advtrains/trainlogic.lua

543 lines
20 KiB
Lua

--trainlogic.lua
--controls train entities stuff about connecting/disconnecting/colliding trains and other things
local print=function(t) minetest.log("action", t) minetest.chat_send_all(t) end
advtrains.train_accel_force=5--per second and divided by number of wagons
advtrains.train_brake_force=3--per second, not divided by number of wagons
advtrains.train_emerg_force=10--for emergency brakes(when going off track)
advtrains.audit_interval=10
advtrains.all_traintypes={}
function advtrains.register_train_type(name, drives_on, max_speed)
advtrains.all_traintypes[name]={}
advtrains.all_traintypes[name].drives_on=drives_on
advtrains.all_traintypes[name].max_speed=max_speed or 10
end
advtrains.trains={}
--load initially
advtrains.fpath=minetest.get_worldpath().."/advtrains"
local file, err = io.open(advtrains.fpath, "r")
if not file then
local er=err or "Unknown Error"
print("[advtrains]Failed loading advtrains save file "..er)
else
local tbl = minetest.deserialize(file:read("*a"))
if type(tbl) == "table" then
advtrains.trains=tbl
end
file:close()
end
advtrains.save = function()
--print("[advtrains]saving")
advtrains.invalidate_all_paths()
local datastr = minetest.serialize(advtrains.trains)
if not datastr then
minetest.log("error", "[advtrains] Failed to serialize train data!")
return
end
local file, err = io.open(advtrains.fpath, "w")
if err then
return err
end
file:write(datastr)
file:close()
end
minetest.register_on_shutdown(advtrains.save)
advtrains.save_and_audit_timer=advtrains.audit_interval
minetest.register_globalstep(function(dtime)
advtrains.save_and_audit_timer=advtrains.save_and_audit_timer-dtime
if advtrains.save_and_audit_timer<=0 then
--print("[advtrains] audit step")
--clean up orphaned trains
for k,v in pairs(advtrains.trains) do
advtrains.update_trainpart_properties(k)
if #v.trainparts==0 then
advtrains.trains[k]=nil
end
end
--save
advtrains.save()
advtrains.save_and_audit_timer=advtrains.audit_interval
end
--regular train step
for k,v in pairs(advtrains.trains) do
advtrains.train_step(k, v, dtime)
end
end)
function advtrains.train_step(id, train, dtime)
--TODO check for all vars to be present
--if not train.last_pos then advtrains.trains[id]=nil return end
if not advtrains.pathpredict(id, train) then
--print("pathpredict failed(returned false)")
train.velocity=0
train.tarvelocity=0
return
end
local path=advtrains.get_or_create_path(id, train)
if not path then
train.velocity=0
train.tarvelocity=0
--print("train has no path")
return
end
--apply off-track handling:
local front_off_track=train.max_index_on_track and train.index>train.max_index_on_track
local back_off_track=train.min_index_on_track and (train.index-train.trainlen)<train.min_index_on_track
if front_off_track and back_off_track then--allow movement in both directions
if train.tarvelocity>1 then train.tarvelocity=1 end
if train.tarvelocity<-1 then train.tarvelocity=-1 end
elseif front_off_track then--allow movement only backward
if train.tarvelocity>0 then train.tarvelocity=0 end
if train.tarvelocity<-1 then train.tarvelocity=-1 end
elseif back_off_track then--allow movement only forward
if train.tarvelocity>1 then train.tarvelocity=1 end
if train.tarvelocity<0 then train.tarvelocity=0 end
end
--move
if not train.velocity then
train.velocity=0
end
train.index=train.index and train.index+((train.velocity/(train.path_dist[math.floor(train.index)] or 1))*dtime) or 0
--check for collisions by finding objects
--front
local search_radius=4
local posfront=path[math.floor(train.index+1)]
if posfront then
local objrefs=minetest.get_objects_inside_radius(posfront, search_radius)
for _,v in pairs(objrefs) do
local le=v:get_luaentity()
if le and le.is_wagon and le.initialized and le.train_id~=id then
advtrains.try_connect_trains(id, le.train_id)
end
end
end
local posback=path[math.floor(train.index-(train.trainlen or 0)-1)]
if posback then
local objrefs=minetest.get_objects_inside_radius(posback, search_radius)
for _,v in pairs(objrefs) do
local le=v:get_luaentity()
if le and le.is_wagon and le.initialized and le.train_id~=id then
advtrains.try_connect_trains(id, le.train_id)
end
end
end
--handle collided_with_env
if train.recently_collided_with_env then
train.tarvelocity=0
if train.velocity==0 then
train.recently_collided_with_env=false--reset status when stopped
end
end
if train.locomotives_in_train==0 then
train.tarvelocity=0
end
--apply tarvel(but with physics in mind!)
