Fix visible cable connection for irregular items

The switching station and supply converter only semantically connect to
cables in particular directions.  Make them visually connect only in
the matching directions.  This is done by special-casing in the cable
update logic.  If more irregular items arise in the future, or the
existing items start to need facedir logic, this should be generalised
into something like the connect_sides system for pneumatic tubes.

diff --git a/manual.md b/manual.md
index fb21f457abd3ed2afaa3fc2127a76251907e5ebe..c3570d8b3481ec967fe9be11f4a087542ff1ffd0 100644 (file)
--- a/manual.md
+++ b/manual.md
@@ -690,9 +690,7 @@ no energy will flow without one.  Unlike most electrical items, the
 switching station is not voltage-specific: the same item will manage
 a network of any tier.  However, also unlike most electrical items,
 it is picky about the direction in which it is connected to the cable:
-the cable must be directly below the switching station.  Due to a bug,
-the switching station will visually appear to connect to cables on other
-sides, but those connections don't do anything.
+the cable must be directly below the switching station.
 
 Hovering over a network's switching station will show the aggregate energy
 supply and demand, which is useful for troubleshooting.  Electrical energy

diff --git a/technic/machines/register/cables.lua b/technic/machines/register/cables.lua
index 9ec1cfa17a6b1850ffaa8b1d49e5d17884265239..7abdfcb79ec707073dd1a26edab7db62e3f83ea0 100644 (file)
--- a/technic/machines/register/cables.lua
+++ b/technic/machines/register/cables.lua
@@ -130,7 +130,11 @@ end
 function technic.cables_should_connect(pos1, pos2, tier)
        local name = minetest.get_node(pos2).name
 
-       if technic.is_tier_cable(name, tier) then
+       if name == "technic:switching_station" then
+               return pos2.y == pos1.y + 1 and "machine" or false
+       elseif name == "technic:supply_converter" then
+               return math.abs(pos2.y - pos1.y) == 1 and "machine" or false
+       elseif technic.is_tier_cable(name, tier) then
                return "cable"
        elseif technic.machines[tier][name] then
                return "machine"