commit 459bad0f

Poul Sander · 2026-05-17 14:11
459bad0f9d880c4f674925389c33835fce3812c0 patch · browse files
parent 8e0a43bd09d7f5cf579b0f70ac6f38421029795f

Cache folders while switching between them

Changed files

M	src/imagemodel.cpp before
M	src/imagemodel.h before
M	src/mainwindow.cpp before
M	src/mainwindow.h before
M	src/preferencesdialog.cpp before
M	src/preferencesdialog.h before

diff --git a/src/imagemodel.cpp b/src/imagemodel.cpp index 3288ae0..622dbf6 100644 --- a/src/imagemodel.cpp +++ b/src/imagemodel.cpp

@@ -9,7 +9,8 @@

ImageModel::ImageModel(QObject *parent)

: QAbstractListModel(parent)

{

- m_threadPool.setMaxThreadCount(QThread::idealThreadCount());

+ // Limit 1 thread for thumbnail loading to avoid excessive disk I/O on harddrives. SSDs are so fast the extra threads don't help much anyway.

+ m_threadPool.setMaxThreadCount(1); //QThread::idealThreadCount()

m_placeholder = QPixmap(128, 128);

m_placeholder.fill(Qt::lightGray);

@@ -24,12 +25,35 @@ ImageModel::~ImageModel()

m_threadPool.waitForDone();

}

+void ImageModel::setCacheMaxSize(int n)

+ m_cacheMaxSize = std::max(0, n);

+ while (m_cacheOrder.size() > m_cacheMaxSize)

+ m_folderThumbnailCache.remove(m_cacheOrder.takeFirst());

void ImageModel::setDirectory(const QString &path)

{

m_cancelFlag = true;

m_threadPool.waitForDone();

m_cancelFlag = false;

+ // Save current folder's thumbnails to cache before discarding them

+ if (!m_currentDir.isEmpty()) {

+ ThumbnailMap map;

+ for (const Item &item : m_items)

+ if (item.loaded && !item.isFolder)

+ map[item.path] = item.thumbnail;

+ if (!map.isEmpty()) {

+ if (!m_cacheOrder.contains(m_currentDir)) {

+ m_cacheOrder.append(m_currentDir);

+ if (m_cacheOrder.size() > m_cacheMaxSize)

+ m_folderThumbnailCache.remove(m_cacheOrder.takeFirst());

+ }

+ m_folderThumbnailCache[m_currentDir] = std::move(map);

+ }

beginResetModel();

m_items.clear();

m_pendingRows.clear();

@@ -61,9 +85,23 @@ void ImageModel::setDirectory(const QString &path)

const auto files = dir.entryInfoList();

+ // Restore cached thumbnails for this folder if available

+ const ThumbnailMap *cached = m_folderThumbnailCache.contains(path)

+ ? &m_folderThumbnailCache[path]

+ : nullptr;

for (const QFileInfo &file : files)

{

- m_items.append({file.absoluteFilePath(), file.fileName(), m_placeholder, false, false});

+ QPixmap thumb = m_placeholder;

+ bool loaded = false;

+ if (cached) {

+ auto it = cached->find(file.absoluteFilePath());

+ if (it != cached->end()) {

+ thumb = it.value();

+ loaded = true;

+ }

+ m_items.append({file.absoluteFilePath(), file.fileName(), thumb, loaded, false});

}

endResetModel();

diff --git a/src/imagemodel.h b/src/imagemodel.h index 7586159..0be4ed7 100644 --- a/src/imagemodel.h +++ b/src/imagemodel.h

@@ -5,6 +5,8 @@

#include <QVector>

#include <QThreadPool>

#include <QSet>

+#include <QHash>

+#include <QList>

#include <atomic>

#include <QIcon>

@@ -24,6 +26,7 @@ public:

QString currentDirectory() const;

void requestThumbnails(int firstRow, int lastRow);

+ void setCacheMaxSize(int n);

int rowCount(const QModelIndex &parent = QModelIndex()) const override;

QVariant data(const QModelIndex &index, int role) const override;

@@ -42,6 +45,8 @@ private:

void queueRow(int row);

+ using ThumbnailMap = QHash<QString, QPixmap>;

QVector<Item> m_items;

QThreadPool m_threadPool;

QPixmap m_placeholder;

@@ -50,4 +55,9 @@ private:

std::atomic_bool m_cancelFlag{false};

QIcon m_folderIcon;

QString m_currentDir;

+ // Folder thumbnail cache (last N visited directories)

+ QHash<QString, ThumbnailMap> m_folderThumbnailCache;

+ QList<QString> m_cacheOrder;

+ int m_cacheMaxSize = 4;

};

diff --git a/src/mainwindow.cpp b/src/mainwindow.cpp index 312c92f..2086083 100644 --- a/src/mainwindow.cpp +++ b/src/mainwindow.cpp

@@ -439,6 +439,8 @@ void MainWindow::loadPreferences()

m_imageView->setBackgroundColor(m_backgroundColorPreference);

m_lockDockingPreference = settings.value("lockDocking", false).toBool();

applyDockLocking(m_lockDockingPreference);

