rhi: Add explicit subclass for RTs from swapchains

We want to enable gaining access to the underlying resource(s) by
inspecting a QRhiRenderTarget. This is not currently possible for
swapchains since there is nothing that references the actual
QRhiSwapChain. To clean this up, make an explicit, new
QRhiSwapChainRenderTarget subclass. Thus the logic already used in a
couple of places to examine the resources attached to a
QRhiTextureRenderTarget can now work with swapchain render targets too,
by branching based on the resourceType().

This eliminates the somewhat odd setup where a "RenderTarget" resource
is QRhiRenderTarget corresponding (but not exposing!) a swapchain,
whereas a "TextureRenderTarget" is a QRhiTextureRenderTarget which
is a subclass of QRhiRenderTarget. Now we correctly have an (abstract)
base and two subclasses, one for each type of render targets.

Besides, it allows us to clean up the oddly named
Q...ReferenceRenderTarget classes in the backends, which initially tried
to indicate that this "render target" merely references (or, in
practice, is) a swapchain. We can now have a nice and symmetrical
Q...SwapChainRenderTarget and Q...TextureRenderTarget naming scheme.

Change-Id: Ib07e9be99a316eec67b94de0860e08f5f4638959
Reviewed-by: Andy Nichols <andy.nichols@qt.io>

12 files changed, 128 insertions, 84 deletions

diff --git a/src/gui/rhi/qrhi.cpp b/src/gui/rhi/qrhi.cpp
index adf7b781ff..4ed9370fa2 100644
--- a/src/gui/rhi/qrhi.cpp
+++ b/src/gui/rhi/qrhi.cpp
@@ -2943,6 +2943,8 @@ const QRhiNativeHandles *QRhiRenderPassDescriptor::nativeHandles()
     \internal
     \inmodule QtGui
     \brief Represents an onscreen (swapchain) or offscreen (texture) render target.
+
+    \sa QRhiSwapChainRenderTarget, QRhiTextureRenderTarget
  */
 
 /*!
@@ -2954,14 +2956,6 @@ QRhiRenderTarget::QRhiRenderTarget(QRhiImplementation *rhi)
 }
 
 /*!
-    \return the resource type.
- */
-QRhiResource::Type QRhiRenderTarget::resourceType() const
-{
-    return RenderTarget;
-}
-
-/*!
     \fn QSize QRhiRenderTarget::pixelSize() const
 
     \return the size in pixels.
@@ -2989,6 +2983,42 @@ QRhiResource::Type QRhiRenderTarget::resourceType() const
  */
 
 /*!
+    \internal
+ */
+QRhiSwapChainRenderTarget::QRhiSwapChainRenderTarget(QRhiImplementation *rhi, QRhiSwapChain *swapchain_)
+    : QRhiRenderTarget(rhi),
+      m_swapchain(swapchain_)
+{
+}
+
+/*!
+    \class QRhiSwapChainRenderTarget
+    \internal
+    \inmodule QtGui
+    \brief Swapchain render target resource.
+
+    When targeting the color buffers of a swapchain, active render target is a
+    QRhiSwapChainRenderTarget. This is what
+    QRhiSwapChain::currentFrameRenderTarget() returns.
+
+    \sa QRhiSwapChain
+ */
+
+/*!
+    \return the resource type.
+ */
+QRhiResource::Type QRhiSwapChainRenderTarget::resourceType() const
+{
+    return SwapChainRenderTarget;
+}
+
+/*!
+    \fn QRhiSwapChain *QRhiSwapChainRenderTarget::swapChain() const
+
+    \return the swapchain object.
+ */
+
+/*!
     \class QRhiTextureRenderTarget
     \internal
     \inmodule QtGui
@@ -2997,6 +3027,10 @@ QRhiResource::Type QRhiRenderTarget::resourceType() const
     A texture render target allows rendering into one or more textures,
     optionally with a depth texture or depth/stencil renderbuffer.
 
+    For multisample rendering the common approach is to use a renderbuffer as
+    the color attachment and set the non-multisample destination texture as the
+    \c{resolve texture}.
+
     \note Textures used in combination with QRhiTextureRenderTarget must be
     created with the QRhiTexture::RenderTarget flag.
 
