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How to trigger a particle system with a collision?

Discussion in 'Editor & General Support' started by vituba2202, Jan 19, 2022.

  1. vituba2202

    vituba2202

    Joined:
    Jun 8, 2021
    Posts:
    13
    I'm making a game and I want to make it so that while the player is in contact with a water surface, a particle system activates and remains active until they leave the water surface. How can I go about implementing that?
     
  2. Kurt-Dekker

    Kurt-Dekker

    Joined:
    Mar 16, 2013
    Posts:
    38,519
    Screen Shot 2022-01-19 at 7.01.16 AM.png
     
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  3. vituba2202

    vituba2202

    Joined:
    Jun 8, 2021
    Posts:
    13
    I've seen this tutorial already (It's great btw), but I can't seem to get it to work in my 3D game
     
  4. Kurt-Dekker

    Kurt-Dekker

    Joined:
    Mar 16, 2013
    Posts:
    38,519
    We know it is possible to do this, so now you have to debug to find what you are doing wrong.

    Obviously nobody here knows what is happening when you run the above code. Could be code, could be setup, could be anything.

    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
    - you're getting an error or warning and you haven't noticed it in the console window

    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:

    https://forum.unity.com/threads/coroutine-missing-hint-and-error.1103197/#post-7100494

    It's also possible you are not doing tutorials properly.

    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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  5. vituba2202

    vituba2202

    Joined:
    Jun 8, 2021
    Posts:
    13
    I'm sorry I took a while to aswer but thanks for your great (and extensive) responce! I'm still not sure what was causing it to not work initially but I've remade the entire system and after a few tweaks I've gotten it to work! Thanks!