OpenAI Retro Contest – Everything I know about JERK agent

The first approach in the OpenAI Retro Contest which I started to implement, test and modify was the JERK approach. Jerk agent is one of the baseline scripts for this contest.

You can find it here: https://github.com/openai/retro-baselines

I think it is the easiest algorithm to understand for programmers who doesn’t have any Machine Learning experience.

The pseudo-code for the JERK algorithm looks like this:

Why is this the easiest approach? Because this algorithm is based on rewards. But not the same kind of rewards like rainbow or ppo2. JERK algorithm has the moves already scripted before. It doesn’t learn the same way like the two others. Sonic runs forward and jumps and if it scores points or progresses on the level further it gets rewarded. It learns based on rewards and tries to not make the mistakes again, because making a mistake will cost him “reward points”. It’s somehow like with us, humans. We are motivated to do something if we get a possible reward at the end.

Read More

Tutorial: How to access variable from other class in Unity

I have dealt with this problem very often.

How to get variables from other Class in Unity? For example I’ve got one Class with public Variables and i want to get the same value of the Variable in other Class.

For Example it could be a Class which adds points to overall Score. But in other Class i show it using Unity UI System as Text.

Here is the Class with Variable which is calling the Function in other Class.

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class Score : MonoBehaviour {

  public GameObject scoreScript;
  // Use this for initialization

  public void OnTriggerEnter2D(Collider2D node)
  {
    if (node.gameObject.tag == "Apple") {
      Destroy (node.gameObject);
      ScoreMenager scorePointsScript =  scoreScript.GetComponent<ScoreMenager>();
      scorePointsScript.AddScore ();

    }
  }
}

 

And here is the Class which contains the Function where the variable points gets incremented.

using System.Collections.Generic;
using UnityEngine.UI;
using UnityEngine;

public class ScoreMenager : MonoBehaviour {
  public int points;


  Text text;

  void Awake ()
  {
    text = GetComponent<Text> ();

  }
  // Use this for initialization
  void Start () {
  }

  public void AddScore()
  {
    points++;
  }
  // Update is called once per frame
  void Update () {
    

    text.text = "Score: " + points;
  }
}

 

Don’t Forget to Add The “Score” Script to your character! And the same for ScoreMenager, which needs to be added to the UI Element.

And also don’t forget to Create the Text as GUI

Also important is the fact, that you need to change the “Tag” of your element which will be destroyed. After it increases the Score Points value.

Component > UI > Text

 

Other tutorials in the series:

How to make the objects fall in Unity

Making Objects Fall Random On The Screen in Unity

How to Speed Up (Increase Speed) Time in Unity

How to create a simple countdown Timer in Unity