@@ -4911,8 +4945,8 @@ static const char *resourceTypeStr(QRhiResource *res)
         return "RenderBuffer";
     case QRhiResource::RenderPassDescriptor:
         return "RenderPassDescriptor";
-    case QRhiResource::RenderTarget:
-        return "RenderTarget";
+    case QRhiResource::SwapChainRenderTarget:
+        return "SwapChainRenderTarget";
     case QRhiResource::TextureRenderTarget:
         return "TextureRenderTarget";
     case QRhiResource::ShaderResourceBindings:
diff --git a/src/gui/rhi/qrhi_p.h b/src/gui/rhi/qrhi_p.h
index 07f3ad69be..bbc404f09b 100644
--- a/src/gui/rhi/qrhi_p.h
+++ b/src/gui/rhi/qrhi_p.h
@@ -74,6 +74,7 @@ class QRhiSampler;
 class QRhiCommandBuffer;
 class QRhiResourceUpdateBatch;
 class QRhiResourceUpdateBatchPrivate;
+class QRhiSwapChain;
 
 class Q_GUI_EXPORT QRhiDepthStencilClearValue
 {
@@ -697,7 +698,7 @@ public:
         Sampler,
         RenderBuffer,
         RenderPassDescriptor,
-        RenderTarget,
+        SwapChainRenderTarget,
         TextureRenderTarget,
         ShaderResourceBindings,
         GraphicsPipeline,
@@ -1031,8 +1032,6 @@ protected:
 class Q_GUI_EXPORT QRhiRenderTarget : public QRhiResource
 {
 public:
-    QRhiResource::Type resourceType() const override;
-
     virtual QSize pixelSize() const = 0;
     virtual float devicePixelRatio() const = 0;
     virtual int sampleCount() const = 0;
@@ -1045,6 +1044,17 @@ protected:
     QRhiRenderPassDescriptor *m_renderPassDesc = nullptr;
 };
 
+class Q_GUI_EXPORT QRhiSwapChainRenderTarget : public QRhiRenderTarget
+{
+public:
+    QRhiResource::Type resourceType() const override;
+    QRhiSwapChain *swapChain() const { return m_swapchain; }
+
+protected:
+    QRhiSwapChainRenderTarget(QRhiImplementation *rhi, QRhiSwapChain *swapchain_);
+    QRhiSwapChain *m_swapchain;
+};
+
 class Q_GUI_EXPORT QRhiTextureRenderTarget : public QRhiRenderTarget
 {
 public:
diff --git a/src/gui/rhi/qrhid3d11.cpp b/src/gui/rhi/qrhid3d11.cpp
index 3fde58af8e..f6e07f347e 100644
--- a/src/gui/rhi/qrhid3d11.cpp
+++ b/src/gui/rhi/qrhid3d11.cpp
@@ -1759,8 +1759,8 @@ void QRhiD3D11::finishActiveReadbacks()
 static inline QD3D11RenderTargetData *rtData(QRhiRenderTarget *rt)
 {
     switch (rt->resourceType()) {
-    case QRhiResource::RenderTarget:
-        return &QRHI_RES(QD3D11ReferenceRenderTarget, rt)->d;
+    case QRhiResource::SwapChainRenderTarget:
+        return &QRHI_RES(QD3D11SwapChainRenderTarget, rt)->d;
     case QRhiResource::TextureRenderTarget:
         return &QRHI_RES(QD3D11TextureRenderTarget, rt)->d;
     default:
@@ -3453,33 +3453,33 @@ QVector<quint32> QD3D11RenderPassDescriptor::serializedFormat() const
     return {};
 }
 
-QD3D11ReferenceRenderTarget::QD3D11ReferenceRenderTarget(QRhiImplementation *rhi)
-    : QRhiRenderTarget(rhi),
+QD3D11SwapChainRenderTarget::QD3D11SwapChainRenderTarget(QRhiImplementation *rhi, QRhiSwapChain *swapchain)
+    : QRhiSwapChainRenderTarget(rhi, swapchain),
       d(rhi)
 {
 }
 
