From 8fee82d1fd9d8875cca7f8bfc577c60d12a5b5b6 Mon Sep 17 00:00:00 2001 From: Sam Lantinga Date: Tue, 21 Sep 2021 18:15:09 -0700 Subject: [PATCH] Improve relative motion handling over RDP CR and research: @danielj --- src/video/windows/SDL_windowsevents.c | 79 ++++++++++++++++++++++++--- src/video/windows/SDL_windowsmouse.c | 20 +++++++ src/video/windows/SDL_windowswindow.h | 1 + 3 files changed, 92 insertions(+), 8 deletions(-) diff --git a/src/video/windows/SDL_windowsevents.c b/src/video/windows/SDL_windowsevents.c index 5370631aa..b6556f1ad 100644 --- a/src/video/windows/SDL_windowsevents.c +++ b/src/video/windows/SDL_windowsevents.c @@ -747,23 +747,86 @@ WIN_WindowProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam) if ((rawmouse->usFlags & 0x01) == MOUSE_MOVE_RELATIVE) { SDL_SendMouseMotion(data->window, mouseID, 1, (int)rawmouse->lLastX, (int)rawmouse->lLastY); } else if (rawmouse->lLastX || rawmouse->lLastY) { + /* This is absolute motion, probably over RDP + + Notes on how RDP appears to work, as of Windows 10 2004: + - SetCursorPos() calls are cached, with multiple calls coalesced into a single call that's sent to the RDP client. If the last call to SetCursorPos() has the same value as the last one that was sent to the client, it appears to be ignored and not sent. This means that we need to jitter the SetCursorPos() position slightly in order for the recentering to work correctly. + - User mouse motion is coalesced with SetCursorPos(), so the WM_INPUT positions we see will not necessarily match the positon we requested with SetCursorPos(). + - SetCursorPos() outside of the bounds of the focus window appears not to do anything. + - SetCursorPos() while the cursor is NULL doesn't do anything + + We handle this by creating a safe area within the application window, and when the mouse leaves that safe area, we warp back to the opposite side. Any single motion > 50% of the safe area is assumed to be a warp and ignored. + */ /* synthesize relative moves from the abs position */ - static SDL_Point lastMousePoint; SDL_bool virtual_desktop = (rawmouse->usFlags & MOUSE_VIRTUAL_DESKTOP) ? SDL_TRUE : SDL_FALSE; int w = GetSystemMetrics(virtual_desktop ? SM_CXVIRTUALSCREEN : SM_CXSCREEN); int h = GetSystemMetrics(virtual_desktop ? SM_CYVIRTUALSCREEN : SM_CYSCREEN); int x = (int)(((float)rawmouse->lLastX / 65535.0f) * w); int y = (int)(((float)rawmouse->lLastY / 65535.0f) * h); + int relX, relY; + RECT screenRect; + RECT hwndRect; + RECT boundsRect; + int boundsWidth, boundsHeight; - if (lastMousePoint.x == 0 && lastMousePoint.y == 0) { - lastMousePoint.x = x; - lastMousePoint.y = y; + /* Calculate relative motion */ + if (data->last_raw_mouse_position.x == 0 && data->last_raw_mouse_position.y == 0) { + data->last_raw_mouse_position.x = x; + data->last_raw_mouse_position.y = y; + } + relX = (int)(x - data->last_raw_mouse_position.x); + relY = (int)(y - data->last_raw_mouse_position.y); + + /* Calculate screen rect */ + screenRect.left = 0; + screenRect.right = w; + screenRect.top = 0; + screenRect.bottom = h; + + /* Calculate client rect */ + GetClientRect(hwnd, &hwndRect); + ClientToScreen(hwnd, (LPPOINT) & hwndRect); + ClientToScreen(hwnd, (LPPOINT) & hwndRect + 1); + + /* Calculate bounds rect */ + IntersectRect(&boundsRect, &screenRect, &hwndRect); + InflateRect(&boundsRect, -32, -32); + boundsWidth = (boundsRect.right - boundsRect.left); + boundsHeight = (boundsRect.bottom - boundsRect.top); + + if ((boundsWidth > 0 && SDL_abs(relX) > (boundsWidth / 2)) || + (boundsHeight > 0 && SDL_abs(relY) > (boundsHeight / 2))) { + /* Expected motion for warping below, ignore this */ + } else { + SDL_SendMouseMotion(data->window, mouseID, 1, relX, relY); + + if (x < boundsRect.left || x > boundsRect.right || + y < boundsRect.top || y > boundsRect.bottom) { + /* Warp back to the opposite side, assuming more motion in the current direction */ + int warpX; + int warpY; + + if (x < boundsRect.left) { + warpX = boundsRect.right; + } else if (x > boundsRect.right) { + warpX = boundsRect.left; + } else { + warpX = x; + } + + if (y < boundsRect.top) { + warpY = boundsRect.bottom; + } else if (y > boundsRect.bottom) { + warpY = boundsRect.top; + } else { + warpY = y; + } + SetCursorPos(warpX, warpY); + } } - SDL_SendMouseMotion(data->window, mouseID, 1, (int)(x-lastMousePoint.x), (int)(y-lastMousePoint.y)); - - lastMousePoint.x = x; - lastMousePoint.y = y; + data->last_raw_mouse_position.x = x; + data->last_raw_mouse_position.y = y; } WIN_CheckRawMouseButtons(rawmouse->usButtonFlags, data, mouseID); } else if (isCapture) { diff --git a/src/video/windows/SDL_windowsmouse.c b/src/video/windows/SDL_windowsmouse.c index 7d004df16..da775fe13 100644 --- a/src/video/windows/SDL_windowsmouse.c +++ b/src/video/windows/SDL_windowsmouse.c @@ -28,6 +28,7 @@ HCURSOR SDL_cursor = NULL; +static SDL_Cursor *SDL_blank_cursor = NULL; static int rawInputEnableCount = 0; @@ -159,6 +160,16 @@ WIN_CreateCursor(SDL_Surface * surface, int hot_x, int hot_y) return cursor; } +static SDL_Cursor * +WIN_CreateBlankCursor() +{ + SDL_Surface *surface = SDL_CreateRGBSurfaceWithFormat(0, 32, 32, 32, SDL_PIXELFORMAT_ARGB8888); + if (surface) { + return WIN_CreateCursor(surface, 0, 0); + } + return NULL; +} + static SDL_Cursor * WIN_CreateSystemCursor(SDL_SystemCursor id) { @@ -210,6 +221,9 @@ WIN_FreeCursor(SDL_Cursor * cursor) static int WIN_ShowCursor(SDL_Cursor * cursor) { + if (!cursor) { + cursor = SDL_blank_cursor; + } if (cursor) { SDL_cursor = (HCURSOR)cursor->driverdata; } else { @@ -309,6 +323,8 @@ WIN_InitMouse(_THIS) mouse->GetGlobalMouseState = WIN_GetGlobalMouseState; SDL_SetDefaultCursor(WIN_CreateDefaultCursor()); + + SDL_blank_cursor = WIN_CreateBlankCursor(); } void @@ -318,6 +334,10 @@ WIN_QuitMouse(_THIS) rawInputEnableCount = 1; ToggleRawInput(SDL_FALSE); } + + if (SDL_blank_cursor) { + SDL_FreeCursor(SDL_blank_cursor); + } } #endif /* SDL_VIDEO_DRIVER_WINDOWS */ diff --git a/src/video/windows/SDL_windowswindow.h b/src/video/windows/SDL_windowswindow.h index e64096cda..b7d1ce1e0 100644 --- a/src/video/windows/SDL_windowswindow.h +++ b/src/video/windows/SDL_windowswindow.h @@ -52,6 +52,7 @@ typedef struct SDL_bool windowed_mode_was_maximized; SDL_bool in_window_deactivation; RECT cursor_clipped_rect; + SDL_Point last_raw_mouse_position; struct SDL_VideoData *videodata; #if SDL_VIDEO_OPENGL_EGL EGLSurface egl_surface;