How can I create a 2D large-scale planet generator?

I am currently working on a game where you are able to own your own space program and create crafts to launch into space. I have the gravity system fully implemented although I cannot find a good way to generate the planet mesh with a high-resolution collider. I have tried to create it out of triangles using a mesh generator but that created a lot of performance issues and I was unable to get the collider to work. Any ideas on how I could solve this problem would be highly appreciated. Thank you.

P.S. I am quite new to Unity and have only been coding in it for about 18 months.

Everything done “large” is best first done “small” until it works perfectly.

If you contemplate something so large that handling it all at once is impractical, then some kind of chunking scheme that breaks it into smaller sub-parts, coupled with logic to only consider the “active” or close parts is likely going to be the direction you want to look.

Otherwise…

Figure out what that means in a way you can fix. This template could prove helpful:

How to report your problem productively in the Unity3D forums:

http://plbm.com/?p=220

This is the bare minimum of information to report:

  • what you want
  • what you tried
  • what you expected to happen
  • what actually happened, log output, variable values, and especially any errors you see
  • links to documentation you used to cross-check your work (CRITICAL!!!)

The purpose of YOU providing links is to make our job easier, while simultaneously showing us that you actually put effort into the process. If you haven’t put effort into finding the documentation, why should we bother putting effort into replying?

If you have absolutely no idea what is happening, FIX THAT FIRST. Here’s how:

Time to start debugging! Here is how you can begin your exciting new debugging adventures:

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

Once you understand what the problem is, you may begin to reason about a solution to the problem.

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 names of the GameObjects or Components involved?
  • 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 supply a second argument to Debug.Log() and when you click the message, it will highlight the object in scene, such as Debug.Log("Problem!",this);

If your problem would benefit from in-scene or in-game visualization, Debug.DrawRay() or Debug.DrawLine() can help you visualize things like rays (used in raycasting) or distances.

You can also call Debug.Break() to pause the Editor when certain interesting pieces of code run, and then study the scene manually, looking for all the parts, where they are, what scripts are on them, etc.

You can also call GameObject.CreatePrimitive() to emplace debug-marker-ish objects in the scene at runtime.

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

Visit Google for how to see console output from builds. If you are running a mobile device you can also view the console output. Google for how on your particular mobile target, such as this answer for iOS: https://discussions.unity.com/t/700551 or this answer for Android: https://discussions.unity.com/t/699654

If you are working in VR, it might be useful to make your on onscreen log output, or integrate one from the asset store, so you can see what is happening as you operate your software.

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.

If your problem is with OnCollision-type functions, print the name of what is passed in!

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://discussions.unity.com/t/839300/3

If you are looking for how to attach an actual debugger to Unity: https://docs.unity3d.com/2021.1/Documentation/Manual/ManagedCodeDebugging.html

“When in doubt, print it out!™” - Kurt Dekker (and many others)

Note: the print() function is an alias for Debug.Log() provided by the MonoBehaviour class.

My recommendation would be to try different colliders.

If you can express the planet as the points of an arbitrary polygon, you probably want a PolygonCollider2D.

If you want to have more of a grid-based system, where you have very formulaic building blocks for a planet, try a TilemapCollider2D with CompositeCollider2D. You might consider hexagonal tiles to build up a planet.

These are the two main options imo.

You need to provide more information. It’s unclear what the “performance issues” were here. In your scripts or were you saying it was somehow physics which could only be because you were adding way too many shapes and potentially moving it. It’s unclear here what you mean by large-scale planet generator; sounds like terrain to me. The fact it’s a “planet” in that case would be the game story, not the dev.

If you only need a surface (no idea) then only model the surface with a single or multiple EdgeCollider2D.

Basically need more info if you do want help.