Dev Blog

Unity Programming – Delegates and Events

digm520admin / / C#, Programming, Terminology, Tutorial, Unity
March 18, 2019

Unity Programming – Delegates and Events

Tutorials and Definitions

Youtube – Delegates – Unity Official Tutorials

By: Unity

Youtube – Events – Unity Official Tutorials

By: Unity

The scene management update has made significant progress, I am now currently loading and unloading the proper scenes at the proper times. The timing of the loading and unloading is still off however, as well as the fading animation timing is very strange. The fading error makes sense since I have the scene transition and the fading in the same method currently, so I will look to separate those and time them properly with IEnumerators. I was also told today that OnSceneLoad delegates would be a very helpful feature for me to look into to fix all my scene loading timings.

The basic IEnumerator timing I was also suggested to look into was: wait until animation is done, wait until next scene is loaded, then unload scenes to be unloaded.

Upon investigating delegates, I found that they are a very big part of coding in general. Looking into delegates also led me to events, which are somewhat like a specialized type of delegate. I believe understanding both of these will be very beneficial to my current scene loading issues, as well as being very useful for many other game programming purposes, so I wanted to take the time to better understand them before rushing back to my scene development needs.

TERMINOLOGY

Delegates

Delegates: Simply a container for a function that can be passed around, or used as a variable. Just like variables, delegates can have values assigned to them and can be changed at runtime. The difference is that while variables contain data, delegates contain functions.

First you create a delegate template with the delegate keyword. This dictates what types of methods we can assign to the delegate. Similar to a function, a delegate has: a return type, a name, and a parameter list. The methods you want to add to this delegate must have both the same type of return type and parameter list. You then have to declare a member variable with the type of the delegate you created.
Example:
delgate void MyDelegate(int num)
MyDelegate myDelegate

Then, you can either assign methods to the delegate as values directly, or add/remove methods from the delegate with the += or -= operators respectively. Adding several methods to a single delegate is called multicasting.

The example from the Unity Official Tutorial I linked is as follows: using UnityEngine;
using System.Collections;

public class MulticastScript : MonoBehaviour
{
delegate void MultiDelegate();
MultiDelegate myMultiDelegate;


void Start ()
{
myMultiDelegate += PowerUp;
myMultiDelegate += TurnRed;

if(myMultiDelegate != null)
{
myMultiDelegate();
}
}

void PowerUp()
{
print (“Orb is powering up!”);
}

void TurnRed()
{
renderer.material.color = Color.red;
}
}

This shows the potential of a multicast delegate. On start, the PowerUp and TurnRed methods are both added to the myMultiDelegate delegate (which is possible since both methods have return type of void with no parameter list, just as the delegate does). Now anytime afterward, if the myMultiDelegate is called, it will perform all of the methods added to it (in this case both PowerUp and TurnRed). It is also noted that if you want to remove methods from myMultiDelegate, just use the -= operator along with the name of the method you want to remove.

One final note was that attempting to use a delegate that has not been assigned anything will cause an error. In this case, a delegate will have its default value, which is null. This is why they show in the tutorial that it is good practice to check that the delegate is !null before attempting to use it.

Events

Events: specialized delegates that are useful when you want to alert other classes that something has happened. An event can be thought of as a broadcast system. Any class interested in an event can subscribe methods to it. When that specific situation occurs, the event is invoked, which calls the methods of the subscribed classes. So an event is just like a delegate classes can send methods to, and then when that event is called, all of those methods will happen.

In the Unity Event tutorial I linked, they start by creating an EventManager script they place on the camera (this might be different with Event Systems now, this is an old tutorial). They then create a public delegate, which is then the type used for the public static event they create. So it appears that an event might be something similar to a list of delegates, and you add the type of delegate to it to determine what types of methods you can subscribe to this event. The tutorial then ties the event to a button press. Now any time this button is pressed, every method subscribed to the event will be invoked.

To show the broadcasting nature of events, there are two separate game objects with two separate scripts attached to them that subscribe different methods to the same event. They also show the proper fundamental practice of dealing with events. The scripts subscribe their methods to the event OnEnable, and unsubscribe them OnDisable (this is similarly does as with delegates; the += operator subscribes a method to an event, and the -= operator removes the method). It is a good rule of thumb that every time you subscribe a method to an event, you should create a corresponding unsubscribe for it as well. Failing to do this properly can lead to memory leaks and other various errors.

