QPA offscreen: make platform plugin configurable

Add ability to load a json config file containing screen
configuration at startup. The config file location
is specified using platform options:

    -platform offscfreen:configfile=/path/to/file

Config file format example:
{
    “screens”: [
        {
        "name", "screen-1",
        "x", 0,
        "y", 0,
        "width", 640,
        "height", 480,
        "dpi", 96,
        "dpr", 1,
        },
        …
    ]
}

Change-Id: Iac21aaafa6d0f361bdd6f6e9168b7e68db6ae011
Reviewed-by: Paul Olav Tvete <paul.tvete@qt.io>
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@qt.io>

1 files changed, 12 insertions, 1 deletions

diff --git a/src/plugins/platforms/offscreen/qoffscreencommon.h b/src/plugins/platforms/offscreen/qoffscreencommon.h
index f4f0142911..abb641fbbc 100644
--- a/src/plugins/platforms/offscreen/qoffscreencommon.h
+++ b/src/plugins/platforms/offscreen/qoffscreencommon.h
@@ -54,23 +54,34 @@
 
 QT_BEGIN_NAMESPACE
 
+class QOffscreenIntegration;
 class QOffscreenScreen : public QPlatformScreen
 {
 public:
-    QOffscreenScreen();
+    QOffscreenScreen(const QOffscreenIntegration *integration);
 
     QRect geometry() const override { return m_geometry; }
     int depth() const override { return 32; }
     QImage::Format format() const override { return QImage::Format_RGB32; }
+    QDpi logicalDpi() const override { return QDpi(m_logicalDpi, m_logicalDpi); }
+    QDpi logicalBaseDpi() const override { return QDpi(m_logicalBaseDpi, m_logicalBaseDpi); }
+    qreal devicePixelRatio() const override { return m_dpr; }
+    QString name() const override { return m_name; }
     QPlatformCursor *cursor() const override { return m_cursor.data(); }
+    QList<QPlatformScreen *> virtualSiblings() const override;
 
     QPixmap grabWindow(WId window, int x, int y, int width, int height) const override;
 
     static QPlatformWindow *windowContainingCursor;
 
 public:
+    QString m_name;
     QRect m_geometry;
+    int m_logicalDpi = 96;
+    int m_logicalBaseDpi= 96;
+    qreal m_dpr = 1;
     QScopedPointer<QPlatformCursor> m_cursor;
+    const QOffscreenIntegration *m_integration;
 };
 
 #if QT_CONFIG(draganddrop)