If you will indulge me for a few minutes

I am looking for a 1:1 earth model that I can build a 5x 5 tile for terrain, city planning etc.

I want to build on a planet surface that I can put mechanisms onto. Driving etc etc. Shooting.

Can people direct me to the asset that I must be blind from so many options I just can’t see.

I’m not afraid of a few quid! £100 +.

I want a full sized earth. no sky, clouds and such. Just land mass I can import on to from other assets. So in other words if I put a character on. It will walk up Mount Everest. You get my meaning.

I imagine a wire mesh frame with tonnes of triangles and a fair hefty file size,

I’m not looking for a world view terrain builder, a nice spinning earth etc etc. I want to build on any area I choose which is to be 5kmx 5km in size per tile.

But has to be the dimensions of earth or as close as reasonaby possible.

Please help. Geuine need. And willing to pay for a real useable and thus I own the product to what I want to do with; where I can have some fun with building some crazy concept.

It needs to be on size with land masses, no funky water mechanic. But water outine is helpful.

Thank you in advance for any support you can offer a dreamer!

You can surely make a simple sphere and give it a radius of 6371000 meters. But that kind of model is not going to work well with Unity cameras or pretty much any computer modeling system. The problem is the accuracy of numbers, or more specifically their precision.

An optional lesson on floating point precision.

The default float value on Unity is a 32-bit IEEE754 variable. It can represent numbers from 0.0 all the way up to
3.402823466*10^38 (or about 300 Undecillion, a 3 followed by 38 zeros), or a negative value in the same range. It can even represent tiny values, like 1.175494351e-38F (or about 1 Undecillionth).

HOWEVER, this magical 32-bit float variable cannot represent every possible number in that range. Just like a tape measure or ruler on your desk, there are only so many “marks” or possible places you can measure with this value, with some empty space between the marks. Unlike a tape measure, the marks change their spacing as you get closer to 0.0. When you’re really close to 0.0, the marks are very close together. When you’re really far from the origin, the marks get farther and farther apart. Also unlike the tape measure on your desk, you can’t actually have any values other than the marks given.

If you give a value of 6371000 meters, for the radius of the Earth, and you put a 1 meter cube on its surface, it can only approximate the location of the vertices of that cube, according to the marks on that IEEE754 “tape measure”, and the finest marks you can get at that range is 0.5 meters! So each corner of that cube may collapse or nearly double your intended size. Moving the cube around, it must clunk around in 0.5 meter increments.

The clipping planes on cameras is similar: the higher the ratio is between “far” clipping plane and “near” clipping plane, the worse your Z-fighting and Z-confusion resolution will get. To be able to distinguish nearly-parallel elements like windows from walls and doors and signs at 4 kilometers away, you would need a near clipping plane that is a meter away from your camera.

The practical upshot of all this.

All of game design and game development (and computing in general) revolves around verisimilitude. You have to approximate, you have to pick and choose your battles, you have to select what needs to be real and fake the rest. You need to load just the terrain you could see, and other users in the same online world may be loading an entirely different chunk of terrain. As you transition from area to area, you need to unload what you can no longer see, so you have space to load more important elements.

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Wow that’s what Holyfield felt like!

Genuinely thank you sir. That is truly epic of you. I understand exactly what you mean despite no knowledge, as in I can see the problem as you put it.

I am presumptuous in such a way that in next couple years, cpu / Gpu will be able to handle more n more. . However don’t think me la Di la dreaming… I understand that it is likely near impossible.

But I am hopeful of creating areas where if ‘player’ has 5x5km vision max and buildings are static… ie. non procedural buildings… but inside selected buildings… “populate”.
If no player within 100km Sq. “Do not generate terrain”
Is this possible?

I’m not necessarily looking for New York depth
But more ye olde England! At least to start…
again am I dreaming here.

Would you expect it to be better to make maps of countries and then put them on a flat plane for example?

Any devs? Looking for a challenge. Quote me a price. Please consider me as a hobbyist not some crazy millionaire as I assure you I am not… so if it would require so much time, I would also appreciate your analysis of the expected cost so I can guesstimate true costs…

Thank you

Shameless plug coming up… but I’m currently developing CityGen3D which is a Unity asset that automatically creates a 3D environment based on a real world location.

You are able to generate Unity scenes from any position in the world, as it downloads the map data for you based on the location you specify.
So for example, if you were creating a driving game and wanted levels in London, New York and Singapore, you could use CityGen3D to create each of these scenes for your game.

Not sure if it’s exactly what you are looking for, but thought I’d mention it in case it was of interest as I’m hoping to have a beta available in a few months.

Here’s a rendering of Gibraltar to give you an idea of the type of thing it can do.
I have more closeup screenshots on twitter @CityGen3D .

I also have a thread on the Work In Progress forum if you are interested in following development: [RELEASED] CityGen3D | Procedural city generation from map data

Either way, good luck with your project!

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