From 557476434427b29819a641dfe1989be4a7d7b6e3 Mon Sep 17 00:00:00 2001
From: liujiangtao <liujiangtao1@uniontech.com>
Date: Wed, 30 Sep 2026 13:28:13 +0800
Subject: [PATCH] perf(core): cache cursor output and emit it on change
MIME-Version: 1.0
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Add cursorOutputChanged(Output*) to RootSurfaceContainer and cache the
output under the cursor. The signal fires only when the output actually
changes, so LockScreen repositions its global login view on an output
switch instead of on every cursor motion.

为 RootSurfaceContainer 新增 cursorOutputChanged(Output*) 信号，并缓存
光标所在输出；仅在输出真正变化时发出。锁屏登录界面因此只在切换输出时
重新排布，而不再随每次鼠标移动触发。

Log: 新增光标输出变化信号并缓存，避免每次移动重排布
PMS: TASK-390751
Influence: cursorOutput() 改为读取缓存；锁屏登录界面仅在切换输出时重新排布。
---
 src/core/lockscreen.cpp           | 17 +++++------------
 src/core/lockscreen.h             |  1 -
 src/core/rootsurfacecontainer.cpp | 16 +++++++++++++++-
 src/core/rootsurfacecontainer.h   |  3 +++
 4 files changed, 23 insertions(+), 14 deletions(-)

diff --git a/src/core/lockscreen.cpp b/src/core/lockscreen.cpp
index ef14c2878..bf51df066 100644
--- a/src/core/lockscreen.cpp
+++ b/src/core/lockscreen.cpp
@@ -16,7 +16,6 @@
 #include "rootsurfacecontainer.h"
 #include "surfacewrapper.h"
 
-#include <wcursor.h>
 #include <wsessionlock.h>
 #include <wsessionlocksurface.h>
 #endif
@@ -37,12 +36,13 @@ LockScreen::LockScreen(ILockScreen *impl, SurfaceContainer *parent, GreeterProxy
 
     // The global login view is lazily created when this container becomes
     // visible (locked) and destroyed when it hides (unlocked). Track the
-    // cursor so the login UI follows the output the mouse is on.
+    // output under the cursor so the login UI follows the mouse without
+    // recomputing the output on every cursor motion.
     connect(this, &QQuickItem::visibleChanged, this, &LockScreen::onLoginViewVisibleChanged);
-    connect(rootContainer()->cursor(),
-            &WCursor::positionChanged,
+    connect(rootContainer(),
+            &RootSurfaceContainer::cursorOutputChanged,
             this,
-            &LockScreen::onCursorPositionChanged);
+            &LockScreen::repositionLoginView);
 }
 
 void LockScreen::lock()
@@ -243,13 +243,6 @@ void LockScreen::repositionLoginView()
     m_loginView->setWidth(size.width());
     m_loginView->setHeight(size.height());
 }
-
-void LockScreen::onCursorPositionChanged()
-{
-    if (m_loginView) {
-        repositionLoginView();
-    }
-}
 #if EXT_SESSION_LOCK_V1
 // ext_session_lock_v1 capabilities
 
diff --git a/src/core/lockscreen.h b/src/core/lockscreen.h
index dad4e3c98..ef07d69b9 100644
--- a/src/core/lockscreen.h
+++ b/src/core/lockscreen.h
@@ -80,7 +80,6 @@ private Q_SLOTS:
     void createLoginView();
     void destroyLoginView();
     void repositionLoginView();
-    void onCursorPositionChanged();
     Output *followerOutput() const;
 
     ILockScreen *m_impl{ nullptr };
diff --git a/src/core/rootsurfacecontainer.cpp b/src/core/rootsurfacecontainer.cpp
index 61851d025..12a17a96b 100644
--- a/src/core/rootsurfacecontainer.cpp
+++ b/src/core/rootsurfacecontainer.cpp
@@ -86,6 +86,9 @@ void RootSurfaceContainer::init(WServer *server)
             output->updatePositionFromLayout();
         }
         ensureCursorVisible();
+        // The layout may have moved/removed the output under the cursor, so
+        // refresh the cache even without a cursor motion event.
+        updateCursorOutput();
 
         // for (auto s : m_surfaceContainer->surfaces()) {
         //     ensureSurfaceNormalPositionValid(s);
@@ -101,6 +104,7 @@ void RootSurfaceContainer::init(WServer *server)
 
     QObject::connect(m_cursor, &WCursor::positionChanged, this, [this] {
         m_dragSurfaceItem->setPosition(m_cursor->position());
+        updateCursorOutput();
     });
 
     QObject::connect(m_cursor, &WCursor::requestedDragSurfaceChanged, this, [this] {
@@ -387,7 +391,17 @@ WCursor *RootSurfaceContainer::cursor() const
 Output *RootSurfaceContainer::cursorOutput() const
 {
     Q_ASSERT(m_cursor->layout() == m_outputLayout);
-    return outputAt(m_cursor->position());
+    return m_cursorOutput;
+}
+
+void RootSurfaceContainer::updateCursorOutput()
+{
+    Output *output = outputAt(m_cursor->position());
+    if (output == m_cursorOutput)
+        return;
+
+    m_cursorOutput = output;
+    Q_EMIT cursorOutputChanged(output);
 }
 
 Output *RootSurfaceContainer::outputAt(const QPointF &pos) const
diff --git a/src/core/rootsurfacecontainer.h b/src/core/rootsurfacecontainer.h
index 7091e73ed..f006542e3 100644
--- a/src/core/rootsurfacecontainer.h
+++ b/src/core/rootsurfacecontainer.h
@@ -121,6 +121,7 @@ public Q_SLOTS:
 
 Q_SIGNALS:
     void primaryOutputChanged();
+    void cursorOutputChanged(Output *output);
     void moveResizeFinised(SurfaceWrapper *surface);
 
 private:
@@ -138,6 +139,7 @@ public Q_SLOTS:
                                   [[maybe_unused]] SurfaceWrapper::State oldState) override;
 
     void ensureCursorVisible();
+    void updateCursorOutput();
     void updateSurfaceOutputs(SurfaceWrapper *surface);
     QQuickItem *ensureEdgeTilePreview();
     void onSeatAdded(WSeat *seat);
@@ -150,6 +152,7 @@ public Q_SLOTS:
     std::unique_ptr<WAYLIB_SERVER_NAMESPACE::WListenerOwner> m_outputLayoutListenerOwner;
     OutputListModel *m_outputModel = nullptr;
     QPointer<Output> m_primaryOutput;
+    QPointer<Output> m_cursorOutput;
     WCursor *m_cursor = nullptr;
     WSurfaceItem *m_dragSurfaceItem = nullptr;
     QPointer<QQuickItem> m_edgeTilePreview;