The International Simutrans Forum

PakSets and Customization => Pak128.Britain => Topic started by: The Hood on December 10, 2011, 10:31:24 AM

Title: Bridges
Post by: The Hood on December 10, 2011, 10:31:24 AM
As we are very short on bridges I'm going to try and fill that gap next.  At the minute I'm proposing the following types for immediate attention:
Plate Girder e.g. http://www.newrailwaymodellers.co.uk/images/bridges/large/boughton1.jpg (http://www.newrailwaymodellers.co.uk/images/bridges/large/boughton1.jpg) (done)
Truss e.g. http://www.flickr.com/photos/4737carlin/2406455006/in/gallery-tom-swailes-72157622846469784/ (http://www.flickr.com/photos/4737carlin/2406455006/in/gallery-tom-swailes-72157622846469784/)
Concrete viaduct (elevated way version as well) e.g. http://www.flickr.com/photos/hamishfenton/4471109766/ (http://www.flickr.com/photos/hamishfenton/4471109766/)
Wrought Iron arch bridge e.g. http://www.london-traveltips.com/pics/blackfriars-bridge-st-pauls-cathedral.jpg (http://www.london-traveltips.com/pics/blackfriars-bridge-st-pauls-cathedral.jpg)
Wrought iron viaduct (elevated way version as well) e.g. http://adriadavidson.com/blog/wp-content/uploads/2011/01/georges_dock_building.jpg (http://adriadavidson.com/blog/wp-content/uploads/2011/01/georges_dock_building.jpg)
Wrought iron trestle (see below)
Wooden viaduct e.g. en.wikipedia.org/wiki/Cornwall_Railway_viaducts

I've tried to stick to ones which will look good in simutrans (so no requests for the forth bridge please unless you plan to implement a patch to allow bridges with different images for different tiles along the length like in transport tycoon!).

If you have any thoughts about these, e.g. speeds and weight limits, or any other good designs to try, post here.  I'll also keep updates here as and when they happen.

EDIT: first preview: plate girder railway bridge (only a preview; needs snow, and pillars for longer versions as well as some sensible data).  I've reused most of the brick viaduct sprites for the approaches and the only new images are for the spans themselves; I think it looks OK but I'd be interested to see if others agree.

(http://img839.imageshack.us/img839/2677/plategirderpreview.jpg) (http://imageshack.us/photo/my-images/839/plategirderpreview.jpg/)
Title: Re: Bridges
Post by: jamespetts on December 10, 2011, 11:48:25 AM
Excellent! Just what we needed. Incidentally, I suggest that you look at some of the bridges in the Experimental version, which define bridge types along with various limits, relative costs, etc., albeit have no graphics - if you want ideas as to bridge types, you could do worse than to look there. (I notice that many of your types fit in more or less with those types in any event).

As to the plate girder bridge, why don't you make two versions - one that can only span one or two tiles (perhaps in a different colour) and one that can be longer, with pillars? You could make the shorter type cheaper per tile: see the various Experimental bridges (without their own graphics) for an idea as to what I mean. In any event, however, that bridge does look lovely.
Title: Re: Bridges
Post by: The Hood on December 10, 2011, 12:12:30 PM
To be honest James I'm no civil engineer and I can't quite relate the descriptions in experimental to what they are supposed to look like.  If you could post pictures of what each is supposed to look like that would be good. 

Secondly there is no need I can see for two versions of the bridge with and without pillars; I am planning on making the pillar distance 2 tiles so 1-2 tile bridges wouldn't get pillars anyway.
Title: Re: Bridges
Post by: jamespetts on December 10, 2011, 12:43:46 PM
Will try to have a go when I can - am a bit busy to-day having a tea party...
Title: Re: Bridges
Post by: AP on December 10, 2011, 03:36:27 PM
Quote
EDIT: first preview: plate girder railway bridge
Looks good!

Can I suggest a wrought iron trestle/truss type? It's quite an important early design, and about the only one which could be used for overly tall viaducts. At present we have a vaguely-American wooden trestle, which can be built tall, but that looks a bit odd (and is very slow). With metal truss  bridges, the piers just extend which is how simultrans seems to handle such things (not sure if the taper is possible). For those of us who like hilly maps it'd be rather an improvement.

The classic UK precedents are Belah and Crumlin viaduct (1850s) and Meldon viaduct (1870s). EDIT: Google throws up some less lofty versions of the design e.g. Bennerley (http://en.wikipedia.org/wiki/Bennerley_Viaduct).
(http://www.forgottenrelics.co.uk/bridges/images/belah/belah-1.jpg)
(http://www.ssplprints.com/lowres/43/main/46/125546.jpg)
(http://www.meldonviaduct.co.uk/images/sm_l_viaduct_old.jpg)
Title: Re: Bridges
Post by: The Hood on December 10, 2011, 04:06:46 PM
Good suggestions AP, I've ammended the first post.  I'll do those all as a single type of iron trestle viaduct.  Any reason why you removed the link to the cornish trestle viaducts?
Title: Re: Bridges
Post by: AP on December 10, 2011, 04:11:20 PM
Heh, you're clearly too quick for me.  I removed my Brunel's Cornish viaducts (http://upload.wikimedia.org/wikipedia/commons/8/8d/Carvedras_Viaduct.jpg) comment it because I saw your perfectly fair remark about the Forth bridge, and thought they might be similarly a bit more complex. Also because they're not that 'flat' - ie they only work if they are sufficiently tall to allow the 'fan', and I wasn't sure Simutrans could handle that. Although now I think about it, the game handles arches okay, so perhaps...
Title: Re: Bridges
Post by: The Hood on December 10, 2011, 04:25:53 PM
I would make the fans the same height as the arches currently, with pillars making up the rest - we'll see if it looks good.
Title: Re: Bridges
Post by: AP on December 10, 2011, 05:18:26 PM
It would certainly be great to get them in-game - they were both quite distinctive visually and economically - low initial outlay but higher ongoing maintenance costs - hence they were all replaced later on. That's certainly something which could make them useful in-game (as in reality).
Title: Re: Bridges
Post by: greenling on December 10, 2011, 07:40:37 PM
The Photos From the Old Bridge be Very Nice.
Thumbs UP!
Title: Re: Bridges
Post by: jamespetts on December 11, 2011, 03:57:53 PM
Some pictures for the various bridge types in Experimental without graphics:

