Building ZONE arrows and plop arrows..

[SC4BOY 21]

I have a question I've never seen addressed.. I am a bit confused by plop buildings and zone "arrows"

 It seems that RESIDENTIAL only has to have arrows that MUST be adjacent to roads.. Other lots INDUSTRY and COMMERCE seem to work as long as the area of the "ZONE" is in reasonable proximity to transport and is not nearly as picky.

For plop items like railroad stations, bus stops, and most other "non RCI" buildings it SEEMS that the arrows only determine the "level set" of the plop.. for example if a busstop is to be placed on a sloped section of road, you can point the arrow "toward highest ground" and the lot will level at the high point. If you point the arrow "in the middle" ie pointing at the road, it will level sort of between the high and low. If you point it "downhill" it will level with the lowest or near so level of terrain.. These seem to have no relationship to whether the busstop will be used or not, just to the level at which it is built.. In all cases it is actively used by sims as a busstop.. other buildings seem to work the same.. BUT occasionally there is a lot that if not pointed toward the road (or whatever transport method is needed) such as a fire station or police station, it will fuss at you because the "firemen cannot get out of their station".. 

Is there any easy way to predict when the arrow means which thing??

If this explaination is not clear I can post some pics but it should be pretty clear. 

EDIT: This seemed to be the right spot to post this.. if it is wrong feel free to move it.. thx

[Constantina 5]

Generally, the arrows mean the entrance point of the lot. The lots will eventually grow by itself if it has the space to do so.

[sumwonyuno 42]

for residential and commerical, the arrow has to be pointing to a surface roadway [street, road, one-way, avenue] for the zone to develop. however sims can leave their house/building and enter a commercial job from the back or side, if there is a roadway touching that side. industry, i zone no more than 4 tiles away from a roadway. sims can even enter/exit from a neighboring industry job to get to the building.

as 4 civic buildings [especially the police and firefighters... mayb the elem. n high schools if u play UDI missions], u should make the arrow touching a roadway. landmarks and parks dont' matter for the arrow.

also, u can press the shift, ctrl, alt, or combination of them at the same time as u zone to make custom size zone lots. im not sure which key will change the direction of the arrow if u put the zone next to an intersection [two choices of roadway for the arrow]

[edit] mass transit... bus stops can b any direction as long as [again] it touches a roadway.  same goes for the other mass transit options [subways, rail, monorail, etc]... they need that + their dedicated transit lines.

however for the ferrys [if anyone uses them] u have to directly connect them to the roadway network [drag a road into the ferry station at the textured road area]... and of course have to be partially in water.  im not sure about the airport n seaports... i just usually put a roadway around the airport and following the side of the arrow for the seaports.

[SC4BOY 21]

Do the arrows of parks and similar things have any benefits added if touching roads, etc or does it not matter if they don't have "connections"?

[A Nonny Moose 8,263]

Don't think so.  I sometimes place parks where there are no roads.