From f1ad9a7e9698eee55788485e0990cc8fadceeb54 Mon Sep 17 00:00:00 2001
From: Chris Adams <chris.adams@daktronics.com>
Date: Tue, 4 Nov 2025 14:09:51 -0500
Subject: [PATCH 1/2] added in vertex start positions to address gltf file with
 mixed indicies/no indicies primitives

---
 AssetLoader/interface/GLTFBuilder.hpp | 1 +
 AssetLoader/interface/GLTFLoader.hpp  | 3 +++
 2 files changed, 4 insertions(+)

diff --git a/AssetLoader/interface/GLTFBuilder.hpp b/AssetLoader/interface/GLTFBuilder.hpp
index 26444769..8c98d3d3 100644
--- a/AssetLoader/interface/GLTFBuilder.hpp
+++ b/AssetLoader/interface/GLTFBuilder.hpp
@@ -461,6 +461,7 @@ Mesh* ModelBuilder::LoadMesh(const GltfModelType& GltfModel,
             IndexStart,
             IndexCount,
             VertexCount,
+            VertexStart,
             static_cast<Uint32>(MaterialId),
             PosMin,
             PosMax //
diff --git a/AssetLoader/interface/GLTFLoader.hpp b/AssetLoader/interface/GLTFLoader.hpp
index 02699abe..41e60b5f 100644
--- a/AssetLoader/interface/GLTFLoader.hpp
+++ b/AssetLoader/interface/GLTFLoader.hpp
@@ -410,6 +410,7 @@ struct Primitive
     const Uint32 FirstIndex;
     const Uint32 IndexCount;
     const Uint32 VertexCount;
+    const Uint32 VertexStart;
     const Uint32 MaterialId;
 
     const BoundBox BB;
@@ -417,12 +418,14 @@ struct Primitive
     Primitive(Uint32        _FirstIndex,
               Uint32        _IndexCount,
               Uint32        _VertexCount,
+              Uint32        _VertexStart,
               Uint32        _MaterialId,
               const float3& _BBMin,
               const float3& _BBMax) :
         FirstIndex{_FirstIndex},
         IndexCount{_IndexCount},
         VertexCount{_VertexCount},
+        VertexStart{_VertexStart},
         MaterialId{_MaterialId},
         BB{_BBMin, _BBMax}
     {

From 2a156a1f38f5a70c156522d43a3997b04a8284be Mon Sep 17 00:00:00 2001
From: Chris Adams <chris.adams@daktronics.com>
Date: Thu, 6 Nov 2025 11:26:36 -0500
Subject: [PATCH 2/2] pr updates

---
 AssetLoader/interface/GLTFBuilder.hpp | 2 ++
 AssetLoader/interface/GLTFLoader.hpp  | 6 +++---
 2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/AssetLoader/interface/GLTFBuilder.hpp b/AssetLoader/interface/GLTFBuilder.hpp
index 8c98d3d3..b52671e4 100644
--- a/AssetLoader/interface/GLTFBuilder.hpp
+++ b/AssetLoader/interface/GLTFBuilder.hpp
@@ -444,6 +444,8 @@ Mesh* ModelBuilder::LoadMesh(const GltfModelType& GltfModel,
         if (GltfPrimitive.GetIndicesId() >= 0)
         {
             IndexCount = ConvertIndexData(GltfModel, GltfPrimitive.GetIndicesId(), VertexStart);
+            // For indexed primitives, the vertex offset is baked into the indices,
+            VertexStart = 0;
         }
 
         int MaterialId = GltfPrimitive.GetMaterialId();
diff --git a/AssetLoader/interface/GLTFLoader.hpp b/AssetLoader/interface/GLTFLoader.hpp
index 41e60b5f..ecdeff81 100644
--- a/AssetLoader/interface/GLTFLoader.hpp
+++ b/AssetLoader/interface/GLTFLoader.hpp
@@ -410,7 +410,7 @@ struct Primitive
     const Uint32 FirstIndex;
     const Uint32 IndexCount;
     const Uint32 VertexCount;
-    const Uint32 VertexStart;
+    const Uint32 FirstVertex;
     const Uint32 MaterialId;
 
     const BoundBox BB;
@@ -418,14 +418,14 @@ struct Primitive
     Primitive(Uint32        _FirstIndex,
               Uint32        _IndexCount,
               Uint32        _VertexCount,
-              Uint32        _VertexStart,
+              Uint32        _FirstVertex,
               Uint32        _MaterialId,
               const float3& _BBMin,
               const float3& _BBMax) :
         FirstIndex{_FirstIndex},
         IndexCount{_IndexCount},
         VertexCount{_VertexCount},
-        VertexStart{_VertexStart},
+        FirstVertex{_FirstVertex},
         MaterialId{_MaterialId},
         BB{_BBMin, _BBMax}
     {