Make signal influence point (~halt point) specifiable

Also extend signal api necessarily

1 files changed, 191 insertions, 6 deletions

diff --git a/advtrains_interlocking/signal_api.lua b/advtrains_interlocking/signal_api.lua
index cd1ab54..90fe1fc 100644
--- a/advtrains_interlocking/signal_api.lua
+++ b/advtrains_interlocking/signal_api.lua
@@ -1,7 +1,8 @@
 -- Signal API implementation
 
 
---[[ Signal aspect table:
+--[[
+Signal aspect table:
 asp = {
 	main = {
 		free = <boolean>,
@@ -9,6 +10,14 @@ asp = {
 	},
 	shunt = {
 		free = <boolean>,
+		-- Whether train may proceed as shunt move, on sight
+		-- main aspect takes precedence over this
+		proceed_as_main = <boolean>,
+		-- If an approaching train is a shunt move and "main.free" is set,
+		-- the train may proceed as a train move under the "main" aspect
+		-- If this is not set, shunt moves are NOT allowed to switch to
+		-- a train move, and must stop even if "main.free" is set.
+		-- This is intended to be used for "Halt for shunt moves" signs.
 	}
 	dst = {
 		free = <boolean>,
@@ -17,21 +26,69 @@ asp = {
 	info = {
 		call_on = <boolean>, -- Call-on route, expect train in track ahead
 		dead_end = <boolean>, -- Route ends on a dead end (e.g. bumper)
+		w_speed = <integer>,
+		-- "Warning speed restriction". Supposed for short-term speed
+		-- restrictions which always override any other restrictions
+		-- imposed by "speed" fields, until lifted by a value of -1
 	}
 }
-Signals API:
+-- For "speed" and "w_speed" fields, a value of -1 means that the
+-- restriction is lifted. If they are omitted, the value imposed at
+-- the last aspect received remains valid.
+-- The "dst" subtable can be completely omitted when no explicit dst
+-- aspect should be signalled to the train. In this case, the last
+-- signalled dst aspect remains valid.
+
+== How signals actually work in here ==
+Each signal (in the advtrains universe) is some node that has at least the
+following things:
+- An "influence point" that is set somewhere on a rail
+- An aspect which trains that pass the "influence point" have to obey
+
+There can be static and dynamic signals. Static signals are, roughly
+spoken, signs, while dynamic signals are "real" signals which can display
+different things.
+
+The node definition of a signal node should contain those fields:
 groups = {
-	advtrains_signal = 2,
+  	advtrains_signal = 2,
 	save_in_at_nodedb = 1,
 }
 advtrains = {
 	function set_aspect(pos, node, asp)
-		...
+		-- This function gets called whenever the signal should display
+		-- a new or changed signal aspect. It is not required that
+		-- the signal actually displays the exact same aspect, since
+		-- some signals can not do this by design.
+		-- Example: pure shunt signals can not display a "main" aspect
+		-- and have no effect on train moves, so they will only ever
+		-- honor the shunt.free field for their aspect.
+		
+		-- The aspect passed in here can always be queried using the
+		-- advtrains.interlocking.signal_get_supposed_aspect(pos) function.
+		
+		-- For static signals, this function should be completely omitted
+		-- If this function is ommitted, it won't be possible to use
+		-- route setting on this signal.
+	end
+	function get_aspect(pos, node)
+		-- This function gets called by the train safety system. It
+		should return the aspect that this signal actually displays,
+		not preferably the input of set_aspect.
+		-- For regular, full-featured light signals, they will probably
+		honor all entries in the original aspect, however, e.g.
+		simple shunt signals always return main.free=true regardless of
+		the set_aspect input because they can not signal "Halt" to
+		train moves.
+		-- advtrains.interlocking.DANGER contains a default "all-danger" aspect.
 	end
 }
 on_rightclick = advtrains.interlocking.signal_rc_handler
 can_dig =  advtrains.interlocking.signal_can_dig
+after_dig_node = advtrains.interlocking.signal_after_dig
 
