# UE5 how to tell the size of your map in km.

I’m trying to generate a terrain for an 8km x 8km map in Unreal. I’ve used World Machine to give me the terrain but it does not look like it is 8x8 at all despite specifying 8x8 in World Machine. How can I tell how many km x km my map is in Unreal?

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Top view, when you zoom out

This eluded me for a long time. It’s based on Resolution * Scale.
A map with a resolution of 2048 * 100 scale = 204800cm = 2.048km.

So any of these = 8x8km:
2048 * 400 scale
4096 * 200
8192 * 100

Also in Top-View, dragging middle-mouse will act like a ruler, showing cm. (100,000 = 1km)

World Machine may be scaling for 8km world but if you output a 2k image, it has to be scaled up 400x to actually be 8km. It’s a mind bender.

Why is it a mind bender?
100% of 1024 is 1024.
200% is 2048
300% is 4096
400% is ???

Anyway. Using textures above 1k for landscapes is a recipie for 10fps if even…

And another thing
1m^2=1pixel of heightmap

It looks like there’s a misunderstanding in the progression of the numbers provided. Here’s the correct calculation:

• 100% of 1024 is indeed 1024.
• 200% of 1024 is 1024 * 2 = 2048.
• 300% of 1024 is 1024 * 3 = 3072 (not 4096 as mentioned).
• Therefore, 400% of 1024 would be 1024 * 4 = 4096.

The error in your statement was the value provided for 300% of 1024. It should be 3072 instead of 4096.

just like 200% of 100 is 200,
300% of 100 = 300 ( not 100x100x100 ) xD

You know there is a forumla in the documentation for this?

Width and Height

(meters * 100) / resolution

There are also very specific resolutions you should be using.

1024 is NOT a valid resolution for a height map 1009 is.

All the information is detailed here

Therefore if you have an 8K resolution map which is an 8129x8129 resolution height map. And you want your terrain to be 8Km squared

The formula is 8000 * 100 / 8129 or 800000/8129 or 98.413088940 scale

There is also a formula for the height which is

(meters * 100) / 512 the 512 is the maximum resolution for the height.

You can use the middle mouse button in the top view, pull from one side to the other by pressing the middle mouse button, and measure the distance in centimeters

512 is not a maximum resolution for anything.

The height value of a heightmap is infinite.
You can set the z scale to whatever you want.

The end result is 1/65535 * resolution you picked = vertical distance between pixels of different colors in heightmap.
(Uu or centimeters I think).

If there really is bad verbiage stating a limit on height factor in the docs, then everyone should be filing a complaint with the doc editors for yet again writing bad documentation.