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warrenup
November 8th, 2011, 11:14 AM
I am in the process of building a four track New Haven route - my first - and have run into a problem with bridges. Bridges as splines are no problem - but I am struggling with bascule bridges as objects. The discussions I have been able to find focus on spline bridges. When I "get spline" I get a good reading but "apply spline" does not seem to function - probably because they are objects. Can anyone point be to a good explanation on how to properly install bridges as objects?
Thanks

mjolnir
November 8th, 2011, 11:39 AM
Generally, to use rail splines with object bridges, lay the spline with spline points on either side of the bridge, and place the bridge under it, using the elevation tool to raise the bridge to the proper height. Alternatively, I believe some of the fixed length bridges have built in track, and attachment points so that you can attach your track to the ends of the bridge.

For a more specific answer, you'd need to provide the KUID numbers of the bridge(s) and track splines used.

warrenup
November 8th, 2011, 06:17 PM
I am using HP track wood kuid:46162:38052 with the Bascule Lift Bridge
kuid2:60238:27201:2
When I try to adjust the bridge object, get a msg saying "object does not allow height change"

deighton
November 15th, 2011, 09:09 PM
It seems that the default for the lift bridge is "open", which means "closed" for trains. The train has to be at a certain distance to the bridge for it to close. Is there any way of changing the default so that the bridge is always closed to shipping, but open for the train to cross?

CD

big_b
November 15th, 2011, 09:26 PM
I am using HP track wood kuid:46162:38052 with the Bascule Lift Bridge
kuid2:60238:27201:2
When I try to adjust the bridge object, get a msg saying "object does not allow height change"

The height of the bridge is set to given height above the ground under it.
Looking down from above the bridge can be raised or lowered by raising /lowering the ground below the centre of the span ( use the smallest circle radius )

Dave

bendorsey
November 16th, 2011, 10:52 AM
The height of the bridge is set to given height above the ground under it.
Looking down from above the bridge can be raised or lowered by raising /lowering the ground below the centre of the span ( use the smallest circle radius )

Dave

Only the original content creator can change a bridge from normally open to normally closed. Its part of the animation.

Animated bridges are done as mocrossings so they can take advantage of code built into Trainz to operate them (no script file needed). They trigger at about 80 meters from the outer track attachment points. Extra track attachment points are necessary on very long bridges since the train could run out of the 80 meter radius causing the bridge to open back up while still on it. It won't derail as all trains cross animated bridges on invisible track but it would look pretty darn silly, lol. By adding extra track attachment points the train is always within the radius of at least one thus keeping the bridge closed until the train has crossed.

Most of my bridges are done as normally open and close at the approach of a train but a few are done as normally closed and open at the approach of a boat setup as a locomotive running on invisible track in the water.

Ben

vulcan
November 16th, 2011, 06:00 PM
A few comments:

My bascule bridges are Mocrossing objects (an older model Kind), which are not height adjustable as newer scenery models now are. As mentioned, you need to adjust the ground level in the centre of the bridge to change the height.

As Ben said, most bridges are in the open position, and the Mocrossing object triggers the closing when a trian approaches, if I recall the fixed trigger radius for a Mocrossing is something like 600 metres, so you need to adjust train speed to allow the span to come down before the train crosses.

While a creator can make the bridge be normally down (reversing the animation), the train will trigger it to open as it approaches, a defaut behaviour of a Mocrossing, so you would be presented with a raised bridge when the train approaches.

A creator can make it to be operated by ships on invisible track below the bridge triggering the normally down span to go up, and the rail track would be laid separately by the user over the bridge, in order not to trigger the animation by trains. This would require invisible track across the lift span.

The problem with this approach is that if the bridge is up, the train will not stop at the open bridge - the separately placed track is not part of the Mocrossing. There are ways to make a train track and ship track interact using track triggers, or Boat's ATLS models, but it can be a bit complicated for most users.

If you are making a fixed bridge object, no triggered animation, you should make it as a Kind Buildable, this allows height adjustment and having attached track on the object.

Ian

deighton
November 16th, 2011, 08:51 PM
Hi,

Thanks for the reply. The way I went about it is as follows: I connected an invisible track to the main track just before the bridge. I did that on both sides. On this invisble track I placed a "train". In this case a pushback tractor. The switch is defaulted to the "siding" with the pushbacktractor so that the bridge is closed for ship. This works fine, unless there are two trains approaching the bridge at the same time, in which case of course the switches are "go" for the trains and the bridge opens. Reality is very hard to simulate!!! oh yes, to hide that funny looking pushback tractor, I just put a building on top of it, or just plainly hid it underground.

CD

angelah
November 18th, 2011, 05:47 AM
Yes, I have used this bridge in the past and it is correct that it can be raised or lower by altering the ground level beneath the centre point.

The other thing I did with it was to use the ATLS crossing command objects so I could get the bridge to open earlier than the 80 metre circle.
Can't remember which route that was in, maybe Overhills.

Angela

deighton
November 18th, 2011, 10:21 AM
Hi,

The ATLS command thingamadingy, is that available on DLS?

CD

itareus
November 18th, 2011, 12:55 PM
...The ATLS command thingamadingy, is that available on DLS?...

Yes it is all on the DLS and full tutorials can be found here: http://www.boatztrainz.co.uk/tutorials.htm

It was originally designed for controlling traffic lights but has been extended to cover other things !

sniper297
November 18th, 2011, 01:21 PM
Kind Mocrossing is still used, to allow height adjustment you merely need to add one line.

kind "mocrossing"
type "Bridges"
height-range -100,100
light 1