Implemented unified render pass attachment state updates within subpasses and after the render pass ends

3 files changed, 65 insertions, 29 deletions

diff --git a/Graphics/GraphicsEngine/include/DeviceContextBase.hpp b/Graphics/GraphicsEngine/include/DeviceContextBase.hpp
index a340bbd2..e5d9b90e 100644
--- a/Graphics/GraphicsEngine/include/DeviceContextBase.hpp
+++ b/Graphics/GraphicsEngine/include/DeviceContextBase.hpp
@@ -126,7 +126,7 @@ public:
 
     virtual void DILIGENT_CALL_TYPE NextSubpass() override = 0;
 
-    virtual void DILIGENT_CALL_TYPE EndRenderPass(bool UpdateResourceStates) override = 0;
+    virtual void DILIGENT_CALL_TYPE EndRenderPass() override = 0;
 
     /// Base implementation of IDeviceContext::UpdateBuffer(); validates input parameters.
     virtual void DILIGENT_CALL_TYPE UpdateBuffer(IBuffer*                       pBuffer,
@@ -228,6 +228,9 @@ protected:
     /// Checks if the texture is currently bound as depth-stencil buffer.
     bool CheckIfBoundAsDepthStencil(TextureImplType* pTexture);
 
+    /// Updates the states of render pass attachments to match states within the gievn subpass
+    void UpdateAttachmentStates(Uint32 SubpassIndex);
+
     bool ClearDepthStencil(ITextureView* pView);
 
     bool ClearRenderTarget(ITextureView* pView);
@@ -329,6 +332,9 @@ protected:
     /// Current subpass index.
     Uint32 m_SubpassIndex = 0;
 
+    /// Render pass attachments transition mode.
+    RESOURCE_STATE_TRANSITION_MODE m_RenderPassAttachmentsTransitionMode = RESOURCE_STATE_TRANSITION_MODE_NONE;
+
     const bool m_bIsDeferred = false;
 
 #ifdef DILIGENT_DEBUG
@@ -970,9 +976,11 @@ inline void DeviceContextBase<BaseInterface, ImplementationTraits>::BeginRenderP
         }
     }
 
-    m_pActiveRenderPass = pNewRenderPass;
-    m_pBoundFramebuffer = pNewFramebuffer;
-    m_SubpassIndex      = 0;
+    m_pActiveRenderPass                   = pNewRenderPass;
+    m_pBoundFramebuffer                   = pNewFramebuffer;
+    m_SubpassIndex                        = 0;
+    m_RenderPassAttachmentsTransitionMode = Attribs.StateTransitionMode;
+    UpdateAttachmentStates(m_SubpassIndex);
     SetSubpassRenderTargets();
 }
 
@@ -982,36 +990,54 @@ inline void DeviceContextBase<BaseInterface, ImplementationTraits>::NextSubpass(
     VERIFY(m_pActiveRenderPass != nullptr, "There is no active render pass");
     VERIFY(m_SubpassIndex + 1 < m_pActiveRenderPass->GetDesc().SubpassCount, "The render pass has reached the final subpass already");
     ++m_SubpassIndex;
+    UpdateAttachmentStates(m_SubpassIndex);
     SetSubpassRenderTargets();
 }
 
 template <typename BaseInterface, typename ImplementationTraits>
-inline void DeviceContextBase<BaseInterface, ImplementationTraits>::EndRenderPass(bool UpdateResourceStates)
+inline void DeviceContextBase<BaseInterface, ImplementationTraits>::UpdateAttachmentStates(Uint32 SubpassIndex)
 {
-    VERIFY(m_pActiveRenderPass != nullptr, "There is no active render pass");
-    VERIFY(m_pBoundFramebuffer != nullptr, "There is no active framebuffer");
-    VERIFY(m_pActiveRenderPass->GetDesc().SubpassCount == m_SubpassIndex + 1,
-           "Ending render pass at subpass ", m_SubpassIndex, " before reaching the final subpass");
+    if (m_RenderPassAttachmentsTransitionMode != RESOURCE_STATE_TRANSITION_MODE_TRANSITION)
+        return;
+
+    VERIFY_EXPR(m_pActiveRenderPass != nullptr);
+    VERIFY_EXPR(m_pBoundFramebuffer != nullptr);
 
