# Bridge3D

Bridge3D
Status: Proposed (under way)
Proposed by: Marek_kleciak
Applies to:
Definition: Bridge in 3D
Drafted on: 2014-07-22

This wiki page describes some ideas for 3D modeling of bridges. This is recently only working version for one proposal. Ideas, suggestions are welcome.

## Status Quo

### 2D

Rendering has known problems with bridges with several separated lanes necessarily for right routing:

Use of area concept for bridges helps to render better 2D maps, see man_made=bridge

### 3D

For simple multilevel bridges this proposal can be used to map bridge levels.

Another idea would be use of building=yes concept for drawing of building parts.

#### Idea

Modify S3DB concept and draw bridges as well.

Example:

Simple bridge with pillar.

Section

##### Tagging: open questions and ideas
• column=yes or pillar=yes or barrier=wall with area=yes (please vote)
• bridge:part=yes or building:part=yes (please vote)
• how to tag value H1? (Thickness of main bridge plateau): bridge:height:ele=90
• bridge:height:ground_level=25
• bridge:min_level=23.5

#### Bridges with height profile

Very often is the surface of a bridge not flat. In such situations the surface of the bridge shuuld be divided in more areas tagged as: bridge:part=ramp The street vector (highway=* + bridge=yes) gets two (different) ele=* values respectively on both sides of bridge:part.

Sketch: dividing of bridge area in subareas bridge:part=yes

Top and side view of typical bridge with different heights.

#### How to map height

ele=* values on highway=* on the outline shape of bridge:part=ramp