backends/x11: Remove initial position logic

Let kwin decide the output position. This makes the behavior of the
x11 backend consistent with the drm backend.

src/backends/x11/windowed/x11_windowed_backend.cpp

@@ -281,12 +281,10 @@ void X11WindowedBackend::createOutputs()
     // create an output window of this size in the end
     const int pixelWidth = initialWindowSize().width() * initialOutputScale() + 0.5;
     const int pixelHeight = initialWindowSize().height() * initialOutputScale() + 0.5;
-    const int logicalWidth = initialWindowSize().width();
 
-    int logicalWidthSum = 0;
     for (int i = 0; i < initialOutputCount(); ++i) {
         auto *output = new X11WindowedOutput(this);
-        output->init(QPoint(logicalWidthSum, 0), QSize(pixelWidth, pixelHeight));
+        output->init(QSize(pixelWidth, pixelHeight));
 
         m_protocols = protocolsAtom;
         m_deleteWindowProtocol = deleteWindowAtom;
@@ -299,7 +297,6 @@ void X11WindowedBackend::createOutputs()
                             32, 1,
                             &m_deleteWindowProtocol);
 
-        logicalWidthSum += logicalWidth;
         m_outputs << output;
         Q_EMIT outputAdded(output);
         output->setEnabled(true);
@@ -500,13 +497,6 @@ void X11WindowedBackend::handleClientMessage(xcb_client_message_event_t *event)
                 auto removedOutput = *it;
                 it = m_outputs.erase(it);
 
-                // update the sizes
-                int x = removedOutput->internalPosition().x();
-                for (; it != m_outputs.end(); ++it) {
-                    (*it)->setGeometry(QPoint(x, 0), (*it)->pixelSize());
-                    x += (*it)->geometry().width();
-                }
-
                 removedOutput->setEnabled(false);
                 Q_EMIT outputRemoved(removedOutput);
                 delete removedOutput;
@@ -590,7 +580,7 @@ void X11WindowedBackend::updateSize(xcb_configure_notify_event_t *event)
 
     const QSize s = QSize(event->width, event->height);
     if (s != output->pixelSize()) {
-        output->setGeometry(output->internalPosition(), s);
+        output->resize(s);
     }
     Q_EMIT sizeChanged();
 }

src/backends/x11/windowed/x11_windowed_output.cpp

@@ -74,13 +74,13 @@ SoftwareVsyncMonitor *X11WindowedOutput::vsyncMonitor() const
     return m_vsyncMonitor.get();
 }
 
-void X11WindowedOutput::init(const QPoint &logicalPosition, const QSize &pixelSize)
+void X11WindowedOutput::init(const QSize &pixelSize)
 {
     const int refreshRate = 60000; // TODO: get refresh rate via randr
     m_renderLoop->setRefreshRate(refreshRate);
     m_vsyncMonitor->setRefreshRate(refreshRate);
 
-    setGeometry(logicalPosition, pixelSize);
+    resize(pixelSize);
     setScale(m_backend->initialOutputScale());
 
     const uint32_t eventMask = XCB_EVENT_MASK_KEY_PRESS
@@ -157,12 +157,10 @@ void X11WindowedOutput::initXInputForWindow()
 #endif
 }
 
-void X11WindowedOutput::setGeometry(const QPoint &logicalPosition, const QSize &pixelSize)
+void X11WindowedOutput::resize(const QSize &pixelSize)
 {
     auto mode = std::make_shared<OutputMode>(pixelSize, m_renderLoop->refreshRate());
     setModesInternal({mode}, mode);
-
-    moveTo(logicalPosition);
 }
 
 void X11WindowedOutput::setWindowTitle(const QString &title)

src/backends/x11/windowed/x11_windowed_output.h

@@ -38,7 +38,8 @@ public:
     RenderLoop *renderLoop() const override;
     SoftwareVsyncMonitor *vsyncMonitor() const;
 
-    void init(const QPoint &logicalPosition, const QSize &pixelSize);
+    void init(const QSize &pixelSize);
+    void resize(const QSize &pixelSize);
 
     xcb_window_t window() const
     {
@@ -54,13 +55,6 @@ public:
 
     void setWindowTitle(const QString &title);
 
-    /**
-     * @brief defines the geometry of the output
-     * @param logicalPosition top left position of the output in compositor space
-     * @param pixelSize output size as seen from the outside
-     */
-    void setGeometry(const QPoint &logicalPosition, const QSize &pixelSize);
-
     /**
      * Translates the global X11 screen coordinate @p pos to output coordinates.
      */