QImage(); }
   // while(pagesStillLoading > 0) { qDebug() << "pagesStillLoading!\n";}
 
-  std::optional<QImage> cachedImage = imageCache.get(pagenum);
+  //std::optional<QImage> cachedImage = imageCache.get(pagenum);
 
-  if (cachedImage.has_value())
-    return *cachedImage;
+  /*if (cachedImage.has_value())
+    return *cachedImage;*/
 
-  imageCache.push(pagenum, pages[pagenum].render());
-  return *imageCache.get(pagenum);
+  //imageCache.push(pagenum, pages[pagenum].render());
+  //return *imageCache.get(pagenum);
 }
 
 int Renderer::hashSize() {
-  qDebug() << "pages contains " << pages.size() << " elements.\n";
-  return pages.size();
+  //qDebug() << "pages contains " << pages.size() << " elements.\n";
+  return loadingHash.size();
 }
 
-void Renderer::clearHash() {
-  loadingHash.clear();
-  pages.clear();
+void Renderer::clearHash( int pagenum) {
+  if(pagenum<0){ loadingHash.clear(); }
+  else if(loadingHash.contains(pagenum)){ loadingHash.remove(pagenum); }
+  //pages.clear();
 }
 
 // Highlighting found text, bookmarks, and page properties disabled for Poppler
diff --git a/src-qt5/desktop-utils/lumina-pdf/Renderer.h b/src-qt5/desktop-utils/lumina-pdf/Renderer.h
index 6d4e4736..3b3fa3c7 100644
--- a/src-qt5/desktop-utils/lumina-pdf/Renderer.h
+++ b/src-qt5/desktop-utils/lumina-pdf/Renderer.h
@@ -59,7 +59,7 @@ public:
   virtual Widget *widgetList(int, int);
   virtual int widgetSize(int);
 
-  virtual void clearHash();
+  virtual void clearHash(int pagenum = -1);
   // Makes sure degrees is between 0 and 360 then rotates the matrix and
   void setDegrees(int degrees) {
     // Mods by 360, but adds and remods because of how C++ treats negative mods
diff --git a/src-qt5/desktop-utils/lumina-pdf/lrucache.h b/src-qt5/desktop-utils/lumina-pdf/lrucache.h
index 8c68c1bb..0ed241c2 100644
--- a/src-qt5/desktop-utils/lumina-pdf/lrucache.h
+++ b/src-qt5/desktop-utils/lumina-pdf/lrucache.h
@@ -44,6 +44,11 @@ public:
     hashmap[k] = values.begin();
   }
 
+  bool contains(const Key k){
+    auto itr = hashmap.find(k);
+    return ( itr!=hashmap.end() );
+  }
+
 private:
   size_t max;
   std::list<std::tuple<Key, Value>> values;
diff --git a/src-qt5/desktop-utils/lumina-pdf/mainUI.cpp b/src-qt5/desktop-utils/lumina-pdf/mainUI.cpp
index 1b93f3c3..8278f77a 100644
--- a/src-qt5/desktop-utils/lumina-pdf/mainUI.cpp
+++ b/src-qt5/desktop-utils/lumina-pdf/mainUI.cpp
@@ -481,7 +481,13 @@ void MainUI::startLoadingPages(int degrees) {
   // pixelization) The best approach seams to be to increase the DPI a bit, but
   // match that with the same scaling on the page size (smoothing)
 
-  QSize DPI(250, 250); // print-quality (some printers even go to 600 DPI nowdays)
+  //QSize DPI(250, 250); // print-quality (some printers even go to 600 DPI nowdays)
+
+
+  int curpage = WIDGET->currentPage();
+  if(curpage<0){ curpage = 1; }
+  else if(curpage>=BACKEND->numPages()){ curpage=BACKEND->numPages(); }
+  WIDGET->setCurrentPage(curpage);
 
   /*qDebug() << "Screen Resolutions:";
   QList<QScreen*> screens = QApplication::screens();
@@ -489,7 +495,7 @@ void MainUI::startLoadingPages(int degrees) {
     qDebug() << screens[i]->name() << screens[i]->logicalDotsPerInchX() <<
   screens[i]->logicalDotsPerInchY();
   }*/
-  int n = BACKEND->numPages() + 1;
+  /*int n = BACKEND->numPages() + 1;
   for (int i = 1; i < n; i++) {
     // qDebug() << " - Kickoff page load:" << i;
     if (BACKEND->loadMultiThread()) {
@@ -500,23 +506,27 @@ void MainUI::startLoadingPages(int degrees) {
         QCoreApplication::processEvents();
       }
     }
-  }
+  }*/
   //qDebug() << "Finish page loading kickoff";
 }
 
 void MainUI::slotSetProgress(int finished) { progress->setValue(finished); }
 
 void MainUI::slotPageLoaded(int page) {
+  int curpage = WIDGET->currentPage();
+  if(curpage == page || (curpage <0 && page==1) ){
+    //current page loaded
+
   //qDebug() << "slotPageLoaded";
-  loadingQueue.push_back(page);
-  int finished = loadingQueue.size();
+  /*loadingQueue.push_back(page);
+  int finished = loadingQueue.size();*/
   //qDebug() << "Page Loaded:" << page << finished;
-  if (finished == BACKEND->numPages()) {
+  //if (finished == BACKEND->numPages()) {
     progAct->setVisible(false);
     WIDGET->setVisible(true);
     BOOKMARKS->setVisible(true);
-    ui->splitter->setSizes(QList<int>() << 0 << this->width());
-    WIDGET->setCurrentPage(1);
+    //ui->splitter->setSizes(QList<int>() << 0 << this->width());
+    //WIDGET->setCurrentPage(1);
     ui->actionStop_Presentation->setEnabled(false);
     ui->actionStart_Here->setEnabled(true);
     ui->actionStart_Begin->setEnabled(true);