if train.velocity~=train.tarvelocity then
local applydiff=0
local mass=#train.trainparts
local diff=math.abs(train.tarvelocity)-math.abs(train.velocity)
if diff>0 then--accelerating, force will be brought on only by locomotives.
--print("accelerating with default force")
applydiff=(math.min((advtrains.train_accel_force*train.locomotives_in_train*dtime)/mass, math.abs(diff)))
else--decelerating
if front_off_track or back_off_track or train.recently_collided_with_env then --every wagon has a brake, so not divided by mass.
--print("braking with emergency force")
applydiff=(math.min((advtrains.train_emerg_force*dtime), math.abs(diff)))
else
--print("braking with default force")
applydiff=(math.min((advtrains.train_brake_force*dtime), math.abs(diff)))
end
end
train.velocity=train.velocity+(applydiff*math.sign(train.tarvelocity-train.velocity))
end
end
--the 'leader' concept has been overthrown, we won't rely on MT's "buggy object management"
--structure of train table:
--[[
trains={
[train_id]={
trainparts={
[n]=wagon_id
}
path={path}
velocity
tarvelocity
index
trainlen
path_inv_level
last_pos |
last_dir | for pathpredicting.
no_connect_for_movements (index way counter for when not to connect again) TODO implement
}
}
--a wagon itself has the following properties:
wagon={
unique_id
train_id
pos_in_train (is index difference, including train_span stuff)
pos_in_trainparts (is index in trainparts tabel of trains)
}
inherited by metatable:
wagon_proto={
wagon_span
}
]]
--returns new id
function advtrains.create_new_train_at(pos, pos_prev, traintype)
local newtrain_id=os.time()..os.clock()
while advtrains.trains[newtrain_id] do newtrain_id=os.time()..os.clock() end--ensure uniqueness(will be unneccessary)
advtrains.trains[newtrain_id]={}
advtrains.trains[newtrain_id].last_pos=pos
advtrains.trains[newtrain_id].last_pos_prev=pos_prev
advtrains.trains[newtrain_id].traintype=traintype
advtrains.trains[newtrain_id].tarvelocity=0
advtrains.trains[newtrain_id].velocity=0
advtrains.trains[newtrain_id].trainparts={}
return newtrain_id
end
--returns false on failure. handle this case!
function advtrains.pathpredict(id, train)
--print("pos ",x,y,z)
--::rerun::
if not train.index then train.index=0 end
if not train.path or #train.path<2 then
if not train.last_pos then
--no chance to recover
print("[advtrains]train hasn't saved last-pos, removing train.")
advtrains.train[id]=nil
return false
end
local node=minetest.get_node_or_nil(advtrains.round_vector_floor_y(train.last_pos))
if not node then
--print("pathpredict:last_pos node "..minetest.pos_to_string(advtrains.round_vector_floor_y(train.last_pos)).." is nil. block probably not loaded")
return nil
end
local nodename=node.name
if(not advtrains.is_track_and_drives_on(nodename, advtrains.all_traintypes[train.traintype].drives_on)) then
advtrains.dumppath(train.path)
print("at index "..train.index)
print("[advtrains]no track here, (fail) removing train.")
advtrains.trains[id]=nil
return false
end
if not train.last_pos_prev then
--no chance to recover
print("[advtrains]train hasn't saved last-pos_prev, removing train.")
