Re: [Rails-devel] Vertex visit sets (was: 1837 Revenue Calculation)

[Erik V. <eri...@xs...>]

Stefan,

Thanks for your explanation. 
"Vertex set" sounds like a set of vertexes, but I understand you are using
it in a more restricted sense: a "set of mutually exclusive vertexes",
right?
I thought such a thing was called a mutex, not so?

> For the other issue: Sorry I did not realize that the HandmadeTiles was a
> deadend.  So your proposal is to use another id that defines the internal
> structure of Berlin and the two 18EU (B/V Paris) tiles?

No, that wouldn't help in this case.  My preference still is to use
'loop="no"' for these cases (in Map.xml).
The effect should be (if I understand your terminology) that all stations on
a single Tile or MapHex having this access parameter should be included in a
vertex set.

Indeed we need a different mechanism for multi-hex constraints, and perhaps
we should then use that mechanism for single-hex constraints as well, to
replace 'loop="no"'.
The continued use of 'city' (or 'name' or 'mutexID') is also acceptable to
me if we move it to TileSet.xml, which should be easy to do.
For other (better?) solutions I await your detailed proposal.

The use of different internal and external tile IDs is mainly meant to
handle cases where the image does not reflect the actual tile structure
(tracks and stations). In a few cases it is also used to avoid XML code
duplication where structurally identical tiles have different images
(sometimes just a different background colour).
Notorious examples are:
- Goderich (explained in my previous post)
- the 'stick' versions of the brown plain track tiles 544-546 in 18EU and
other games.
- the Altoona and Reading tiles in the 1830 Coalfields and Reading variants.
The tile images show an unconnected station, which in reality should be
handled as if it is connected to all track edges.
In all such cases you'll see either <Tile id="xxx" pic="yyy"> or <Hex ...
tile="xxx" pic="yyy">.

Erik.