(Windows C++) How to simulate mouse movement in FPS games? - c++

Question

I'm trying to simulate mouse movement in FPS games, more specifically Valorant. I am aware of the
SetCursorPos() function and the mouse_event() function, which both work fine for changing the cursor's position. This works in FPS games that use the technique of constantly centering the cursor, but Valorant doesn't seem to do that. I wrote a program to constantly check my cursor's position (using GetCursorPos()) and my cursor never got centered, if I moved the mouse to a corner and then kept moving it, my character kept rotating. So, how does Valorant sense that I'm moving my mouse when my cursor's position isn't changing, and how can I counter that and simulate mouse movement in Valorant?
By the way, don't worry - I'm not trying to cheat, just trying to make smooth motions in freecam for cinematic shots.

Answer 1

I'm not sure how Valorant is implemented, but I can use the RegisterRawInputDevices to get the mouse event when the cursor's position isn't changing:
#include <windows.h>
#include <iostream>
using namespace std;
BOOL registerTouchpadForInput(HWND hWnd)
{
RAWINPUTDEVICE rid;
rid.dwFlags = RIDEV_NOLEGACY | RIDEV_INPUTSINK;
rid.usUsagePage = 1;
rid.usUsage = 2;
rid.hwndTarget = hWnd;
return RegisterRawInputDevices(&rid, 1, sizeof(rid));
}
static LRESULT CALLBACK NVTouch_WindowProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
BOOL registrationStatus = false;
switch (message)
{
case WM_CREATE:
registrationStatus = registerTouchpadForInput(hwnd);
break;
case WM_DESTROY:
PostQuitMessage(0);
break;
case WM_INPUT:
printf("WM_INPUT ");
return DefWindowProc(hwnd, message, wParam, lParam);
default:
return DefWindowProc(hwnd, message, wParam, lParam);
}
return 0;
}
int main()
{
WNDCLASSEX wndclass = {
sizeof(WNDCLASSEX),
CS_DBLCLKS,
NVTouch_WindowProc,
0,
0,
GetModuleHandle(0),
LoadIcon(0,IDI_APPLICATION),
LoadCursor(0,IDC_ARROW),
HBRUSH(COLOR_WINDOW + 1),
0,
L"myclass",
LoadIcon(0,IDI_APPLICATION)
};
bool isClassRegistered = false;
isClassRegistered = RegisterClassEx(&wndclass);
if (isClassRegistered)
{
HWND window = CreateWindow(wndclass.lpszClassName, NULL, 0, 0, 0, 0, 0, HWND_MESSAGE, NULL, GetModuleHandle(0), NULL);
if (window)
{
ShowWindow(window, SW_SHOWDEFAULT);
MSG msg;
while (GetMessage(&msg, 0, 0, 0))
{
TranslateMessage(&msg);
DispatchMessage(&msg);
}
}
}
}
And then, use SendInput to simulate the relative mouse move at the border of the screen:
INPUT buffer;
ZeroMemory(&buffer, sizeof(buffer));
buffer.type = INPUT_MOUSE;
buffer.mi.dx = 10;
buffer.mi.dy = 10;
buffer.mi.mouseData = 0;
buffer.mi.dwFlags = MOUSEEVENTF_MOVE;
buffer.mi.time = 0;
buffer.mi.dwExtraInfo = 0;
while (1)
{
Sleep(1000);
SendInput(1, &buffer, sizeof(INPUT));
}