latencyflex.cpp

#include "core/convar/convar.h"

ConVar* Cvar_r_latencyflex;

void (*m_winelfx_WaitAndBeginFrame)();

void(__fastcall* o_pOnRenderStart)() = nullptr;
void __fastcall h_OnRenderStart()
{
	if (Cvar_r_latencyflex->GetBool() && m_winelfx_WaitAndBeginFrame)
		m_winelfx_WaitAndBeginFrame();

	o_pOnRenderStart();
}

ON_DLL_LOAD_CLIENT_RELIESON("client.dll", LatencyFlex, ConVar, (CModule module))
{
	// Connect to the LatencyFleX service
	// LatencyFleX is an open source vendor agnostic replacement for Nvidia Reflex input latency reduction technology.
	// https://ishitatsuyuki.github.io/post/latencyflex/
	HMODULE pLfxModule;

	if ((pLfxModule = LoadLibraryA("latencyflex_layer.dll")))
		m_winelfx_WaitAndBeginFrame =
			reinterpret_cast<void (*)()>(reinterpret_cast<void*>(GetProcAddress(pLfxModule, "lfx_WaitAndBeginFrame")));
	else if ((pLfxModule = LoadLibraryA("latencyflex_wine.dll")))
		m_winelfx_WaitAndBeginFrame =
			reinterpret_cast<void (*)()>(reinterpret_cast<void*>(GetProcAddress(pLfxModule, "winelfx_WaitAndBeginFrame")));
	else
	{
		spdlog::info("Unable to load LatencyFleX library, LatencyFleX disabled.");
		return;
	}

	o_pOnRenderStart = module.Offset(0x1952C0).RCast<decltype(o_pOnRenderStart)>();
	HookAttach(&(PVOID&)o_pOnRenderStart, (PVOID)h_OnRenderStart);

	spdlog::info("LatencyFleX initialized.");
	Cvar_r_latencyflex = new ConVar("r_latencyflex", "1", FCVAR_ARCHIVE, "Whether or not to use LatencyFleX input latency reduction.");
}