created git repository

1 files changed, 215 insertions, 0 deletions

diff --git a/helpers.lua b/helpers.lua
new file mode 100644
index 0000000..02367d8
--- /dev/null
+++ b/helpers.lua
@@ -0,0 +1,215 @@
+--advtrains by orwell96, see readme.txt

+local print=function(t) minetest.log("action", t) minetest.chat_send_all(t) end

+

+function advtrains.dirCoordSet(coord, dir)

+	local x=0

+	local z=0

+	--local dir=(dirx+2)%8

+	if(dir==6) then

+		x=-1

+	elseif (dir==7) then

+		x=-1

+		z=1

+	elseif (dir==0) then

+		z=1

+	elseif (dir==1) then

+		z=1

+		x=1

+	elseif (dir==2) then

+		x=1

+	elseif (dir==3) then

+		x=1

+		z=-1

+	elseif (dir==4) then

+		z=-1

+	elseif (dir==5) then

+		z=-1

+		x=-1

+	else

+		error("advtrains: in helpers.lua/dirCoordSet() given dir="..(dir or "nil"))

+	end

+

+

+	return {x=coord.x+x, y=coord.y, z=coord.z+z}

+end

+function advtrains.dirToCoord(dir)

+	return advtrains.dirCoordSet({x=0, y=0, z=0}, dir)

+end

+

+function advtrains.maxN(list, expectstart)

+	local n=expectstart or 0

+	while list[n] do

+		n=n+1

+	end

+	return n-1

+end

+

+function advtrains.minN(list, expectstart)

+	local n=expectstart or 0

+	while list[n] do

+		n=n-1

+	end

+	return n+1

+end

+

+--vertical_transmit:

+--[[

+rely1, rely2 tell to which height the connections are pointed to. 1 means it will go up the next node

+

+]]

+

+function advtrains.conway(midreal, prev, drives_on)--in order prev,mid,return

+	local mid=advtrains.round_vector_floor_y(midreal)

+	if(not advtrains.is_track_and_drives_on(minetest.get_node(mid).name, drives_on)) then

+		--print("[advtrains]in conway: no rail, returning!")

+		return nil

+	end

+	if(not prev or not advtrains.is_track_and_drives_on(minetest.get_node(advtrains.round_vector_floor_y(prev)).name, drives_on)) then

+		--print("[advtrains]in conway: no prev rail, there should be an initial path!, returning!")

+		return nil

+	end

+	local midnode=minetest.get_node_or_nil(mid)

+	if not midnode then --print("[advtrains][conway] midnode is ignore")

+		return nil 

+	end

+	

+	local middir1, middir2, midrely1, midrely2=advtrains.get_track_connections(midnode.name, midnode.param2)

+	

+	local next, chkdir, chkrely, y_offset

+	y_offset=0

+	--print("[advtrains] in order mid1,mid2",middir1,middir2)

+	--try if it is dir1

+	local cor1=advtrains.dirCoordSet(mid, middir2)--<<<<

+	if math.floor(cor1.x+0.5)==math.floor(prev.x+0.5) and math.floor(cor1.z+0.5)==math.floor(prev.z+0.5) then--this was previous

+		next=advtrains.dirCoordSet(mid, middir1)

+		if midrely1>=1 then

+			next.y=next.y+1

+			--print("[advtrains]found midrely1 to be >=1: next is now "..(next and minetest.pos_to_string(next) or "nil"))

+			y_offset=1

+		end

+		chkdir=middir1

+		chkrely=midrely1

+		--print("[advtrains]dir2 applied next pos:",minetest.pos_to_string(next),"(chkdir is ",chkdir,")")

+	end

+	--dir2???

+	local cor2=advtrains.dirCoordSet(mid, middir1)--<<<<

+	if math.floor(cor2.x+0.5)==math.floor(prev.x+0.5) and math.floor(cor2.z+0.5)==math.floor(prev.z+0.5) then

+		next=advtrains.dirCoordSet(mid, middir2)--dir2 wird überprüft, alles gut.

+		if midrely2>=1 then

+			next.y=next.y+1

+			--print("[advtrains]found midrely2 to be >=1: next is now "..(next and minetest.pos_to_string(next) or "nil"))

+			y_offset=1

+		end

+		chkdir=middir2

+		chkrely=midrely2

+		--print("[advtrains] dir2 applied next pos:",minetest.pos_to_string(next),"(chkdir is ",chkdir,")")

+	end

+	--print("[advtrains]dir applied next pos: "..(next and minetest.pos_to_string(next) or "nil").."(chkdir is "..(chkdir or "nil")..", y-offset "..y_offset..")")

+	--is there a next

+	if not next then

+		print("[advtrains]in conway: no next rail(nil), returning!")

+		return nil

+	end

+	local nextnode=minetest.get_node_or_nil(advtrains.round_vector_floor_y(next))

+	if not nextnode then print("[advtrains][conway] nextnode is ignore") 

+		return nil 

+	end

+	

+	--is it a rail?

+	if(not advtrains.is_track_and_drives_on(nextnode.name, drives_on)) then

+		print("[advtrains]in conway: next "..minetest.pos_to_string(next).." not a rail, trying one node below!")

