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(svn r4281) -Cleanup: Begun cleaning up elrail code a bit, mostly comments and enum/array alignment

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celestar
2006-04-05 08:28:03 +00:00
parent 8362990f8c
commit 4acb8d5364
2 changed files with 223 additions and 134 deletions
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elrail.c
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@@ -1,6 +1,6 @@
/* $Id$ */
/** @file elrail.c
* This file deals with displaying wires and pylons for electric railway systems.
This file deals with displaying wires and pylons for electric railways.
<h2>Basics</h2>
<h3>Tile Types</h3>
@@ -22,21 +22,23 @@ Group 3: Tiles with both an odd X and Y coordnate.
<h4>Control Points</h4>
A Pylon Control Point (PCP) is a position where a wire (or rather two)
is mounted onto a pylon.
Each NRT does contain 4 PCPs which are mapped to a byte
variable and are represented by the DiagDirection enum:
Each NRT does contain 4 PCPs which are bitmapped to a byte
variable and are represented by the DiagDirection enum
A wire that ends on the PCP has a dark ending, otherwise the end is bright.<p>
Each track ends on two PCPs and thus requires one pylon on each end. However,
there is one exception: Straight-and-level tracks only have one pylon every
other tile.
Now on each edge there are two PCPs: One from each adjacent tile. Both PCPs are merged
using an OR matrix (i. e. if one tile needs a PCP at the postion in question, both
tiles get it).
Now on each edge there are two PCPs: One from each adjacent tile. Both PCPs
are merged using an OR operation (i. e. if one tile needs a PCP at the postion
in question, both tiles get it).
<h4>Position Points</h4>
A Pylon Position Point (PPP) is a position where a pylon is located on the ground.
Each PCP owns 8 in (45 degree steps) PPPs that are located around it. PPPs are numbered
0 to 7 with 0 starting north and numbering in clockwise direction. Each track bit has PPPs
that are impossible (because the pylon would be situated on the track), preferred (because
the pylon would be rectangular to the track). PPPs are represented by the Direction enum.
A Pylon Position Point (PPP) is a position where a pylon is located on the
ground. Each PCP owns 8 in (45 degree steps) PPPs that are located around
it. PPPs are represented using the Direction enum. Each track bit has PPPs
that are impossible (because the pylon would be situated on the track) and
some that are preferred (because the pylon would be rectangular to the track).
<img src="../../elrail_tile.png">
<img src="../../elrail_track.png">