How to debug why Unity freezes? - unity3d

Question

I am doing a collaboration with my school mates for a school project, but recently when I run Unity it freezes and I can't get it to unfreeze. I have uninstalled and reimported all the assets and my group mates also said that their Unity does not have this problem. I can't find a solution.
The project is being done in 2d. I was testing some logic while this happened to me. I was making a health bar test where it automatically goes down and there's a text box while follows it containing the actual number. Then suddenly the next day Unity decided to quit on me and not run at all.
Update
Code:
public static float fillamount = 1f;
public float period = 1f;
public Image image;
private float time;
public float DoesItDecreaseOverTime = -0.1f;
private float tempnum;
// Use this for initialization
void Start () {
}
// Update is called once per frame
void Update () {
time += Time.deltaTime;
while (fillamount <100 || fillamount > 0)
{
if (time >= period)
{
fillamount += DoesItDecreaseOverTime;
time = 0;
}
}
tempnum = (fillamount * 100);
image.fillAmount = fillamount;
}
}

Answer 1

After long days of frustration myself, I have found how to debug while unity freezes. I was doing stuff with trees (not the vegetation, the data structure) and for me it was very hard to determine where and what causes stack overflow. The stack overflow freezes unity so I can't see any debug that would have helped me to solve the problem. But now, I found the solution.
SOLUTION
So, I tried using System.Diagnostics.Debug.WriteLine which you should see in the output window of Visual Studio. But that doesn't seem to work with a unity project. Anyways, I started to think a little bit and came up with this class:
using System;
using System.IO;
public class Logger
{
public Logger(string logFilePath)
{
if(!logFilePath.EndsWith(".log"))
logFilePath += ".log";
LogFilePath = logFilePath;
if(!File.Exists(LogFilePath))
File.Create(LogFilePath).Close();
WriteLine("New Session Started");
}
public string LogFilePath { get; private set; }
public void WriteLine(object message)
{
using(StreamWriter writer = new StreamWriter(LogFilePath, true))
writer.WriteLine(DateTime.Now.ToString() + ": " + message.ToString());
}
}
Usage is like this:
Logger logger = new Logger(#"C:\Users\Soogbad\Desktop\MyLog.log");
logger.WriteLine("Hello World");
This creates a log file in which you can see all the logs you made. It works perfect! Even while unity is freezing.

Answer 2

Try to avoid Loops in the update function (unless you fully control the loop), this function is called everyframe so if you perform long tasks in here you might experience framedrop and freezes.
In your case replace the while by a If and revert the conditions.
If you have unity pro you have the Profiler that will tell you what script/function is taking the most cpu time.