From 960aff24fc7a238a11276e5b5ac650ce76bd61db Mon Sep 17 00:00:00 2001 From: Ahmed Samy Date: Tue, 27 Jan 2026 00:43:09 +0200 Subject: [PATCH] Backends: Win32: use XInput Packet to avoid resubmitting gamepad data. (#9202, #8556) --- backends/imgui_impl_win32.cpp | 8 ++++++++ docs/CHANGELOG.txt | 2 ++ 2 files changed, 10 insertions(+) diff --git a/backends/imgui_impl_win32.cpp b/backends/imgui_impl_win32.cpp index c344a1417..de92040aa 100644 --- a/backends/imgui_impl_win32.cpp +++ b/backends/imgui_impl_win32.cpp @@ -21,6 +21,7 @@ // CHANGELOG // (minor and older changes stripped away, please see git history for details) +// 2026-01-28: Inputs: Minor optimization not submitting gamepad input if packet number has not changed (reworked from 2025-09-23 attempt). (#9202, #8556) // 2025-12-03: Inputs: handle WM_IME_CHAR/WM_IME_COMPOSITION messages to support Unicode inputs on MBCS (non-Unicode) Windows. (#9099, #3653, #5961) // 2025-10-19: Inputs: Revert previous change to allow for io.ClearInputKeys() on focus-out not losing gamepad state. // 2025-09-23: Inputs: Minor optimization not submitting gamepad input if packet number has not changed. @@ -127,6 +128,7 @@ struct ImGui_ImplWin32_Data HMODULE XInputDLL; PFN_XInputGetCapabilities XInputGetCapabilities; PFN_XInputGetState XInputGetState; + DWORD XInputPacketNumber; #endif ImGui_ImplWin32_Data() { memset((void*)this, 0, sizeof(*this)); } @@ -358,6 +360,9 @@ static void ImGui_ImplWin32_UpdateGamepads(ImGuiIO& io) if (!bd->HasGamepad || bd->XInputGetState == nullptr || bd->XInputGetState(0, &xinput_state) != ERROR_SUCCESS) return; io.BackendFlags |= ImGuiBackendFlags_HasGamepad; + if (bd->XInputPacketNumber != 0 && bd->XInputPacketNumber == xinput_state.dwPacketNumber) + return; + bd->XInputPacketNumber = xinput_state.dwPacketNumber; #define IM_SATURATE(V) (V < 0.0f ? 0.0f : V > 1.0f ? 1.0f : V) #define MAP_BUTTON(KEY_NO, BUTTON_ENUM) { io.AddKeyEvent(KEY_NO, (gamepad.wButtons & BUTTON_ENUM) != 0); } @@ -771,6 +776,9 @@ IMGUI_IMPL_API LRESULT ImGui_ImplWin32_WndProcHandlerEx(HWND hwnd, UINT msg, WPA case WM_SETFOCUS: case WM_KILLFOCUS: io.AddFocusEvent(msg == WM_SETFOCUS); +#ifndef IMGUI_IMPL_WIN32_DISABLE_GAMEPAD + bd->XInputPacketNumber = 0; // FIXME: Technically, calling io.ClearInputKeys() directly would require this as well. +#endif return 0; case WM_INPUTLANGCHANGE: ImGui_ImplWin32_UpdateKeyboardCodePage(io); diff --git a/docs/CHANGELOG.txt b/docs/CHANGELOG.txt index 1207595d2..80bd16b19 100644 --- a/docs/CHANGELOG.txt +++ b/docs/CHANGELOG.txt @@ -229,6 +229,8 @@ Other Changes: devices. (#8784) [@FelixStach] - Win32: handle `WM_IME_CHAR`/`WM_IME_COMPOSITION` to support Unicode inputs on MBCS (non-Unicode) Windows. (#9099, #3653, #5961) [@ulhc, @ocornut, @Othereum] + - Win32: minor optimization not submitting gamepad input if packet number has not + changed (reworked previous 1.92.4). (#9202, #8556) [@AhmedSamyMousa, @MidTerm-CN] - Examples: - Win32+DirectX12: ignore seemingly incorrect `D3D12_MESSAGE_ID_FENCE_ZERO_WAIT` warning on startups on some setups. (#9084, #9093) [@RT2Code, @LeoGautheron]