Interlocking: Create demo signals, signal API and model for TCB configurer node

1 files changed, 14 insertions, 4 deletions

diff --git a/advtrains_interlocking/database.lua b/advtrains_interlocking/database.lua
index 7a49383..61bf5ad 100644
--- a/advtrains_interlocking/database.lua
+++ b/advtrains_interlocking/database.lua
@@ -5,8 +5,7 @@ The interlocking system is based on track circuits.
 Track circuit breaks must be manually set by the user. Signals must be assigned to track circuit breaks and to a direction(connid).
 To simplify the whole system, there is no overlap.
 == Trains ==
-A train always reserves the space between two signals facing it. All track circuits in this space
-have a reservation entry TRAIN with the train's ID
+Trains always occupy certain track circuits. These are shown red in the signalbox view (TRAIN occupation entry).
 == Database storage ==
 The things that are actually saved are the Track Circuit Breaks. Each TCB holds a list of the TCBs that are adjacent in each direction.
 TC occupation/state is then saved inside each (TCB,Direction) and held in sync across all TCBs adjacent to this one. If something should not be in sync,
@@ -21,6 +20,8 @@ A track circuit does not have a state as such, but has more or less a list of "r
 type can be one of these:
 TRAIN See Trains obove
 ROUTE Route set from a signal, but no train has yet passed that signal.
+Not implemented (see note by reversible): OWNED - former ROUTE segments that a train has begun passing (train_id assigned)
+		  - Space behind a train up to the next signal, when a TC is set as REVERSIBLE
 Certain TCs can be marked as "allow call-on".
 == Route setting: ==
 Routes are set from a signal (the entry signal) to another signal facing the same direction (the exit signal)
@@ -35,8 +36,17 @@ Apart from this, we need to set turnouts
 It will be necessary to join and split trains using call-on routes. A call-on route may be set when:
 - there are no ROUTE reservations
 - there are TRAIN reservations only inside TCs that have "allow call-on" set
-
-
+== TC Properties ==
+Note: Reversible property will not be implemented, assuming everything as non-rev.
+This is sufficient to cover all use cases, and is done this way in reality.
+	REVERSIBLE - Whether trains are allowed to reverse while on track circuit
+	This property is supposed to be set for station tracks, where there is a signal at each end, and for sidings.
+	It should in no case be set for TCs covering turnouts, or for main running lines.
+	When a TC is not set as reversible, the OWNED status is cleared from the TC right after the train left it,
+	to allow other trains to pass it.
+	If it is set reversible, interlocking will keep the OWNED state behind the train up to the next signal, clearing it
+	as soon as the train passes another signal or enters a non-reversible section.
+CALL_ON_ALLOWED - Whether this TC being blocked (TRAIN or ROUTE) does not prevent shunt routes being set through this TC
 == More notes ==
 - It may not be possible to switch turnouts when their TC has any state entry