-QD3D11ReferenceRenderTarget::~QD3D11ReferenceRenderTarget()
+QD3D11SwapChainRenderTarget::~QD3D11SwapChainRenderTarget()
 {
     destroy();
 }
 
-void QD3D11ReferenceRenderTarget::destroy()
+void QD3D11SwapChainRenderTarget::destroy()
 {
     // nothing to do here
 }
 
-QSize QD3D11ReferenceRenderTarget::pixelSize() const
+QSize QD3D11SwapChainRenderTarget::pixelSize() const
 {
     return d.pixelSize;
 }
 
-float QD3D11ReferenceRenderTarget::devicePixelRatio() const
+float QD3D11SwapChainRenderTarget::devicePixelRatio() const
 {
     return d.dpr;
 }
 
-int QD3D11ReferenceRenderTarget::sampleCount() const
+int QD3D11SwapChainRenderTarget::sampleCount() const
 {
     return d.sampleCount;
 }
@@ -4380,7 +4380,7 @@ void QD3D11CommandBuffer::destroy()
 
 QD3D11SwapChain::QD3D11SwapChain(QRhiImplementation *rhi)
     : QRhiSwapChain(rhi),
-      rt(rhi),
+      rt(rhi, this),
       cb(rhi)
 {
     backBufferTex = nullptr;
@@ -4825,7 +4825,7 @@ bool QD3D11SwapChain::createOrResize()
     frameCount = 0;
     ds = m_depthStencil ? QRHI_RES(QD3D11RenderBuffer, m_depthStencil) : nullptr;
 
-    QD3D11ReferenceRenderTarget *rtD = QRHI_RES(QD3D11ReferenceRenderTarget, &rt);
+    QD3D11SwapChainRenderTarget *rtD = QRHI_RES(QD3D11SwapChainRenderTarget, &rt);
     rtD->d.rp = QRHI_RES(QD3D11RenderPassDescriptor, m_renderPassDesc);
     rtD->d.pixelSize = pixelSize;
     rtD->d.dpr = float(window->devicePixelRatio());
diff --git a/src/gui/rhi/qrhid3d11_p_p.h b/src/gui/rhi/qrhid3d11_p_p.h
index 9e12defbfd..76a40ebce6 100644
--- a/src/gui/rhi/qrhid3d11_p_p.h
+++ b/src/gui/rhi/qrhid3d11_p_p.h
@@ -177,10 +177,10 @@ struct QD3D11RenderTargetData
     QRhiRenderTargetAttachmentTracker::ResIdList currentResIdList;
 };
 
-struct QD3D11ReferenceRenderTarget : public QRhiRenderTarget
+struct QD3D11SwapChainRenderTarget : public QRhiSwapChainRenderTarget
 {
-    QD3D11ReferenceRenderTarget(QRhiImplementation *rhi);
-    ~QD3D11ReferenceRenderTarget();
+    QD3D11SwapChainRenderTarget(QRhiImplementation *rhi, QRhiSwapChain *swapchain);
+    ~QD3D11SwapChainRenderTarget();
     void destroy() override;
 
     QSize pixelSize() const override;
@@ -571,7 +571,7 @@ struct QD3D11SwapChain : public QRhiSwapChain
 
     QWindow *window = nullptr;
     QSize pixelSize;
-    QD3D11ReferenceRenderTarget rt;
+    QD3D11SwapChainRenderTarget rt;
     QD3D11CommandBuffer cb;
     DXGI_FORMAT colorFormat;
     DXGI_FORMAT srgbAdjustedColorFormat;
diff --git a/src/gui/rhi/qrhigles2.cpp b/src/gui/rhi/qrhigles2.cpp
index 94844cbb66..cbafa95f5d 100644
--- a/src/gui/rhi/qrhigles2.cpp
+++ b/src/gui/rhi/qrhigles2.cpp
@@ -3953,8 +3953,8 @@ QGles2RenderTargetData *QRhiGles2::enqueueBindFramebuffer(QRhiRenderTarget *rt,
     static const bool doClearColorBuffer = qEnvironmentVariableIntValue("QT_GL_NO_CLEAR_COLOR_BUFFER") == 0;
 
     switch (rt->resourceType()) {
-    case QRhiResource::RenderTarget:
-        rtD = &QRHI_RES(QGles2ReferenceRenderTarget, rt)->d;
+    case QRhiResource::SwapChainRenderTarget:
+        rtD = &QRHI_RES(QGles2SwapChainRenderTarget, rt)->d;
         if (wantsColorClear)
             *wantsColorClear = doClearBuffers && doClearColorBuffer;
         if (wantsDsClear)
@@ -5196,33 +5196,33 @@ QVector<quint32> QGles2RenderPassDescriptor::serializedFormat() const
     return {};
 }
 