1. Short steel girder (will suffice for heavy/light versions - perhaps different colours for each):

(http://bigatoll.com/girderbridge.jpg)

2. Light box girder:

(http://www.euromodeltrains.com/trains/products/vollmer/images/small/7801.jpg)

3. Normal box girder:

(http://www.rocotrains.ca/cart/images/40080.jpeg)

4. Supported Steel Lattice Bridge

This is the same type as AP has identified above

5. Cantilever

This is the forth bridge type that you consider too difficult

6. Suspension bridges (various)

Many, but see, for example:

(http://www.ikbrunel.org.uk/userFiles/suspension-bridge.jpg)

7. Concrete spanning bridge (various light/heavy, etc.)

(http://mytrainmaster.files.wordpress.com/2011/11/img_4361.jpg)

8. Concrete supported bridge (various light/heavy, etc.)

(http://www.newcrossing.gov.bm/photo-library/images/WatfordBridge.jpg)

We could probably also do with a bridge like this crescent bridge:

(http://www.newrailwaymodellers.co.uk/images/bridges/peterborough.jpg)
Title: Re: Bridges
Post by: The Hood on December 11, 2011, 08:18:46 PM
Latest update: snow version and road version complete:

(http://img248.imageshack.us/img248/8594/roadgirderbridge.jpg) (http://imageshack.us/photo/my-images/248/roadgirderbridge.jpg/)

Regarding the above James, most should be possible (although the suspension bridge also falls into the same category as the cantilever - not that it's too difficult to draw but that simutrans doesn't support "long" bridges which aren't made up of repeating 1x1 tiles).  The last two look essentially the same though (just one has intermediate pillars).
Title: Re: Bridges
Post by: The Hood on December 12, 2011, 10:23:16 PM
Preview: steel truss bridge.  I'm planning on doing new approach sprites for these.  What do we think about player colours?  Worth it?  Should I do player colours for the plate girder too?

(http://img705.imageshack.us/img705/8191/playercolourtruss.png) (http://imageshack.us/photo/my-images/705/playercolourtruss.png/)
Title: Re: Bridges
Post by: sdog on December 12, 2011, 10:27:40 PM
the pak-britain player colours are very well chosed, they look excellent with steel latices.
Title: Re: Bridges
Post by: jamespetts on December 13, 2011, 01:15:06 AM
Very nice!
Title: Re: Bridges
Post by: AP on December 14, 2011, 09:36:58 PM
I think they're maybe a bit garish in player-colours. Could perhaps just the bottom rails, or top rails, be player coloured, and the rest a battleship grey? (I'd say red-oxide but that maybe a player colour!). I mean, FGW may have purple trains but their bridges are definitely not!

Another suggestion - we need a flat bridge - that is a bridge for rail (and road) to cross water on-the-level. The ideal might be that a swing bridge (or bascule bridge) evolves into a more modern interpretation at some c20th date. A swing bridge needs an island, of course, I can't recall if river traffic works like roads, left and right sides, or not...

Swing Bridge, Norfolk (there's a nice one in Newcastle too, but it's a bit bigger).
(http://www.constructionphotography.com/ImageThumbs/A037-00036/3/A037-00036_Swing_bridge_Norfolk_United_Kingdom.jpg)

I recall being told it's not possible to vary a crossing type with a timeline, but presumably it's done with level crossings - gates become barriers at some point I assume? If so, in pak.128 is a lift bridge like the kingsferry bridge on the isle of sheppy. We could use that as the later one?
(http://upload.wikimedia.org/wikipedia/commons/e/ee/Kingsferry_Bridge_-_geograph.org.uk_-_4251.jpg)

The alternative, of course, perfectly realistic, is to have a single flat crossing, which does not allow water craft to pass - that is, a fixed short bridge which deliberately obstructs navigation. Which would force the use of 'better', higher bridges to cross water - the sort of dilemma which faced real engineers and led, for example, the GWR not to build a railway line to Dartmouth (since they'd have needed another Saltash-type bridge) and go to Kingswear instead.

e.g. a bridge like this:
(http://farm4.static.flickr.com/3242/2353886705_0bc0fd4f30.jpg)
Title: Re: Bridges
Post by: The Hood on December 14, 2011, 10:28:14 PM
Timelines are now available for crossings, hence the various barriers in pak128.Britain.  I will ultimately add various crossings like these too.