They then describe why this system is effect for dealing with action in your game. The event manager only needs to worry about the event itself and the triggers for the event. It does not need to know about the Teleport of TurnColor script, and these two scripts didn’t need to know about each other either. This helps create a flexible broadcast system.

They then describe the difference between using a public delegate and the event they created. They state that you could acheive the same effect this way, since events are just specialized delegates. The reason to use an event here is that they have inherent security. Events ONLY allow other classes to subscribe and unsubscribe. If a delegate was used, other classes could invoke it or overwrite it.

The take away: if you want to create a dynamic method system that involves more than one class, use event variables instead of delegate variables.

Unity Scene Management – Timed Loading and Build Indexing

digm520admin / / Programming, SceneManagement, TowerDefense, Unity
March 17, 2019

Advancing Tower Defense Tutorial

Altering Scene Format

Youtube – Unity- Scene Manager and Keeping Objects when Loading/Unloading

By: Egon Everest

Myriad Games Studio – HOW TO USE THE UNITY SCENEMANAGER

I continued to updated the scene management of my tower defense tutorial. One of the biggest additions was that I did decide to create a single location for all of the OverlayCanvas button methods I wanted to use. This was just a script called the OverlayCanvasManager that I added to the GameManager object. This just made sense with how often different UI buttons would do similar actions, like going to the menu. This script then became the sole reference point between the Base Scene and the SceneManagerLite object in the Logic Scene.

As I was working with the references between the OverlayCanvasManager and the SceneManagerLite, it became more clear that the SceneManagerLite should still directly handle all of the actual scene management. The OverlayCanvasManager would then become the reference to use for the OverlayCanvas buttons (since I needed an object to drag in the inspector for the buttons, but that has to be within the same scene), and would basically tell the SceneManagerLite what to do based on what buttons were pressed.

Having the SceneManagerLite be directly responsible for everything scene related also made more sense for holding variable values. Now instead of several scripts needing to have information about different build indices for scenes like the Main Menu or the Current Level, this information could just be kept in this one location and updated much more easily.

PROBLEMS

The first main issue I was having with this setup is that the loading times of the scenes appear to be off. Sometimes the scenes would overlap because the next one would be finished loading before the previous was unloaded. I need to be able to perform some sort of check to do one after the other, or have some simple UI setup to block the process until everything is properly loaded.

The next big issue I had was debugging all of these new scene transitions. I updated every instance of transitioning between scenes, so making sure these all went to the right place took some time. I also had an issue where using the Menu or Retry methods from the OverlayCanvasManager (which tied in to the Menu or RetryLevel methods of the SceneManagerLite) was unloading my Logic Scene and just loading unintended scenes. My debugging led me to believe that this was an issue with the data transfer from the Current Level Scene to the SceneManagerLite.

As part of having all of the build index information be in the SceneManagerLite, I needed a way for it to know the build index of whatever the Current Level Scene was. I could not get this information from anything in the Base Scene, as this has its own build index. To solve this, I created a very simple object in the Level Scene, SceneInformation, that would have a script, SceneInformation, that set the currentLevelBuildIndex value in the SceneManagerLite to this object’s scene build index at Start. This was not happening however, as when I Debugged the Menu method, it was showing me that the currentLevelBuildIndex was 0. This showed me why the Logic Scene was being unloaded, and that this value was not being updated, as it was remaining at its default of 0.

I think what is causing the issue is that I am using the SceneManager GetActiveScene method, and this may not be doing what I thought it did. This is the suggested method to get your scene’s build index normally, but this may not be the case when you have multiple. If there are multiple, the ActiveScene may not necessarily be the one the object is in.

NOTES

From the problems I ran into, I had to do more research on the SceneManager for Unity, specifically what an active scene meant. The active scene is the scene that objects are created in whenever objects are instantiated. So if you have multiple scenes open, instantiated objects do NOT automatically appear in the scene of the script instantiating them. Everything from any scene that is instantiated will go to the one designated active scene. When you add scenese additively, the active scene does not change.