-QGles2ReferenceRenderTarget::QGles2ReferenceRenderTarget(QRhiImplementation *rhi)
-    : QRhiRenderTarget(rhi),
+QGles2SwapChainRenderTarget::QGles2SwapChainRenderTarget(QRhiImplementation *rhi, QRhiSwapChain *swapchain)
+    : QRhiSwapChainRenderTarget(rhi, swapchain),
       d(rhi)
 {
 }
 
-QGles2ReferenceRenderTarget::~QGles2ReferenceRenderTarget()
+QGles2SwapChainRenderTarget::~QGles2SwapChainRenderTarget()
 {
     destroy();
 }
 
-void QGles2ReferenceRenderTarget::destroy()
+void QGles2SwapChainRenderTarget::destroy()
 {
     // nothing to do here
 }
 
-QSize QGles2ReferenceRenderTarget::pixelSize() const
+QSize QGles2SwapChainRenderTarget::pixelSize() const
 {
     return d.pixelSize;
 }
 
-float QGles2ReferenceRenderTarget::devicePixelRatio() const
+float QGles2SwapChainRenderTarget::devicePixelRatio() const
 {
     return d.dpr;
 }
 
-int QGles2ReferenceRenderTarget::sampleCount() const
+int QGles2SwapChainRenderTarget::sampleCount() const
 {
     return d.sampleCount;
 }
@@ -5731,7 +5731,7 @@ void QGles2CommandBuffer::destroy()
 
 QGles2SwapChain::QGles2SwapChain(QRhiImplementation *rhi)
     : QRhiSwapChain(rhi),
-      rt(rhi),
+      rt(rhi, this),
       cb(rhi)
 {
 }
diff --git a/src/gui/rhi/qrhigles2_p_p.h b/src/gui/rhi/qrhigles2_p_p.h
index 3af4178a24..3fbdb8dceb 100644
--- a/src/gui/rhi/qrhigles2_p_p.h
+++ b/src/gui/rhi/qrhigles2_p_p.h
@@ -219,10 +219,10 @@ struct QGles2RenderTargetData
     QRhiRenderTargetAttachmentTracker::ResIdList currentResIdList;
 };
 
-struct QGles2ReferenceRenderTarget : public QRhiRenderTarget
+struct QGles2SwapChainRenderTarget : public QRhiSwapChainRenderTarget
 {
-    QGles2ReferenceRenderTarget(QRhiImplementation *rhi);
-    ~QGles2ReferenceRenderTarget();
+    QGles2SwapChainRenderTarget(QRhiImplementation *rhi, QRhiSwapChain *swapchain);
+    ~QGles2SwapChainRenderTarget();
     void destroy() override;
 
     QSize pixelSize() const override;
@@ -735,7 +735,7 @@ struct QGles2SwapChain : public QRhiSwapChain
 
     QSurface *surface = nullptr;
     QSize pixelSize;
-    QGles2ReferenceRenderTarget rt;
+    QGles2SwapChainRenderTarget rt;
     QGles2CommandBuffer cb;
     int frameCount = 0;
 };
diff --git a/src/gui/rhi/qrhimetal.mm b/src/gui/rhi/qrhimetal.mm
index 72145b39e8..be38e92bcc 100644
--- a/src/gui/rhi/qrhimetal.mm
+++ b/src/gui/rhi/qrhimetal.mm
@@ -2032,8 +2032,8 @@ void QRhiMetal::beginPass(QRhiCommandBuffer *cb,
 