Re player colours I was probably erring towards having them as they didn't look too bad to me.  I'd be interested on other views though, as I don't ever play the game so I'm never really bothered about player colour issues, but I'm told it's important for multiplayer...
Title: Re: Bridges
Post by: AP on December 14, 2011, 10:56:25 PM
Timelines are now available for crossings
Cool. For completeness, perhaps a bascule bridge might be useful too, especiall for the 1750-1830 sort of era. Would work for road and early rail, if designed correctly.
(http://www.sciencephoto.com/image/352920/530wm/T6070011-Barge_passing_under_a_manually_raised_bridge-SPL.jpg)

I'm told it's important for multiplayer...
Useful, in that it saves using the magnifying glass tool, not sure about important - not for bridges. Definitely important for vehicles and stations- the things one interacts with. But I think it's important it's tasteful, pak.gb is one of the better-looking paks, and multicoloured bridges could upset the visual cohesion. Same arguement goes for over-all roofs on the big stations - purple railings and lamp posts are subtle, massive purple roofs less so. But that's just my view.

Title: Re: Bridges
Post by: jamespetts on December 15, 2011, 12:47:45 AM
I'm not sure that water crossings are a good idea, as they detract from the need to build proper bridges.
Title: Re: Bridges
Post by: sdog on December 15, 2011, 01:28:35 AM
most simutrans rivers are in valleys, most of the time one wants to build proper bridges to avoid the climb up again. For the cases where a river is completely on flat terrain, they are very usefull, as a proper bridge would require that climb.

Is there a way in simutrans to define crossings with rivers only for the smaller types? Not for the widest two types of navigable rivers?


on the player colour bridges:
i wouldn't worry too much, most of those player colours look quite similar to rust protecive paints especially the light blue, rust red and green one. If i'm not mistaken, the yellow is also a colour available in 19th century. The purple and bright blue and cyan are a bit off, but players don't have to chose it if they don't like it.
Title: Re: Bridges
Post by: jamespetts on December 15, 2011, 01:33:31 AM
Is there a way in simutrans to define crossings with rivers only for the smaller types? Not for the widest two types of navigable rivers?

I suspect, alas, that this cannot be done - otherwise, it would be a useful workaround.
Title: Re: Bridges
Post by: AP on December 15, 2011, 08:37:16 AM
I'm not sure that water crossings are a good idea, as they detract from the need to build proper bridges.

Not so sure- I mean, I'm more interested in preserving level track - and thus keeping running speed high - so will always use an embankment and raised viaduct. Unless i'm building track alongside a canal, or terrain has dictated the track must be right at water level (e.g. to match levels elsewhere), when I'll cross it on the flat - which seems entirely reasonable and realistic.

If it's a gameplay worry, we could prohibit lifting bridges on that basis though - the price you pay for the flat crossing being insufficient clearance for navigation?
Title: Re: Bridges
Post by: jamespetts on December 15, 2011, 09:24:10 AM
The issue with the crossings is rather more acute with roads than rail, as gradients are lessof an issue.
Title: Re: Bridges
Post by: AP on December 15, 2011, 09:53:59 AM
The issue with the crossings is rather more acute with roads than rail, as gradients are lessof an issue.
Not unrealistic, though - it's normal to build a road down a valley, a small bridge over the water, and up the other side (unless you're building the Millau Bridge).

If it's a gameplay concern, presumably including flat rail crossings whilst prohibiting flat road crossings would be considered somewhat unfair? I wonder if we could use speed limits to mitigate? As in, put a 30mph speed limit on all lifting bridges...
Title: Re: Bridges
Post by: The Hood on December 15, 2011, 03:54:11 PM
Another option with water/road bridges is to make the water speed = 0, i.e. un-navigable.  This would represent low bridges boats could not fit under.  That said there may be a gameplay concern in multiplayer here if player A is using rivers to transport stuff and player B builds a bridge over the river and blocks it...
Title: Re: Bridges
Post by: AP on December 15, 2011, 03:57:26 PM
 
Quote
if player A is using rivers to transport stuff and player B builds a bridge over the river and blocks it
Heh, but that goes on anyway. On the pak-gb online game, one of the players used the raise-land tool to block another player's oil tankers. But that game had no moderator/rules - with a decent moderator it wouldn't happen. There are plenty of ways to disrupt other players if you're creative about it... traffic light frequencies, slow buses... ;)

The 0 speed limit is interesting though. Even if the bridge opens, the speed limit through the open span should still be very low.
Title: Re: Bridges
Post by: AP on December 15, 2011, 04:15:12 PM
7. Concrete spanning bridge (various light/heavy, etc.)


That's a model!!  :P Not convinced about the structural proportions of it either, unless there's a concrete downstand beam hidden underneath... just sayin'!
Title: Re: Bridges
Post by: jamespetts on December 15, 2011, 04:47:21 PM
One of the main problems with these crossings is that they cost the same as a basic road (etc.), whereas proper bridges cost much more: this causes economic distortions.
Title: Re: Bridges
Post by: AP on December 15, 2011, 05:05:39 PM
One of the main problems with these crossings is that they cost the same as a basic road (etc.)
Could that not be fixed globally? Make them the same as a higher-spec road/rail tile instead?
Title: Re: Bridges
Post by: VS on December 15, 2011, 05:12:07 PM
Since crossings are selected and built fully automatically, these costs would have to be made transparent. (just saying...)
Title: Re: Bridges
Post by: sdog on December 15, 2011, 05:41:44 PM
Player B could as well just bulldoze the river.
It has to be clear in a way, so fair player can avoid it. At last resort, there is always communication in game. I think you shouldn't worry too much, it seems most online players now are very polite and cooperative.
Title: Re: Bridges
Post by: ӔO on December 15, 2011, 10:38:32 PM
To be honest James I'm no civil engineer and I can't quite relate the descriptions in experimental to what they are supposed to look like.  If you could post pictures of what each is supposed to look like that would be good. 