advtrains.trains[id]=nil
return false
end
local prevnode=minetest.get_node_or_nil(advtrains.round_vector_floor_y(train.last_pos_prev))
if not prevnode then
--print("pathpredict:last_pos_prev node "..minetest.pos_to_string(advtrains.round_vector_floor_y(train.last_pos_prev)).." is nil. block probably not loaded")
return nil
end
local prevnodename=prevnode.name
if(not advtrains.is_track_and_drives_on(prevnodename, advtrains.all_traintypes[train.traintype].drives_on)) then
print("[advtrains]no track at prev, (fail) removing train.")
advtrains.trains[id]=nil
return false
end
local conn1, conn2=advtrains.get_track_connections(nodename, node.param2)
train.index=(train.restore_add_index or 0)+(train.savedpos_off_track_index_offset or 0)
--restore_add_index is set by save() to prevent trains hopping to next round index. should be between -0.5 and 0.5
--savedpos_off_track_index_offset is set if train went off track. see below.
train.path={}
train.path_dist={}
train.path[0]=train.last_pos
train.path[-1]=train.last_pos_prev
train.path_dist[-1]=vector.distance(train.last_pos, train.last_pos_prev)
end
local maxn=advtrains.maxN(train.path)
while (maxn-train.index) < 2 do--pregenerate
--print("[advtrains]maxn conway for ",maxn,minetest.pos_to_string(path[maxn]),maxn-1,minetest.pos_to_string(path[maxn-1]))
local conway=advtrains.conway(train.path[maxn], train.path[maxn-1], advtrains.all_traintypes[train.traintype].drives_on)
if conway then
train.path[maxn+1]=conway
train.max_index_on_track=maxn
else
--do as if nothing has happened and preceed with path
--but do not update max_index_on_track
print("over-generating path max to index "..maxn+1)
train.path[maxn+1]=vector.add(train.path[maxn], vector.subtract(train.path[maxn], train.path[maxn-1]))
end
train.path_dist[maxn]=vector.distance(train.path[maxn+1], train.path[maxn])
maxn=advtrains.maxN(train.path)
end
local minn=advtrains.minN(train.path)
while (train.index-minn) < (train.trainlen or 0) + 2 do --post_generate. has to be at least trainlen.
--print("[advtrains]minn conway for ",minn,minetest.pos_to_string(path[minn]),minn+1,minetest.pos_to_string(path[minn+1]))
local conway=advtrains.conway(train.path[minn], train.path[minn+1], advtrains.all_traintypes[train.traintype].drives_on)
if conway then
train.path[minn-1]=conway
train.min_index_on_track=minn
else
--do as if nothing has happened and preceed with path
--but do not update min_index_on_track
print("over-generating path min to index "..minn-1)
train.path[minn-1]=vector.add(train.path[minn], vector.subtract(train.path[minn], train.path[minn+1]))
end
train.path_dist[minn-1]=vector.distance(train.path[minn], train.path[minn-1])
minn=advtrains.minN(train.path)
end
if not train.min_index_on_track then train.min_index_on_track=0 end
if not train.max_index_on_track then train.max_index_on_track=0 end
--make pos/yaw available for possible recover calls
if train.max_index_on_track<train.index then --whoops, train went too far. the saved position will be the last one that lies on a track, and savedpos_off_track_index_offset will hold how far to go from here
train.savedpos_off_track_index_offset=train.index-train.max_index_on_track
train.last_pos=train.path[train.max_index_on_track]
train.last_pos_prev=train.path[train.max_index_on_track-1]
--print("train is off-track (front), last positions kept at "..minetest.pos_to_string(train.last_pos).." / "..minetest.pos_to_string(train.last_pos_prev))
elseif train.min_index_on_track+1>train.index then --whoops, train went even more far. same behavior
train.savedpos_off_track_index_offset=train.index-train.min_index_on_track
train.last_pos=train.path[train.min_index_on_track+1]
train.last_pos_prev=train.path[train.min_index_on_track]
--print("train is off-track (back), last positions kept at "..minetest.pos_to_string(train.last_pos).." / "..minetest.pos_to_string(train.last_pos_prev))
else --regular case
train.savedpos_off_track_index_offset=nil
train.last_pos=train.path[math.floor(train.index+0.5)]
train.last_pos_prev=train.path[math.floor(train.index-0.5)]
end
return train.path
end
function advtrains.get_or_create_path(id, train)
if not train.path then return advtrains.pathpredict(id, train) end
return train.path
end
function advtrains.add_wagon_to_train(wagon, train_id, index)
local train=advtrains.trains[train_id]
if index then
table.insert(train.trainparts, index, wagon.unique_id)
else
table.insert(train.trainparts, wagon.unique_id)
end
--this is not the usual case!!!
