You could ask me why we need this?
Just imagine you have a task where you need to create meshes with high precision. It could be anything: houses, walls, windows, doors, pictures, office facilities – in general everything… So how I did this?

What I am going to say firstly that it‘s very helpful to use following assets Mesh Maker and zzRuler.

Let’s imagine that our task is creating the wall with two boxes. With sizes:
Wall: width: 800 cm ✕ height: 400 cm ✕ deep: 30 cm
Box big: width: 160 cm ✕ height: 90 cm ✕ deep: 160 cm
Box small: width: 120 cm ✕ height: 60 cm ✕ deep: 120 cm

Unity always measures all objects in meters and if you have different units it would be good to convert them at once.

For example this is the meter conversion of our wall and box sizes :
800 cm ✕ 400 cm ✕ 30 cm = 5m ✕ 2m ✕ 0.3m
160 cm ✕ 90 cm ✕ 160 cm = 1.6m ✕ 0.9m ✕ 1.6m
120 cm ✕ 60 cm ✕ 120 cm = 1.2m ✕ 0.6m ✕ 1.2m

Step 1 – install zzRuler, Mesh Maker assets.

Please pay attention that zzRuler is free asset but Mesh Maker isn’t. You can trust me that Mesh Maker is a good investment. It helped me a lot in everyday dev.

Step 2 – put rulers into your scene.

In folder zzRuler you can find two ruler prefabs: horizontal and vertical. I highlighted them on the screenshot below.
ruler_folder

Currently, we need both of them. Moreover, we need 1 vertical and 2 horizontal rulers to measure height (y), width (x) and deep (z). Just drag them on Hierarchy Panel.

It should look like this😏 to measure all at once.rulers

Step 3 – create the wall

Put a cube on your scene, it will be our future wall. Please resize by using the ruler 1 x 1 x 1.
resize1_1_1

Then check the scale values in Inspector.
Don’t worry, if they don’t fit into the rulers’ one. Use Mesh Maker to reset the scale to 1:1:1.
To do this you should go Window → MeshMaker → Mesh Editor. Click the button Lock and save the mesh, let’s call it “wall”. Then just click the button Normalize and all scales will be reset to the 1:1:1.

mesh_editor
Now your object is ready to be resized.

Step 4 – resize to appropriate sizes

Since now we have the scale 1m:1m:1m, we need to change wall’s scale to the appropriate size in meters 8m ✕ 4m ✕ 0.3m.
scale Below you can see the result.
deep

width_height

Step 5 – measure and resize Boxes

All of these steps you should repeat with boxes.
This is my final result with highly precise boxes and wall yay!
final

The full sample you can find here

I hope this article is useful in some way 🙂 and maybe can save a huge amount of time. If you have some questions, concerns or suggestions feel free to contact me or comment here.