Bird flying backwards in Angry Birds Like Game Tutorial (Terrible Tweeters YouTube Tutorial)

[Kurt-Dekker]

There’s many ways this could break… have you been working with backups? If so, revert to before you did whatever change that broke it. If not, you have to do these steps:

1. figure out what actually causes the bird to fly (eg, trace the numeric data from finger-drag through to fling). This might involve adding pieces of code to print stuff out. See the very bottom of this post.

2. reason about why it is wrong

3. fix it

Generally, this all falls under Step #2 of my “Two Steps To Do Tutorials Properly” guide. Let me offer you the guide here:

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Tutorials and example code are great, but keep this in mind to maximize your success and minimize your frustration:

How to do tutorials properly, two (2) simple steps to success:

Tutorials are a GREAT idea. Tutorials should be used this way:

Step 1. Follow the tutorial and do every single step of the tutorial 100% precisely the way it is shown. Even the slightest deviation (even a single character!) generally ends in disaster. That’s how software engineering works. Every step must be taken, every single letter must be spelled, capitalized, punctuated and spaced (or not spaced) properly, literally NOTHING can be omitted or skipped.

Fortunately this is the easiest part to get right: Be a robot. Don’t make any mistakes.
BE PERFECT IN EVERYTHING YOU DO HERE!!

If you get any errors, learn how to read the error code and fix your error. Google is your friend here. Do NOT continue until you fix your error. Your error will probably be somewhere near the parenthesis numbers (line and character position) in the file. It is almost CERTAINLY your typo causing the error, so look again and fix it.

Step 2. Go back and work through every part of the tutorial again, and this time explain it to your doggie. See how I am doing that in my avatar picture? If you have no dog, explain it to your house plant. If you are unable to explain any part of it, STOP. DO NOT PROCEED. Now go learn how that part works. Read the documentation on the functions involved. Go back to the tutorial and try to figure out WHY they did that. This is the part that takes a LOT of time when you are new. It might take days or weeks to work through a single 5-minute tutorial. Stick with it. You will learn.

Step 2 is the part everybody seems to miss. Without Step 2 you are simply a code-typing monkey and outside of the specific tutorial you did, you will be completely lost. If you want to learn, you MUST do Step 2.

Of course, all this presupposes no errors in the tutorial. For certain tutorial makers (like Unity, Brackeys, Imphenzia, Sebastian Lague) this is usually the case. For some other less-well-known content creators, this is less true. Read the comments on the video: did anyone have issues like you did? If there’s an error, you will NEVER be the first guy to find it.

Beyond that, Step 3, 4, 5 and 6 become easy because you already understand!

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As far as working and keeping regular “step by step” backups, please consider using proper industrial-grade source control in order to guard and protect your hard-earned work.

Personally I use git (completely outside of Unity) because it is free and there are tons of tutorials out there to help you set it up as well as free places to host your repo (BitBucket, Github, Gitlab, etc.).

You can also push git repositories to other drives: thumb drives, USB drives, network drives, etc., effectively putting a complete copy of the repository there.

As far as configuring Unity to play nice with git, keep this in mind:

Prefab links keep getting dumped on Git pull

There really isn’t any fix because git works perfectly with Unity when configured properly. Best practices involve saving your work and closing Unity before using git. But if you understand how Unity does and does not flush changes to disk (or at least ALWAYS do a save-project), you can get away with leaving Unity open. The only thing linking EVERYTHING together in Unity is the GUID assigned to a script or asset. Name is irrelevant. Only the GUID connects it. This GUID is in the meta file. I…

Here’s how I use git in one of my games, Jetpack Kurt:

2 steps backwards

Yeah, what Praetor said is it… Debug.Log is your friend, and also since this is animation related, you can open up the Animator window when you expect the animations to go, and actually visually see where the state machine is, see which state it thinks it is in. You can combine this with Debug.Log() output at the locations where you set the animations to be what you think they should be, and that should lead you to some intel. I highly recommend setting up git source control. It really plays ni…

Using fine-grained source control as you work to refine your engineering:

When to make a separate object or class/script? Help me think like a programmer! (Example in text.)

This is a reasonable initial approach. The problem is you have listed the parts, but you haven’t really listed how they interact, and even if you did, it’s still sorta up to you how to organize it. Only YOU will know how to organize it, and the only way you can tell is to do the work. I recommend this: first, develop ALWAYS with source control (such as git), and every time you get even the slightest thing working, commit those changes with good commit messages. Then move to the next thing, c…

Share/Sharing source code between projects:

Your techniques to share code between projects?

I have found that bundling your own code into DLLs only serves to slow down your workflow. I base this on several years of experience dealing with other teams well-intentioned packaging mishaps. With games, it is almost always useful to reach into library code, make a temporary tweak to isolate a problem, and then revert it. With DLLs this is impossible, making workflow harder and more brittle. I prefer to share source code at the C# level. That way I can reach into libraries trivially and inje…

Setting up an appropriate .gitignore file for Unity3D:

Removing IL2CPP_cache from Project

Not sure what you are “auto generating” with… I usually start from one of my other projects, or a gitignore example online, and reason about all the parts inside it, and start from there. Like any other configuration change, after you make it, pay attention for a while to make sure it is what you want. You can always clone the repo somewhere else to verify that the correct files are being tracked. Doing so to a brand-new computer is the acid test to make sure you can still build the project. …

Generally setting Unity up (includes above .gitignore concepts):

How to Git with Unity

It is only simple economics that you must expend as much effort into backing it up as you feel the work is worth in the first place.

“Use source control or you will be really sad sooner or later.” - StarManta on the Unity3D forum boards

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Whatever is happening, you must find a way to get the information you need in order to reason about what the problem is.

What is often happening in these cases is one of the following:

• the code you think is executing is not actually executing at all
• the code is executing far EARLIER or LATER than you think
• the code is executing far LESS OFTEN than you think
• the code is executing far MORE OFTEN than you think
• the code is executing on another GameObject than you think it is

To help gain more insight into your problem, I recommend liberally sprinkling Debug.Log() statements through your code to display information in realtime.

Doing this should help you answer these types of questions:

• is this code even running? which parts are running? how often does it run? what order does it run in?
• what are the values of the variables involved? Are they initialized? Are the values reasonable?
• are you meeting ALL the requirements to receive callbacks such as triggers / colliders (review the documentation)

Knowing this information will help you reason about the behavior you are seeing.

You can also put in Debug.Break() to pause the Editor when certain interesting pieces of code run, and then study the scene

You could also just display various important quantities in UI Text elements to watch them change as you play the game.

If you are running a mobile device you can also view the console output. Google for how on your particular mobile target.

Another useful approach is to temporarily strip out everything besides what is necessary to prove your issue. This can simplify and isolate compounding effects of other items in your scene or prefab.

Here’s an example of putting in a laser-focused Debug.Log() and how that can save you a TON of time wallowing around speculating what might be going wrong:

Coroutine missing hint and error

This is so unnecessary. Use the beauty and power of instantly and immediately putting a Debug.Log() statement into the very start of the coroutine, right at the top. Do this always at the very first sign of trouble or question in your mind. The instant you did this you would see “Oh man, this code is simply not getting run!” And you could LASER-FOCUS 100% your efforts on studying what you expect to run it, eg., the call location, and isolate why it is not running. You would look at literall…