--we may set initialized because the wagon has no chance to step()
wagon.initialized=true
advtrains.update_trainpart_properties(train_id)
end
function advtrains.update_trainpart_properties(train_id, invert_flipstate)
local train=advtrains.trains[train_id]
local rel_pos=0
local count_l=0
for i, w_id in ipairs(train.trainparts) do
for _,wagon in pairs(minetest.luaentities) do
if wagon.is_wagon and wagon.initialized and wagon.unique_id==w_id then
rel_pos=rel_pos+wagon.wagon_span
wagon.train_id=train_id
wagon.pos_in_train=rel_pos
wagon.pos_in_trainparts=i
wagon.old_velocity_vector=nil
if wagon.is_locomotive then
count_l=count_l+1
end
if invert_flipstate then
wagon.wagon_flipped = not wagon.wagon_flipped
end
rel_pos=rel_pos+wagon.wagon_span
end
end
end
train.trainlen=rel_pos
train.locomotives_in_train=count_l
end
function advtrains.split_train_at_wagon(wagon)
--get train
local train=advtrains.trains[wagon.train_id]
local pos_for_new_train=advtrains.get_or_create_path(wagon.train_id, train)[math.floor((train.index or 0)-wagon.pos_in_train-0.5)]
local pos_for_new_train_prev=advtrains.get_or_create_path(wagon.train_id, train)[math.floor((train.index or 0)-wagon.pos_in_train-1.5)]
--before doing anything, check if both are rails. else do not allow
if not pos_for_new_train then
print("split_train: pos_for_new_train not set")
return false
end
local node=minetest.get_node_or_nil(advtrains.round_vector_floor_y(pos_for_new_train))
if not node then
print("split_train: pos_for_new_train node "..minetest.pos_to_string(advtrains.round_vector_floor_y(pos_for_new_train)).." is nil. block probably not loaded")
return nil
end
local nodename=node.name
if(not advtrains.is_track_and_drives_on(nodename, advtrains.all_traintypes[train.traintype].drives_on)) then
print("split_train: pos_for_new_train "..minetest.pos_to_string(advtrains.round_vector_floor_y(pos_for_new_train_prev)).." is not a rail")
return false
end
if not train.last_pos_prev then
print("split_train: pos_for_new_train_prev not set")
return false
end
local prevnode=minetest.get_node_or_nil(advtrains.round_vector_floor_y(pos_for_new_train_prev))
if not node then
print("split_train: pos_for_new_train_prev node "..minetest.pos_to_string(advtrains.round_vector_floor_y(pos_for_new_train_prev)).." is nil. block probably not loaded")
return false
end
local prevnodename=prevnode.name
if(not advtrains.is_track_and_drives_on(prevnodename, advtrains.all_traintypes[train.traintype].drives_on)) then
print("split_train: pos_for_new_train_prev "..minetest.pos_to_string(advtrains.round_vector_floor_y(pos_for_new_train_prev)).." is not a rail")
return false
end
--create subtrain
local newtrain_id=advtrains.create_new_train_at(pos_for_new_train, pos_for_new_train_prev, train.traintype)
local newtrain=advtrains.trains[newtrain_id]
--insert all wagons to new train
for k,v in ipairs(train.trainparts) do
if k>=wagon.pos_in_trainparts then
table.insert(newtrain.trainparts, v)
train.trainparts[k]=nil
end
end
--update train parts
advtrains.update_trainpart_properties(wagon.train_id)--atm it still is the desierd id.
