Rail, Fences, other linear structures

Trains and Train Tracks

• most of the 3D construction issues are the same as for roads
• the VTP software doesn't have procedural track construction yet, but it's on the todo list
• Microsoft Train Simulator
  • "Full signaling and traffic system"
  • "Editors included with the game allow you to create your own routes, activities and traffic patterns."
  • "Support for adding locomotives, scenery objects and cabs created with suitable 2D paint packages and 3D modelling packages."
  • does not share any code with their Flight simulator
• 3DTT (3D Transport Tycoon)
  • a game, uses OpenGL, with multitextured landscape and procedural content
  • fully 3D train system, track editing, automatically carves the terrain to the tracks
  • from Peter Dobrovka and WAY-X (a group of German hobby programmers)
  • later made into a commercial game "Schiene und Strasse" ("Rail and Road") although there was a legal fallout with the original authors
• Trainz Railroad Simulator has a lot of virtual terrain functionality and should be evaluated
• other titles listed at UKTrainsim

Linear Structures: Fences and Walls

• in general, there are no computerized records of fence locations in the usual government geodata layers, but they could possibly be implied from property boundaries, when those boundaries are available as GIS data
• vtlib will dynamically construct a fence or a wall, given coordinates (polyline)
• a section of linear structure is described by a set of parameters:
  • post type: wood, steel, none
  • post values: height, spacing, width, depth
  • connect type: wire, chain-link, drystone, privet, stone, railing (3 types), none
  • connect values: top, bottom, width
• in addition, high-level "styles" contain a full set of parameters:
• fence components
  • wooden posts with wire

  • fencepost_64.bmp

    fence lines looks like this:

  • metal posts with chain-link

    chainpost32.bmp

    chain128-4.png

    fence lines looks like this:

• A very common type of fence is "security fence", which consists of chain link with the addition of barbed wire above it in many configurations.  This is found around e.g. every electrical plant and airport in the USA.
  • The fencing industry describes it this way:  "Barbed Wire Extensions: Steel angle extensions, cranked or straight are fixed to the posts and take standard of three lines of barbed wire.  Double Barbed Wire Extensions: Two cranked extensions are provided, each taking three lines of barbed wire."
  • This presents a challenge to parameterization, as there are multiple instances of connection.

Pipelines

• highly suitable for procedural geometry construction
• are there data standards for pipeline attributes?
• PODS - Pipeline Open Data Standard
• ESRI has defined a Pipeline Data Model as a recommendation to allow sharing of data