+ m_folderCacheSizePreference = settings.value("folderCacheSize", 4).toInt();

+ m_imageModel->setCacheMaxSize(m_folderCacheSizePreference);

if (settings.contains("windowGeometry"))

restoreGeometry(settings.value("windowGeometry").toByteArray());

if (settings.contains("windowState"))

@@ -450,6 +452,7 @@ void MainWindow::savePreferences()

QSettings settings("SagoImageBrowser", "SagoImageBrowser");

settings.setValue("backgroundColor", m_backgroundColorPreference);

settings.setValue("lockDocking", m_lockDockingPreference);

+ settings.setValue("folderCacheSize", m_folderCacheSizePreference);

settings.setValue("windowGeometry", saveGeometry());

settings.setValue("windowState", saveState());

}

@@ -459,6 +462,7 @@ void MainWindow::onPreferencesTriggered()

PreferencesDialog dialog(this);

dialog.setBackgroundColor(m_backgroundColorPreference);

dialog.setLockDocking(m_lockDockingPreference);

+ dialog.setCacheSize(m_folderCacheSizePreference);

bool shouldResetLayout = false;

connect(&dialog, &PreferencesDialog::resetLayoutRequested, this, [&shouldResetLayout]() {

@@ -471,6 +475,8 @@ void MainWindow::onPreferencesTriggered()

m_imageView->setBackgroundColor(m_backgroundColorPreference);

m_lockDockingPreference = dialog.getLockDocking();

applyDockLocking(m_lockDockingPreference);

+ m_folderCacheSizePreference = dialog.getCacheSize();

+ m_imageModel->setCacheMaxSize(m_folderCacheSizePreference);

savePreferences();

}

diff --git a/src/mainwindow.h b/src/mainwindow.h index 76bcf9e..39f127d 100644 --- a/src/mainwindow.h +++ b/src/mainwindow.h

@@ -52,6 +52,7 @@ private:

QStackedWidget *m_stack;

QString m_backgroundColorPreference = "black";

+ int m_folderCacheSizePreference = 4;

QWidget *m_browserPage;

ImageViewWidget *m_imageView;

bool m_wasMaximized = false;

diff --git a/src/preferencesdialog.cpp b/src/preferencesdialog.cpp index 32de6c5..a96b863 100644 --- a/src/preferencesdialog.cpp +++ b/src/preferencesdialog.cpp

@@ -4,6 +4,7 @@

#include <QHBoxLayout>

#include <QLabel>

#include <QComboBox>

+#include <QSpinBox>

#include <QCheckBox>

#include <QPushButton>

#include <QGroupBox>

@@ -32,6 +33,17 @@ PreferencesDialog::PreferencesDialog(QWidget *parent)

bgColorLayout->addStretch();

groupLayout->addLayout(bgColorLayout);

+ QHBoxLayout *cacheSizeLayout = new QHBoxLayout;

+ QLabel *cacheSizeLabel = new QLabel("Folder thumbnail cache (folders):");

+ m_cacheSizeSpinBox = new QSpinBox;

+ m_cacheSizeSpinBox->setRange(1, 20);

+ m_cacheSizeSpinBox->setValue(4);

+ cacheSizeLayout->addWidget(cacheSizeLabel);

+ cacheSizeLayout->addWidget(m_cacheSizeSpinBox);

+ cacheSizeLayout->addStretch();

+ groupLayout->addLayout(cacheSizeLayout);

mainLayout->addWidget(imageGroup);

QGroupBox *layoutGroup = new QGroupBox("Layout", this);

@@ -76,6 +88,16 @@ void PreferencesDialog::setBackgroundColor(const QString &color)

m_backgroundColorCombo->setCurrentIndex(index);

}

+int PreferencesDialog::getCacheSize() const

+ return m_cacheSizeSpinBox->value();

+void PreferencesDialog::setCacheSize(int n)

+ m_cacheSizeSpinBox->setValue(n);

bool PreferencesDialog::getLockDocking() const

{

return m_lockDockingCheck->isChecked();

diff --git a/src/preferencesdialog.h b/src/preferencesdialog.h index 391fc8d..a6b79cf 100644 --- a/src/preferencesdialog.h +++ b/src/preferencesdialog.h

@@ -4,6 +4,7 @@

class QComboBox;

class QCheckBox;

+class QSpinBox;

class PreferencesDialog : public QDialog

{

@@ -15,6 +16,9 @@ public:

QString getBackgroundColor() const;

void setBackgroundColor(const QString &color);

+ int getCacheSize() const;

+ void setCacheSize(int n);

bool getLockDocking() const;

void setLockDocking(bool lock);

@@ -26,6 +30,7 @@ signals:

private:

QComboBox *m_backgroundColorCombo;

+ QSpinBox *m_cacheSizeSpinBox;

QCheckBox *m_lockDockingCheck;

QCheckBox *m_resetLayoutCheck;

};