With this information, I updated my SceneManagerLite so its transition would now set the newly loaded scene as the active scene as well. This makes sense as I don’t want the Logic Scene to be where objects are instantiated, so immediately making newly loaded scenes active removes it from being the active scene. This also helped my issue with finding the build index of the Current Level scene. It’s obvious I want that to be the active scene when the player is in game, and now using the SceneManager method GetActiveScene will properly return the build index of the Current Level scene itself.

This ideally works in theory, but I ran into a new issue where I could not set the newly loaded scenes as active because Unity did not think they were loaded yet. I got the error message:

ArgumentException: SceneManager.SetActiveScene failed; scene ‘Level01’ is not loaded and therefore not set to active

This seemed to be caused by an issue where loading scenes takes a bit of time, so it wasn’t loaded when Unity was calling to set the scene to active. I investigated a solution with IEnumerators for this.

Looking into IEnumerators to deal with the timing issue for setting my active scene led me to this great scene management source by Myriad Games Studio. They had the script written out for a clean asynchronous scene loader. I used this as the basic foundation for a Scene Loader of my own. I needed to tweak it some for my additive scene needs, and I decided to not use the Singleton class they used for now just to keep it simpler. This now set the active scene specifically after loading the scene, so this solved that issue! Now however, I found out it was loading the wrong scene index.

The reason I was loading the wrong build index now with my Menu and Retry methods is because the SceneInformation script that was getting that active build index at Start was returning a value of 1. I had it return the active scene build index in Update to see if it ever changed, and it would correctly change to 4 on the second frame. Not only did it return 1 in Start, it also returned 1 on the very first run of Update. Then every other instance was the proper 4. This has something to do with the fact that when I load a scene I set it active as well, so there is some delay between creating the Base Scene and creating the Level Scene where Start functions in the Level Scene run before the Level Scene is set to active.

The fact that I was loading in to the proper level though gave me an idea to fix it. The fact that the right level was initially loading meant somewhere had the build index correct, and that was the Level Selector. With this information, I simply looked into the SceneManagerLite LevelSelect method and set the currentLevelBuildIndex in there to be the value of the index that is passed in. This ensures that whatever index is loaded for the level will also be the index used for the other methods, which actually makes sense.

Unity Scene Management – Creating Project SceneManager

digm520admin / / Programming, SceneManagement, TowerDefense, Unity
March 16, 2019

Advancing Tower Defense Tutorial

Altering Scene Format

Youtube – Unity- Scene Manager and Keeping Objects when Loading/Unloading

By: Egon Everest

Following in the footsteps of the FAR team from a Unite 2017 talk, I wanted to update my scene management in the tower defense tutorial to match that from the talk. To begin, I wanted to create a general Logic Scene to hold all of my managers and a Base Scene to hold general assets consistent between levels.

To start I needed to break up my current level scenes into their various parts since these will have all of the basics for every scene we are attempting to construct…

Since the Scene Fader will be used constantly as a way to transition between any and all scenes, this was included in the Logic scene that will persist the entire time the game is open. To make this accessible to all the other scenes and scripts however, I chose to have its script create a public static instance of itself. This was copied directly from the way the BuildManager was setup (creating a simple sort of singleton reference from the Brackeys tutorial):

public static SceneFader sceneFaderInstance;

private void Awake()
{
if (sceneFaderInstance != null)
{
Debug.Log(“More than one Scene Fader in scene”);
return;
}
sceneFaderInstance = this;
}

This way I could just go into all the scripts that had a public reference for the Scene Fader to drag into in the Inspector, and have the sceneFader variable to be set to SceneFader.sceneFaderInstance at Start instead of relying on the public reference.

Next I determined that I needed to figure out how to manage loading/unloading these various scenes now. Using basic Unity scene management, my scripts just load one scene at a time and unload all the current scenes. So even though I could test this by dragging in a Level scene and a Logic scene at the same time to make sure the new setup worked, everything would be back to loading one scene at a time as soon as I called a basic LoadScene method. To learn this, I went to look for a new tutorial.

I came across a Scene Manager tutorial dealing with loading/unloading objects in a more controlled manner that seemed perfect for what I was looking to do. There is a Scene Manager method called LoadSceneAsync which gives more options for how you load a scene. You give it a build index as well as a LoadSceneMode.

