fix(extra-natives/rdr3): graphic natives flickering

Author: Ehbw

code/components/extra-natives-rdr3/src/GraphicsNatives.cpp

@@ -6,6 +6,8 @@
 #include "Hooking.Stubs.h"
 #include "GamePrimitives.h"
 #include "scrEngine.h"
+#include <nutsnbolts.h>
+#include <DrawCommands.h>
 
 enum ScriptImDrawType : uint32_t
 {
@@ -28,6 +30,9 @@ struct ScriptImRequest
 
 static constexpr int kMaxScriptImRequests = 1024;
 static std::vector<ScriptImRequest> g_scriptImRequests{};
+static std::vector<ScriptImRequest> g_scriptImRenderBuffer{};
+
+static std::atomic<bool> g_scriptImReady{false};
 
 static ScriptImRequest** g_scriptImBuffer;
 static uint16_t* g_scriptImEntriesCount;
@@ -43,20 +48,28 @@ static void RenderScriptIm()
 	// The game never uses this buffer itself, but it *may* be changed in the future updates.
 	// This code isn't ready for such a scenario, so might potentially require tweaks.
 	// Like if something allocate script im buffer before us, we would need to resize it
-	// and not just rewrite everything without custom stuff.
-
-	if (g_scriptImRequests.empty())
+	// and not just rewrite everything without custom stuff.
+
+	// Wait until the main thread is done for this frame before pushing new requests
+	if (g_scriptImReady.load(std::memory_order_acquire))
+	{
+		g_scriptImRenderBuffer.clear();
+		std::swap(g_scriptImRequests, g_scriptImRenderBuffer);
+		g_scriptImReady.store(false, std::memory_order_relaxed);
+	}
+
+	if (g_scriptImRenderBuffer.empty())
 	{
 		return;
 	}
 
-	*g_scriptImEntriesCount = g_scriptImRequests.size();
+	*g_scriptImEntriesCount = g_scriptImRenderBuffer.size();
 
 	// If the buffer isn't allocated, let's do it.
 	if (!*g_scriptImBuffer)
 	{
 		initScriptImBuffer();
-	}
+	}
 
 	// Failed to allocate? Bail out.
 	if (!*g_scriptImBuffer)
@@ -66,11 +79,9 @@ static void RenderScriptIm()
 	}
 
 	// Move stuff from our temp vector to the in-game buffer.
-	std::move(g_scriptImRequests.begin(), g_scriptImRequests.end(), *g_scriptImBuffer);
+	std::copy(g_scriptImRenderBuffer.begin(), g_scriptImRenderBuffer.end(), *g_scriptImBuffer);
 
 	g_origRenderScriptIm();
-
-	g_scriptImRequests.clear();
 	*g_scriptImEntriesCount = 0;
 }
 
@@ -90,8 +101,8 @@ struct DrawOriginStore
 
 static bool (*isGamePaused)();
 
-static int* g_frameDrawIndex1;
-static int* g_frameDrawIndex2;
+static int* g_renderBufferIndex;
+static int* g_updateBufferIndex;
 static DrawOriginStore* g_drawOriginStore;
 static uint32_t* g_scriptDrawOriginIndex;
 
@@ -124,8 +135,8 @@ static HookFunction hookFunction([]()
 	{
 		auto location = hook::get_pattern<char>("48 69 D0 10 04 00 00 48 8D 05 ? ? ? ? 48 03");
 
-		g_frameDrawIndex1 = hook::get_address<int*>(location - 20);
-		g_frameDrawIndex2 = hook::get_address<int*>(location - 7);
+		g_renderBufferIndex = hook::get_address<int*>(location - 20);
+		g_updateBufferIndex = hook::get_address<int*>(location - 7);
 		g_drawOriginStore = hook::get_address<DrawOriginStore*>(location + 10);
 
 		hook::set_call(&isGamePaused, location - 27);
@@ -153,13 +164,22 @@ static HookFunction hookFunction([]()
 
 		g_screenWidth = hook::get_address<int*>(location + 2);
 		g_screenHeight = hook::get_address<int*>(location + 8);
-	}
+	}
+
+	OnMainGameFrame.Connect([]()
+	{
+		g_scriptImRequests.clear();
+		g_scriptImReady.store(false, std::memory_order_relaxed);
+	});
+
+	OnPostFrontendRender.Connect([]()
+	{
+		g_scriptImReady.store(true, std::memory_order_release);
+	});
 
 	fx::ScriptEngine::RegisterNativeHandler("SET_DRAW_ORIGIN", [](fx::ScriptContext& context)
 	{
-		auto drawIndex = *(isGamePaused() ? g_frameDrawIndex2 : g_frameDrawIndex1);
-
-		auto& store = g_drawOriginStore[drawIndex];
+		auto& store = g_drawOriginStore[*g_renderBufferIndex];
 		const auto index = store.m_count;
 
 		if (index >= 32)