Make Scene::qpainterRenderBuffer() take a screen id

autotests/integration/scene_qpainter_test.cpp

@@ -105,7 +105,7 @@ void SceneQPainterTest::testStartFrame()
     const QImage cursorImage = cursor->image();
     QVERIFY(!cursorImage.isNull());
     p.drawImage(cursor->pos() - cursor->hotspot(), cursorImage);
-    QCOMPARE(referenceImage, *scene->qpainterRenderBuffer());
+    QCOMPARE(referenceImage, *scene->qpainterRenderBuffer(0));
 }
 
 void SceneQPainterTest::testCursorMoving()
@@ -136,7 +136,7 @@ void SceneQPainterTest::testCursorMoving()
     const QImage cursorImage = cursor->image();
     QVERIFY(!cursorImage.isNull());
     p.drawImage(QPoint(45, 45) - cursor->hotspot(), cursorImage);
-    QCOMPARE(referenceImage, *scene->qpainterRenderBuffer());
+    QCOMPARE(referenceImage, *scene->qpainterRenderBuffer(0));
 }
 
 void SceneQPainterTest::testWindow()
@@ -174,13 +174,13 @@ void SceneQPainterTest::testWindow()
     p->setCursor(cs.data(), QPoint(5, 5));
     QVERIFY(frameRenderedSpy.wait());
     painter.fillRect(KWin::Cursors::self()->mouse()->pos().x() - 5, KWin::Cursors::self()->mouse()->pos().y() - 5, 10, 10, Qt::red);
-    QCOMPARE(referenceImage, *scene->qpainterRenderBuffer());
+    QCOMPARE(referenceImage, *scene->qpainterRenderBuffer(0));
     // let's move the cursor again
     KWin::Cursors::self()->mouse()->setPos(10, 10);
     QVERIFY(frameRenderedSpy.wait());
     painter.fillRect(0, 0, 200, 300, Qt::blue);
     painter.fillRect(5, 5, 10, 10, Qt::red);
-    QCOMPARE(referenceImage, *scene->qpainterRenderBuffer());
+    QCOMPARE(referenceImage, *scene->qpainterRenderBuffer(0));
 }
 
 void SceneQPainterTest::testWindowScaled()
@@ -230,7 +230,7 @@ void SceneQPainterTest::testWindowScaled()
     painter.fillRect(100, 150, 100, 100, Qt::red);
     painter.fillRect(5, 5, 10, 10, Qt::red); //cursor
 
-    QCOMPARE(referenceImage, *scene->qpainterRenderBuffer());
+    QCOMPARE(referenceImage, *scene->qpainterRenderBuffer(0));
 }
 
 void SceneQPainterTest::testCompositorRestart()
@@ -274,7 +274,7 @@ void SceneQPainterTest::testCompositorRestart()
     const QImage cursorImage = cursor->image();
     QVERIFY(!cursorImage.isNull());
     painter.drawImage(QPoint(400, 400) - cursor->hotspot(), cursorImage);
-    QCOMPARE(referenceImage, *scene->qpainterRenderBuffer());
+    QCOMPARE(referenceImage, *scene->qpainterRenderBuffer(0));
 }
 
 struct XcbConnectionDeleter
@@ -348,7 +348,7 @@ void SceneQPainterTest::testX11Window()
     QVERIFY(frameRenderedSpy.wait());
 
     const QPoint startPos = client->pos() + client->clientPos();
-    auto image = scene->qpainterRenderBuffer();
+    auto image = scene->qpainterRenderBuffer(0);
     QCOMPARE(image->copy(QRect(startPos, client->clientSize())), compareImage);
 
     // and destroy the window again

plugins/scenes/qpainter/scene_qpainter.cpp

@@ -179,9 +179,9 @@ void SceneQPainter::screenGeometryChanged(const QSize &size)
     m_backend->screenGeometryChanged(size);
 }
 
-QImage *SceneQPainter::qpainterRenderBuffer() const
+QImage *SceneQPainter::qpainterRenderBuffer(int screenId) const
 {
-    return m_backend->bufferForScreen(0);
+    return m_backend->bufferForScreen(screenId);
 }
 
 //****************************************

plugins/scenes/qpainter/scene_qpainter.h

@@ -39,7 +39,7 @@ public:
     }
 
     QPainter *scenePainter() const override;
-    QImage *qpainterRenderBuffer() const override;
+    QImage *qpainterRenderBuffer(int screenId) const override;
 
     QPainterBackend *backend() const {
         return m_backend.data();

scene.cpp

@@ -692,8 +692,9 @@ QPainter *Scene::scenePainter() const
     return nullptr;
 }
 
-QImage *Scene::qpainterRenderBuffer() const
+QImage *Scene::qpainterRenderBuffer(int screenId) const
 {
+    Q_UNUSED(screenId)
     return nullptr;
 }
 

scene.h

@@ -179,7 +179,7 @@ public:
      * The render buffer used by a QPainter based compositor.
      * Default implementation returns @c nullptr.
      */
-    virtual QImage *qpainterRenderBuffer() const;
+    virtual QImage *qpainterRenderBuffer(int screenId) const;
 
     /**
      * The backend specific extensions (e.g. EGL/GLX extensions).