subsurface/core/imagedownloader.h
Berthold Stoeger 23d38a982d Dive pictures: give user option to recalculate thumbnails
Even though hashes of image contents are calculated, the hashes are
not compared to actual file contents in routine-operation. Therefore
give the user the option to recalculate thumbnails, should they have
edited the picture.

Signed-off-by: Berthold Stoeger <bstoeger@mail.tuwien.ac.at>
2018-05-27 23:08:12 +03:00

63 lines
1.7 KiB
C++

// SPDX-License-Identifier: GPL-2.0
#ifndef IMAGEDOWNLOADER_H
#define IMAGEDOWNLOADER_H
#include <QImage>
#include <QFuture>
#include <QNetworkReply>
#include <QThreadPool>
class ImageDownloader : public QObject {
Q_OBJECT
public:
static ImageDownloader *instance();
ImageDownloader();
public slots:
void load(QString filename);
signals:
void loaded(QString filename);
void failed(QString filename);
private:
QNetworkAccessManager manager;
void loadFromUrl(const QString &filename, const QUrl &);
void saveImage(QNetworkReply *reply);
};
struct PictureEntry;
class Thumbnailer : public QObject {
Q_OBJECT
public:
static Thumbnailer *instance();
// Schedule a thumbnail for fetching or calculation.
// Returns a placehlder thumbnail. The actual thumbnail will be sent
// via a signal later.
QImage fetchThumbnail(PictureEntry &entry);
// Schedule multiple thumbnails for forced recalculation
void calculateThumbnails(const QVector<QString> &filenames);
// If we change dive, clear all unfinished thumbnail creations
void clearWorkQueue();
static int maxThumbnailSize();
static int defaultThumbnailSize();
static int thumbnailSize(double zoomLevel);
public slots:
void imageDownloaded(QString filename);
void imageDownloadFailed(QString filename);
signals:
void thumbnailChanged(QString filename, QImage thumbnail);
private:
Thumbnailer();
void recalculate(QString filename);
void processItem(QString filename, bool tryDownload);
mutable QMutex lock;
QThreadPool pool;
QImage failImage; // Shown when image-fetching fails
QImage dummyImage; // Shown before thumbnail is fetched
QMap<QString,QFuture<void>> workingOn;
};
#endif // IMAGEDOWNLOADER_H