diff --git a/src/scene/decorationitem.cpp b/src/scene/decorationitem.cpp
index da28cea937..9ef6510965 100644
--- a/src/scene/decorationitem.cpp
+++ b/src/scene/decorationitem.cpp
@@ -11,16 +11,12 @@
 #include "decorations/decoratedclient.h"
 #include "deleted.h"
 #include "scene/workspacescene.h"
-#include "utils/common.h"
-#include "window.h"
 
 #include <cmath>
 
 #include <KDecoration2/DecoratedClient>
 #include <KDecoration2/Decoration>
 
-#include <QPainter>
-
 namespace KWin
 {
 
@@ -87,38 +83,6 @@ void DecorationRenderer::setDevicePixelRatio(qreal dpr)
     }
 }
 
-QImage DecorationRenderer::renderToImage(const QRect &geo)
-{
-    Q_ASSERT(m_client);
-
-    // Guess the pixel format of the X pixmap into which the QImage will be copied.
-    QImage::Format format;
-    const int depth = client()->window()->depth();
-    switch (depth) {
-    case 30:
-        format = QImage::Format_A2RGB30_Premultiplied;
-        break;
-    case 24:
-    case 32:
-        format = QImage::Format_ARGB32_Premultiplied;
-        break;
-    default:
-        qCCritical(KWIN_CORE) << "Unsupported client depth" << depth;
-        format = QImage::Format_ARGB32_Premultiplied;
-        break;
-    };
-
-    QImage image(geo.width() * m_devicePixelRatio, geo.height() * m_devicePixelRatio, format);
-    image.setDevicePixelRatio(m_devicePixelRatio);
-    image.fill(Qt::transparent);
-    QPainter p(&image);
-    p.setRenderHint(QPainter::Antialiasing);
-    p.setWindow(QRect(geo.topLeft(), geo.size() * effectiveDevicePixelRatio()));
-    p.setClipRect(geo);
-    renderToPainter(&p, geo);
-    return image;
-}
-
 void DecorationRenderer::renderToPainter(QPainter *painter, const QRect &rect)
 {
     client()->decoration()->paint(painter, rect);
diff --git a/src/scene/decorationitem.h b/src/scene/decorationitem.h
index 64a6fb6778..af743e5156 100644
--- a/src/scene/decorationitem.h
+++ b/src/scene/decorationitem.h
@@ -61,7 +61,6 @@ protected:
     {
         m_imageSizesDirty = false;
     }
-    QImage renderToImage(const QRect &geo);
     void renderToPainter(QPainter *painter, const QRect &rect);
 
 private:
diff --git a/src/x11window.cpp b/src/x11window.cpp
index 5a38b1961e..e917fc9648 100644
--- a/src/x11window.cpp
+++ b/src/x11window.cpp
@@ -46,6 +46,7 @@
 #include <QFile>
 #include <QFileInfo>
 #include <QMouseEvent>
+#include <QPainter>
 #include <QProcess>
 // xcb
 #include <xcb/xcb_icccm.h>
@@ -194,7 +195,32 @@ void X11DecorationRenderer::render(const QRegion &region)
         if (!geo.isValid()) {
             return;
         }
-        QImage image = renderToImage(geo);
+
+        // Guess the pixel format of the X pixmap into which the QImage will be copied.
+        QImage::Format format;
+        const int depth = client()->window()->depth();
+        switch (depth) {
+        case 30:
+            format = QImage::Format_A2RGB30_Premultiplied;
+            break;
+        case 24:
+        case 32:
+            format = QImage::Format_ARGB32_Premultiplied;
+            break;
+        default:
+            qCCritical(KWIN_CORE) << "Unsupported client depth" << depth;
+            format = QImage::Format_ARGB32_Premultiplied;
+            break;
+        };
+
+        QImage image(geo.width(), geo.height(), format);
+        image.fill(Qt::transparent);
+        QPainter p(&image);
+        p.setRenderHint(QPainter::Antialiasing);
+        p.setWindow(geo);
+        p.setClipRect(geo);
+        renderToPainter(&p, geo);
+
         xcb_put_image(c, XCB_IMAGE_FORMAT_Z_PIXMAP, client()->window()->frameId(), m_gc,
                       image.width(), image.height(), geo.x(), geo.y(), 0, client()->window()->depth(),
                       image.sizeInBytes(), image.constBits());