OmaPhoto 1.0.0: the Linux port of Compositor

A layered image editor for Linux and Omarchy, ported from Compositor
(github.com/robbietilton/Compositor), whose Swift source is its
specification. It reads and writes Compositor's .comp projects.

Packages for Ubuntu, Fedora and Arch come from the release workflow;
scripts/install/ holds one install script per distribution family,
and flake.nix serves NixOS.

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

src/UI/NavigationToolHeader.cpp

@@ -0,0 +1,83 @@
+#include "UI/NavigationToolHeader.h"
+#include <QKeyEvent>
+#include <QRegularExpression>
+#include <cmath>
+
+NavigationToolHeader::NavigationToolHeader(EditorSession &session, QWidget *parent)
+    : ToolHeaderBar(QString(), parent), m_session(session), m_zoom(new QLineEdit(this)), m_unit(new QLabel(QStringLiteral("%"), this))
+{
+    m_zoom->setObjectName(QStringLiteral("zoomPercentage"));
+    m_zoom->setAccessibleName(QStringLiteral("Zoom percentage"));
+    m_zoom->setToolTip(QStringLiteral("Zoom percentage (0.1–3200%). Press Return to apply."));
+    m_zoom->setFixedWidth(72);
+    m_zoom->setAlignment(Qt::AlignRight | Qt::AlignVCenter);
+    m_zoom->installEventFilter(this);
+    // The unit sits tight against its field: one value.
+    auto *value = new QHBoxLayout;
+    value->setSpacing(2);
+    value->addWidget(m_zoom);
+    value->addWidget(m_unit);
+    row->insertLayout(1, value);
+    connect(&m_session, &EditorSession::changed, this, &NavigationToolHeader::synchronize);
+    synchronize();
+}
+
+void NavigationToolHeader::synchronize()
+{
+    const bool zooms = m_session.tool() == NavigationTool::zoom;
+    title->setText(zooms ? QStringLiteral("Zoom") : QStringLiteral("Pan"));
+    m_zoom->setVisible(zooms);
+    m_unit->setVisible(zooms);
+    m_zoom->setEnabled(m_session.document().has_value() && !m_session.showsBusy());
+    if (!m_zoom->hasFocus())
+        syncZoom();
+}
+
+void NavigationToolHeader::syncZoom()
+{
+    static const QRegularExpression trailingZeros(QStringLiteral("\\.?0+$"));
+    m_displayed = QString::number(m_session.viewport.zoom() * 100, 'f', 2).remove(trailingZeros);
+    m_zoom->setText(m_displayed);
+}
+
+void NavigationToolHeader::applyZoom()
+{
+    if (m_zoom->text() != m_displayed) {
+        // No number reads as zero; "inf" the viewport refuses.
+        const double value = m_zoom->text().trimmed().remove(QLatin1Char('%')).toDouble();
+        if (value > 0 && !m_session.isProjectBusy())
+            m_session.zoom(value / 100);
+    }
+    syncZoom();
+}
+
+void NavigationToolHeader::step(double percent)
+{
+    m_zoom->setText(QString::number(std::clamp(percent, 0.1, 3200.0), 'g', 6));
+    applyZoom();
+}
+
+bool NavigationToolHeader::eventFilter(QObject *watched, QEvent *event)
+{
+    if (event->type() == QEvent::FocusOut)
+        applyZoom();
+    if (event->type() != QEvent::KeyPress)
+        return ToolHeaderBar::eventFilter(watched, event);
+    const auto *key = static_cast<QKeyEvent *>(event);
+    // Return and Escape apply, then hand the canvas the keys.
+    if (key->key() == Qt::Key_Return || key->key() == Qt::Key_Enter || key->key() == Qt::Key_Escape) {
+        applyZoom();
+        m_zoom->clearFocus();
+        m_session.requestCanvasFocus();
+        return true;
+    }
+    if (key->key() != Qt::Key_Up && key->key() != Qt::Key_Down)
+        return ToolHeaderBar::eventFilter(watched, event);
+    // Up and Down step one percent, ten with Shift.
+    static const QRegularExpression notNumeric(QStringLiteral("[^0-9.]"));
+    bool isNumber = false;
+    const double typed = m_zoom->text().remove(notNumeric).toDouble(&isNumber);
+    const double amount = (key->modifiers() & Qt::ShiftModifier ? 10 : 1) * (key->key() == Qt::Key_Up ? 1 : -1);
+    step((isNumber ? typed : m_session.viewport.zoom() * 100) + amount);
+    return true;
+}