     QMetalRenderTargetData *rtD = nullptr;
     switch (rt->resourceType()) {
-    case QRhiResource::RenderTarget:
-        rtD = QRHI_RES(QMetalReferenceRenderTarget, rt)->d;
+    case QRhiResource::SwapChainRenderTarget:
+        rtD = QRHI_RES(QMetalSwapChainRenderTarget, rt)->d;
         cbD->d->currentPassRpDesc = d->createDefaultRenderPass(rtD->dsAttCount, colorClearValue, depthStencilClearValue, rtD->colorAttCount);
         if (rtD->colorAttCount) {
             QMetalRenderTargetData::ColorAtt &color0(rtD->fb.colorAtt[0]);
@@ -3053,34 +3053,34 @@ QVector<quint32> QMetalRenderPassDescriptor::serializedFormat() const
     return serializedFormatData;
 }
 
-QMetalReferenceRenderTarget::QMetalReferenceRenderTarget(QRhiImplementation *rhi)
-    : QRhiRenderTarget(rhi),
+QMetalSwapChainRenderTarget::QMetalSwapChainRenderTarget(QRhiImplementation *rhi, QRhiSwapChain *swapchain)
+    : QRhiSwapChainRenderTarget(rhi, swapchain),
       d(new QMetalRenderTargetData)
 {
 }
 
-QMetalReferenceRenderTarget::~QMetalReferenceRenderTarget()
+QMetalSwapChainRenderTarget::~QMetalSwapChainRenderTarget()
 {
     destroy();
     delete d;
 }
 
-void QMetalReferenceRenderTarget::destroy()
+void QMetalSwapChainRenderTarget::destroy()
 {
     // nothing to do here
 }
 
-QSize QMetalReferenceRenderTarget::pixelSize() const
+QSize QMetalSwapChainRenderTarget::pixelSize() const
 {
     return d->pixelSize;
 }
 
-float QMetalReferenceRenderTarget::devicePixelRatio() const
+float QMetalSwapChainRenderTarget::devicePixelRatio() const
 {
     return d->dpr;
 }
 
-int QMetalReferenceRenderTarget::sampleCount() const
+int QMetalSwapChainRenderTarget::sampleCount() const
 {
     return d->sampleCount;
 }
@@ -3947,7 +3947,7 @@ void QMetalCommandBuffer::resetPerPassCachedState()
 
 QMetalSwapChain::QMetalSwapChain(QRhiImplementation *rhi)
     : QRhiSwapChain(rhi),
-      rtWrapper(rhi),
+      rtWrapper(rhi, this),
       cbWrapper(rhi),
       d(new QMetalSwapChainData)
 {
diff --git a/src/gui/rhi/qrhimetal_p_p.h b/src/gui/rhi/qrhimetal_p_p.h
index f96ddbe209..cbb6e537b5 100644
--- a/src/gui/rhi/qrhimetal_p_p.h
+++ b/src/gui/rhi/qrhimetal_p_p.h
@@ -163,10 +163,10 @@ struct QMetalRenderPassDescriptor : public QRhiRenderPassDescriptor
 
 struct QMetalRenderTargetData;
 
-struct QMetalReferenceRenderTarget : public QRhiRenderTarget
+struct QMetalSwapChainRenderTarget : public QRhiSwapChainRenderTarget
 {
-    QMetalReferenceRenderTarget(QRhiImplementation *rhi);
-    ~QMetalReferenceRenderTarget();
+    QMetalSwapChainRenderTarget(QRhiImplementation *rhi, QRhiSwapChain *swapchain);
+    ~QMetalSwapChainRenderTarget();
     void destroy() override;
 
     QSize pixelSize() const override;
@@ -337,7 +337,7 @@ struct QMetalSwapChain : public QRhiSwapChain
     int currentFrameSlot = 0; // 0..QMTL_FRAMES_IN_FLIGHT-1
     int frameCount = 0;
     int samples = 1;
-    QMetalReferenceRenderTarget rtWrapper;
+    QMetalSwapChainRenderTarget rtWrapper;
     QMetalCommandBuffer cbWrapper;
     QMetalRenderBuffer *ds = nullptr;
     QMetalSwapChainData *d = nullptr;
diff --git a/src/gui/rhi/qrhinull.cpp b/src/gui/rhi/qrhinull.cpp
index 7136c7e73f..f567894a9e 100644
--- a/src/gui/rhi/qrhinull.cpp
+++ b/src/gui/rhi/qrhinull.cpp
@@ -788,32 +788,32 @@ QVector<quint32> QNullRenderPassDescriptor::serializedFormat() const
     return {};
 }
 
