GameMaker Crash: Particle System Bug Explained And Fixed

Hey guys, have you ever run into a weird crash in GameMaker? Specifically, one that seems to come out of nowhere when you're working with particle systems? Well, you're not alone! This article dives deep into a frustrating bug where calling particle_get_info() or part_system_get_info() on a particle system created in code, and then adding its first emitter also through code, causes a silent crash. Let's break down this issue, explore how to reproduce it, and figure out a workaround to keep your projects running smoothly. Get ready to explore the intricacies of GameMaker's particle system and how to navigate this particular hiccup!

Understanding the Core Issue: The Particle System Bug

Let's start with the basics, shall we? The core problem lies in the way GameMaker handles particle systems when they're created and initialized entirely through code. Specifically, the bug triggers when you create a particle system, and then immediately add an emitter to it, all within your code. When you then try to retrieve information about this system using either particle_get_info() or part_system_get_info(), boom! Your game crashes silently. There is no error message, no warning – just a sudden end to your game. This is a classic example of a frustrating and hard-to-debug issue.

This bug essentially throws a wrench into the process of dynamically setting up particle systems, which is a common requirement in many games. Imagine a game where you need to spawn different particle effects based on player actions, enemy types, or environmental conditions. You need a way to create and manage these systems on the fly, but this bug makes that more difficult, and in some cases, impossible. It's a situation that can stop you from easily accessing and understanding the structure of your particles. It means your ability to debug and maintain your particle effects is severely impacted.

This bug is specifically associated with the initial creation of an emitter on a particle system. This means that you're unable to add the very first emitter programmatically after its creation. In more technical terms, the system seems to have issues with its internal initialization when the first emitter is added through code, which causes a fatal error during information retrieval. It affects the ability to properly access particle data.

Now, let's look at the code that causes the issue. The following code snippet showcases exactly how the crash happens. Understanding this is key to understanding the root of the problem and how to avoid it. This will illustrate precisely what triggers the problem and what can be done to prevent it from rearing its ugly head in your projects. It is also important to note the versions of GameMaker this impacts, so that developers can understand if their project is safe.

// Crash example
ps = part_system_create();
info = particle_get_info(ps); // Executes fine
show_debug_message(json_stringify(info, true)); // "emitters" value is shown to be 0.0, though should be an empty array

pe = part_emitter_create(ps);

info = particle_get_info(ps); // Fatal error
show_debug_message(json_stringify(info, true));

Reproducing the Crash: Steps to Trigger the Bug

Reproducing the bug is incredibly easy, which is both a blessing and a curse. It's simple to identify, but it's also a significant stumbling block if you're unaware of its existence. Here's how you can reliably recreate the crash:

1. Start GameMaker: Open your GameMaker IDE. Make sure you're using a version that's known to be affected (v2024.13.1 or v2024.1400 betas). This is an important step, as different versions might have varying behaviors. Keep your version in mind during development.
2. Create a New Project or Open a Sample: You can either start a fresh project or use an existing one to test this. For simplicity, a new project is the easiest route. This will isolate the code and make the bug easier to focus on.
3. Add the Code: Insert the buggy code snippet shown above into your GameMaker project. A good place to start is the 'Create' event of an object in your game. This makes the particle system creation and information retrieval happen when the game starts or when a specific event is triggered.
4. Run the Project: Run your GameMaker project. You should immediately experience a silent crash. There will be no error messages in the output, making it a classic example of a difficult debugging problem. This is where it becomes clear that something went wrong.
5. Analyze the Code (Optional): If you're curious, you can use the debugger to trace what is happening just before the crash. However, you will likely see that the crash occurs when calling either particle_get_info() or part_system_get_info() after creating your first emitter programmatically.

If you follow these steps, you should be able to reproduce the crash consistently. The consistent nature of the crash means it is extremely reliable, once identified.

Workarounds: Bypassing the Bug and Getting Things Done

While the bug exists, there are methods to circumvent it and proceed with your project. Here are a few workarounds to consider:

1. Using Particle System Assets

The easiest workaround is to leverage particle system assets within your GameMaker project. If you create a particle system asset within the IDE (which includes at least one emitter), you can then use this asset when you create your particle system through code. This ensures that the internal setup of the particle system is initialized correctly and avoids the crash.

Here's how you would use this method:

1. Create a Particle System Asset: In your GameMaker IDE, create a particle system asset. Make sure the asset includes at least one emitter configured. The mere presence of an emitter in the asset is what fixes the issue.
2. Modify Your Code: When you create your particle system through code, instead of calling part_system_create() with no arguments, pass the asset to the function. For instance: ps = part_system_create(my_particle_system_asset);.
3. Continue with your project with the now created and pre-initialized particle system.

This approach resolves the crash because it ensures that the particle system is set up properly when it is first created. The act of defining an emitter in the asset seems to