Terrain - Best Technique To Show Precise Surface Details?

Just looking for technique advice:

I’m building a driving simulator for a large warehouse complex, nearly 3 miles by 3 miles in size. Its surface (i.e., ground) details must show sharply and clearly, including painted markings, painted signage, painted lines, walkways, and roadways (all different).

Question: is it best to 1) build many mid-sized terrains, butted-against eachother, each with its own high-res bitmap applied to show all the painted markings/lines, or 2) use few terrains, butted-against eachother, with low-res bitmaps showing the general road/walkway outlines, but with a mesh overlay showing all the painted markings/lines? The point is that the painted markings/lines must show clearly.

Any thoughts are greatly appreciated!

I’d just hate to start on such a project, only to be using the wrong technique.

From my experiance in unity there is no best way to do anything in unity. Its just how you work with it and how comfortable you are in the program. Also 1 terrain is more bendable than 1 in this situation. If not 1 terrain then do #1. Its a little easier to do.
I hope this helped you at all. If anything look into t he wiki.

multiple terrains is better, cause the heightmap for the whole terrain is in ram and processed in realtime for the terrain and the larger you need it to be to give reasonable terrain look, the worse its impact.

Drawback is that painting becomes more painfull with multiple terrains as you can only work on one at a time…

For Roads: Use the road addon thats freely available on the asset store by SixTimesNothing

The advantage of multiple terrains is that you can use high-resolution terrain patches just along your driving route, and use low-resolution elsewhere.

The disadvantage is that there is a lot more development work in managing and stitching the multiple terrains.

You will need ludicrously high resolution if you want to paint the line markings on the terrain texture. Either just the lines, or indeed the whole road, really needs to be mesh, not terrain. Then you can have a high resolution texture that repeats every few hundred meters, and so is actually quite small in comparison.

For the terrain itself (with no roads), it may be easier to start with one large terrain. You can always generate patches from that later if you need to (you’ll need to be comfortable with terrain scripting anyway, just to get your stitching right).

Thanks very much for all your answers.

Especially given Warwick’s response, I think I’ll need to use a mesh to display the painted roadway and walkway markings.

Question: I’m skilled at 2-D vector illustration (Illustrator, CorelDraw, etc.). Can anyone recommend which 3-D application would be best for me to convert my 2-D vector graphics of the roadway markings to mesh? I’ve used 3-D software before, but that was 10 years ago… not too current with 3-D these days. Thanks!