-QNullReferenceRenderTarget::QNullReferenceRenderTarget(QRhiImplementation *rhi)
-    : QRhiRenderTarget(rhi),
+QNullSwapChainRenderTarget::QNullSwapChainRenderTarget(QRhiImplementation *rhi, QRhiSwapChain *swapchain)
+    : QRhiSwapChainRenderTarget(rhi, swapchain),
       d(rhi)
 {
 }
 
-QNullReferenceRenderTarget::~QNullReferenceRenderTarget()
+QNullSwapChainRenderTarget::~QNullSwapChainRenderTarget()
 {
     destroy();
 }
 
-void QNullReferenceRenderTarget::destroy()
+void QNullSwapChainRenderTarget::destroy()
 {
 }
 
-QSize QNullReferenceRenderTarget::pixelSize() const
+QSize QNullSwapChainRenderTarget::pixelSize() const
 {
     return d.pixelSize;
 }
 
-float QNullReferenceRenderTarget::devicePixelRatio() const
+float QNullSwapChainRenderTarget::devicePixelRatio() const
 {
     return d.dpr;
 }
 
-int QNullReferenceRenderTarget::sampleCount() const
+int QNullSwapChainRenderTarget::sampleCount() const
 {
     return 1;
 }
@@ -965,7 +965,7 @@ void QNullCommandBuffer::destroy()
 
 QNullSwapChain::QNullSwapChain(QRhiImplementation *rhi)
     : QRhiSwapChain(rhi),
-      rt(rhi),
+      rt(rhi, this),
       cb(rhi)
 {
 }
diff --git a/src/gui/rhi/qrhinull_p_p.h b/src/gui/rhi/qrhinull_p_p.h
index 90c448dd24..b43cbc7687 100644
--- a/src/gui/rhi/qrhinull_p_p.h
+++ b/src/gui/rhi/qrhinull_p_p.h
@@ -124,10 +124,10 @@ struct QNullRenderTargetData
     QRhiRenderTargetAttachmentTracker::ResIdList currentResIdList;
 };
 
-struct QNullReferenceRenderTarget : public QRhiRenderTarget
+struct QNullSwapChainRenderTarget : public QRhiSwapChainRenderTarget
 {
-    QNullReferenceRenderTarget(QRhiImplementation *rhi);
-    ~QNullReferenceRenderTarget();
+    QNullSwapChainRenderTarget(QRhiImplementation *rhi, QRhiSwapChain *swapchain);
+    ~QNullSwapChainRenderTarget();
     void destroy() override;
 
     QSize pixelSize() const override;
@@ -201,7 +201,7 @@ struct QNullSwapChain : public QRhiSwapChain
     bool createOrResize() override;
 
     QWindow *window = nullptr;
-    QNullReferenceRenderTarget rt;
+    QNullSwapChainRenderTarget rt;
     QNullCommandBuffer cb;
     int frameCount = 0;
 };
diff --git a/src/gui/rhi/qrhivulkan.cpp b/src/gui/rhi/qrhivulkan.cpp
index 9c39ab668a..851b225a56 100644
--- a/src/gui/rhi/qrhivulkan.cpp
+++ b/src/gui/rhi/qrhivulkan.cpp
@@ -2322,8 +2322,8 @@ void QRhiVulkan::beginPass(QRhiCommandBuffer *cb,
 