    LoadSceneMode has two options:

  • Single: the basic way Unity loads scenes where it also unloads all other currently loaded scenes
  • Additive: this just additionaly loads the inserted scene; this does not unload any other scenes

The Additive LoadSceneMode is the first step to accomplishing what I am looking for. At this time, I also decided it may make more sense to add some type of SceneManager object to my Logic scene to hold a SceneManager type script to deal with these functions. I did not want to run into any issues with Unity’s built in SceneManager so I just named all of this SceneManagerLite for now. This would use a similar singleton setup as referenced earlir for the BuildManager and the SceneFader.

Continuing along with this tutorial, this scene management method requires you to unload the currently loaded scene as well when needed. To do this, there was a simple Scene Manager method, UnloadScene. This is currently obsolete however but just needs replaced with UnloadSceneAsync. Similarly to LoadSceneAsync, this requires at minimum the build index of the scene you wish to unload.

So when I started to look into changing all of the scripts to fit within this new scene management scheme, I came across the realization that my Scene Fader is basically my Scene Manager Lite already. Every script that deals with changing scenes acceses the Scene Fader first to perform the “FadeOut” method created, which contains both the simple fade effect as well as the actual LoadScene method constantly being used that I wanted replaced. With this discovery, I renamed my Scene Fader to the Scene Manager Lite and made the necessary edits here. This simplified everything as now I could simply just change the FadeOut method to use the LoadSceneAsync and UnloadSceneAsync methods and it would apply to all the existing calls to that method.

I did end up needing to go through each method call and touching them up because the tutorial set the scene loading method up with a string input, and I wanted to change this to an int input to go with the build index. I figured the overall scene layout and build indices were pretty set at this point, so using build index instead of the scene names would be more consistent and easier to work with in the future as I added levels.

Outside Scene Management

Something important to note is that some of the scripts I wanted to update with the new Scene management would actually be referencing build indices for a scene other than themselves. Each of these are in the OverlayCanvas, which is an object I want to keep in the BaseScene, as all of these objects will remain consistent through every level. These are those scripts:

  • CompleteLevel: deals with functionality of UI menu when player successfully defeats a level
  • GameOver: deals with functionality of UI menu when player fails a level
  • PauseMenu: deals with functionality of UI menu when player pauses the game

This means that when they want to inform the SceneManagerLite of what scenes to load/unload, they will actually want to reference the build index of the LevelScene, not the index of their own scene (BaseScene).

Unite Europe 2017 – Multi-scene editing in Unity for FAR: Lone Sails

digm520admin / / SceneManagement, Talks, Unite, Unity, UnityEditor
March 15, 2019

Unite Europe 2017

Multi-scene editing in Unity for FAR: Lone Sails

Youtube – Unite Europe 2017 – Multi-scene editing in Unity for FAR: Lone Sails

By: Goran Saric

I wanted to look into pushing the tower defense tutorial series I did from Brackeys into a more polished little game project, so one of the first upgrades I wanted to look into for the project was the suggestion about breaking up the scenes in a more efficient manner.

This was mentioned as the best way to set up the overall project if you wanted to make it significantly larger but keep it very easy to build upon. This is because there are a lot of objects in a given level currently that will persist between every level and right now they are just copied into every single level. If you make an edit to any of these objects, they need copied into every other scene again. This can be minimized by using prefabs much more extensively, but having a scene solely for these objects keeps everything much cleaner and easier to edit.

So searching for how to properly implement this idea of broken up scenes, I came across this Unite Europe 2017 talk where the makes of FAR: Lone Sails detail exactly how they approached the used of multi-scene editing in their game.

Before getting into their general additive scene setup, they mention how they broke down the main level content from a giant full story board type setup into equally sized level scenes. They then had two level scenes loaded at any given time to keep the memory usage down to a minimum, but ensure the next scene was ready when the player arrived.

The Scene Abstraction:

  • Logic Scene
    • Always loaded
    • Contains all relevant managers to keep game running
    • Examples: Scene Manager; Save Manager
  • Base Scene
    • All elements of game that are always present during gameplay and level independent
    • Examples: character(player); camera; their giant vehicle
  • Level Content 1 Scene
    • The rest of the level content that is unique for that area/level
  • Level Content 2 Scene
    • This is the same type as the previous scene
    • Just enforcing that the game has 2 level scenes loaded at any one time

They then detail some of their work flow with these level content scenes in the editor. Even though the game only ever has two scenes loaded at once, sometimes they had several level scenes all open at once to ensure the overall theme was consistent, for aligning geometry, etc. It is also noted the Editor play time gets faster by only having the scenes loaded that you need when testing. More broken up scenes also helps reduce merge conflicts.

