Runway, Taxiways, Apron finished. Starting on Decals. Then Textures.
Like to thank, Rodeo and Thomasph for their lessons and inspiration to get going again after stopping in frustration last year.
I use a different technique to Rodeo as my taxi ways are not usually straight but curved (I don't know what it is with Australian airports).
1. So I Boolean subtract my Runways out of my outside mesh. This allows you to build cross runways really easily.(Remember: to duplicate the runway you are going to use to cut through the other as one of them will disappear)
2. Then select your outside mesh, go to sideview and cut the top vertices, and delete the rest and then 0 all heights so they are flat. do the same for the runways.
3. I then click and trace around all the taxi ways using the polygon, using multiple clicks around corners and curves and less on straights. Take note here, you are not actually tracing the taxi ways but rather the negative spaces, so the grass areas you want taken out.
So you can do them all at once and merge, or one at a time.
Important bit. now with the poly layer selected in the hierarchy,
a: select surface, change to side view, and extrude using your ctrl
b: select group, fill holes, and move it back down so it cuts through your Outside mesh
c: flip Normals, what you are looking for is your normals coming out of the side when you look down from a top view
d: boolean knife and cutaway.
e: Select Outside first then the poly and merge
4. Now you can highlight the taxi way using the Surface Tool, cut, paste, rename, done.
I hope this helps those out there wanting to build their own airports. It's really easy. I might make a video.