From 744bfe7800707d7ca2d84224677b9c7781b3356e Mon Sep 17 00:00:00 2001
From: sukibaby <163092272+sukibaby@users.noreply.github.com>
Date: Sat, 12 Apr 2025 22:55:37 -0700
Subject: [PATCH] Global function CallEveryNFrames

Call a function every `n` frames.
---
 src/GameLoop.cpp             |  7 +------
 src/ScreenMapControllers.cpp | 14 ++++++--------
 src/global.h                 | 13 +++++++++++++
 3 files changed, 20 insertions(+), 14 deletions(-)

diff --git a/src/GameLoop.cpp b/src/GameLoop.cpp
index d288c6d065..79b79a5c23 100644
--- a/src/GameLoop.cpp
+++ b/src/GameLoop.cpp
@@ -326,12 +326,7 @@ void GameLoop::RunGameLoop()
 
 		UpdateAllButDraw(false);
 		
-		// Check input devices every 255 frames (uint8_t can hold 0-255).
-		static uint8_t i_CheckInputDevices = 0;
-		if (++i_CheckInputDevices == 0)
-		{
-			CheckInputDevices();
-		}
+		CallEveryNFrames(500, CheckInputDevices);
 		
 		SCREENMAN->Draw();
 	}
diff --git a/src/ScreenMapControllers.cpp b/src/ScreenMapControllers.cpp
index 6f1f9d7948..6f1da38155 100644
--- a/src/ScreenMapControllers.cpp
+++ b/src/ScreenMapControllers.cpp
@@ -278,16 +278,14 @@ void ScreenMapControllers::Update( float fDeltaTime )
 		}
 	}
 
-	//
-	// Update devices text every 120ish frames
+	// Update devices text every 500 frames.
 	// This is NOT updating the actual text shown!
-	// it is updating the names of the devices here.
-	//
-	static uint8_t e= 0;
-	++e;
-	if (e == 0 || e == 127) {
+	// This is polling every active driver for an updated
+	// list of button to device mappings.
+	CallEveryNFrames(500, [this]() {
+		// If we don't pass the `this` pointer, the lambda can't get access to the ScreenMapControllers instance.
 		m_textDevices.SetText(INPUTMAN->GetDisplayDevicesString());
-	}
+		});
 
 	if( !m_WaitingForPress.IsZero() && m_DeviceIToMap.IsValid() ) // we're going to map an input
 	{
diff --git a/src/global.h b/src/global.h
index 2557c9fe3c..08433918b1 100644
--- a/src/global.h
+++ b/src/global.h
@@ -108,6 +108,19 @@ typedef StdString::CStdString RString;
 
 #include "RageException.h"
 
+// Call a function every `n` frames.
+// Each call site will get its own counter.
+#include <utility>
+template <typename Func, typename... Args>
+void CallEveryNFrames(int n, Func&& f, Args&&... args) {
+	static int counter = 0;
+	++counter;
+	if (counter == n) {
+		counter = 0;
+		std::forward<Func>(f)(std::forward<Args>(args)...);
+	}
+}
+
 /* Don't include our own headers here, since they tend to change often. */
 
 #endif