Helper Tools

There were two main tools they mentioned being helpful for the designers to keep them organized: Highlight Scene Borders and Teleportation Keyboard Shortcuts.

Highlight Scene Borders: This tool just had a large colored plain at the ends of the scenes to help indicate where new scenes were starting/ending when having multiple open at once. This was especially helpful since they are dealing with more of a 2D platforming game world. This just helps ensure objects are placed in the correct scene, as well as helping determine camera frustrum angles.

Teleportation Keyboard Shortcuts: They had an issue where constantly during testing they would have to slide some of the major game components through the scenes to locate them. They discovered a much easier solution to this was to just have a keyboard shortcut that teleported these constantly moving pieces to the current mouse position. If done during the running of the game, this also has an added benefit that it doesn’t mess with the editor at all and will be reset to the proper location after testing.

Scene Collection

Unity doesn’t have a built in way to save scene hierarchies in the editor yet, but there are many tutorials online about creating your own editor tools to do this. Unity offers the corresponding API to do so, it just needs some work to be user friendly. They created a scriptable object that can save the constellation of all loaded scenes to be loaded again at a later time.

Cross-Scene References

Unity does not normally allow for cross scene references between objects within the Inspector. There are several ways to access an object from another scene though.

GameObject.Find: this is very slow and can be tricky to find the correct instance

Singleton/Statics: most programmers dislike using these, but they can be used for this purpose

Scriptable Objects: keep references of instances in a scriptable object and link them to your scripts

Zenject – Dependency Injection Framework: offers some built-in features to support reference injections over multiple scenes

For FAR, they didn’t need to do very many cross scene references in the way they setup the scenes. When they did need to do this however, they had a simple monobehavior component in the Base Scene which would access a reference in a static reference pool. This static field reference could then be influenced/updated by simple monobehavior components in the current Level Scene. This exposes some of the methods from that original component in the Base Scene. Their setup also helps keep the Level Designers from messing with scripts they shouldn’t be modifying.

Finally, if you want some really advanced features already setup for you, there is a tool you can buy on the Unity store. It’s titled “Advanced Multi-Scene: Cross-Scene References”. It has some nice features such as scene merging and cross scene Inspector referencing.

Unity ML Agents – Setup

digm520admin / / MachineLearning, Programming, Tutorial, Unity
March 15, 2019

Unity ML Agents

Balancing Ball Setup


Basic Project Settings

Make sure the “Scripting Runtime Version” for every platform you are targeting to build is set to (.NET 4.6 Equivalent or .NET 4.x Equivalent). I had to update the project to work with Unity 2018 and it already had .NET 4.x Equivalent as the default setting for all of my platforms.

Overall GameObject Hierarchy

The overall platform prefab has a “Ball 3D Agent” script which needs a brain property

The brain object then holds a Tensor Flow model property

Setting Up Training Environments

There are two ways to train your objects: in the Unity Scene Editor in by using an executable.

The first example will train in the Unity scene editor. This is done by accessing the “Ball 3D Academy” object, adding “3DBallLearning” brain to the Broadcast Hub of the “Ball 3D Academy” script, and checking the Control check box. The Broadcast Hub exposes the brain to the Python process, and the Control checkbox allows that Python process to control the brain.

Next I needed to use Anaconda Prompt to run the learning processes. Since I’m still getting the hang of this, I ran into a few basic issues noted in the PROBLEMS section.

After successfully completing the training, the trained model is located at path:

models/<run-identifier>/<brain_name>.nn

You then want to bring your model (the .nn file) into your Unity project, and then set this as the model property for the brain you are using.

Problems

Apparently I did not follow the default installation setup, so I was unable to access “mlagents-learn” from any directory. I found my ml-agents folder location and learned how to change my directory in Anaconda Prompt to get myself into the correct location. This then allowed the first step to properly process, which was running the line:

mlagents-learn config/trainer_config.yaml –run-id=firstRun –train

After resolving this step, I was getting a UnityTimeOutException error in Anaconda Prompt. This was just because Unity was unable to communicate with the Python process because I forget to check the Control checkbox from the tutorial.