+(If you need to specify custom can_dig or after_dig_node callbacks,
+please call those functions anyway!)
 ]]--
 
 local DANGER = {
@@ -48,6 +105,7 @@ local DANGER = {
 	},
 	info = {}
 }
+advtrains.interlocking.DANGER = DANGER
 
 function advtrains.interlocking.update_signal_aspect(tcbs)
 	if tcbs.signal then
@@ -60,6 +118,11 @@ function advtrains.interlocking.signal_can_dig(pos)
 	return not advtrains.interlocking.db.get_sigd_for_signal(pos)
 end
 
+function advtrains.interlocking.signal_after_dig(pos)
+	-- clear influence point
+	advtrains.interlocking.db.clear_ip_by_signalpos(pos)
+end
+
 function advtrains.interlocking.signal_set_aspect(pos, asp)
 	local node=advtrains.ndb.get_node(pos)
 	local ndef=minetest.registered_nodes[node.name]
@@ -75,7 +138,7 @@ function advtrains.interlocking.signal_rc_handler(pos, node, player, itemstack,
 		advtrains.interlocking.show_signalling_form(sigd, pname)
 	else
 		-- permit to set aspect manually
-		minetest.show_formspec(pname, "at_il_sigasp_"..minetest.pos_to_string(pos), "field[aspect;Set Aspect (F/D)Speed(F/D)Speed(F/D);D0D0D]")
+		minetest.show_formspec(pname, "at_il_sigasp_"..minetest.pos_to_string(pos), "field[aspect;Set Aspect (F/D)Speed(F/D)Speed(F/D) ['A' to assign IP];D0D0D]")
 	end
 end
 
@@ -85,6 +148,10 @@ minetest.register_on_player_receive_fields(function(player, formname, fields)
 	local pos
 	if pts then pos = minetest.string_to_pos(pts) end
 	if pos and fields.aspect then
+		if fields.aspect == "A" then
+			advtrains.interlocking.show_ip_form(pos, pname)
+			return
+		end
 		local mfs, msps, dfs, dsps, shs = string.match(fields.aspect, "^([FD])([0-9]+)([FD])([0-9]+)([FD])$")
 		local asp = {
 			main = {
@@ -108,7 +175,7 @@ minetest.register_on_player_receive_fields(function(player, formname, fields)
 end)
 