     QVkRenderTargetData *rtD = nullptr;
     switch (rt->resourceType()) {
-    case QRhiResource::RenderTarget:
-        rtD = &QRHI_RES(QVkReferenceRenderTarget, rt)->d;
+    case QRhiResource::SwapChainRenderTarget:
+        rtD = &QRHI_RES(QVkSwapChainRenderTarget, rt)->d;
         rtD->rp->lastActiveFrameSlot = currentFrameSlot;
         Q_ASSERT(currentSwapChain);
         currentSwapChain->imageRes[currentSwapChain->currentImageIndex].lastUse =
@@ -5122,8 +5122,8 @@ static inline QVkRenderTargetData *maybeRenderTargetData(QVkCommandBuffer *cbD)
     QVkRenderTargetData *rtD = nullptr;
     if (cbD->recordingPass == QVkCommandBuffer::RenderPass) {
         switch (cbD->currentTarget->resourceType()) {
-        case QRhiResource::RenderTarget:
-            rtD = &QRHI_RES(QVkReferenceRenderTarget, cbD->currentTarget)->d;
+        case QRhiResource::SwapChainRenderTarget:
+            rtD = &QRHI_RES(QVkSwapChainRenderTarget, cbD->currentTarget)->d;
             break;
         case QRhiResource::TextureRenderTarget:
             rtD = &QRHI_RES(QVkTextureRenderTarget, cbD->currentTarget)->d;
@@ -6432,32 +6432,32 @@ const QRhiNativeHandles *QVkRenderPassDescriptor::nativeHandles()
     return &nativeHandlesStruct;
 }
 
-QVkReferenceRenderTarget::QVkReferenceRenderTarget(QRhiImplementation *rhi)
-    : QRhiRenderTarget(rhi)
+QVkSwapChainRenderTarget::QVkSwapChainRenderTarget(QRhiImplementation *rhi, QRhiSwapChain *swapchain)
+    : QRhiSwapChainRenderTarget(rhi, swapchain)
 {
 }
 
-QVkReferenceRenderTarget::~QVkReferenceRenderTarget()
+QVkSwapChainRenderTarget::~QVkSwapChainRenderTarget()
 {
     destroy();
 }
 
-void QVkReferenceRenderTarget::destroy()
+void QVkSwapChainRenderTarget::destroy()
 {
     // nothing to do here
 }
 
-QSize QVkReferenceRenderTarget::pixelSize() const
+QSize QVkSwapChainRenderTarget::pixelSize() const
 {
     return d.pixelSize;
 }
 
-float QVkReferenceRenderTarget::devicePixelRatio() const
+float QVkSwapChainRenderTarget::devicePixelRatio() const
 {
     return d.dpr;
 }
 
-int QVkReferenceRenderTarget::sampleCount() const
+int QVkSwapChainRenderTarget::sampleCount() const
 {
     return d.sampleCount;
 }
@@ -7250,7 +7250,7 @@ const QRhiNativeHandles *QVkCommandBuffer::nativeHandles()
 
 QVkSwapChain::QVkSwapChain(QRhiImplementation *rhi)
     : QRhiSwapChain(rhi),
-      rtWrapper(rhi),
+      rtWrapper(rhi, this),
       cbWrapper(rhi)
 {
 }
diff --git a/src/gui/rhi/qrhivulkan_p_p.h b/src/gui/rhi/qrhivulkan_p_p.h
index f916d7d2b5..30cde199c8 100644
--- a/src/gui/rhi/qrhivulkan_p_p.h
+++ b/src/gui/rhi/qrhivulkan_p_p.h
@@ -219,10 +219,10 @@ struct QVkRenderTargetData
     static const int MAX_COLOR_ATTACHMENTS = 8;
 };
 
-struct QVkReferenceRenderTarget : public QRhiRenderTarget
+struct QVkSwapChainRenderTarget : public QRhiSwapChainRenderTarget
 {
-    QVkReferenceRenderTarget(QRhiImplementation *rhi);
-    ~QVkReferenceRenderTarget();
+    QVkSwapChainRenderTarget(QRhiImplementation *rhi, QRhiSwapChain *swapchain);
+    ~QVkSwapChainRenderTarget();
     void destroy() override;
 
     QSize pixelSize() const override;
@@ -625,7 +625,7 @@ struct QVkSwapChain : public QRhiSwapChain
     VkSampleCountFlagBits samples = VK_SAMPLE_COUNT_1_BIT;
     QVarLengthArray<VkPresentModeKHR, 8> supportedPresentationModes;
     VkDeviceMemory msaaImageMem = VK_NULL_HANDLE;
-    QVkReferenceRenderTarget rtWrapper;
+    QVkSwapChainRenderTarget rtWrapper;
     QVkCommandBuffer cbWrapper;
 
     struct ImageResources {