This tutorial will hopefully explain how the func_train rotating
entity works in KP. It's a pretty complicated entity, but I will try my best to
explain it :)
Firstly, you are not limited to 1 train per map. The map I'm
currently building has 2 func_train rotating entities in it, plus an normal
'straight line' train, and it runs no problem. Now, down to the nitty-gritty:
First, you must build your carriage. This can be any size or shape you want,
just make sure it isn't too big(long/wide), to fit around any corners you make.
In the horizontal plane, this entity will not make a sharp 90 degree turn,(well,
it actually will, but it can't look very realistic) it looks better going around
nice round corners that aren't too sharp, which is why you have to make sure the
carriage size will look realistic as it takes the turn, especially if going thru
a tunnel... too long, and both ends of the carriage will disappear into the
walls as it goes around the curve.
Ok, once you have built your carriage, put an origin brush
in the center of it, both horizontally and vertically. This brush should be big
enough to enclose a path_corner, no bigger. Now you can select all the brushes
that make up your carriage, plus the origin brush, and make them a func_train
rotating. Yeeehaaaw!! Well, no, not really...that was the easy bit.
If you're building a single carriage train, target the train to
the first path_corner in your route(starting point), which is in turn targeted
as normal to the next path_corner etc.Note: The
train will spawn with the origin brush over the path corner, so all your
path_corners should be at the height and position of your origin brush, i.e.
center of the track, not based on the bottom left hand corner of your carriage
like in a 'normal' train. Then it's just a matter of targeting your path corners
as normal to define the route the train takes.
If you are building a multiple carriage train, then in addition to
the above, place a path_corner inside the origin brush. This is totally separate
from the path_corners defining your route; these are used to join the carriages
together into one train. Each pathcorner in each carriage you make, targets
the path corner in the next carriage, starting from the back of the train.
Only the path corner in the front carriage (loco) targets the spawn point path
corner. Also, each func_train rotating(carriage)is part of a team. So,
the keys for each of your carriages would be: Target=(pathcorner inside)
dmg=(whatever; default=2) noise=(train noise) team=(team name). All of the train
carriages including the loco must be part of the same team.
Now the complicated stuff...The path corners that you use both in
the carriage and over the track have 4 key values:Target, Targetname, Rotate,
and Speed. (There is also a key named 'reactdelay', but I'll touch on that
later). First the carriage pathcorner(multiple carriage trains only):
Target and Targetname are obvious: Target=where the train is going to
spawn(loco only-all other carriages target the next carriage, starting from
the back of the train); Targetname is what the carriage (func_train
rotating) is targetting. Speed=start speed (fiddle with this until you get what
you want..220 is a good starting speed, depending again on how big your train
is) and Rotate= rotation in the x y z planes. I don't think you have to use the
rotate key in the pathcorner inside you carriage, I'm pretty sure this is only
used in the path corners outlining the train route. I put the key in my carriage
path corner, and just left it all at 0... i.e. rotate= 0 0 0 This determines
which way the carriage is going to turn (rotate), and is used in the path
corners you place around your map. The increment used in the game is 2.5, so
that's what I used in my map. eg: rotate=0 0 2.5 - 0 rotation in the x plane, 0
rotation in the y plane, and 2.5 rotation in the z plane.
Putting a minus sign(-) in front of any of these will simply
reverse the direction of the rotation. You MUST put all three numbers in. So, if
your carriage is going to go down a hill and straighten up again as it reaches
level ground, you would put something like this in the path corners thru which
your carriage will be moving; at the top of the hill: target = t1 targetname=t2
rotate= 0 0 2.5 speed=220; at the bottom of the hill: target = t3 targetname=t1
rotate= 0 0 -2.5 speed=220. Now the increment of 2.5 is not enough to turn the
train much, so you have to keep your path corners close together when it comes
to rotation points, in fact you should butt them together with the same settings
until the rotation you desire is achieved, at which point your next path corner
will have a rotation of 0 0 0 so your train will hold that angle until you want
it to rotate back again. This is also where the speed factor is important; if
your train is moving too fast, it won't look right, or have time to complete the
rotation before it is out of the corner, so understand you have to do a lot of
trial and error. There are too many variables possible to pinpoint exactly how
much and how fast: length of corner, speed of train, steepness of grade etc, so
you gotta fiddle around with this until you find a happy medium to suit your
particular map. Confused yet? I promise to put a sample map up here as soon as I
get the time.
I noticed in the original game train that every 2nd carriage had
the reactdelay=2.5 key, but I have no idea what it does, so I put it mine just
in case :) You must also enter the same line:reactdelay=2.5 and the train speed
into the worldspawn settings. Once again I'm not sure why, but it works, so what
the hell..
So there you have it. This is a very difficult entity to explain
in words, so I will try to get a sample map up here soon. Just remember, that to
go around a corner or down/up a hill, don't make the bend too sharp, and keep
your pathcorners close together around/over the bend, and make sure the last
pathcorner has no rotation set before sending the train down the track after
completing the turn, because it will just keep on rotating as it goes if you
don't tell it to stop. I've also had trouble riding on one of these as they go
thru a turn, so I'm not sure if that is possible with this entity.
Download the tutorial source .map files from here.
