Masks as Photoshop's: the button reveals the selection, Alt-click shows a mask alone (13.12)

src/Document/EditorSession+Projects.cpp

@@ -27,7 +27,7 @@ std::optional<ProjectSnapshot> EditorSession::projectSnapshot() const
 void EditorSession::installProject(const ProjectSnapshot &snapshot, const QString &path)
 {
     m_collapsedGroupIDs.clear();
-    m_isMaskSelected = false;
+    setIsMaskSelected(false);
     m_cropRect.reset();
     m_guideDrag = std::nullopt;
     m_transformEdit = std::nullopt;
@@ -78,7 +78,7 @@ void EditorSession::setProjectPath(std::optional<QString> path)
 void EditorSession::clearProject()
 {
     m_collapsedGroupIDs.clear();
-    m_isMaskSelected = false;
+    setIsMaskSelected(false);
     m_cropRect.reset();
     m_transformEdit = std::nullopt;
     m_guideDrag = std::nullopt;

src/Document/EditorSession.cpp

@@ -35,7 +35,7 @@ void EditorSession::setActiveLayerID(std::optional<QUuid> id)
 {
     // Another layer: its pixels are the target again.
     if (id != m_activeLayerID)
-        m_isMaskSelected = false;
+        setIsMaskSelected(false);
     m_activeLayerID = id;
     m_selectedLayerIDs = id ? QSet<QUuid>{*id} : QSet<QUuid>();
     notify();
@@ -234,7 +234,7 @@ void EditorSession::restore(const DocumentHistory::Snapshot &snapshot)
     m_document = snapshot.document;
     setActiveLayerID(snapshot.activeLayerID);
     const std::optional<ImageLayer> active = activeLayer();
-    m_isMaskSelected = keepsMaskTarget && active && active->mask;
+    setIsMaskSelected(keepsMaskTarget && active && active->mask);
     if (changedCanvas && m_document)
         viewport.fit(m_document->size());
     qCInfo(lcApp) << "restored a history snapshot of" << (m_document ? int(m_document->layers.size()) : 0) << "layers";
@@ -381,3 +381,18 @@ void EditorSession::requestCanvasFocus()
     ++m_canvasFocusRequest;
     notify();
 }
+
+void EditorSession::setIsMaskSelected(bool value)
+{
+    m_isMaskSelected = value;
+    if (!value)
+        m_viewsMaskAlone = false;
+}
+
+void EditorSession::setViewsMaskAlone(bool value)
+{
+    if (m_viewsMaskAlone == value)
+        return;
+    m_viewsMaskAlone = value;
+    notify();
+}

src/Document/EditorSession.h

@@ -93,10 +93,11 @@ public:
     void selectTool(NavigationTool value);
     // Tab: the current tool's next mode.
     void cycleToolMode();
-
     // Whether the mask thumbnail, not the layer's, is the target.
     bool isMaskSelected() const { return m_isMaskSelected; }
-
+    // Alt-click: the targeted mask alone, gray, on the canvas.
+    bool viewsMaskAlone() const { return m_viewsMaskAlone; }
+    void setViewsMaskAlone(bool value);
     // A blend mode tried on by hovering; nothing is saved.
     struct BlendPreview {
         QUuid layerID;
@@ -132,7 +133,6 @@ public:
     // An unlinked mask, selected, transforms without its layer.
     bool transformTargetsMask() const;
     void nudgeLayer(double dx, double dy);
-
     const std::optional<LassoDraft> &lassoDraft() const { return m_lassoDraft; }
     LassoKind lassoKind() const { return m_lassoKind; }
     void setLassoKind(LassoKind kind);
@@ -350,6 +350,7 @@ private:
     std::optional<BlendPreview> m_blendPreview;
     std::optional<QUuid> m_opacityEditLayerID;
     bool m_isMaskSelected = false;
+    bool m_viewsMaskAlone = false;
     std::optional<QUuid> m_activeLayerID;
     bool m_isProjectBusy = false;
     bool m_showsNewDocument = false;

src/Document/Filters+Session.cpp

@@ -351,7 +351,7 @@ void EditorSession::finishFilterCommit()
         mask.isEnabled = true;
         mask.placement = std::nullopt;
         m_document->layers[index].mask = mask;
-        m_isMaskSelected = true;
+        setIsMaskSelected(true);
         endEdit();
         finish();
         return;

