tessellation fix when using provoking index buffer

WickedEngine/shaders/objectHF.hlsli

@@ -80,6 +80,7 @@ PUSHCONSTANT(push, ObjectPushConstants);
 //#define OBJECTSHADER_USE_INSTANCEINDEX			- shader will use instance ID
 //#define OBJECTSHADER_USE_CAMERAINDEX				- shader will use camera ID
 //#define OBJECTSHADER_USE_COMMON					- shader will use atlas, ambient occlusion, wetmap
+//#define OBJECTSHADER_USE_PROVOKING_INDEX_BUFFER	- shader will load vertex ID through provoking index buffer reordering
 
 
 #ifdef OBJECTSHADER_LAYOUT_SHADOW
@@ -121,25 +122,23 @@ struct VertexInput
 {
 	uint vertexID : SV_VertexID;
 	uint instanceID : SV_InstanceID;
-
+	
+#ifdef OBJECTSHADER_USE_PROVOKING_INDEX_BUFFER
 	uint GetPrimitiveID()
 	{
-#if defined(PREPASS) && !defined(OBJECTSHADER_COMPILE_MS)
 		// For prepass the meshopt_generateProvokingIndexBuffer is used to emulate SV_PrimitiveID via provoking vertex
 		return vertexID;
-#else
-		return 0;
-#endif // defined(PREPASS) && !defined(OBJECTSHADER_COMPILE_MS)
 	}
+#endif // OBJECTSHADER_USE_PROVOKING_INDEX_BUFFER
 
 	uint GetVertexID()
 	{
-#if defined(PREPASS) && !defined(OBJECTSHADER_COMPILE_MS)
+#ifdef OBJECTSHADER_USE_PROVOKING_INDEX_BUFFER
 		// For prepass the meshopt_generateProvokingIndexBuffer is used to emulate SV_PrimitiveID via provoking vertex
 		return bindless_buffers_uint[descriptor_index(GetMesh().ib_reorder)][vertexID];
 #else
 		return vertexID;
-#endif // defined(PREPASS) && !defined(OBJECTSHADER_COMPILE_MS)
+#endif // OBJECTSHADER_USE_PROVOKING_INDEX_BUFFER
 	}
 
 	float4 GetPositionWind()
@@ -410,9 +409,9 @@ PixelInput vertex_to_pixel_export(VertexInput input)
 	ShaderCamera camera = GetCamera();
 #endif // OBJECTSHADER_USE_CAMERAINDEX
 	
-#if defined(PREPASS) && !defined(OBJECTSHADER_COMPILE_MS)
+#if defined(PREPASS) && defined(OBJECTSHADER_USE_PROVOKING_INDEX_BUFFER)
 	Out.primitiveID = input.GetPrimitiveID();
-#endif // defined(PREPASS) && !defined(OBJECTSHADER_COMPILE_MS)
+#endif // defined(PREPASS) && defined(OBJECTSHADER_USE_PROVOKING_INDEX_BUFFER)
 
 #ifndef OBJECTSHADER_USE_NOCAMERA
 	Out.pos = mul(camera.view_projection, Out.pos);

WickedEngine/shaders/objectVS_common_tessellation.hlsl

@@ -1,4 +1,5 @@
 #define OBJECTSHADER_COMPILE_VS
 #define OBJECTSHADER_LAYOUT_COMMON
 #define OBJECTSHADER_USE_NOCAMERA
+#define OBJECTSHADER_USE_PROVOKING_INDEX_BUFFER
 #include "objectHF.hlsli"

WickedEngine/shaders/objectVS_prepass.hlsl

@@ -1,3 +1,4 @@
 #define OBJECTSHADER_COMPILE_VS
 #define OBJECTSHADER_LAYOUT_PREPASS
+#define OBJECTSHADER_USE_PROVOKING_INDEX_BUFFER
 #include "objectHF.hlsli"

WickedEngine/shaders/objectVS_prepass_alphatest.hlsl

@@ -1,3 +1,4 @@
 #define OBJECTSHADER_COMPILE_VS
 #define OBJECTSHADER_LAYOUT_PREPASS_TEX
+#define OBJECTSHADER_USE_PROVOKING_INDEX_BUFFER
 #include "objectHF.hlsli"

WickedEngine/shaders/objectVS_prepass_alphatest_tessellation.hlsl

@@ -2,5 +2,6 @@
 #define OBJECTSHADER_LAYOUT_PREPASS_TEX
 #define OBJECTSHADER_USE_NOCAMERA
 #define OBJECTSHADER_USE_NORMAL
+#define OBJECTSHADER_USE_PROVOKING_INDEX_BUFFER
 #include "objectHF.hlsli"
 

WickedEngine/shaders/objectVS_prepass_tessellation.hlsl

@@ -2,4 +2,5 @@
 #define OBJECTSHADER_LAYOUT_PREPASS_TEX
 #define OBJECTSHADER_USE_NOCAMERA
 #define OBJECTSHADER_USE_NORMAL
+#define OBJECTSHADER_USE_PROVOKING_INDEX_BUFFER
 #include "objectHF.hlsli"

WickedEngine/wiRenderer.cpp

@@ -3169,7 +3169,12 @@ void RenderMeshes(
 		const float tessF = mesh.GetTessellationFactor();
 		const bool tessellatorRequested = tessF > 0 && tessellation;
 		const bool meshShaderRequested = !tessellatorRequested && mesh_shader && mesh.vb_clu.IsValid();
-		const bool provokingIBRequired = renderPass == RENDERPASS_PREPASS || renderPass == RENDERPASS_PREPASS_DEPTHONLY; // Note: depthonly doesn't need primitiveID, but for now I don't created specialized shader for it without primitiveID (TODO measure perf, additional shaders overhead)
+
+		// Notes on provoking index buffer:
+		//	Normally it's used for primitiveID generation, so it would be only used in PREPASS
+		//	PREPASS_DEPTHONLY doesn't use separate shader variants, so it will also use provoking index buffer
+		//	tessellation requires it to match same primitive order between prepass and color pass to have exact same tessellation
+		const bool provokingIBRequired = renderPass == RENDERPASS_PREPASS || renderPass == RENDERPASS_PREPASS_DEPTHONLY || tessellatorRequested;
 
 		if (forwardLightmaskRequest)
 		{

WickedEngine/wiVersion.cpp

@@ -9,7 +9,7 @@ namespace wi::version
 	// minor features, major updates, breaking compatibility changes
 	const int minor = 71;
 	// minor bug fixes, alterations, refactors, updates
-	const int revision = 835;
+	const int revision = 836;
 
 	const std::string version_string = std::to_string(major) + "." + std::to_string(minor) + "." + std::to_string(revision);