Finally, when I went to add my newly trained model to the Learning Brain and play the scene, I got an error and the platforms did not move at all. I did not reopen the scene like stated in the tutorial notes, and determined a default value of the scene might have still been altered. It turned out I just needed to uncheck the Control check box in the Brain Hub, which makes sense since that determines if the platforms are run by the outside Python process or not. Turning this off allowed them to perform on their own with the designated model properly again.

NEXT STEPS

These are the next steps suggested by the end of this small setup tutorial:

Intro to Python Programming with Mosh – Pt. 02

digm520admin / / Programming, Python, Tutorial

Intro to Python Programming with Mosh – Pt. 02

March 14, 2019

Intro to Python Programming

Tutorial – 02

Youtube – Learn Python 3 for Machine Learning & Web Development [2019]

By: Programming with Mosh
Progress

End Time: 48:40

Next Part of Tutorial: Arithmetic Operations

NOTES

Strings

You can use single or double quotes for strings, but there is a difference for certain applications. For example, if you want an apostrophe in your string, you need to use double quotes to define the string. An example for the reverse is that you use single quotes to define the string if you want something to be in double quotes within the string.

Strings can also be defined with triple quotes. This allows you to create a multiline string.

You can call a character index of a string with brackets (i.e. string[0] will return the value of the first character in that string.). An interesting feature is that you can use negative indices to start at the end of the string and count backwards.

You can also call a chunk of characters with two values separated by a colon. If you don’t place a number before the colon, 0 will be assumed. If you don’t place a number after the colon, the length of the string is assumed. Using these together, you can perform a simple duplication of a string (i.e. another_string = string[:]).

The final check with this colon/index syntax was what would happen if you entered:
string[1:-1]
Where string was ‘Jennifer’. This returned ‘ennife’, which appears to indicate this syntax always returns values from left to right if possible, as well as showing that the beginning value is inclusive, while the final value is exclusive. To further test this, I tried string[3:1] and this did not return any value, which fit my thought on “left to right is possible”.

Formatted Strings

Formatted strings are used to make complex strings easier to visualize their output. Formatted strings are indicated with quotes starting with an f (i.e. f’text’). They then use curly brackets to create holes in the string where variables can be placed.

String Methods

The first basic method is len(). This returns the value of the number of characters in a string. This function is general purpose though, so it can count the number of objects in a list as well for example. The fact that it is general purpose is what makes it a function, as opposed to a method.

We looked into the find() method for strings. This takes an input of characters and returns the index of the first instance of those characters in the associated string. You can enter a single character or entire words to search for. Multiple characters will return the index of where those characters start.

The replace() method takes two inputs; the first input is what it searches for in the string, and the second input is what it replaces that with.

Next we used the “in” operator. Using the format of:
‘characters’ in string_variable
This returns a bool value of whether those characters are found within the string value indicated.

TERMINOLOGY

  • Method: in object oriented programming, a function that belongs to or is specific to some object

SUMMARY

The main difference between a function and a method is that a function is more general purpose, where as a method is something belonging to a specific type of object.

The string topics covered here gave me a lot of new information. I’m interested to see if there is any overlap with some of this in C# for Unity programming since there’s a lot of really helpful functions and methods covered. The formatted strings are especially nice to keep code nice and tidy instead of having those ugly string concatenation lines.

Intro to Python Programming with Mosh – Pt. 01

digm520admin / / Programming, Python, Tutorial
March 13, 2019

Intro to Python Programming

Tutorial – 01

Youtube – Learn Python 3 for Machine Learning & Web Development [2019]

By: Programming with Mosh
Progress

End Time: 29:35

Next Part of Tutorial: Strings

NOTES

This tutorial covers the complete basics of Python, starting with installing it, so it is as beginner friendly as you can get. The entire tutorial will use these basic foundational teachings to lead into creating projects to show how to use what you learn in a functional sense. These projects include a shopping site, an AI system for helping a user get music to match their preference, and a spreadsheet processing program.

