diff options
Diffstat (limited to 'advtrains/lzb.lua')
| -rw-r--r-- | advtrains/lzb.lua | 60 |
1 files changed, 47 insertions, 13 deletions
diff --git a/advtrains/lzb.lua b/advtrains/lzb.lua index 706f825..c4b3a27 100644 --- a/advtrains/lzb.lua +++ b/advtrains/lzb.lua @@ -18,13 +18,22 @@ train.lzb = { -- Table of custom data filled in by approach callbacks -- Whenever an approach callback inserts an LZB checkpoint with changed lzbdata, -- all consecutive approach callbacks will see these passed as lzbdata table. + + udata = arbitrary user data, no official way to retrieve (do not use) } trav_lzbdata = currently active lzbdata table at traverser index } -each step, for every item in "oncoming", we need to determine the location to start braking (+ some safety margin) -and, if we passed this point for at least one of the items, initiate brake. -When speed has dropped below, say 3, decrease the margin to zero, so that trains actually stop at the signal IP. -The spd variable and travsht need to be updated on every aspect change. it's probably best to reset everything when any aspect changes +The LZB subsystem keeps track of "checkpoints" the train will pass in the future, and has two main tasks: +1. run approach callbacks, and run callbacks when passing LZB checkpoints +2. keep track of the permitted speed at checkpoints, and make sure that the train brakes accordingly +To perform 2, it populates the train.path_speed table which is handled along with the path subsystem. +This table is used in trainlogic.lua/train_step_b() and applied to the velocity calculations. + +Note: in contrast to node enter callbacks, which are called when the train passes the .5 index mark, LZB callbacks are executed on passing the .0 index mark! +If an LZB checkpoint has speed 0, the train will still enter the node (the enter callback will be called), but will stop at the 0.9 index mark (for details, see SLOW_APPROACH in trainlogic.lua) + +The start point for the LZB traverser (and thus the first node that will receive an approach callback) is floor(train.index) + 1. This means, once the LZB checkpoint callback has fired, +this path node will not receive any further approach callbacks for the same approach situation ]] @@ -61,6 +70,7 @@ local function resolve_latest_lzbdata(ckp, index) return ckpi.lzbdata end end + return {} end local function look_ahead(id, train) @@ -75,9 +85,11 @@ local function look_ahead(id, train) local lzb = train.lzb local trav = lzb.trav_index -- retrieve latest lzbdata - local lzbdata = lzb.trav_lzbdata - - if lzbdata.off_track then + if not lzb.trav_lzbdata then + lzb.trav_lzbdata = resolve_latest_lzbdata(lzb.checkpoints, trav) + end + + if lzb.trav_lzbdata.off_track then --previous position was off track, do not scan any further end @@ -85,8 +97,8 @@ local function look_ahead(id, train) local pos = advtrains.path_get(train, trav) -- check offtrack if trav - 1 == train.path_trk_f then - lzbdata.off_track = true - advtrains.lzb_add_checkpoint(train, trav - 1, 0, nil, lzbdata) + lzb.trav_lzbdata.off_track = true + advtrains.lzb_add_checkpoint(train, trav - 1, 0, nil, lzb.trav_lzbdata) else -- run callbacks -- Note: those callbacks are defined in trainlogic.lua for consistency with the other node callbacks @@ -101,6 +113,27 @@ local function look_ahead(id, train) end +local function call_runover_callbacks(id, train) + if not train.lzb then return end + + local i = 1 + local idx = atfloor(train.index) + local ckp = train.lzb.checkpoints + while ckp[i] do + if ckp[i].index <= idx then + -- call callback + local it = ckp[i] + if it.callback then + it.callback(it.pos, id, train, it.index, it.speed, train.lzb.lzbdata) + end + -- note: lzbdata is always defined as look_ahead was called before + table.remove(ckp, i) + else + i = i + 1 + end + end +end + -- Flood-fills train.path_speed, based on this checkpoint local function apply_checkpoint_to_path(train, checkpoint) if not checkpoint.speed then @@ -145,8 +178,7 @@ s = v0 * ------- + - * | ------- | = ----------- -- Removes all LZB checkpoints and restarts the traverser at the current train index function advtrains.lzb_invalidate(train) train.lzb = { - trav_index = atround(train.index), - trav_lzbdata = {}, + trav_index = atfloor(train.index) + 1, checkpoints = {}, } end @@ -175,7 +207,8 @@ end -- Add LZB control point -- lzbdata: If you modify lzbdata in an approach callback, you MUST add a checkpoint AND pass the (modified) lzbdata into it. -- If you DON'T modify lzbdata, you MUST pass nil as lzbdata. Always modify the lzbdata table in place, never overwrite it! -function advtrains.lzb_add_checkpoint(train, index, speed, callback, lzbdata) +-- udata: user-defined data, do not use externally +function advtrains.lzb_add_checkpoint(train, index, speed, callback, lzbdata, udata) local lzb = train.lzb local pos = advtrains.path_get(train, index) local lzbdata_c = nil @@ -190,6 +223,7 @@ function advtrains.lzb_add_checkpoint(train, index, speed, callback, lzbdata) speed = speed, callback = callback, lzbdata = lzbdata_c, + udata = udata, } table.insert(lzb.checkpoints, ckp) @@ -212,5 +246,5 @@ advtrains.te_register_on_update(function(id, train) return end look_ahead(id, train) - --apply_control(id, train) + call_runover_callbacks(id, train) end, true) |