advtrains.update_trainpart_properties(newtrain_id)
train.tarvelocity=0
newtrain.velocity=train.velocity
newtrain.tarvelocity=0
end
--there are 4 cases:
--1/2. F<->R F<->R regular, put second train behind first
--->frontpos of first train will match backpos of second
--3. F<->R R<->F flip one of these trains, take the other as new train
--->backpos's will match
--4. R<->F F<->R flip one of these trains and take it as new parent
--->frontpos's will match
function advtrains.try_connect_trains(id1, id2)
local train1=advtrains.trains[id1]
local train2=advtrains.trains[id2]
if not train1 or not train2 then return end
if not train1.path or not train2.path then return end
if train1.traintype~=train2.traintype then
--TODO implement collision without connection
return
end
if #train1.trainparts==0 or #train2.trainparts==0 then return end
local frontpos1=train1.path[math.floor(train1.index+0.5)]
local backpos1=train1.path[math.floor(train1.index-(train1.trainlen or 2)+0.5)]
local frontpos2=train2.path[math.floor(train2.index+0.5)]
local backpos2=train2.path[math.floor(train2.index-(train1.trainlen or 2)+0.5)]
if not frontpos1 or not frontpos2 or not backpos1 or not backpos2 then return end
--case 1 (first train is front)
if vector.equals(frontpos2, backpos1) then
advtrains.do_connect_trains(id1, id2)
--case 2 (second train is front)
elseif vector.equals(frontpos1, backpos2) then
advtrains.do_connect_trains(id2, id1)
--case 3
elseif vector.equals(backpos2, backpos1) then
advtrains.invert_train(id2)
advtrains.do_connect_trains(id1, id2)
--case 4
elseif vector.equals(frontpos2, frontpos1) then
advtrains.invert_train(id1)
advtrains.do_connect_trains(id1, id2)
end
end
function advtrains.do_connect_trains(first_id, second_id)
local first_wagoncnt=#advtrains.trains[first_id].trainparts
local second_wagoncnt=#advtrains.trains[second_id].trainparts
for _,v in ipairs(advtrains.trains[second_id].trainparts) do
table.insert(advtrains.trains[first_id].trainparts, v)
end
--kick it like physics (with mass being #wagons)
local new_velocity=((advtrains.trains[first_id].velocity*first_wagoncnt)+(advtrains.trains[second_id].velocity*second_wagoncnt))/(first_wagoncnt+second_wagoncnt)
advtrains.trains[second_id]=nil
advtrains.update_trainpart_properties(first_id)
advtrains.trains[first_id].velocity=new_velocity
advtrains.trains[first_id].tarvelocity=0
end
function advtrains.invert_train(train_id)
local train=advtrains.trains[train_id]
local old_path=advtrains.get_or_create_path(train_id, train)
train.path={}
train.index=-train.index+train.trainlen
train.velocity=-train.velocity
train.tarvelocity=-train.tarvelocity
for k,v in pairs(old_path) do
train.path[-k]=v
end
local old_trainparts=train.trainparts
train.trainparts={}
for k,v in ipairs(old_trainparts) do
table.insert(train.trainparts, 1, v)--notice insertion at first place
end
advtrains.update_trainpart_properties(train_id, true)
end
function advtrains.is_train_at_pos(pos)
--print("istrainat: pos "..minetest.pos_to_string(pos))
local checked_trains={}
local objrefs=minetest.get_objects_inside_radius(pos, 2)
for _,v in pairs(objrefs) do
local le=v:get_luaentity()
if le and le.is_wagon and le.initialized and le.train_id and not checked_trains[le.train_id] then
--print("istrainat: checking "..le.train_id)
checked_trains[le.train_id]=true
local path=advtrains.get_or_create_path(le.train_id, le:train())
if path then
--print("has path")
for i=math.floor(le:train().index-le:train().trainlen+0.5),math.floor(le:train().index+0.5) do
if path[i] then
--print("has pathitem "..i.." "..minetest.pos_to_string(path[i]))
if vector.equals(advtrains.round_vector_floor_y(path[i]), pos) then
return true
end
end
end
end
end
end
return false
end
function advtrains.invalidate_all_paths()
--print("invalidating all paths")
for k,v in pairs(advtrains.trains) do
if v.index then
v.restore_add_index=v.index-math.floor(v.index+0.5)
end
v.path=nil
v.index=nil
v.min_index_on_track=nil
v.max_index_on_track=nil
end
end