Secondly there is no need I can see for two versions of the bridge with and without pillars; I am planning on making the pillar distance 2 tiles so 1-2 tile bridges wouldn't get pillars anyway.
@james, hood

here's a bunch I've accumulated for design reference. I don't quite recall where I've gotten them from.
I've mainly narrowed them down to ones that can be drawn for simutrans, but there are still quite a few parts on some of those bridges that just can't be drawn in because the pillars are a single repeating image. That is, unless height is restricted so you only get one pillar height.
http://dl.dropbox.com/u/17111233/Bridge_Ref.rar (http://dl.dropbox.com/u/17111233/Bridge_Ref.rar)
Title: Re: Bridges
Post by: The Hood on December 16, 2011, 09:56:41 AM
Thanks for those ideas AEO.  I will try and condense them into styles I think look good in simutrans and idealise them slightly to get round the issues of repeating tiles.  I really do wish we could have multi-tile bridges like in OTTD!

I take it no further opinions on player colour bridges then?  I might try a demo version of the bridges with (a) no player colour (b) subtle player colour highlights (c) all over player colour. 

EDIT:

I've just stumbled upon this (http://forum.simutrans.com/index.php?topic=2398.0) again, not sure how I managed to miss it!  Did you ever get any further with any of these parts AEO?  Seeing as there is a lot of good stuff here I'd love to use it, but I think there are some consistency issues that would need resolving e.g. consistency of tracks.  I could try importing these into blender to resolve or cutting and pasting track graphics in gimp.

For blender I would need them as Collada .dae files, and for gimp obviously I'd need the rendered images as pngs.
Title: Re: Bridges
Post by: AP on December 16, 2011, 01:40:58 PM
Player B could as well just bulldoze the river.
I always thought that ought to be fixed...
Title: Re: Bridges
Post by: The Hood on December 16, 2011, 04:38:38 PM
Using the png files in the previously linked thread I've managed to adapt AEO's tubular bridge in GIMP to use consistent tracks with the rest of the pak.  Here's the result:

(http://img338.imageshack.us/img338/1058/tublarbridge.jpg) (http://imageshack.us/photo/my-images/338/tublarbridge.jpg/)

I'm hoping to do something similar with the beam bridge too.

Can't find sources for any other bridge parts in there - AEO do you have these?
Title: Re: Bridges
Post by: ӔO on December 16, 2011, 06:44:54 PM
I only have the sources for those bridge parts as a sketchup file. I can export them as .dae, but for some reason I can't import them into blender. That is, blender crashes.

edit1: okay, wait, I think I got it to import after exporting from meshlab.
It seems you need to export .dae from sketchup > import to meshlab > export from meshlab as .dae > import to blender


edit2: here are the side parts.
The ones that are longer or shorter than normal are done on purpose. The shorter ones are short because there should be a pillar in the empty space. The longer ones, except the 2 tile arch, should overlap slightly. The 2 tile arch is just the original to most of the arches in there.

edit3
pillars:
rail bridges with no textures:

edit 4, fixed link: http://dl.dropbox.com/u/17111233/Bridges_ver_collada.rar (http://dl.dropbox.com/u/17111233/Bridges_ver_collada.rar)
Title: Re: Bridges
Post by: The Hood on December 16, 2011, 07:44:30 PM
Hmm, that link isn't a download, it gives code instead...

I'm beginning to think it might be best if you have the parts available as png files or better as gimp xcf files as I can then add them in layers on top of existing ways/bridge decks to create a range of bridges quite easily.  It's how I've been adapting the bridges you made last year.  I had trouble making any sense of the dae file in blender anyway, all the parts seemed to be on top of each other from several different frames.

Looking back at that old thread, there's a few I'm interested in but the old images seem to have been removed: steel and concrete box girder, beam/I-beam, steel lattice, iron bridge, and of course the miscellaneous parts on the last screenshot from sketchup.

Anyway, here's the beam girder bridge:

(http://img706.imageshack.us/img706/6485/beamgirder.jpg) (http://imageshack.us/photo/my-images/706/beamgirder.jpg/)

I think it's probably best as a slower, lighter, cheaper version of the plate girder.
Title: Re: Bridges
Post by: ӔO on December 16, 2011, 08:15:55 PM
@hood
I think it might be because firefox thinks its a script?
I could make a rar version in a bit, but you can also do "save link as".

