A map the size of Eurasia

Hi all,
New to these forums and to Unreal engine in general. As you can tell by the title, I’m insane, and far too ambitious for my own good, Lol. I have a project in mind to build out my homebrew fantasy world on a 1:1 scale in UE4. This is not intended for multiplayer or for any actual singleplayer game really. I just want to walk around my creation. While I’m building the continent in world machine I’ve been trying to research if it’s feasible to get the whole thing in there at once or if I’ll have to settle for cutting it up into a lot of different project files. I’ve seen that it’s “theoretically” possible to build as large a map as I want using world composition, origin shifting, etc. I haven’t seen an answer though on whether this is actually realistically possible given that I don’t have a ten thousand dollar super computer.

So I’m asking if my ambitions need to be reeled in here (I’m guessing they probably do). I imagine even with world comp and other things to help lighten the load it still must be taxing to load even a 1/10th of what I’m going for. So what are some examples of some of the largest maps made and how taxing is it on the hardware? Even if it is possible, can the maps be populated with plants and buildings, etc. with nice shaders and stuff at this size? Or does a map this size need to essentially be empty to even load?

What I’d like to do to start with is a map roughly 10x10 km and maybe build out from there. So my other question is, can I swap out maps in the same UE4 project as I detail more areas of my game world in world machine? Say I import the map from world machine begin to populate it with buildings and decide later to change rivers or mountains or detail surrounding areas, can I pop that new map (or adjoining maps using world comp. and grow the map as I go) in place of the old one and keep all the things?

On a technical level, there’s not really a limit. Not everything gets loaded at once, you really only need 9 sections at once (the one your’e on and the ones surrounding it) So the rest aren’t loaded until you get close enough.
But, there are other limitations, in that you wouldn’t be able to generate a height map big enough, and you’d use too much storage space.
Also, there’s no point, unless you can fill the map with interesting things to see/do then why bother

Well like I said it’s only meant for my own personal enjoyment to fill at my leisure so I don’t mind if it’s boring. I just wanted to know what is practically possible not theoretically.

With world composition, is it possible for me to load in my map at piecemeal 10x10 km at a time?

For physics, the limit is around 6km, so for safety it’d be good to do it in 5kmx5km pieces.
Beyond a certain point, the numbers become too big to have a high enough precision (due to the kind of variable that the values get stored as) and so things like movement and physics have problems. That’s why there’s world composition and origin shifting, where it moves you back to 0,0,0 so that the numbers are low again.

Thanks for the reply. I do realize that this is really too ambitious, so thats why I’m interested in learning the practical restrictions

According to this Wikipedia article, Eurasia covers a land area of around 55,000,000 square kilometres (21,000,000 sq mi).

Even if your height markers were 10 metres apart, that would still use up a lot of drive space, so that’s one restriction.

Another is time. I would be surprised if one person could walk all over that large an area in a single lifetime, even if it were flat and free of obstructions. Daggerfall has an area of about 161,600 square kilometres, and according to the developers it takes about two weeks (real time) to walk from one side of the map to the other.

Lol I know. I have no doubt I’ll probably end up never detail more than .0001% of a map that size. I’m here just asking if its actually possible to have a map that big without completely blowing up my computer just trying to open it! I’m just taking stock of what my options are. Again, my goal is to just be able to walk around it myself and look at how pretty I can make it. I’m not concerned with making a multiplayer game or even a singleplayer game, just a map to walk around and see how much of this house I can decorate. So I’m just seeing if its possible to do if you strip out those gameplay elements to worry about

I don’t know of anyone that has created a land-based game with a map anywhere near this size, but in theory the world composition and map streaming tools should allow a landscape composed of 16000 5x5 km pieces to be as efficient with memory and CPU as one composed of 16 5x5 km pieces, as only the parts the player can see are loaded at any one time.

If I were attempting this, I’d choose a smaller isolated area on the map - something like the United Kingdom or even the Isle of Wight - and work on that first to get a better idea of how much time, effort and disk space the full map would need. I would then expand from there if I thought I could create the remaining area within my lifetime (and drive space limits) or scale things down if I didn’t.

In terms of feasibility, I would try to make a sRGB bitmap that would store per-landscape-section data in each pixel. Height, materials, vegetation, atmosphere per pixel. Then come up with a way for each landscape section to stitch together, and generate more specific landscape details, like rock outcrops and cliff faces (based on the bitmap). Ultimately, it comes down to letting code generate the map for you based on some predefined parameters. Then maybe you can take that generation and sculpt your own touches into it. Would definitely be a project that starts out small.

Ambitious idea like this requires another ambitious idea to it;
Day/night cycle has been in games forever. Thats no big deal. But your game will have seasonal cycles too! :smiley: The foliage will turn into dying leaves at fall, and barren lands during winter. At spring they will start to bloom again. Lol. You can do that to work real time with real world too, just have the game check global time at every launch so that the date inside game world is same as in real world. That would be something.

Heck,now that I think about it I am actually curious to try this idea myself, for my much smaller game.

I definitely intend to start small. At first I want to maybe two towns and surrounding courtysides and link them together. I’ll move out from there after that. The seasons would be a cool touch, but I’ll cross that bridge if I ever get to it:)