From e96dabc467e709a55e67a582da5cbab07ac1ae76 Mon Sep 17 00:00:00 2001
From: Diggory Hardy <diggory.hardy@unibas.ch>
Date: Wed, 13 Aug 2014 18:54:30 +0200
Subject: [PATCH] Fix font size on high-DPI displays in ePub documents (but
 makes images small)

---
 core/generator.h                 | 12 ++++++------
 generators/epub/converter.cpp    |  4 +++-
 generators/epub/epubdocument.cpp |  9 +++++++--
 generators/epub/epubdocument.h   |  2 +-
 4 files changed, 17 insertions(+), 10 deletions(-)

diff --git a/core/generator.h b/core/generator.h
index 9a1d7b26f..e006b9257 100644
--- a/core/generator.h
+++ b/core/generator.h
@@ -430,6 +430,12 @@ class OKULAR_EXPORT Generator : public QObject
          */
         void setDPI(const QSizeF &dpi);
 
+        /**
+         * Returns DPI, previously set via setDPI()
+         * @since 0.19 (KDE 4.13)
+         */
+        QSizeF dpi() const;
+
     Q_SIGNALS:
         /**
          * This signal should be emitted whenever an error occurred in the generator.
@@ -522,12 +528,6 @@ class OKULAR_EXPORT Generator : public QObject
          */
         void updatePageBoundingBox( int page, const NormalizedRect & boundingBox );
 
-        /**
-         * Returns DPI, previously set via setDPI()
-         * @since 0.19 (KDE 4.13)
-         */
-        QSizeF dpi() const;
-
     protected Q_SLOTS:
         /**
          * Gets the font data for the given font
diff --git a/generators/epub/converter.cpp b/generators/epub/converter.cpp
index 392947ea3..ddacfbe44 100644
--- a/generators/epub/converter.cpp
+++ b/generators/epub/converter.cpp
@@ -158,6 +158,7 @@ static QPoint calculateXYPosition( QTextDocument *document, int startPosition )
   double x = startBoundingRect.x() ;
   double y = startBoundingRect.y() + startLine.y();
 
+  //TODO: should this 800 be modified as in 
   y = (int)y % 800;
 
   return QPoint(x,y);
@@ -165,7 +166,8 @@ static QPoint calculateXYPosition( QTextDocument *document, int startPosition )
 
 QTextDocument* Converter::convert( const QString &fileName )
 {
-  EpubDocument *newDocument = new EpubDocument(fileName);
+  EpubDocument *newDocument =
+        new EpubDocument(fileName, generator()->dpi());
   if (!newDocument->isValid()) {
     emit error(i18n("Error while opening the EPub document."), -1);
     delete newDocument;
diff --git a/generators/epub/epubdocument.cpp b/generators/epub/epubdocument.cpp
index 92fafbbfe..5efac7ee7 100644
--- a/generators/epub/epubdocument.cpp
+++ b/generators/epub/epubdocument.cpp
@@ -29,12 +29,17 @@ QString resourceUrl(const KUrl &baseUrl, const QString &u)
 
 }
 
-EpubDocument::EpubDocument(const QString &fileName) : QTextDocument(),
+EpubDocument::EpubDocument(const QString &fileName, QSizeF dpi) :
+    QTextDocument(),
     padding(20)
 {
   mEpub = epub_open(qPrintable(fileName), 3);
 
-  setPageSize(QSizeF(600, 800));
+  //NOTE: the 600, 800 values may or may not be a good base. Scaling by DPI
+  // seems to produce reasonable results.
+  // Assume 96 is the base DPI
+  QSizeF size(600 * dpi.width() / 96.0f, 800 * dpi.height() / 96.0f);
+  setPageSize(size);
 }
 
 bool EpubDocument::isValid()
diff --git a/generators/epub/epubdocument.h b/generators/epub/epubdocument.h
index f0d55b0ea..8cb317b8a 100644
--- a/generators/epub/epubdocument.h
+++ b/generators/epub/epubdocument.h
@@ -22,7 +22,7 @@ namespace Epub {
   class EpubDocument : public QTextDocument {
 
   public:
-    EpubDocument(const QString &fileName);
+    EpubDocument(const QString &fileName, QSizeF dpi);
     bool isValid();
     ~EpubDocument();
     struct epub *getEpub();