From 649e2e8b57b474945320f8ac8d2774ed7fd8ce63 Mon Sep 17 00:00:00 2001
From: assiduous <assiduous@diligentgraphics.com>
Date: Sun, 24 Nov 2024 17:59:42 -0800
Subject: [PATCH] HnMaterial: slightly reworked
 ApplyMaterialAttribsBufferOffset method

---
 Hydrogent/interface/HnMaterial.hpp | 13 ++++++-------
 Hydrogent/src/HnRenderPass.cpp     |  8 ++++----
 2 files changed, 10 insertions(+), 11 deletions(-)

diff --git a/Hydrogent/interface/HnMaterial.hpp b/Hydrogent/interface/HnMaterial.hpp
index f12c058c..b6923d26 100644
--- a/Hydrogent/interface/HnMaterial.hpp
+++ b/Hydrogent/interface/HnMaterial.hpp
@@ -91,11 +91,15 @@ class HnMaterial final : public pxr::HdMaterial
         m_PrimitiveAttribsVar->SetBufferOffset(PrimitiveAttribsOffset);
         return m_SRB;
     }
-    void ApplyMaterialAttribsBufferOffset() const
+    void ApplyMaterialAttribsBufferOffset(Uint32& CurrentOffset) const
     {
         VERIFY_EXPR(m_MaterialAttribsVar != nullptr);
         VERIFY_EXPR(m_PBRMaterialAttribsBufferOffset != ~0u);
-        m_MaterialAttribsVar->SetBufferOffset(m_PBRMaterialAttribsBufferOffset);
+        if (CurrentOffset != m_PBRMaterialAttribsBufferOffset)
+        {
+            m_MaterialAttribsVar->SetBufferOffset(m_PBRMaterialAttribsBufferOffset);
+            CurrentOffset = m_PBRMaterialAttribsBufferOffset;
+        }
     }
     void SetJointsBufferOffset(Uint32 Offset) const
     {
@@ -137,11 +141,6 @@ class HnMaterial final : public pxr::HdMaterial
 
     Uint32 GetPBRPrimitiveAttribsBufferRange() const { return m_PBRPrimitiveAttribsBufferRange; }
     Uint32 GetPBRMaterialAttribsSize() const { return m_PBRMaterialAttribsSize; }
-    Uint32 GetPBRMaterialAttribsBufferOffset() const
-    {
-        VERIFY_EXPR(m_PBRMaterialAttribsBufferOffset != ~0u);
-        return m_PBRMaterialAttribsBufferOffset;
-    }
 
 private:
     HnMaterial(pxr::SdfPath const& id);
diff --git a/Hydrogent/src/HnRenderPass.cpp b/Hydrogent/src/HnRenderPass.cpp
index 5ed3e31b..e00d896c 100644
--- a/Hydrogent/src/HnRenderPass.cpp
+++ b/Hydrogent/src/HnRenderPass.cpp
@@ -153,11 +153,11 @@ struct HnRenderPass::RenderState
             return;
         }
 
-        if (pNewSRB != this->pMaterialSRB || this->MaterialBufferOffset != Material.GetPBRMaterialAttribsBufferOffset())
+        if (pNewSRB != this->pMaterialSRB)
         {
-            Material.ApplyMaterialAttribsBufferOffset();
-            this->MaterialBufferOffset = Material.GetPBRMaterialAttribsBufferOffset();
+            this->MaterialBufferOffset = ~0u;
         }
+        Material.ApplyMaterialAttribsBufferOffset(this->MaterialBufferOffset);
 
         if (pNewSRB == this->pMaterialSRB)
             return;
@@ -226,7 +226,7 @@ struct HnRenderPass::RenderState
 
     IBuffer* pIndexBuffer = nullptr;
 
-    Uint32 MaterialBufferOffset = 0;
+    Uint32 MaterialBufferOffset = ~0u;
 
     Uint32                                         NumVertexBuffers = 0;
     std::array<IBuffer*, VERTEX_BUFFER_SLOT_COUNT> ppVertexBuffers  = {};