-    if (UpdateResourceStates)
+    const auto& RPDesc = m_pActiveRenderPass->GetDesc();
+    const auto& FBDesc = m_pBoundFramebuffer->GetDesc();
+    VERIFY(FBDesc.AttachmentCount == RPDesc.AttachmentCount,
+           "Framebuffer attachment count (", FBDesc.AttachmentCount, ") is not consistent with the render pass attachment count (", RPDesc.AttachmentCount, ")");
+    VERIFY_EXPR(SubpassIndex <= RPDesc.SubpassCount);
+    for (Uint32 i = 0; i < RPDesc.AttachmentCount; ++i)
     {
-        const auto& RPDesc = m_pActiveRenderPass->GetDesc();
-        const auto& FBDesc = m_pBoundFramebuffer->GetDesc();
-        VERIFY(FBDesc.AttachmentCount >= RPDesc.AttachmentCount,
-               "Framebuffer attachment count (", FBDesc.AttachmentCount, ") is smaller than the render pass attachment count (", RPDesc.AttachmentCount, ")");
-        for (Uint32 i = 0; i < RPDesc.AttachmentCount; ++i)
+        if (auto* pView = FBDesc.ppAttachments[i])
         {
-            if (auto* pView = FBDesc.ppAttachments[i])
+            auto* pTex = ValidatedCast<TextureImplType>(pView->GetTexture());
+            if (pTex->IsInKnownState())
             {
-                auto* pTex = ValidatedCast<TextureImplType>(pView->GetTexture());
-                if (pTex->IsInKnownState())
-                    pTex->SetState(RPDesc.pAttachments[i].FinalState);
+                auto CurrState = SubpassIndex < RPDesc.SubpassCount ?
+                    m_pActiveRenderPass->GetAttachmentState(SubpassIndex, i) :
+                    RPDesc.pAttachments[i].FinalState;
+                pTex->SetState(CurrState);
             }
         }
     }
+}
+
+template <typename BaseInterface, typename ImplementationTraits>
+inline void DeviceContextBase<BaseInterface, ImplementationTraits>::EndRenderPass()
+{
+    VERIFY(m_pActiveRenderPass != nullptr, "There is no active render pass");
+    VERIFY(m_pBoundFramebuffer != nullptr, "There is no active framebuffer");
+    VERIFY(m_pActiveRenderPass->GetDesc().SubpassCount == m_SubpassIndex + 1,
+           "Ending render pass at subpass ", m_SubpassIndex, " before reaching the final subpass");
+
+    UpdateAttachmentStates(m_SubpassIndex + 1);
+
     m_pActiveRenderPass.Release();
     m_pBoundFramebuffer.Release();
-    m_SubpassIndex = 0;
+    m_SubpassIndex                        = 0;
+    m_RenderPassAttachmentsTransitionMode = RESOURCE_STATE_TRANSITION_MODE_NONE;
     ResetRenderTargets();
 }
 
diff --git a/Graphics/GraphicsEngine/include/TextureBase.hpp b/Graphics/GraphicsEngine/include/TextureBase.hpp
index fd0256b6..1805f7d3 100644
--- a/Graphics/GraphicsEngine/include/TextureBase.hpp
+++ b/Graphics/GraphicsEngine/include/TextureBase.hpp
@@ -184,6 +184,12 @@ public:
         return (this->m_State & State) == State;
     }
 
+    bool CheckAnyState(RESOURCE_STATE States) const
+    {
+        VERIFY(IsInKnownState(), "Texture state is unknown");
+        return (this->m_State & States) != 0;
+    }
+
     /// Implementation of ITexture::GetDefaultView().
     virtual ITextureView* DILIGENT_CALL_TYPE GetDefaultView(TEXTURE_VIEW_TYPE ViewType) override
     {
diff --git a/Graphics/GraphicsEngine/interface/DeviceContext.h b/Graphics/GraphicsEngine/interface/DeviceContext.h
index 3445a8d6..eb77ba8e 100644
--- a/Graphics/GraphicsEngine/interface/DeviceContext.h
+++ b/Graphics/GraphicsEngine/interface/DeviceContext.h
@@ -633,7 +633,18 @@ struct BeginRenderPassAttribs
     /// Other elements of pClearValues are ignored.
     OptimizedClearValue* pClearValues   DEFAULT_INITIALIZER(nullptr);
 
-    /// Framebuffer attachments state transition mode.
+    /// Framebuffer attachments state transition mode before the render pass begins.
+
+    /// This parameter also indicates how attachment states should be handled when
+    /// transitioning between subpasses as well as after the render pass ends.
+    /// When RESOURCE_STATE_TRANSITION_MODE_TRANSITION is used, attachment states will be
+    /// updated so that they match the state in the current subpass as well as the final states
+    /// specified by the render pass when the pass ends.
+    /// Note that resources are always transitioned. The flag only indicates if the internal
+    /// state variables should be updated.
+    /// When RESOURCE_STATE_TRANSITION_MODE_NONE or RESOURCE_STATE_TRANSITION_MODE_VERIFY is used,
+    /// internal state variables are not updated and it is the application responsibility to set them
+    /// manually to match the actual states.
     RESOURCE_STATE_TRANSITION_MODE StateTransitionMode DEFAULT_INITIALIZER(RESOURCE_STATE_TRANSITION_MODE_NONE);
 };
 typedef struct BeginRenderPassAttribs BeginRenderPassAttribs;
@@ -905,14 +916,7 @@ DILIGENT_BEGIN_INTERFACE(IDeviceContext, IObject)
 
 
     /// Ends current render pass.
-
-    /// \param [in] UpdateResourceStates - Indicates whether to update resource states so that they match
-    ///                                    the final states specified by the render pass attachments.
-    ///                                    Note that resources are always transitioned to the final states.
-    ///                                    The flag only indicates if the internal state variables should be
-    ///                                    updated to match the actual final states.
-    VIRTUAL void METHOD(EndRenderPass)(THIS_
-                                       bool UpdateResourceStates) PURE;
+    VIRTUAL void METHOD(EndRenderPass)(THIS) PURE;
 
 
     /// Executes a draw command.