looqs/gui/pdfworker.cpp

101 rivejä
2.3 KiB
C++

#include <QApplication>
#include <QScreen>
#include <QDebug>
#include <QScopedPointer>
#include <QMutexLocker>
#include <QtConcurrent/QtConcurrent>
#include <QtConcurrent/QtConcurrentMap>
#include "pdfworker.h"
static QMutex cacheMutex;
struct Renderer
{
typedef PdfPreview result_type;
double scaleX;
double scaleY;
QHash<QString, Poppler::Document *> documentcache;
Renderer(double scaleX, double scaleY)
{
this->scaleX = scaleX;
this->scaleY = scaleY;
}
~Renderer()
{
qDeleteAll(documentcache);
}
Poppler::Document *document(QString path)
{
if(documentcache.contains(path))
return documentcache.value(path);
Poppler::Document *result = Poppler::Document::load(path);
if(result == nullptr)
{
//TODO: some kind of user feedback would be nicec
return nullptr;
}
result->setRenderHint(Poppler::Document::TextAntialiasing);
QMutexLocker locker(&cacheMutex);
documentcache.insert(path, result);
return result;
}
PdfPreview operator()(const PdfPreview &preview)
{
Poppler::Document *doc = document(preview.documentPath);
if(doc == nullptr)
{
return preview;
}
if(doc->isLocked())
{
return preview;
}
int p = (int)preview.page - 1;
if(p < 0)
{
p = 0;
}
Poppler::Page *pdfPage = doc->page(p);
PdfPreview result = preview;
result.previewImage = pdfPage->renderToImage(scaleX, scaleY);
return result;
}
};
QFuture<PdfPreview> PdfWorker::generatePreviews(const QVector<SearchResult> paths, double scalefactor)
{
QVector<PdfPreview> previews;
for(const SearchResult &sr : paths)
{
for(int page : sr.pages)
{
PdfPreview p;
p.documentPath = sr.fileData.absPath;
p.page = page;
previews.append(p);
}
}
double scaleX = QGuiApplication::primaryScreen()->physicalDotsPerInchX() * scalefactor;
double scaleY = QGuiApplication::primaryScreen()->physicalDotsPerInchY() * scalefactor;
return QtConcurrent::mapped(previews, Renderer(scaleX, scaleY));
}