Add physicalSize to the Screens API

Summary:
Allows to share the implementation in a better way and is a requirement
to get the Screen implementation in the QPA plugin to be based on
KWin::Screens instead of KWayland::Output.

Reviewers: #kwin, #plasma

Subscribers: plasma-devel, kwin

Tags: #kwin

Differential Revision: https://phabricator.kde.org/D8344

plugins/platforms/drm/drm_output.cpp

@@ -243,6 +243,7 @@ bool DrmOutput::init(drmModeConnector *connector)
         qCWarning(KWIN_DRM) << "Overwriting monitor physical size for" << m_edid.eisaId << "/" << m_edid.monitorName << "/" << m_edid.serialNumber << " from " << physicalSize << "to " << overwriteSize;
         physicalSize = overwriteSize;
     }
+    m_physicalSize = physicalSize;
     m_waylandOutput->setPhysicalSize(physicalSize);
     m_waylandOutputDevice->setPhysicalSize(physicalSize);
 

plugins/platforms/drm/drm_output.h

@@ -103,6 +103,10 @@ public:
         return m_uuid;
     }
 
+    QSize physicalSize() const {
+        return m_physicalSize;
+    }
+
 Q_SIGNALS:
     void dpmsChanged();
 
@@ -159,6 +163,7 @@ private:
     bool m_pageFlipPending = false;
     bool m_dpmsAtomicOffPending = false;
     bool m_modesetRequested = true;
+    QSize m_physicalSize;
 };
 
 }

plugins/platforms/drm/screens_drm.cpp

@@ -113,4 +113,13 @@ float DrmScreens::refreshRate(int screen) const
     return outputs.at(screen)->currentRefreshRate() / 1000.0f;
 }
 
+QSizeF DrmScreens::physicalSize(int screen) const
+{
+    const auto outputs = m_backend->outputs();
+    if (screen >= outputs.size()) {
+        return Screens::physicalSize(screen);
+    }
+    return outputs.at(screen)->physicalSize();
+}
+
 }

plugins/platforms/drm/screens_drm.h

@@ -40,6 +40,8 @@ public:
     QString name(int screen) const override;
     float refreshRate(int screen) const override;
 
+    QSizeF physicalSize(int screen) const override;
+
 private:
     DrmBackend *m_backend;
 };

plugins/platforms/hwcomposer/hwcomposer_backend.cpp

@@ -194,8 +194,9 @@ static KWayland::Server::OutputInterface *createOutput(hwc_composer_device_1_t *
 
     if (attr_values[2] != 0 && attr_values[3] != 0) {
          static const qreal factor = 25.4;
-         o->setPhysicalSize(QSizeF(qreal(pixel.width() * 1000) / qreal(attr_values[2]) * factor,
-                                   qreal(pixel.height() * 1000) / qreal(attr_values[3]) * factor).toSize());
+         m_physicalSize = QSizeF(qreal(pixel.width() * 1000) / qreal(attr_values[2]) * factor,
+                                 qreal(pixel.height() * 1000) / qreal(attr_values[3]) * factor);
+         o->setPhysicalSize(m_physicalSize.toSize());
     } else {
          // couldn't read physical size, assume 96 dpi
          o->setPhysicalSize(pixel / 3.8);

plugins/platforms/hwcomposer/hwcomposer_backend.h

@@ -85,6 +85,9 @@ public:
     QVector<CompositingType> supportedCompositors() const override {
         return QVector<CompositingType>{OpenGLCompositing};
     }
+    QSizeF physicalSize() const {
+        return m_physicalSize;
+    }
 
 Q_SIGNALS:
     void outputBlankChanged();
@@ -110,6 +113,7 @@ private:
     QMutex m_vsyncMutex;
     QWaitCondition m_vsyncWaitCondition;
     QScopedPointer<BacklightInputEventFilter> m_filter;
+    QSizeF m_physicalSize;
 };
 
 class HwcomposerWindow : public HWComposerNativeWindow

plugins/platforms/hwcomposer/screens_hwcomposer.cpp

@@ -37,4 +37,13 @@ float HwcomposerScreens::refreshRate(int screen) const
     return m_backend->refreshRate() / 1000.0f;
 }
 
+QSizeF HwcomposerScreens::physicalSize(int screen) const
+{
+    const QSizeF size = m_backend->physicalSize();
+    if (size.isValid()) {
+        return size;
+    }
+    return Screens::physicalSize(screen);
+}
+
 }

plugins/platforms/hwcomposer/screens_hwcomposer.h

@@ -32,6 +32,7 @@ public:
     HwcomposerScreens(HwcomposerBackend *backend, QObject *parent = nullptr);
     virtual ~HwcomposerScreens();
     float refreshRate(int screen) const override;
+    QSizeF physicalSize(int screen) const override;
 
 private:
     HwcomposerBackend *m_backend;

screens.cpp

@@ -190,6 +190,11 @@ QSize Screens::displaySize() const
     return size();
 }
 
+QSizeF Screens::physicalSize(int screen) const
+{
+    return QSizeF(size(screen)) / 3.8;
+}
+
 BasicScreens::BasicScreens(Platform *backend, QObject *parent)
     : Screens(parent)
     , m_backend(backend)

screens.h

@@ -117,6 +117,13 @@ public:
      **/
     virtual QSize displaySize() const;
 
+
+    /**
+     * The physical size of @p screen in mm.
+     * Default implementation returns a size derived from 96 DPI.
+     **/
+    virtual QSizeF physicalSize(int screen) const;
+
 public Q_SLOTS:
     void reconfigure();
 

wayland_server.cpp

@@ -414,7 +414,7 @@ void WaylandServer::syncOutputsToWayland()
         output->setScale(s->scale(i));
         const QRect &geo = s->geometry(i);
         output->setGlobalPosition(geo.topLeft());
-        output->setPhysicalSize(geo.size() / 3.8);
+        output->setPhysicalSize(s->physicalSize(i).toSize());
         output->addMode(geo.size());
         output->create();
     }