http://dl.dropbox.com/u/17111233/Bridges_ver_collada.rar
Title: Re: Bridges
Post by: greenling on December 16, 2011, 08:44:43 PM
The photos from the bridges Aeo be are great! very great!
Thumbs up! :)
Title: Re: Bridges
Post by: sdog on December 16, 2011, 10:35:21 PM
the little spec of snow on the edge of the pillars looks quite good, giving it much more depth.
Title: Re: Bridges
Post by: The Hood on December 17, 2011, 08:59:54 AM
Thanks for the dae files AEO - I can get them into blender no problem but they've lost all their colour and texture in the process.  I'm assuming you don't have correctly scaled png files for them so I can use them as GIMP layers, but even if not, they're still good to make a few different bridge types from.
Title: Re: Bridges
Post by: jamespetts on December 17, 2011, 12:42:05 PM
Looking delightful!
Title: Re: Bridges
Post by: sdog on December 17, 2011, 06:54:29 PM
do you think some of the new bridges could be convincingly retouched for pak128?
Title: Re: Bridges
Post by: The Hood on December 17, 2011, 06:59:57 PM
AEO's two bridges probably fit better into pak128 in their original form, and if not it's probably a case of just changing the tracks and nothing else.  I could post the GIMP files for these and you could just change the layer with pak128.Britain tracks for standard pak128 track graphics?  As for the ones I did, I can upload the blend files which could then be adapted in the pak128 style.
Title: Re: Bridges
Post by: ӔO on December 17, 2011, 07:58:10 PM
oh yes, I had to remove the textures and colours, because they were not being correctly applied under meshlab.
Title: Re: Bridges
Post by: jamespetts on December 18, 2011, 02:42:24 PM
There seems to be a bug in the .dat file for the plate girder road bridge: its name is still "BrickViaductRoad". See here (https://raw.github.com/aburch/simutrans-pak128.britain/f081d0e41d401f51ec5e06764fa85640a1f2fb75/ways/plate-girder-road.dat).

Edit: On a different matter, once the concrete supported bridges have been done, it should be fairly straightforward to make an elevated way version of them, should it not?

Edit 2: I have had an idea about how to draw suspension and cantelever bridges: pillar repetition frequency can be defined, so all that needs to happen is to make all of the non-uniform part of the bridge into a pillar. So long as the graphics for pillars are allowed to pretrude beyond the tile boundary either side and the top of the bridge, it should in theory be possible to have the entire set of supports and cables for a suspension bridge (for example) defined as one pillar. I am not sure how well this would work, but worth a try, perhaps?
Title: Re: Bridges
Post by: ӔO on December 18, 2011, 04:12:53 PM
@james

I've toyed with the idea of using a larger pak size to draw large arches and suspensions, but concluded it was fairly difficult to align properly, the lengths, heights must be absolutes and pillars lack a front image for over deck pillars to be drawn correctly.

It should be possible to do this for large arches and elaborate trusses or cantilevers, but only in certain lengths. The deck will repeat itself for X tiles, so the deck must remain plain, but the ends can be enlarged so that they will touch each other graphically. I think one can get a 4 tile bridge if one uses pak192 on a pak128 environment. 6 tiles for something drawn in 256 and so on. However, they can't be shorter either, since the images won't mesh properly.

It should be possible to do this for suspensions, but it can't be any higher than 1 tile, because pillars will stack if there is more than one height. They also need a front image to be drawn correctly. It is the same idea as enlarging and extending the ends, but this time, it is only done with the pillar.
Title: Re: Bridges
Post by: wlindley on December 18, 2011, 07:32:59 PM
One "graphical hack" that might help, is that tiles are drawn in the order of closeness to the viewer; and they are not clipped at all. 

For example, a thin vertical wall aligned on the center of the tile, such that the first pixel is drawn in the very lower-left corner, would have a maximum visual dimension of 128 pixels "long" and 96 pixels "tall" in pak128; it would halfway overlap the tile to its "east" and "west" but if you arrange your building tiles carefully, you can use this to advantage.  In other words, feel free to go beyond the usual 64x64 diamond inside of pak128.  I did this in the walls for the new Tower of London graphic if you'd like to see what I mean.
Title: Re: Bridges
Post by: The Hood on December 19, 2011, 09:48:20 AM
Regarding graphical hacks for bridges the following need to be borne in mind about the current implementation:
1) the "deck" is a single repeating image along the length of the bridge - only one is allowed.
2) the pillars are a single repeating image vertically - if you tried to use this with pillar frequencies of two or more tiles, it would be fine if the bridge height is no less than a single tile, but for higher bridges it would look odd as the image would repeat below.
3) front images are not possible for pillars.

I'm struggling to see how you could get around all of these problems - the best attempt I saw was using stations to provide the bridge parts, but it was an ugly hack as it took a lot of menu space and wasn't entirely intuitive.

If we want those types of bridges a code change is probably the only decent way of doing it, and that would be of interest beyond pak128.Britain.  It must be possible as OpenTTD manages to do it (and always has).  If anyone is familiar with the code for that maybe they could try a patch?  Anyway, I suggest this discussion is continued here: http://forum.simutrans.com/index.php?topic=8788.0 as it is not related specifically to pak128.Britain. 

Use this thread to discuss pak128.Britain bridges (hopefully one or two more to follow later...)
Title: Re: Bridges
Post by: The Hood on December 19, 2011, 10:28:59 PM
Some progress - completed steel truss rail bridge.  I decided to go with player colours for now.

