viewer: ROI panel refinements — persist edits, combobox, compact toggles

- Edited ROIs now override the file's for every subsequently loaded image
  and survive settings changes, until a new file is opened (previously a
  delete/add was lost on the next image). Tracked via an roi_override_ that
  is re-applied to curr_experiment and to each loaded image's dataset.
- The ROI selector is a compact combobox instead of a list widget.
- "Show labels" and "Translucent fill" share one row to save space.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

viewer/JFJochImageReadingWorker.cpp

@@ -271,6 +271,7 @@ void JFJochImageReadingWorker::LoadFile_i(const QString &filename, qint64 image_
         current_file = filename;
         if (dataset) {
             curr_experiment = dataset->experiment;
+            roi_override_.reset();   // new file: use its ROIs, forget any earlier edits
             curr_experiment.ImportIndexingSettings(indexing_settings);
             curr_experiment.ImportAzimuthalIntegrationSettings(azint_settings);
             UpdateAzint_i(dataset.get());
@@ -378,6 +379,8 @@ void JFJochImageReadingWorker::LoadImage_i(int64_t image_number, int64_t summati
             return;
         }
 
+        ApplyROIOverrideToImage_i();   // edited ROIs win over the file's for every image
+
         current_image = current_image_ptr->ImageData().number;
         current_summation = summation;
 
@@ -466,6 +469,8 @@ void JFJochImageReadingWorker::UpdateDataset_i(const std::optional<DiffractionEx
     }
 
     curr_experiment = dataset->experiment;
+    if (roi_override_)
+        curr_experiment.ROI().SetROI(*roi_override_);   // keep edited ROIs across settings changes
     curr_experiment.ImportIndexingSettings(indexing_settings);
     curr_experiment.ImportAzimuthalIntegrationSettings(azint_settings);
     UpdateAzint_i(dataset.get());
@@ -473,6 +478,7 @@ void JFJochImageReadingWorker::UpdateDataset_i(const std::optional<DiffractionEx
     emit datasetLoaded(dataset);
 
     current_image_ptr = std::make_shared<JFJochReaderImage>(current_image_ptr->ImageData(), dataset);
+    ApplyROIOverrideToImage_i();
 
     if (auto_reanalyze)
         ReanalyzeImage_i();
@@ -596,7 +602,9 @@ void JFJochImageReadingWorker::SetROIDefinition(const ROIDefinition &rois) {
 
 void JFJochImageReadingWorker::SetROIDefinition_i(const ROIDefinition &rois) {
     // The worker experiment is the source of truth; the analysis ROI engine is rebuilt
-    // for it so newly loaded images pick up the change automatically.
+    // for it so newly loaded images pick up the change automatically. From now on the
+    // edited ROIs override whatever the file carried.
+    roi_override_ = rois;
     curr_experiment.ROI().SetROI(rois);
     if (image_analysis)
         image_analysis->RebuildROI();
@@ -623,6 +631,15 @@ void JFJochImageReadingWorker::SetROIDefinition_i(const ROIDefinition &rois) {
     emit imageLoaded(current_image_ptr);
 }
 
+void JFJochImageReadingWorker::ApplyROIOverrideToImage_i() {
+    if (!roi_override_ || !current_image_ptr)
+        return;
+    auto md = current_image_ptr->CreateMutableDataset();
+    md->experiment.ROI().SetROI(*roi_override_);
+    current_image_ptr = std::make_shared<JFJochReaderImage>(
+        current_image_ptr->ImageData(), std::shared_ptr<const JFJochReaderDataset>(md));
+}
+
 void JFJochImageReadingWorker::UpdateUserMask_i(const std::vector<uint32_t> &mask) {
     std::shared_ptr<const JFJochReaderDataset> dataset;
     if (http_mode) {

viewer/JFJochImageReadingWorker.h

@@ -53,6 +53,9 @@ private:
     QString current_file;
 
     DiffractionExperiment curr_experiment;
+    // Once the user edits ROIs they override whatever the file carried, for this and
+    // every subsequently loaded image, until a new file is opened.
+    std::optional<ROIDefinition> roi_override_;
     IndexingSettings indexing_settings;
     AzimuthalIntegrationSettings azint_settings;
     std::unique_ptr<IndexerThreadPool> indexing;
@@ -119,6 +122,7 @@ private:
     void UpdateAzint_i(const JFJochReaderDataset *dataset);
     void UpdateUserMask_i(const std::vector<uint32_t> &mask);
     void SetROIDefinition_i(const ROIDefinition &rois);
+    void ApplyROIOverrideToImage_i();   // rewrite current_image_ptr's dataset with roi_override_
     void setAutoLoadMode_i(AutoloadMode mode);
 
 signals:

viewer/JFJochViewerSidePanel.cpp

@@ -113,15 +113,18 @@ JFJochViewerSidePanel::JFJochViewerSidePanel(QWidget *parent) : QWidget(parent)
 
     layout->addWidget(new TitleLabel("ROI", this));
 
-    auto roiLabelsCheckBox = new QCheckBox("Show ROI labels", this);
+    auto roiLabelsCheckBox = new QCheckBox("Show labels", this);
     roiLabelsCheckBox->setCheckState(Qt::CheckState::Unchecked);
     connect(roiLabelsCheckBox, &QCheckBox::toggled, this, &JFJochViewerSidePanel::showROILabels);
-    layout->addWidget(roiLabelsCheckBox);
 
