Rework train same-track collision system and deterministic coupling

- Adds a separate collision system for trains sharing a path
- Moved some coupling-related code to couple.lua and refactor it
- Handle coupling in a way that the initiating train always keeps its ID
- As a side effect, engine has its direction reversed after coupling

1 files changed, 0 insertions, 64 deletions

diff --git a/advtrains/wagons.lua b/advtrains/wagons.lua
index e9b6d7a..4093f06 100644
--- a/advtrains/wagons.lua
+++ b/advtrains/wagons.lua
@@ -1240,70 +1240,6 @@ function wagon:reattach_all()
 	end
 end
 
-local function check_twagon_owner(train, b_first, pname)
-	local wtp = b_first and 1 or #train.trainparts
-	local wid = train.trainparts[wtp]
-	local wdata = advtrains.wagons[wid]
-	if wdata then
-		return advtrains.check_driving_couple_protection(pname, wdata.owner, wdata.whitelist)
-	end
-	return false
-end
-
-function advtrains.safe_couple_trains(id1, id2, t1f, t2f, pname, try_run,v1,v2)
-	
-	if pname and not minetest.check_player_privs(pname, "train_operator") then
-		minetest.chat_send_player(pname, "Missing train_operator privilege")
-		return false
-	end
-	
-	local train1=advtrains.trains[id1]
-	local train2=advtrains.trains[id2]
-	
-	if not advtrains.train_ensure_init(id1, train1)
-		or not advtrains.train_ensure_init(id2, train2) then
-		return false
-	end
-	local wck_t1, wck_t2
-	if pname then
-		wck_t1 = check_twagon_owner(train1, t1f, pname)
-		wck_t2 = check_twagon_owner(train2, t2f, pname)
-	end
-	if (wck_t1 or wck_t2) or not pname then
-		if not v1 then
-			v1 = 0
-		end
-		if not v2 then
-			v2 = 0
-		end
-		if try_run then
-			return true
-		end
-		if t1f then
-			if t2f then
-				v1 = -v1
-				advtrains.invert_train(id1)
-				advtrains.do_connect_trains(id1, id2, v1+v2)
-			else
-				advtrains.do_connect_trains(id2, id1, v1+v2)
-			end
-		else
-			if t2f then
-				advtrains.do_connect_trains(id1, id2, v1+v2)
-			else
-				v2 = -v2
-				advtrains.invert_train(id2)
-				advtrains.do_connect_trains(id1, id2, v1+v2)
-			end
-		end
-		return true
-	else
-		minetest.chat_send_player(pname, "You must be authorized for at least one wagon.")
-		return false
-	end
-end
-
-
 function advtrains.safe_decouple_wagon(w_id, pname, try_run)
 	if not minetest.check_player_privs(pname, "train_operator") then
 		minetest.chat_send_player(pname, "Missing train_operator privilege")