(http://img687.imageshack.us/img687/1844/steeltruss.jpg) (http://imageshack.us/photo/my-images/687/steeltruss.jpg/)
Title: Re: Bridges
Post by: jamespetts on December 19, 2011, 10:37:38 PM
Very nice!
Title: Re: Bridges
Post by: sdog on December 20, 2011, 03:19:45 AM
to say it in the words of another forum member: "this looks very good out!"

the new floor and end tiles of the bridge are outstanding, quite an improvement from earlier versions, and other bridges. Your masterpiece.




edit: posted it in the blog
http://blog.simutrans.com/?p=1833
Title: Re: Bridges
Post by: The Hood on December 20, 2011, 09:26:01 AM
Thanks sdog (and thanks for not hyping it up by saying "probably in the spring!".  Very vague; nice!

Probably not going to get many awards, but very functional: a simple concrete viaduct.  Essentially the modern replacement for the brick viaduct.  High speed version to come.

(http://img828.imageshack.us/img828/4379/concreteviaduct.jpg) (http://imageshack.us/photo/my-images/828/concreteviaduct.jpg/)
Title: Re: Bridges
Post by: jamespetts on December 20, 2011, 11:25:40 AM
These are most impressive.
Title: Re: Bridges
Post by: The Hood on December 20, 2011, 01:32:34 PM
And a road version of the concrete viaduct - credit here to AEO; I finished off what he started.

(http://img198.imageshack.us/img198/6674/concreteviaductroad.jpg) (http://imageshack.us/photo/my-images/198/concreteviaductroad.jpg/)

EDIT: And a high speed rail concrete viaduct:

(http://img843.imageshack.us/img843/2089/highspeedviaduct.jpg) (http://imageshack.us/photo/my-images/843/highspeedviaduct.jpg/)
Title: Re: Bridges
Post by: The Hood on December 20, 2011, 09:49:45 PM
And three more road bridges - all using AEO's parts:

1) Basic concrete beam bridge

(http://img546.imageshack.us/img546/8189/concretebeam.jpg) (http://imageshack.us/photo/my-images/546/concretebeam.jpg/)

2) Concrete deck steel truss

(http://img811.imageshack.us/img811/583/concretesteeltruss.jpg) (http://imageshack.us/photo/my-images/811/concretesteeltruss.jpg/)

3) Concrete deck steel cantilever

(http://img502.imageshack.us/img502/1669/concretesteelcantilever.jpg) (http://imageshack.us/photo/my-images/502/concretesteelcantilever.jpg/)

EDIT: All of these are now in SVN. I've removed the two fastest Brick viaducts to be replaced with the new concrete ones, but this should be taken care of in old saves via compat.tab.
Title: Re: Bridges
Post by: jamespetts on December 20, 2011, 11:16:50 PM
Splendid!
Title: Re: Bridges
Post by: ӔO on December 21, 2011, 02:06:53 AM
It's good to see those parts being put to good use by an expert :)
Title: Re: Bridges
Post by: Isaac.Eiland-Hall on December 21, 2011, 04:11:54 AM
I've been watching this thread with glee at all the beautiful bridges. :-)
Title: Re: Bridges
Post by: VS on December 21, 2011, 09:39:38 AM
I'm mostly green with envy :D
Title: Re: Bridges
Post by: ӔO on December 21, 2011, 02:40:19 PM
@hood

just two nitpicks with the names on #1 and #3.
#1 looks more like a plate girder, rather than a beam bridge. Beam bridges will have no supports showing on top or under the deck, except for the pillars.
#3 looks more like a steel through arch bridge.
Title: Re: Bridges
Post by: Milko on December 21, 2011, 03:38:10 PM
Hello

These bridges and the work done by Wlindley are a great Christmas gift .... Thanks

Giuseppe
Title: Re: Bridges
Post by: The Hood on December 21, 2011, 09:09:48 PM
just two nitpicks with the names on #1 and #3.
#1 looks more like a plate girder, rather than a beam bridge. Beam bridges will have no supports showing on top or under the deck, except for the pillars.
#3 looks more like a steel through arch bridge.

AEO, you seem to know rather a lot more about bridge nomenclature than I do.  Is there any particular logic? Seems the "common" names I'm familiar with easily confuse the deck type and the structure type etc.

These bridges and the work done by Wlindley are a great Christmas gift .... Thanks

I'm planning a pre-Christmas release with these in.  If you're really lucky, there may be some extra bridges too (depending on how much time I get in the next couple of days)
Title: Re: Bridges
Post by: Milko on December 21, 2011, 09:18:36 PM
Hello

I'm planning a pre-Christmas release with these in.  If you're really lucky, there may be some extra bridges too (depending on how much time I get in the next couple of days)

I too, if I have time, I can do a little Christmas gift to pak128brit. Maybe we will put it right in the pre-Christmas release ....

Giuseppe
Title: Re: Bridges
Post by: ӔO on December 22, 2011, 11:10:31 AM
@hood
I agree that the distinctions can become rather difficult with some bridges. To make matters worse, some are even combinations or hybrids of two or more types.
I wouldn't call myself an expert on bridges, but you are on the right track with what what supporting structures the bridge uses. (In fact I recently realized that I have gotten the rotation of the I-beams wrong on those trusses I've made. They should have the flat side facing outwards, so they have more surface area at the joints. oops :-[ )

Surprisingly, wiki has quite a comprehensive list with pictures for bridge types.
It can be a lot of info to digest, however.
http://en.wikipedia.org/wiki/List_of_bridge_types (http://en.wikipedia.org/wiki/List_of_bridge_types)

To break down the types, without getting into too much detail, I suppose some basic analysis of how it's shaped and how the load is distributed would work.

