I know the unit in Blender are arbitrary, e.g. you can have one unit represent 1cm, 1ft or 1 mile.
I'd like to know if there's an advised (community or otherwise) scale that I should work to.
Are there any issues that might occur from basing your scale too high or too low. e.g. 1 unit = 1mm or 1 unit = 1km?


I know that many of them struggle with precision issues because of large scenes which have a huge contrast between what is really big and what is really small. <- like shadow map resolution compared to the size of a mountain chain; So if you have some things like mountains with numbers like 1000000.0 units. And then there are shadows with small numbers like .00001; once you perform math operations that combine these numbers, the smaller numbers can be damaged(loss of precision.
– MarcClintDion Oct 24 '14 at 01:12