NRD: "frameIndex" validation moved from NRD to Integration (since there is no "frame" idiom in NRD)

Author: dzhdanNV

Include/NRDSettings.h

@@ -167,7 +167,7 @@ namespace nrd
         uint32_t rectOrigin[2] = {};
 
         // A consecutively growing number. Valid usage:
-        // - must be incremented by 1 each frame
+        // - must be incremented by 1 on each frame (not by 1 on each "SetCommonSettings" call)
         // - sequence can be restarted after passing "AccumulationMode != CONTINUE"
         // - must be in sync with "CheckerboardMode" (if not OFF)
         uint32_t frameIndex = 0;

Integration/NRDIntegration.h

@@ -148,6 +148,7 @@ class Integration
     uint32_t m_ConstantBufferOffset = 0;
     uint32_t m_DescriptorPoolIndex = 0;
     uint32_t m_FrameIndex = uint32_t(-1); // 0 needed after 1st "NewFrame"
+    uint32_t m_PrevFrameIndexFromSettings = 0;
     uint8_t m_BufferedFramesNum = 0;
     char m_Name[32] = {};
     bool m_ReloadShaders = false;

Integration/NRDIntegration.hpp

@@ -478,6 +478,7 @@ void Integration::NewFrame()
     }
 
     m_FrameIndex++;
+    m_PrevFrameIndexFromSettings++;
 }
 
 bool Integration::SetCommonSettings(const CommonSettings& commonSettings)
@@ -487,6 +488,11 @@ bool Integration::SetCommonSettings(const CommonSettings& commonSettings)
     Result result = nrd::SetCommonSettings(*m_Instance, commonSettings);
     NRD_INTEGRATION_ASSERT(result == Result::SUCCESS, "SetCommonSettings(): failed!");
 
+    if (m_FrameIndex == 0 || commonSettings.accumulationMode != AccumulationMode::CONTINUE)
+        m_PrevFrameIndexFromSettings = commonSettings.frameIndex;
+    else
+        NRD_INTEGRATION_ASSERT(m_PrevFrameIndexFromSettings == commonSettings.frameIndex, "'frameIndex' must be incremented by 1 on each frame");
+
     return result == Result::SUCCESS;
 }
 

Source/InstanceImpl.cpp

@@ -302,9 +302,6 @@ nrd::Result nrd::InstanceImpl::SetCommonSettings(const CommonSettings& commonSet
     isValid &= commonSettings.disocclusionThresholdAlternate > 0.0f;
     assert("'disocclusionThresholdAlternate' must be > 0" && isValid);
 
-    isValid &= commonSettings.accumulationMode != AccumulationMode::CONTINUE || commonSettings.frameIndex == m_CommonSettings.frameIndex + 1 || m_IsFirstUse;
-    assert("'frameIndex' must be a consecutively growing number" && isValid);
-
     isValid &= commonSettings.strandMaterialID != 0.0f || GetLibraryDesc().normalEncoding == NormalEncoding::R10_G10_B10_A2_UNORM;
     assert("'strandMaterialID' can't be 0 if material ID is not supported by encoding" && isValid);