Basically, it breaks down into:
Compression - Deck keeps itself up by using its own weight. Concrete only works well in compression.
Tension - Deck is kept up with tension (suspension) from structure above it. Steel or iron is most desirable for this.
Neither - Deck is kept up by resisting forces that would otherwise bend it in half.

 Through "" bridge - The main support structure is only above deck. Works in both compression and tension.
 Half-through  "" bridge - The main support structure is both above and below deck. Works in both compression and tension.
 Deck "" bridge - Often omitted, but this means the main support structure is entirely below the deck. Mostly works in compression to keep the deck up.

Many bridges work in compression and tension. Some work only in compression. Vertical pillars obviously only have compression forces on them.
  • Arches only work in compression, but cables or beams tied below it can act in tension. It's like leaning two pillars against each other.
  • Cantilever mainly works in tension. The upper section  is in tension and holds up the ends, much like a person holding groceries with their arms. The pillars/legs are only located in the center and it must balance itself.
  • Suspensions work with strung cables in tension only. Similar in concept to cantilever.
  • Trusses work in both compression and tension, whether the structure is above or below the deck. They allow longer spans than girders and boxes alone.
  • Beams, girders and boxes simply work be resisting bending against the weight. These are very plain looking and most cannot span too far without pillars to keep them up.
Title: Re: Bridges
Post by: Lord Vetinari on December 23, 2011, 05:22:30 PM
Finally, with the vacations I can get back to Simutrans. During the holidays I'll finish the elevated way version of my bridge and post it. Great work  with the bridges in this topic, btw!

I downloaded the new version, I noticed that there is a small misalignement problem with my bridge that doesn't happen in my test pak file. Either the image file or the dat file used for the official release are not the right ones. I'll repost them, if you wish.
Title: Re: Bridges
Post by: The Hood on December 24, 2011, 09:37:10 AM
If you could repost them I will investigate.
Title: Re: Bridges
Post by: The Hood on January 03, 2012, 09:08:52 AM
Work in progress: Iron lattice girder (again courtesy of AEO's parts)

(http://img843.imageshack.us/img843/2540/ironlatticegirder.jpg) (http://imageshack.us/photo/my-images/843/ironlatticegirder.jpg/)

EDIT: now with snow too.

(http://img846.imageshack.us/img846/3686/ironlatticegirdersnow.jpg) (http://imageshack.us/photo/my-images/846/ironlatticegirdersnow.jpg/)
Title: Re: Bridges
Post by: greenling on January 03, 2012, 12:46:05 PM
THe Hood
The Brides on the photo looks great out.
It´s make the game very nice to play.
Title: Re: Bridges
Post by: jamespetts on January 03, 2012, 01:01:54 PM
Very nice!
Title: Re: Bridges
Post by: The Hood on January 03, 2012, 01:59:25 PM
And now an iron bowstring girder bridge, loosely based on Barnes Bridge and again using AEO's parts.

(http://img18.imageshack.us/img18/272/ironbowstringgirder.jpg) (http://imageshack.us/photo/my-images/18/ironbowstringgirder.jpg/)
Title: Re: Bridges
Post by: Milko on January 03, 2012, 02:15:22 PM
Hello

Superb!, you're revolutionizing the look of the pak!  :)

Giuseppe
Title: Re: Bridges
Post by: wlindley on January 03, 2012, 02:57:19 PM
Splendid!  ...the challenging part, will be picking a variety of different building-costs and operating-costs... will there some bridges that are less expensive to build, but much more expensive to maintain?
Title: Re: Bridges
Post by: jamespetts on January 03, 2012, 03:16:05 PM
Have a look at the Experimental version - there are a whole range of bridges there (albeit sharing the original bridge graphics temporarily) with different costs, weights, maximum lengths and heights.
Title: Re: Bridges
Post by: The Hood on January 03, 2012, 05:45:27 PM
And another - a wrought iron arch bridge.

(http://img860.imageshack.us/img860/6599/ironarchbridge.jpg) (http://imageshack.us/photo/my-images/860/ironarchbridge.jpg/)
Title: Re: Bridges
Post by: jamespetts on January 03, 2012, 05:51:32 PM
Splendid! I work near Blackfriars Bridge, and this is a rather wonderful reproduction.
Title: Re: Bridges
Post by: sdog on January 03, 2012, 10:04:06 PM
the wrought iron arch bridge is quite a beauty. The colour looks very similar to brick however, i'm not sure if a sliglty different colour would be possible and make it more obvious it is not a brick bridge with ornaments. That was what i was thinking at first glance, it reminded me of the Patrician's brick viaduct.

I've never seen such a iron latice bridge, i always thought they would need a lattice work on top too for static stability. Similar to tubular bridges. I don't know a lot on bridges however.
I just looked at a photo of meadowbank bridge, which looks very similar to yours. It has no lattice above, only some struts at regular intervals. Those might have been to support the catenary, if the bridge was electrified.


On height restrictions,
Title: Re: Bridges
Post by: Arkadiusz on January 04, 2012, 12:16:58 AM
Indeed, splendid work once again.

Talking about design, I have some issues with the bowsting grider. The supporting cylinder looks odd. It is like this, because on one hand the girders are holding the construction on the sides, while the cylinder supports only the center part. Central cylinder support columns are fine for concrete counstructions, but rather not here.
I have never seen Barnes Bridge IRL, so I googled some pics and they confirmed what I was thinking... A rounded cuboid would look much more better or maybe two or three cylinders in one line could also do the job.