+		next.y=next.y-1

+		y_offset=y_offset-1

+		

+		nextnode=minetest.get_node_or_nil(advtrains.round_vector_floor_y(next))

+		if not nextnode then --print("[advtrains][conway] nextnode is ignore") 

+			return nil

+		end

+		if(not advtrains.is_track_and_drives_on(nextnode.name, drives_on)) then

+			print("[advtrains]in conway: one below "..minetest.pos_to_string(next).." is not a rail either, returning!")

+			return nil

+		end

+	end

+	--print("[advtrains]trying to find if rail connects: "..(next and minetest.pos_to_string(next) or "nil").."(chkdir is "..(chkdir or "nil")..", y-offset "..y_offset..")")

+	

+	local nextdir1, nextdir2, nextrely1, nextrely2, nextrailheight=advtrains.get_track_connections(nextnode.name, nextnode.param2)

+	

+	--is this next rail connecting to the mid?

+	if not ( (((nextdir1+4)%8)==chkdir and nextrely1==chkrely-y_offset) or (((nextdir2+4)%8)==chkdir and nextrely2==chkrely-y_offset) ) then

+		print("[advtrains]in conway: next "..minetest.pos_to_string(next).." not connecting, trying one node below!")

+		next.y=next.y-1

+		y_offset=y_offset-1

+		

+		nextdir1, nextdir2, nextrely1, nextrely2, nextrailheight=advtrains.get_track_connections(nextnode.name, nextnode.param2)

+		if not ( (((nextdir1+4)%8)==chkdir and nextrely1==chkrely) or (((nextdir2+4)%8)==chkdir and nextrely2==chkrely) ) then

+			print("[advtrains]in conway: next "..minetest.pos_to_string(next).." rail not connecting, returning!")

+			--print("[advtrains] in order mid1,2,next1,2,chkdir "..middir1.." "..middir2.." "..nextdir1.." "..nextdir2.." "..chkdir)

+			return nil

+		end

+	end

+	

+	--print("[advtrains]conway found rail.")

+	return vector.add(advtrains.round_vector_floor_y(next), {x=0, y=nextrailheight, z=0}), chkdir

+end

+

+function advtrains.round_vector_floor_y(vec)

+	return {x=math.floor(vec.x+0.5), y=math.floor(vec.y), z=math.floor(vec.z+0.5)}

+end

+

+function advtrains.yawToDirection(yaw, conn1, conn2)

+	if not conn1 or not conn2 then

+		error("given nil to yawToDirection: conn1="..(conn1 or "nil").." conn2="..(conn1 or "nil"))

+	end

+	local yaw1=math.pi*(conn1/4)

+	local yaw2=math.pi*(conn2/4)

+	if advtrains.minAngleDiffRad(yaw, yaw1)<advtrains.minAngleDiffRad(yaw, yaw2) then--change to > if weird behavior

+		return conn2

+	else

+		return conn1

+	end

+end

+

+function advtrains.minAngleDiffRad(r1, r2)

+	local try1=r2-r1

+	local try2=(r2+2*math.pi)-r1

+	local try3=r2-(r1+2*math.pi)

+	if math.min(math.abs(try1), math.abs(try2), math.abs(try3))==math.abs(try1) then

+		return try1

+	end

+	if math.min(math.abs(try1), math.abs(try2), math.abs(try3))==math.abs(try2) then

+		return try2

+	end

+	if math.min(math.abs(try1), math.abs(try2), math.abs(try3))==math.abs(try3) then

+		return try3

+	end

+end

+function advtrains.dumppath(path)

+	if not path then print("dumppath: no path(nil)") return end

+	local min=advtrains.minN(path)

+	local max=advtrains.maxN(path)

+	for i=min, max do print("["..i.."] "..(path[i] and minetest.pos_to_string(path[i]) or "nil")) end

+end

+

+function advtrains.merge_tables(a, ...)

+	local new={}

+	for _,t in ipairs({a,...}) do

+		for k,v in pairs(t) do new[k]=v end

+	end

+	return new

+end

+function advtrains.yaw_from_3_positions(prev, curr, next)

+	local pts=minetest.pos_to_string

+	--print("p3 "..pts(prev)..pts(curr)..pts(next))

+	local prev2curr=math.atan2((curr.x-prev.x), (prev.z-curr.z))

+	local curr2next=math.atan2((next.x-curr.x), (curr.z-next.z))

+	--print("y3 "..(prev2curr*360/(2*math.pi)).." "..(curr2next*360/(2*math.pi)))

+	return prev2curr+(advtrains.minAngleDiffRad(prev2curr, curr2next)/2)

+end

+function advtrains.get_wagon_yaw(front, first, second, back, pct)

+	local pts=minetest.pos_to_string

+	--print("p "..pts(front)..pts(first)..pts(second)..pts(back))

+	local y2=advtrains.yaw_from_3_positions(second, first, front)

+	local y1=advtrains.yaw_from_3_positions(back, second, first)

+	--print("y "..(y1*360/(2*math.pi)).." "..(y2*360/(2*math.pi)))

+	return y1+advtrains.minAngleDiffRad(y1, y2)*pct

+end