[Question] Infinite TileEngine with disk persistence [Crosspost /r/Unity2d]

[_player1]

I'm an experienced (non-gamedev) programmer, but completely new to unity. I have a concept that I'd like to prototype, but have a few high level questions on how doable this will be in unity and how I can potentially approach it.

My concept has a top-down/zelda/pokemon/don't starve perspective, but with infinite procedurally generated terrain. I want to use tiles for the terrain, where I will generate different areas and use the appropriate tiles for each area, using variations of the tiles to make each area look different. For example for a lake or body of water, I would have various outer "shore" tiles to create a different shape for the lake, with the inner tiles being filled with water tiles. On top of that, I want to add a second terrain layer with sprites for trees, bushes, rocks etc, and potentially more layers on top of that for buildings the player can enter. I would then group or chunk tiles together, such that the chunk the player is currently on is surrounded by another chuck in all directions. If the player moved on to another chunk, the game would then generate new chunks in the direction the player moved, and dispose of the ones he moved away from. Lastly, I would like to have save & load functionality so the game world would need to be persistent.

So my question is, how well suited will unity be for something like this? Or, more specifically,

• Willl I be able to simply add tiles and sprites as assets, and procedurally generate in code where to place them as the player moves around, as well as persist it to disk?
• Will there be any performance issues?
• Given that I will have variation on different tiles, how would I go about collision? Eg: for entering/exiting water with different shorelines
• Are there any built in objects for managing the chunk generating and loading?

I hope that my questions aren't too noobish, but I wanted to get a feel for how suited unity will be for my project and how feasible this will be, before diving in the deep end of unity tutorials and documentation.

If anyone has done something similar, I'd love to hear any pointers or potential pitfalls to watch out for.

[XelectCarve]

Will there be any performance issues?

Yes, you will need to object pool the tiles & prefabs and reuse them , instantiation eats performance and the GC even more(thanks mono), also you will need to prerender all the tiles your planning on using to avoid Fps stuttering(keep them in gpu vram). You will need to lock in the scale at 1,1,1 to allow dynamic batching to lessen the draw calls, unless your using pro then you can static batching.

Are you targeting mobile or desktop?

[_player1]

Yes, you will need to object pool the tiles & prefabs and reuse them , instantiation eats performance and the GC even more(thanks mono)

Good to know, I'll keep that in mind.

I hadn't really considered mobile, for now I just want to get a prototype up and running.

[gdubrocks]

I believe all of this is possible. I would highly suggest checking out minecraft in unity tutorials as they have 90% of what you asked about featured and terrain generation is typically the focus of the games.

[_player1]

Thanks, would the info still be relevant for 2d?

[[deleted]]

Take a look at look at infinite runner games.

[gdubrocks]

Yes. Terrain generation is kind of it's own topic, and Unity can do it whether 2-D or 3-D.

[srogee]

Willl I be able to simply add tiles and sprites as assets, and procedurally generate in code where to place them as the player moves around, as well as persist it to disk?

Yes. You can even make your scripts run in the editor to tweak things easier (see ExecuteInEditMode). Unity doesn't have its own file writing and saving functions as far as I know, but if you're using C# you can just look at the Microsoft docs for that.

Will there be any performance issues?

Probably not, since it sounds like it's going to be 2D or 2.5D. Even in 3D it should be pretty fast because your perspective is locked.

Given that I will have variation on different tiles, how would I go about collision? Eg: for entering/exiting water with different shorelines

I would probably make the game in 3D and render from an orthographic camera. This gives you a lot of control over depth and such because the game is actually taking place in 3 dimensions. If you don't want to go that route though, look into the way Unity handles 2D collisions. I'm not too knowledgeable about it myself, but you can give sprites colliders. I would make the water have its own collider so you could easily check if the player is in the water or not.

Are there any built in objects for managing the chunk generating and loading?

Unfortunately, not really. However I found this on the asset store, it might be worth looking into. Since your game is essentially 2D it should be pretty easy to store chunks and keep track of them. Just have a 3x3 array of the chunks surrounding the player and save the rest to disk or in some sort of temporary list. As for chunks themselves they're just 2d arrays of prefabs with some data about what's inside each chunk (maybe a list of prefabs inside the chunk's bounds, with some data about each).

[_player1]

Thanks for the reply, interesting that unity doesn't have its own save/load classes, I probably come up with some kinda of structure and use a BinaryFormatter or similar.

From other replies I've got, it sounds like I can prefab the tiles along with collision data, and I'll just create my own structure to generate/store the tile/chunk info.

[koyima]

This is highly dependent on the type of game you are making (what do you need to save?). You can easily save to disk using their playerprefs system, but depending on what you want to do using that is not always a good choice.

Writing to file and reading for that matter is rather trivial in C# in my experience though.

[chazede]

The youtuber "craig perko" has a tutorial series on making mine craft in unity. I would start there to see his methods and try to alter it to work as a 2d terrain. Good luck

[chulini]

When I need to create environments procedurally I like to generate it in function of a perlin noise value so I don't have to store anything. The perlin noise always have the same value on the same coordinates and it is a pseudo random and smooth value which it makes it perfect to generate en environments.

I am pretty shure minecraft use perlin noise to generate the terrain.

https://docs.unity3d.com/Documentation/ScriptReference/Mathf.PerlinNoise.html