add log of exceptions to help tracking the rare crash.

fix incorrect snapshot area when dpi setting is not 100%.

.gitignore

@@ -1,5 +1,6 @@
 build
 release
+bin/crash.txt
 
 *.pdb
 *.exp

changelog.txt

@@ -1,12 +1,17 @@
 
+v0.3.4 (ongoing)
+=================
+- Log unhandled exceptions to a file to help tracking rare crashes.
+- Fix incorrect snapshot area when the DPI setting is not 100%. (not fully tested)
+
 v0.3.3 (Jul. 10, 2016)
 =================
 - Change system tray icon size.
 - Do not quit drawing after snapshot if there are inks.
 
 v0.3.2 (Feb. 1, 2016)
 =================
-- Click throung mode has a dedicated button now.
+- Click through mode has a dedicated button now.
 - Add two new pens, to a total of five.
 - Add an entry to pen settings.
 

src/FormDisplay.cs

@@ -223,6 +223,18 @@ public void SnapShot(Rectangle rect)
 			//tempbmp.Dispose();
 
 			IntPtr screenDc = GetDC(IntPtr.Zero);
+
+			const int VERTRES = 10;
+			const int DESKTOPVERTRES = 117;
+			int LogicalScreenHeight = GetDeviceCaps(screenDc, VERTRES);
+			int PhysicalScreenHeight = GetDeviceCaps(screenDc, DESKTOPVERTRES);
+			float ScreenScalingFactor = (float)PhysicalScreenHeight / (float)LogicalScreenHeight;
+
+			rect.X = (int)(rect.X * ScreenScalingFactor);
+			rect.Y = (int)(rect.Y * ScreenScalingFactor);
+			rect.Width = (int)(rect.Width * ScreenScalingFactor);
+			rect.Height = (int)(rect.Height * ScreenScalingFactor);
+
 			IntPtr hDest = CreateCompatibleDC(screenDc);
 			Bitmap tempbmp = new Bitmap(rect.Width, rect.Height);
 			IntPtr hBmp = tempbmp.GetHbitmap();

src/Program.cs

@@ -1,6 +1,9 @@
 using System;
 using System.Collections.Generic;
 using System.Windows.Forms;
+using System.Threading;
+using System.Diagnostics;
+using System.IO;
 
 namespace gInk
 {
@@ -12,11 +15,97 @@ static class Program
 		[STAThread]
 		static void Main()
 		{
+			Application.ThreadException += new ThreadExceptionEventHandler(UIThreadException);
+			Application.SetUnhandledExceptionMode(UnhandledExceptionMode.CatchException);
+			AppDomain.CurrentDomain.UnhandledException += new UnhandledExceptionEventHandler(UnhandledException);
+
 			Application.EnableVisualStyles();
 			Application.SetCompatibleTextRenderingDefault(false);
 
 			new Root();
 			Application.Run();
 		}
+
+		private static void UIThreadException(object sender, ThreadExceptionEventArgs t)
+		{
+			DialogResult result = DialogResult.Cancel;
+			try
+			{
+				Exception ex = (Exception)t.Exception;
+
+				string errorMsg = "UIThreadException\r\n\r\n";
+				errorMsg += "Oops, gInk crashed! Please include the following information if you plan to contact the developers (a copy of the following information is stored in crash.txt in the application folder):\r\n\r\n";
+				errorMsg += ex.Message + "\r\n\r\n";
+				errorMsg += "Stack Trace:\r\n" + ex.StackTrace + "\r\n\r\n";
+				WriteErrorLog(errorMsg);
+
+				errorMsg += "!!! PLEASE PRESS ESC KEY TO EXIT IF YOU FEEL YOUR MOUSE CLICK IS BLOCKED BY SOMETHING";
+				ShowErrorDialog("UIThreadException", errorMsg);
+			}
+			catch
+			{
+				try
+				{
+					MessageBox.Show("Fatal Windows Forms Error", "Fatal Windows Forms Error", MessageBoxButtons.AbortRetryIgnore, MessageBoxIcon.Stop);
+				}
+				finally
+				{
+					Application.Exit();
+				}
+			}
+
+			// Exits the program when the user clicks Abort.
+			if (result == DialogResult.Abort)
+				Application.Exit();
+		}
+
+		private static void UnhandledException(object sender, UnhandledExceptionEventArgs e)
+		{
+			try
+			{
+				Exception ex = (Exception)e.ExceptionObject;
+
+				string errorMsg = "UnhandledException\r\n\r\n";
+				errorMsg += "Oops, gInk crashed! Please include the following information if you plan to contact the developers:\r\n\r\n";
+				errorMsg += ex.Message + "\r\n\r\n";
+				errorMsg += "Stack Trace:\r\n" + ex.StackTrace + "\r\n\r\n";
+				WriteErrorLog(errorMsg);
+
+				ShowErrorDialog("UnhandledException", errorMsg);
+
+				if (!EventLog.SourceExists("UnhandledException"))
+				{
+					EventLog.CreateEventSource("UnhandledException", "Application");
+				}
+				EventLog myLog = new EventLog();
+				myLog.Source = "UnhandledException";
+				myLog.WriteEntry(errorMsg);
+			}
+			catch (Exception exc)
+			{
+				try
+				{
+					MessageBox.Show("Fatal Non-UI Error", "Fatal Non-UI Error. Could not write the error to the event log. Reason: " + exc.Message, MessageBoxButtons.OK, MessageBoxIcon.Stop);
+				}
+				finally
+				{
+					Application.Exit();
+				}
+			}
+		}
+
+		private static DialogResult ShowErrorDialog(string title, string errormsg)
+		{
+			return MessageBox.Show(errormsg, title, MessageBoxButtons.AbortRetryIgnore, MessageBoxIcon.Stop);
+		}
+
+		private static void WriteErrorLog(string errormsg)
+		{
+			FileStream fs = new FileStream("crash.txt", FileMode.Create);
+			StreamWriter sw = new StreamWriter(fs);
+			sw.Write(errormsg);
+			sw.Close();
+			fs.Close();
+		}
 	}
 }

src/Properties/AssemblyInfo.cs

@@ -32,5 +32,5 @@
 // You can specify all the values or you can default the Build and Revision Numbers 
 // by using the '*' as shown below:
 // [assembly: AssemblyVersion("1.0.*")]
-[assembly: AssemblyVersion("0.3.3.0")]
-[assembly: AssemblyFileVersion("0.3.3.0")]
+[assembly: AssemblyVersion("0.3.4.0")]
+[assembly: AssemblyFileVersion("0.3.4.0")]