Correct size units for prefabs.

Unity Engine
1

Hi, I have some very newbie questions. I’m developing my very first mobile game and I’ve chosen Blender to use with Unity; I’ve seen and read several tutorials and now I have a pretty decent (basic) understanding on how the platforms work together. My game requires the creation of a city street with cars, pedestrians, trees, traffic lights and signs etc. and I’ve seen that everyone recommends to create separate 3D objects for all the elements in the scene and then export them as FBX and create prefabs inside Unity, my questions are:

  1. Regarding the size and measurement units: What’s the best approach to create the 3D models in Blender so they can work properly inside Unity? For example, what’s a good size for a 6 story building? 1 unit per story? Which element you recommend that I should use as the “base size” for my other elements?

  2. My terrain is going to be flat with the possibility of having minor height deformations…Is it better to create my terrain inside Unity or should I make pieces in Blender and export them as prefabs into Unity? Which one is better for mobile development?

Thanks in advance.

2

Unity uses 1 unit = 1 meter measurements.

3

Not necessarily, that’s just a general guideline. In this case it’s a good answer, but for other people viewing this thread:

1 unit can be whatever you want it to be. 1mm, 1m, 1km, whatever works best for your game. If, for example, the game was about planet travel you certainly wouldn’t want 1 unit to be 1 meter, as floating point numbers can’t hold nearly high enough values for the distances between planets. The same goes for ant-sized games; you can only get so many digits after the decimal.

4

This is the same for Blender. By default, Blender units are completely arbitrary. 1 Blender Unit becomes 1 Unity Unit (if you make sure that the export and import steps are not performing extra scale transformations). In Blender, you can inform the app that you would like 1 Blender Unit to be one meter or one foot or whatever else you like, and it will show the units in all measurement fields in the interface. But they’re still just a number.

I’m currently working on a set of assets that use a historically significant measuring system that is neither metric nor imperial. It’s kind of interesting to do this. However, if I offered the assets for sale in the Unity Store, I would scale them to match 1 unit = 1 meter, as a matter of convention and compatibility with other assets.

5

Thanks, so I guess I’ll make some tests and use what I feel most comfortable with.