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/Rendering/TransformOverlay.h

@@ -0,0 +1,62 @@
+#pragma once
+#include "Document/EditorSession.h"
+#include <QPainter>
+#include <QPalette>
+#include <array>
+#include <optional>
+#include <vector>
+
+// The Move tool's box on screen: handles and a grip.
+struct TransformOverlayGeometry {
+    std::array<QPointF, 8> handles;
+    QPointF rotationHandle;
+    // A distortion has no single rotation: its grip is hidden.
+    bool showsRotation;
+
+    TransformOverlayGeometry(const LayerTransform &transform, const CanvasViewport &viewport, QSizeF documentSize);
+    // A distortion: its corners and the middles of its edges.
+    TransformOverlayGeometry(const Corners &corners, const CanvasViewport &viewport, QSizeF documentSize);
+
+    // What a press takes hold of, within ten points.
+    std::optional<TransformDrag::Mode> hit(QPointF point) const;
+    // The resize cursor along the handle's edge, turned with it.
+    Qt::CursorShape resizeCursor(int index) const;
+    friend bool operator==(const TransformOverlayGeometry &, const TransformOverlayGeometry &) = default;
+};
+
+// Drawn by the canvas over its pixels: Swift's overlay view.
+class TransformOverlay {
+public:
+    explicit TransformOverlay(const EditorSession &session) : m_session(session) {}
+
+    // The marching ants' dash offset, stepped by the canvas.
+    double antsPhase = 0;
+
+    std::optional<TransformOverlayGeometry> geometry() const;
+    // Swift's gradientLine: the pending gradient's ends in view points.
+    std::optional<std::pair<QPointF, QPointF>> gradientLine() const;
+    // Where it draws, so the canvas repaints only that.
+    QRect drawnRect(const QRect &canvas) const;
+    // Where the ants draw: a tick repaints that alone.
+    QRect selectionRect(const QRect &canvas) const;
+    // Swift's crop frame in view points; none off the tool.
+    std::optional<QRectF> cropViewRect() const;
+    // A grip and the view points it takes, corners first.
+    struct CropRegion {
+        int index;
+        QRectF rect;
+    };
+    std::vector<CropRegion> cropResizeRegions() const;
+    void draw(QPainter &context, const QPalette &palette) const;
+
+private:
+    QTransform documentToView() const;
+    void drawTransformHandles(QPainter &context, const QPalette &palette) const;
+    void drawGradientLine(QPainter &context, QPointF start, QPointF end) const;
+    void drawCrop(QPainter &context) const;
+    void drawSelection(QPainter &context) const;
+    void drawLassoDraft(QPainter &context) const;
+    void drawSnapGuides(QPainter &context, const QPalette &palette) const;
+
+    const EditorSession &m_session;
+};