public static void FullscreenOn() { if (gameWindow == IntPtr.Zero) { IntPtr[] possibleWindows = GetPossibleWindows(); if (possibleWindows.Length == 0) { return; } else if (possibleWindows.Length == 1) { gameWindow = possibleWindows[0]; } else { FormSelectApp.instance.UpdateWindowsList(possibleWindows); if (FormSelectApp.instance.ShowDialog() == DialogResult.OK) { gameWindow = FormSelectApp.instance.GetSelectedWindow(); if (gameWindow == IntPtr.Zero) { return; } } else { return; } } } Rectangle rect = PInvokeFunc.GetWindowRect(gameWindow); int w = rect.Width; int h = rect.Height; int fullX = -1; int fullY = -1; int[,] sizes = { { 640, 480 }, { 800, 600 }, { 1024, 768 }, { 1152, 720 }, { 1152, 864 }, { 1280, 720 }, { 1280, 768 }, { 1280, 800 }, { 1280, 960 }, { 1280, 1024 }, { 1360, 768 }, { 1440, 900 }, { 1600, 900 }, { 1600, 1024 }, { 1600, 1200 } }; int minD = int.MaxValue; for (int i = 0; i <= sizes.GetUpperBound(0); ++i) { int dx = w - sizes[i, 0]; int dy = h - sizes[i, 1]; int d = dx * dx + dy * dy; if (d <= minD) { minD = d; fullX = sizes[i, 0]; fullY = sizes[i, 1]; } } Global.windowPosition.MainFormPosition = WindowPosition.Serialize(Form1.thisForm); if (Form1.thisForm.formOptions != null) { Global.windowPosition.OptionsFormPosition = WindowPosition.Serialize(Form1.thisForm.formOptions); } if (FormMonitor.isCreated()) { Global.windowPosition.MonitorFormPosition = WindowPosition.Serialize(FormMonitor.instance); } oldGameLocation = new Point(rect.Left, rect.Top); fullscreen = true; try { if (dxDevice == null) { dxDevice = new Device(); } dxDevice.SetDisplayMode(fullX, fullY, 32, 0, true); int border = (rect.Width - fullX) / 2; PInvokeFunc.SetWindowPos(gameWindow, IntPtr.Zero, -border, fullY - rect.Height + border, 0, 0, 5); WindowPosition.Deserialize(Form1.thisForm, Global.windowPosition.FullscreenPosition); if (Form1.thisForm.Width > fullX) { Form1.thisForm.Width = fullX; } if (Form1.thisForm.Height > fullY) { Form1.thisForm.Height = fullY; } if (Form1.thisForm.Left + Form1.thisForm.Width > fullX) { Form1.thisForm.Left = fullX - Form1.thisForm.Width; } if (Form1.thisForm.Top + Form1.thisForm.Height > fullY) { Form1.thisForm.Top = fullY - Form1.thisForm.Height; } Form1.thisForm.TopMost = true; } catch (Exception) { FullscreenOff(); } }