Port window cascading from X11 desktop ids to VirtualDesktop

src/placement.cpp

@@ -31,7 +31,7 @@ namespace KWin
 
 Placement::Placement()
 {
-    reinitCascading(0);
+    reinitCascading();
 }
 
 /**
@@ -335,24 +335,24 @@ void Placement::placeSmart(Window *window, const QRectF &area, PlacementPolicy /
     window->move(QPoint(x_optimal, y_optimal));
 }
 
-void Placement::reinitCascading(int desktop)
+void Placement::reinitCascading()
 {
-    // desktop == 0 - reinit all
-    if (desktop == 0) {
-        cci.clear();
-        for (uint i = 0; i < VirtualDesktopManager::self()->count(); ++i) {
-            DesktopCascadingInfo inf;
-            inf.pos = QPoint(-1, -1);
-            inf.col = 0;
-            inf.row = 0;
-            cci.append(inf);
-        }
-    } else {
-        cci[desktop - 1].pos = QPoint(-1, -1);
-        cci[desktop - 1].col = cci[desktop - 1].row = 0;
+    cci.clear();
+    const auto desktops = VirtualDesktopManager::self()->desktops();
+    for (VirtualDesktop *desktop : desktops) {
+        reinitCascading(desktop);
     }
 }
 
+void Placement::reinitCascading(VirtualDesktop *desktop)
+{
+    cci[desktop] = DesktopCascadingInfo{
+        .pos = QPoint(-1, -1),
+        .col = 0,
+        .row = 0,
+    };
+}
+
 QPoint Workspace::cascadeOffset(const Window *c) const
 {
     QRect area = clientArea(PlacementArea, c, c->frameGeometry().center()).toRect();
@@ -373,7 +373,7 @@ void Placement::placeCascaded(Window *c, const QRect &area, PlacementPolicy next
     // CT how do I get from the 'Client' class the size that NW squarish "handle"
     const QPoint delta = workspace()->cascadeOffset(c);
 
-    const int dn = c->desktop() == 0 || c->isOnAllDesktops() ? (VirtualDesktopManager::self()->current() - 1) : (c->desktop() - 1);
+    VirtualDesktop *dn = c->isOnCurrentDesktop() ? VirtualDesktopManager::self()->currentDesktop() : c->desktops().constLast();
 
     if (nextPlacement == PlacementUnknown) {
         nextPlacement = PlacementSmart;
@@ -630,8 +630,7 @@ void Placement::cascadeIfCovering(Window *window, const QRectF &area)
 void Placement::cascadeDesktop()
 {
     Workspace *ws = Workspace::self();
-    const int desktop = VirtualDesktopManager::self()->current();
-    reinitCascading(desktop);
+    reinitCascading(VirtualDesktopManager::self()->currentDesktop());
     const auto stackingOrder = ws->stackingOrder();
     for (Window *window : stackingOrder) {
         if (!window->isClient() || (!window->isOnCurrentDesktop()) || (window->isMinimized()) || (window->isOnAllDesktops()) || (!window->isMovable())) {

src/placement.h

@@ -22,6 +22,7 @@ class QObject;
 namespace KWin
 {
 
+class VirtualDesktop;
 class Window;
 
 class KWIN_EXPORT Placement
@@ -34,7 +35,8 @@ public:
 
     void placeCentered(Window *c, const QRectF &area, PlacementPolicy next = PlacementUnknown);
 
-    void reinitCascading(int desktop);
+    void reinitCascading();
+    void reinitCascading(VirtualDesktop *desktop);
 
     void cascadeIfCovering(Window *c, const QRectF &area);
 
@@ -71,7 +73,7 @@ private:
         int row;
     };
 
-    QList<DesktopCascadingInfo> cci;
+    QHash<VirtualDesktop *, DesktopCascadingInfo> cci;
 };
 
 } // namespace

src/workspace.cpp

@@ -1384,7 +1384,7 @@ void Workspace::updateOutputs(const QVector<Output *> &outputOrder)
 void Workspace::slotDesktopAdded(VirtualDesktop *desktop)
 {
     m_focusChain->addDesktop(desktop);
-    m_placement->reinitCascading(0);
+    m_placement->reinitCascading();
     updateClientArea();
 }
 
@@ -1409,7 +1409,7 @@ void Workspace::slotDesktopRemoved(VirtualDesktop *desktop)
     }
 
     updateClientArea();
-    m_placement->reinitCascading(0);
+    m_placement->reinitCascading();
     m_focusChain->removeDesktop(desktop);
 }