-    auto roiFillCheckBox = new QCheckBox("Translucent ROI fill", this);
+    auto roiFillCheckBox = new QCheckBox("Translucent fill", this);
     roiFillCheckBox->setCheckState(Qt::CheckState::Unchecked);
     connect(roiFillCheckBox, &QCheckBox::toggled, this, &JFJochViewerSidePanel::showROIFill);
-    layout->addWidget(roiFillCheckBox);
+
+    auto roiToggleRow = new QHBoxLayout();
+    roiToggleRow->addWidget(roiLabelsCheckBox);
+    roiToggleRow->addWidget(roiFillCheckBox);
+    layout->addLayout(roiToggleRow);
 
     roi_list = new JFJochViewerROIList(this);
     layout->addWidget(roi_list);

viewer/widgets/JFJochViewerROIList.cpp

@@ -9,15 +9,13 @@
 #include <QHBoxLayout>
 #include <QPushButton>
 #include <QInputDialog>
-#include <QListWidgetItem>
 
 JFJochViewerROIList::JFJochViewerROIList(QWidget *parent) : QWidget(parent) {
     auto *layout = new QVBoxLayout(this);
 
-    list_ = new QListWidget(this);
-    list_->setMaximumHeight(120);
-    layout->addWidget(list_);
-    connect(list_, &QListWidget::itemSelectionChanged, this, &JFJochViewerROIList::OnSelectionChanged);
+    combo_ = new QComboBox(this);
+    layout->addWidget(combo_);
+    connect(combo_, &QComboBox::currentIndexChanged, this, &JFJochViewerROIList::OnSelectionChanged);
 
     auto *buttons = new QHBoxLayout();
     type_combo_ = new QComboBox(this);
@@ -42,36 +40,33 @@ void JFJochViewerROIList::loadImage(std::shared_ptr<const JFJochReaderImage> ima
     image_ = image;
     const QString keep = SelectedName();
     rois_ = image_ ? image_->Dataset().experiment.ROI().GetROIDefinition() : ROIDefinition{};
-    RebuildList(keep);
+    RebuildCombo(keep);
     ShowSelectedResult();
 }
 
-void JFJochViewerROIList::RebuildList(const QString &keep_selected) {
+void JFJochViewerROIList::RebuildCombo(const QString &keep_selected) {
     rebuilding_ = true;
-    list_->clear();
+    combo_->clear();
 
     auto add_item = [&](const std::string &name, const char *type) {
-        auto *item = new QListWidgetItem(QString("%1  ·  %2").arg(QString::fromStdString(name), type));
-        item->setData(Qt::UserRole, QString::fromStdString(name));   // name independent of display text
-        list_->addItem(item);
+        // display "name · type", with the bare name kept as item data for lookups
+        combo_->addItem(QString("%1  ·  %2").arg(QString::fromStdString(name), type),
+                        QString::fromStdString(name));
     };
     for (const auto &b : rois_.boxes) add_item(b.GetName(), "box");
     for (const auto &c : rois_.circles) add_item(c.GetName(), "circle");
     for (const auto &a : rois_.azimuthal) add_item(a.GetName(), "azim");
 
     if (!keep_selected.isEmpty()) {
-        for (int i = 0; i < list_->count(); i++)
-            if (list_->item(i)->data(Qt::UserRole).toString() == keep_selected) {
-                list_->setCurrentRow(i);
-                break;
-            }
+        const int idx = combo_->findData(keep_selected);
+        if (idx >= 0)
+            combo_->setCurrentIndex(idx);
     }
     rebuilding_ = false;
 }
 
 QString JFJochViewerROIList::SelectedName() const {
-    auto *item = list_->currentItem();
-    return item ? item->data(Qt::UserRole).toString() : QString();
+    return combo_->currentData().toString();
 }
 
 void JFJochViewerROIList::ShowSelectedResult() {
@@ -121,7 +116,7 @@ void JFJochViewerROIList::OnAdd() {
         default: rois_.azimuthal.emplace_back(name, 2.0f, 4.0f); break;
     }
     emit roisChanged(rois_);
-    RebuildList(QString::fromStdString(name));
+    RebuildCombo(QString::fromStdString(name));
     ShowSelectedResult();
 }
 
@@ -137,7 +132,7 @@ void JFJochViewerROIList::OnDelete() {
     };
     if (erase_by_name(rois_.boxes) || erase_by_name(rois_.circles) || erase_by_name(rois_.azimuthal)) {
         emit roisChanged(rois_);
-        RebuildList(QString());
+        RebuildCombo(QString());
         ShowSelectedResult();
     }
 }
@@ -168,6 +163,6 @@ void JFJochViewerROIList::OnRename() {
         }
 
     emit roisChanged(rois_);
-    RebuildList(new_name);
+    RebuildCombo(new_name);
     ShowSelectedResult();
 }

viewer/widgets/JFJochViewerROIList.h

@@ -6,7 +6,6 @@
 #include <memory>
 
 #include <QWidget>
-#include <QListWidget>
 #include <QComboBox>
 
 #include "JFJochViewerROIResult.h"
@@ -20,7 +19,7 @@
 class JFJochViewerROIList : public QWidget {
     Q_OBJECT
 
-    QListWidget *list_;
+    QComboBox *combo_;
     QComboBox *type_combo_;
     JFJochViewerROIResult *result_;
 
@@ -28,7 +27,7 @@ class JFJochViewerROIList : public QWidget {
     std::shared_ptr<const JFJochReaderImage> image_;
     bool rebuilding_ = false;
 
-    void RebuildList(const QString &keep_selected);
+    void RebuildCombo(const QString &keep_selected);
     void ShowSelectedResult();
     [[nodiscard]] QString SelectedName() const;
     [[nodiscard]] std::string UniqueName() const;