src/Document/LayerEffects+Session.cpp

@@ -97,7 +97,7 @@ void EditorSession::selectEffect(LayerEffectKind kind, QUuid id, bool editing)
         finishEffectsEditing(false);
     // Swift's `selectedLayerIDs = [id]`: selectLayer sets it, unrefused here.
     selectLayer(id);
-    m_isMaskSelected = false;
+    setIsMaskSelected(false);
     m_effectSelection = selection;
     if (editing && m_effectsEditing != selection) {
         m_effectsEditingOriginal = m_document->layers[size_t(indexOf(m_document->layers, id))].effects.value_or(LayerEffects());

src/Document/LayerMask+Alone.cpp

@@ -0,0 +1,21 @@
+#include "Document/EditorSession.h"
+
+// Swift's mask shown alone, an Alt-click on its thumbnail.
+std::optional<ImageLayer> EditorSession::maskAloneLayer() const
+{
+    const std::optional<ImageLayer> layer = activeLayer();
+    if (!m_viewsMaskAlone || !m_isMaskSelected || !layer || !layer->mask)
+        return std::nullopt;
+    return layer;
+}
+
+void EditorSession::toggleMaskAlone(QUuid id)
+{
+    const std::optional<ImageLayer> shown = maskAloneLayer();
+    const bool showing = shown && shown->id == id;
+    selectLayerTarget(id, true);
+    if (m_activeLayerID != id || !m_isMaskSelected)
+        return;
+    m_viewsMaskAlone = !showing;
+    notify();
+}

src/Document/LayerMask+Session.h

@@ -15,6 +15,12 @@ public:
     std::optional<QImage> maskDistortPreview(const ImageLayer &layer) const;
     // The selection made a mask; without one, a solid mask.
     void addMask(bool revealing = true);
+    // The layer whose mask the canvas shows alone, if any.
+    std::optional<ImageLayer> maskAloneLayer() const;
+    // Alt-click on a mask thumbnail: alone, or the composite again.
+    void toggleMaskAlone(QUuid id);
 
 private:
+    // Swift's didSet: the pixels targeted end the mask view.
+    void setIsMaskSelected(bool value);
     void commitMaskTransform();

src/Document/LayerMask.cpp

@@ -262,7 +262,7 @@ void EditorSession::selectLayerTarget(QUuid id, bool mask)
     resolveGradient();
     selectLayer(id);
     const std::optional<ImageLayer> active = activeLayer();
-    m_isMaskSelected = mask && active && active->mask;
+    setIsMaskSelected(mask && active && active->mask);
     notify();
 }
 
@@ -286,14 +286,15 @@ void EditorSession::addMask(bool revealing)
         // The selection's coverage, soft where it is feathered.
         QImage image = PixelAdjust::coverage(current->clip(m_document->size()), width, height,
                                              BrushRaster::pixelToDocument(active->transform, width, height));
-        if (revealing)
+        // Revealing, white inside; hiding, black inside.
+        if (!revealing)
             image.invertPixels();
         const LayerMask mask(LayerMask::assetFrom(image));
         finishOpacityEdit();
-        beginEdit(QStringLiteral("Add Mask from Selection"));
+        beginEdit(revealing ? QStringLiteral("Reveal Selection") : QStringLiteral("Hide Selection"));
         m_document->layers[size_t(index)].mask = mask;
         m_document->selection = std::nullopt;
-        m_isMaskSelected = true;
+        setIsMaskSelected(true);
         endEdit();
     } catch (const std::runtime_error &error) {
         qCWarning(lcApp).noquote() << "cannot make a mask from the selection:" << error.what();
@@ -312,7 +313,7 @@ void EditorSession::addLayerMask(bool revealing)
         if (layer.id == active->id)
             layer.mask = LayerMask::solid(revealing);
     }
-    m_isMaskSelected = true;
+    setIsMaskSelected(true);
     endEdit();
 }
 
@@ -341,7 +342,7 @@ void EditorSession::deleteLayerMask()
         if (layer.id == active->id)
             layer.mask = std::nullopt;
     }
-    m_isMaskSelected = false;
+    setIsMaskSelected(false);
     endEdit();
 }
 
@@ -371,7 +372,7 @@ void EditorSession::copyMask(QUuid source, QUuid target)
     beginEdit(find(target)->mask ? QStringLiteral("Replace Layer Mask") : QStringLiteral("Copy Layer Mask"));
     find(target)->mask = mask;
     selectLayer(target);
-    m_isMaskSelected = true;
+    setIsMaskSelected(true);
     endEdit();
 }