From c74fa4b571727dbcea901780314aef51aefd6e01 Mon Sep 17 00:00:00 2001
From: Vlad Zahorodnii <vlad.zahorodnii@kde.org>
Date: Thu, 14 Jul 2022 10:04:43 +0300
Subject: [PATCH] backends/x11: Port windowed backend from Screens

---
 src/backends/x11/windowed/egl_x11_backend.cpp |  1 -
 .../windowed/scene_qpainter_x11_backend.cpp   | 23 +++++++++++--------
 .../x11/windowed/scene_qpainter_x11_backend.h |  4 +++-
 .../x11/windowed/x11windowed_backend.cpp      |  3 +--
 4 files changed, 18 insertions(+), 13 deletions(-)

diff --git a/src/backends/x11/windowed/egl_x11_backend.cpp b/src/backends/x11/windowed/egl_x11_backend.cpp
index b83ff1a210..5d095d2ea3 100644
--- a/src/backends/x11/windowed/egl_x11_backend.cpp
+++ b/src/backends/x11/windowed/egl_x11_backend.cpp
@@ -11,7 +11,6 @@
 #include "basiceglsurfacetexture_internal.h"
 #include "basiceglsurfacetexture_wayland.h"
 #include "main.h"
-#include "screens.h"
 #include "softwarevsyncmonitor.h"
 #include "x11windowed_backend.h"
 #include "x11windowed_output.h"
diff --git a/src/backends/x11/windowed/scene_qpainter_x11_backend.cpp b/src/backends/x11/windowed/scene_qpainter_x11_backend.cpp
index e535b111fa..f646e4be08 100644
--- a/src/backends/x11/windowed/scene_qpainter_x11_backend.cpp
+++ b/src/backends/x11/windowed/scene_qpainter_x11_backend.cpp
@@ -8,7 +8,6 @@
 */
 #include "scene_qpainter_x11_backend.h"
 #include "main.h"
-#include "screens.h"
 #include "softwarevsyncmonitor.h"
 #include "x11windowed_backend.h"
 #include "x11windowed_output.h"
@@ -52,8 +51,13 @@ X11WindowedQPainterBackend::X11WindowedQPainterBackend(X11WindowedBackend *backe
     : QPainterBackend()
     , m_backend(backend)
 {
-    connect(screens(), &Screens::changed, this, &X11WindowedQPainterBackend::createOutputs);
-    createOutputs();
+    const auto outputs = m_backend->enabledOutputs();
+    for (Output *output : outputs) {
+        addOutput(output);
+    }
+
+    connect(backend, &X11WindowedBackend::outputEnabled, this, &X11WindowedQPainterBackend::addOutput);
+    connect(backend, &X11WindowedBackend::outputDisabled, this, &X11WindowedQPainterBackend::removeOutput);
 }
 
 X11WindowedQPainterBackend::~X11WindowedQPainterBackend()
@@ -64,13 +68,14 @@ X11WindowedQPainterBackend::~X11WindowedQPainterBackend()
     }
 }
 
-void X11WindowedQPainterBackend::createOutputs()
+void X11WindowedQPainterBackend::addOutput(Output *output)
 {
-    m_outputs.clear();
-    const auto &outputs = m_backend->outputs();
-    for (const auto &x11Output : outputs) {
-        m_outputs[x11Output] = std::make_shared<X11WindowedQPainterOutput>(x11Output, m_backend->windowForScreen(x11Output));
-    }
+    m_outputs[output] = std::make_shared<X11WindowedQPainterOutput>(output, m_backend->windowForScreen(output));
+}
+
+void X11WindowedQPainterBackend::removeOutput(Output *output)
+{
+    m_outputs.remove(output);
 }
 
 void X11WindowedQPainterBackend::present(Output *output)
diff --git a/src/backends/x11/windowed/scene_qpainter_x11_backend.h b/src/backends/x11/windowed/scene_qpainter_x11_backend.h
index eb7996eec9..b05ca3d010 100644
--- a/src/backends/x11/windowed/scene_qpainter_x11_backend.h
+++ b/src/backends/x11/windowed/scene_qpainter_x11_backend.h
@@ -50,7 +50,9 @@ public:
     OutputLayer *primaryLayer(Output *output) override;
 
 private:
-    void createOutputs();
+    void addOutput(Output *output);
+    void removeOutput(Output *output);
+
     xcb_gcontext_t m_gc = XCB_NONE;
     X11WindowedBackend *m_backend;
     QMap<Output *, std::shared_ptr<X11WindowedQPainterOutput>> m_outputs;
diff --git a/src/backends/x11/windowed/x11windowed_backend.cpp b/src/backends/x11/windowed/x11windowed_backend.cpp
index dfcff56519..5bb3b37bb5 100644
--- a/src/backends/x11/windowed/x11windowed_backend.cpp
+++ b/src/backends/x11/windowed/x11windowed_backend.cpp
@@ -13,7 +13,6 @@
 #include "egl_x11_backend.h"
 #include "logging.h"
 #include "scene_qpainter_x11_backend.h"
-#include "screens.h"
 #include "session.h"
 #include "utils/xcbutils.h"
 #include "wayland_server.h"
@@ -516,7 +515,7 @@ void X11WindowedBackend::handleClientMessage(xcb_client_message_event_t *event)
                 Q_EMIT outputDisabled(removedOutput);
                 Q_EMIT outputRemoved(removedOutput);
                 delete removedOutput;
-                QMetaObject::invokeMethod(screens(), "updateCount");
+                Q_EMIT screensQueried();
             }
         }
     }