Upon installation, it was important to “Add Python to PATH” for Windows (which I am using). I wasn’t sure if I did that since I had installed before, so I found that this references the Path in environment variables and just adds the path of your Python folder to this list. I added my Python path to this list in hopes that would resolve that issue. The tutorial says this is critical to follow it, so I will see if I get any errors.

Next we grabbed a code editor. The suggested one to use was PyCharm. There were no special installation features or plugins mentioned to download/install so I just installed the bare minimum.

In Python, you can define a string with single or double quotes. You can also multiply a string with a number to print that string that number of times (i.e. ‘*’ * 10 gives **********).

Standard variable types:

  • int: integer values
  • float: floating point values (those with decimal points)
  • string: words/text
  • bool: true/false
  • lists
  • objects

Next we finally got into receiving input from the user. This uses a Python function simply called Input(). The input from the user for this will also initially be created as a string variable, so make sure to convert this to int, float, etc. for your needs.

TERMINOLOGY

  • Expression: a piece of code that produces a value
  • Variable: allocation of memory for a specified value

SUMMARY

So far the basics seem very similar to what I’ve already learned in C++/C#, with the standard variable types and simple functions. I am speeding through these early parts, but don’t want to jump ahead since I want to make sure I don’t miss anything that does happen to differentiate from what I already know. This is also a good refresher for basic programming terminology and getting another view on the underlying basics of coding.

Coroutine Basics in Unity

digm520admin / / Programming, TutorialList, Unity
March 12, 2019

Coroutines in Unity

Resources On Coroutines

Youtube – Coroutines – Unity Official Tutorials

By: Unity

Youtube – Introduction to Game Development (E21: coroutines)

By: Sebastian Lague

Youtube – Coroutines In Unity – What Are Coroutines And How To Use Them – Coroutines Unity Tutorial

By: Awesome Tuts

Youtube – Unity3D – 2 Ways to Start & Stop Coroutines (the good & bad ways)

By: Unity3d College

Coroutines are one of the tools I still don’t fully understand how to utilize in Unity so I wanted to gather some resources to really learn the basics. I am hoping this helps me use them more effectively and understand them better than as a method that lets me do something “after a while”.

The resources I’ve gathered cover a wide amount of information on coroutines. There are details on the terminology used around them with the most technical aspects of how they are made up to small examples on their different uses in Unity scripts. There are also different methods of starting/stopping them covered and how to properly control them.

Complete Beginners Python Tutorial by Programming with Mosh

digm520admin / / Programming, Python, Tutorial
March 11, 2019

Complete Beginners Python Tutorial

Youtube – Complete Python Tutorial for Beginners (2019)

By: Programming with Mosh

I wanted to try using Unity’s ml-agent toolkit and its initial setup uses a lot of Python so I got interested in learning the basics to better navigate the toolkit and its full potential. This was one of the first tutorials I came across and its size and recency made it an attractive choice to cover a lot of ground that shouldn’t be outdated for any reason. Its size is also a bit of a drawback at over 6 hours, so I will most likely break this up and cover it in the upcoming weeks.

Unity ML Agent Setup in Windows

digm520admin / / MachineLearning, Programming, Python, Unity
March 11, 2019

Setting Up Using ML Agents in Unity

Windows 10 Setup

Unity – Machine Learning
Unity – Windows Installation

I was interested in trying out Unity’s machine learning agents toolkit so I started attempting to get everything setup and installed today. I have no prior experience with Python, so that took a bit of getting used to.

I had some trouble setting up initially as I followed the link in the documentation for the Python download which led me to get Python 3.7, but Python 3.6 is what is used in the installation notes. When I went to install the TensorFlow component, I couldn’t get that to work in 3.7. Afterward I went back and got Python 3.6 and setup a 3.6 environment and got the same error initially, but then got it to work after actually activating the ml-agents environment (so I may have been able to solve the error in Python 3.7 with this change).

Otherwise the setup went rather smoothly. The excessive use of Python encouraged me to look into some tutorials to start learning the basics to handle this Unity ml-agent system better.

The Windows installation also included an extra section for getting into GPU training for the ML-Agents. This seems like it adds a lot of extra complications so I am going to stick with the basic setup for now, but I may come back to this once I get a better grasp of Python and the ml-agent toolkit.