Mapping a multi-level builing and area complex with paths on roofs

Hello community,

atm I want to improove bicycle and pedestrian routing at and around our local university. East and west areas are full of bridges and stairs but that seems to be a straight-forward thing. But it is really confusing if you try to find your way through the complex in the center, even as a local.

This is the place in Default OSM View, and F4 Map

The middle building complex is made of multiple levels of pedestrian areas connected by stairs or ways around and on top of a big parking structure. To get an impression, take a look at this picture from wikipedia.

What I did so far: I mapped the levels as separate, partly overlapping pedestrian areas as highway=pedestrian, area=yes with highway-pedestrian-ways inside of the areas for foot&cyclist routing. Ways and areas are tagged with level, starting with 0 at ground level. These ways can be seen on the humanitarian layer. The connecting stairs also have level-tags to address which levels they connect.

There is a bridge connecting another building complex from the north with a combination of these tags:


This combination of tags, exept level, describes the situation there quite good. Basically the elevated pedestrian-areas are big bridges.

Now, questions:
How can I elevate these pedestrian areas?
Adding height to the buildings there seems to be easy, someone already tagged a building in the notheast some time ago. Wiki now has two tags to describe the elevation, height and min_height. Can these also be used on the pedestrian-areas?
Does it make sense to also add the man_made=bridge tag to the pedestrian areas?
How can paths on top of buildings be mapped?
How can I elevate a bridge and tell the map, that one end of the bridge itself is connected to ground and the other one goes to the pedestrian-area?

The middle part of the building complex is, as said, building made for parking so it could be represented as a building. The actual way of describing the place would be a building the middle with a pedestrian-area that is bigger than the building itself on top.

Thanks for help and input!

Interesting challange. Almost like “indoor mapping”
3D renderers mostly use a 2D ground layer. Bridges etc. are not easy to to.
Firstly, routing does not need a visual rendering to route. But how to show the result?
What is the final use/resulst, you need?

In my “OSM go”, the level tags work fine and could be improved if needed:


The green line is a marked way
(The best way to see it, is to use a Google Cardboard)


I’m not up for specific results and according to the phrase “don’t map for renderer” I try to put information in OSM in the way it is intended to be mapped. The place itself is just can be confusing with all those stairs, levels and bridges. It makes sense to map it with additional information about height and since the basic geometry and shapes of the areas are there, it shouldnt be too much of extra work to put it there. When using the map on site it can be important to know if a way is inside, under or on top of a building.

This actually shows the situation there pretty good, that is one way of walking straight over the top level to the stairs at the end.

That is an awesome view of the current situation, but also shows a lot of missing information (especially building heights). How often is this view updated, how much time does it take to display the newest changeset?

The data tiles are read from Overpass. Usually it takes 5-10 minutes to update. In “OSM go” user the key CTRL-M to refresh at the same position

As we just wrote in the “OSM go-Chat”: A smatphone APP für the Campus, using AR-Kit / ARcore would be a dream.
(A simpler help could be an explosion level draving in 2.5D)

P.s: Just fond an error in the OSMgo renderer: Steps were placed twice as high as needed if the end-nodes don’t have a level tag.

Pps.: There another error: Buildings with level=1 and building:levels=1 are rendered as min_level=1 and so don’t have any height at all.
Corrected. Now we have buildings “Flying in the air”, hopefully on an area with the same level:

Layers makes sense for a single buildings, but here it spans on many buildings, and the ground is not flat. so when elevations are rendered, it’ll probably not be aligned like you want.

Unfortunately, F4Map is not rendering bridges & stairs yet, and elevations are still experimental.

for the bridge starting at one level and ending at another, you could map it using many levels ie: levels=0;1 and incline=up/down tag (like for steps)