From 9b0bd3c03f76261820ab7619f36cd2c2ae761ebd Mon Sep 17 00:00:00 2001
From: serge_shubin <serge@generalarcade.com>
Date: Sat, 21 Mar 2026 20:51:28 +0800
Subject: [PATCH] Input sticky buttons fixed

---
 code/win32/win_input.c | 70 +++++++++++++++---------------------------
 1 file changed, 25 insertions(+), 45 deletions(-)

diff --git a/code/win32/win_input.c b/code/win32/win_input.c
index d7990dd..93d1f1b 100644
--- a/code/win32/win_input.c
+++ b/code/win32/win_input.c
@@ -343,13 +343,20 @@ void IN_DIMouse( int *mx, int *my ) {
 	DIMOUSESTATE2		state;
 	DWORD				dwElements;
 	HRESULT				hr;
-	int					value;
+	int					i, value;
+	static BYTE			oldButtons[8];
+
+	static const int buttonKeys[5] = {
+		K_MOUSE1, K_MOUSE2, K_MOUSE3, K_MOUSE4, K_MOUSE5
+	};
 
 	if ( !g_pMouse ) {
 		return;
 	}
 
-	// fetch new events
+	// flush the buffered data — we only use it for wheel events.
+	// buttons are handled via immediate state below to avoid
+	// stuck keys from buffer overflow.
 	for (;;)
 	{
 		dwElements = 1;
@@ -361,51 +368,11 @@ void IN_DIMouse( int *mx, int *my ) {
 			return;
 		}
 
-		/* Unable to read data or no data available */
-		if ( FAILED(hr) ) {
-			break;
-		}
-
-		if ( dwElements == 0 ) {
+		if ( FAILED(hr) || dwElements == 0 ) {
 			break;
 		}
 
 		switch (od.dwOfs) {
-		case DIMOFS_BUTTON0:
-			if (od.dwData & 0x80)
-				Sys_QueEvent( od.dwTimeStamp, SE_KEY, K_MOUSE1, qtrue, 0, NULL );
-			else
-				Sys_QueEvent( od.dwTimeStamp, SE_KEY, K_MOUSE1, qfalse, 0, NULL );
-			break;
-
-		case DIMOFS_BUTTON1:
-			if (od.dwData & 0x80)
-				Sys_QueEvent( od.dwTimeStamp, SE_KEY, K_MOUSE2, qtrue, 0, NULL );
-			else
-				Sys_QueEvent( od.dwTimeStamp, SE_KEY, K_MOUSE2, qfalse, 0, NULL );
-			break;
-
-		case DIMOFS_BUTTON2:
-			if (od.dwData & 0x80)
-				Sys_QueEvent( od.dwTimeStamp, SE_KEY, K_MOUSE3, qtrue, 0, NULL );
-			else
-				Sys_QueEvent( od.dwTimeStamp, SE_KEY, K_MOUSE3, qfalse, 0, NULL );
-			break;
-
-		case DIMOFS_BUTTON3:
-			if (od.dwData & 0x80)
-				Sys_QueEvent( od.dwTimeStamp, SE_KEY, K_MOUSE4, qtrue, 0, NULL );
-			else
-				Sys_QueEvent( od.dwTimeStamp, SE_KEY, K_MOUSE4, qfalse, 0, NULL );
-			break;
-
-		case DIMOFS_BUTTON4:
-			if (od.dwData & 0x80)
-				Sys_QueEvent( od.dwTimeStamp, SE_KEY, K_MOUSE5, qtrue, 0, NULL );
-			else
-				Sys_QueEvent( od.dwTimeStamp, SE_KEY, K_MOUSE5, qfalse, 0, NULL );
-			break;
-
 		case DIMOFS_Z:
 			value = od.dwData;
 			if (value < 0) {
@@ -419,16 +386,29 @@ void IN_DIMouse( int *mx, int *my ) {
 		}
 	}
 
-	// read the raw delta counter and ignore
-	// the individual sample time / values
+	// read immediate device state for axes and buttons
 	hr = IDirectInputDevice8_GetDeviceState(g_pMouse,
 			sizeof(DIMOUSESTATE2), &state);
 	if ( FAILED(hr) ) {
 		*mx = *my = 0;
 		return;
 	}
+
 	*mx = state.lX;
 	*my = state.lY;
+
+	// generate button press/release events from immediate state.
+	// comparing against previous state avoids stuck buttons entirely —
+	// if a press or release was missed in the buffer, the immediate
+	// state catches it next frame.
+	for ( i = 0; i < 5; i++ ) {
+		BYTE down = state.rgbButtons[i] & 0x80;
+		if ( down != oldButtons[i] ) {
+			Sys_QueEvent( g_wv.sysMsgTime, SE_KEY, buttonKeys[i],
+						  down ? qtrue : qfalse, 0, NULL );
+			oldButtons[i] = down;
+		}
+	}
 }
 
 /*