 -- Returns the aspect the signal at pos is supposed to show
-function advtrains.interlocking.signal_get_aspect(pos)
+function advtrains.interlocking.signal_get_supposed_aspect(pos)
 	local sigd = advtrains.interlocking.db.get_sigd_for_signal(pos)
 	if sigd then
 		local tcbs = advtrains.interlocking.db.get_tcbs(sigd)
@@ -118,3 +185,121 @@ function advtrains.interlocking.signal_get_aspect(pos)
 	end
 	return DANGER;
 end
+
+-- Returns the actual aspect of the signal at position, as returned by the nodedef.
+-- returns nil
+function advtrains.interlocking.signal_get_aspect(pos)
+	local node=advtrains.ndb.get_node(pos)
+	local ndef=minetest.registered_nodes[node.name]
+	if ndef and ndef.advtrains and ndef.advtrains.get_aspect then
+		return ndef.advtrains.get_aspect(pos, node)
+	end
+end
+
+local players_assign_ip = {}
+
+-- shows small info form for signal IP state/assignment
+-- only_notset: show only if it is not set yet (used by signal tcb assignment)
+function advtrains.interlocking.show_ip_form(pos, pname, only_notset)
+	local form = "size[7,5]label[0.5,0.5;Signal at "..minetest.pos_to_string(pos).."]"
+	local pts, connid = advtrains.interlocking.db.get_ip_by_signalpos(pos)
+	if pts then
+		form = form.."label[0.5,1.5;Influence point is set at "..pts.."/"..connid.."]"
+		form = form.."button_exit[0.5,2.5;  5,1;show;Show]"
+		form = form.."button_exit[0.5,3.5;  5,1;clear;Clear]"
+	else
+		form = form.."label[0.5,1.5;Influence point is not set.]"
+		form = form.."label[0.5,2.0;It is recommended to set an influence point.]"
+		form = form.."label[0.5,2.5;This is the point where trains will obey the signal.]"
+		
+		form = form.."button_exit[0.5,3.5;  5,1;set;Set]"
+	end
+	if not only_notset or not pts then
+		minetest.show_formspec(pname, "at_il_ipassign_"..minetest.pos_to_string(pos), form)
+	end
+end
+
+local function ipmarker(ipos, connid)
+	local node_ok, conns, rhe = advtrains.get_rail_info_at(ipos, advtrains.all_tracktypes)
+	if not node_ok then return end
+	local yaw = advtrains.dir_to_angle(conns[connid].c)
+	
+	-- using tcbmarker here
+	local obj = minetest.add_entity(vector.add(ipos, {x=0, y=0.2, z=0}), "advtrains_interlocking:tcbmarker")
+	if not obj then return end
+	obj:set_yaw(yaw)
+	obj:set_properties({
+		textures = { "at_il_signal_ip.png" },
+	})
+end
+
+minetest.register_on_player_receive_fields(function(player, formname, fields)
+	local pname = player:get_player_name()
+	if not minetest.check_player_privs(pname, {train_operator=true, interlocking=true}) then
+		return
+	end
+	local pts = string.match(formname, "^at_il_ipassign_([^_]+)$")
+	local pos
+	if pts then
+		pos = minetest.string_to_pos(pts)
+	end
+	if pos then
+		if fields.set then
+			advtrains.interlocking.signal_init_ip_assign(pos, pname)
+		elseif fields.clear then
+			advtrains.interlocking.db.clear_ip_by_signalpos(pos)
+		elseif fields.show then
+			local ipts, connid = advtrains.interlocking.db.get_ip_by_signalpos(pos)
+			if not ipts then return end
+			local ipos = minetest.string_to_pos(ipts)
+			ipmarker(ipos, connid)
+		end
+	end
+end)
+
+-- inits the signal IP assignment process
+function advtrains.interlocking.signal_init_ip_assign(pos, pname)
+	if not minetest.check_player_privs(pname, "interlocking") then
+		minetest.chat_send_player(pname, "Insufficient privileges to use this!")
+		return
+	end
+	--remove old IP
+	advtrains.interlocking.db.clear_ip_by_signalpos(pos)
+	minetest.chat_send_player(pname, "Configuring Signal: Please look in train's driving direction and punch rail to set influence point.")
+	
+	players_assign_ip[pname] = pos
+end
+
+minetest.register_on_punchnode(function(pos, node, player, pointed_thing)
+	local pname = player:get_player_name()
+	if not minetest.check_player_privs(pname, "interlocking") then
+		return
+	end
+	-- IP assignment
+	local signalpos = players_assign_ip[pname]
+	if signalpos then
+		if vector.distance(pos, signalpos)<=50 then
+			local node_ok, conns, rhe = advtrains.get_rail_info_at(pos, advtrains.all_tracktypes)
+			if node_ok and #conns == 2 then
+				
+				local yaw = player:get_look_horizontal()
+				local plconnid = advtrains.yawToClosestConn(yaw, conns)
+				
+				-- add assignment if not already present.
+				local pts = advtrains.roundfloorpts(pos)
+				if not advtrains.interlocking.db.get_ip_signal_asp(pts, plconnid) then
+					advtrains.interlocking.db.set_ip_signal(pts, plconnid, signalpos)
+					ipmarker(pos, plconnid)
+					minetest.chat_send_player(pname, "Configuring Signal: Successfully set influence point")
+				else
+					minetest.chat_send_player(pname, "Configuring Signal: Influence point of another signal is already present!")
+				end
+			else
+				minetest.chat_send_player(pname, "Configuring Signal: This is not a normal two-connection rail! Aborted.")
+			end
+		else
+			minetest.chat_send_player(pname, "Configuring Signal: Node is too far away. Aborted.")
+		end
+		players_assign_ip[pname] = nil
+	end
+end)