GENERATE_NORMALS generates completely useless normals

[Einheit-101]

Describe the bug

Recently i tried this HLSL value and the result is bad. I dont know if this can even be fixed but in its current state GENERATE_NORMALS is literally useless:

https://imgur.com/a/CsVJDTL

Steps to reproduce

1. Export a model with vertex prelight and vertex color (Doing so will export the model without vertex normals due to DFF limitation)
2. Replace any object
3. Apply a dynamic lighting shader to that object that uses normals to calculate the light, it will be completely screwed

Version

Multi Theft Auto v1.5.9-release-21166

Additional context

No response

Relevant log output

No response

Security Policy

• I have read and understood the Security Policy and this issue is not security related.

[borsuczyna]

It doesn't generate any normals, takes them from model, if they are not present normals will be 0,0,0

[Einheit-101]

How is it possible that there are no normals? The faces must face in a direction. It should take these values. What it currently does looks like fully random.

[borsuczyna]

mtasa-blue/Client/core/CAdditionalVertexStreamManager.cpp

Lines 105 to 128 in 16769b8

	bool CAdditionalVertexStreamManager::MaybeSetAdditionalVertexStream(D3DPRIMITIVETYPE PrimitiveType, INT BaseVertexIndex, UINT MinVertexIndex, UINT NumVertices,
	UINT startIndex, UINT primCount)
	{
	// Cache info
	SCurrentStateInfo state;
	// Save call arguments
	state.args.PrimitiveType = PrimitiveType;
	state.args.BaseVertexIndex = BaseVertexIndex;
	state.args.MinVertexIndex = MinVertexIndex;
	state.args.NumVertices = NumVertices;
	state.args.startIndex = startIndex;
	state.args.primCount = primCount;
	// Cache info about state streams etc
	UpdateCurrentStateInfo(state);
	// For now, this only works if the original has 3 decl elements (0:D, 1:P, 1:T) and stream 1 has a stride of 20
	if (!CheckCanDoThis(state))
	return false;
	SetAdditionalVertexStream(state);
	return true;
	}

CheckCanDoThis looks like reason of this

[Einheit-101]

It seems that the normal handling needs improvement and this solution has been made transitional only as long as there is nothing better available

[tederis]

It doesn't generate any normals, takes them from model, if they are not present normals will be 0,0,0

That is not true. See CAdditionalVertexStreamManager::UpdateAdditionalStreamContent