I might add some costs and appearence comments later if you wish so.
Title: Re: Bridges
Post by: The Hood on January 05, 2012, 09:05:10 PM
@ARkadiusz, I think you're right about the bowstring girder.  The screenshot below shows it using a brick base pillar instead.  What do you think?

@sdog - the colour of the iron arch is player colour, set to brown in the example above.  Green shown below.  Iron lattice bridges like that are quite common in the UK, especially in our cities for railway viaducts built in the 1800s.  The bridge is loosely based on Fulham railway bridge, which has the struts as decoration.  Not sure what you meant for the rest of your comment re height restrictions either...

(http://img851.imageshack.us/img851/3135/bridges.jpg) (http://imageshack.us/photo/my-images/851/bridges.jpg/)
Title: Re: Bridges
Post by: jamespetts on January 05, 2012, 09:36:16 PM
I wonder whether the bowstring bridge is a little high? I appreciate the problem with the repeating tiles (or else it'd be the same height with a longer top part), but, perhaps, to compensate, one can make it lower, so that it does not look vertically stretched?
Title: Re: Bridges
Post by: AP on January 05, 2012, 11:07:38 PM
The wrought iron arch bridge is very nice indeed. Hope the speed limit's sufficiently high that we can have an excuse not to replace it too soon in-game!
Title: Re: Bridges
Post by: Fabio on January 06, 2012, 12:06:29 AM
Hey folks, do you mind if I steal some of your bridges and adapt them to pak 128? I would obviously credit The Hood in copyright strings...
Title: Re: Bridges
Post by: The Hood on January 07, 2012, 01:32:14 PM
Fabio, that's absolutely fine.  Which format suits you best? I have .blend, .xcf and .png (the last of which, as always, is available in SVN for the graphics I have already uploaded and others will appear soon). Perhaps I could trade you for some citybuildings - did you get anywhere with the pak128.Britain textured versions of your blocks?
Title: Re: Bridges
Post by: AP on January 07, 2012, 02:21:27 PM
Just thought I should report a few in-game oddities with the new railway bridges:

Tubular box girder bridge - intermediate piers. The piers for this type don't occur between every tile, which looks good when the game draws them 'correctly', but that doesn't seem to be all the time. They often seem to occur asymmetrically and off-centre. e.g I'd expect to see pier spacings of 2-2-2 (tiles) or 1-2-2-1 or 1-3-1 but I often get more like 1-4 which looks a bit odd (though granted not impossible).

The Tubular Box Girder bridge and Steel Beam bridge prices are presumably placeholders - construction 0.01c and maintenance 0.04c is rather favourable!

Lastly, some of the bridges seem to have length limits associated with them again - I recall this being disucssed previously and removed e.g from the brick viaducts. Not sure if it was deliberate they've been included?

Edited: typo.
Title: Re: Bridges
Post by: The Hood on January 07, 2012, 03:07:52 PM
Pier spacing is done by placing a pier every x tiles, 4 in the case of the tubular box girder, counting from one end. It knows notginf of symmetry. It may be improved by lower spacings but that is the price you must pay.

Re lengths, we need a way of differentiating between the different types with costs, height and length limits. Some types will be limited, others won't.
Title: Re: Bridges
Post by: ӔO on January 08, 2012, 10:50:23 AM
I guess it would be possible to make a grid chart for the cost vs. length of each type of bridge.
looking at the various wiki pages (although this means take with grain of salt) and some other stuff I've read in the past.

There are a lot of variations with each type of bridge, so these are just general figures.
Bridge Type Maximum spanStrengthMaterial efficiencyDesign effort
(between pillars)
Rolled steel girder30mLight to Med.PoorLow
Plate girder100mLight to Hvy.PoorLow
Concrete girder50mMed. to Hvy.Poor to FairMedium
Steel box girder100m?Light to Hvy.Poor to FairHigh
Concrete box girder100m?Med. to Hvy.FairHigh
Tubular Box girder140m?Med. to Hvy.Poor to FairHigh
Masonry arch140m+Med. to Hvy.Poor to FairLow to Med
Steel arch550mMed. to Hvy.FairMed. to High
Concrete/Steel arch330m?Med. to Hvy.FairMed. to High
Truss26m?Light to Hvy.HighMedium
Pratt Truss76m?Med. to Hvy.HighMedium
Continuous truss400mMed. to Hvy.FairMedium
Truss Cantilever549mMed. to Hvy.Fair to HighMedium
Concrete Cantilever100m+Med. to Hvy.Fair to HighMed. to High
Cable Stayed1088mMediumHighHigh
Suspension1991mMedium HighHigh
Design Effort, I would guess, is how much planning and work must be necessary to construct the bridge. Longer spans, total and between the pillars, obviously require more effort.

The box and plate girders are what the modern elevated ways are made from.
Title: Re: Bridges
Post by: The Hood on January 08, 2012, 01:59:23 PM
Helpful, AEO. What we need to do is translate this from engineering terms to simutrans variables, namely speed, weight limit (?), length limit, height limit, capital cost and maintenance cost.

I suppose there is the issue of total length of bridge vs total distance between pillars.  Clearly a brick arch viaduct has a short span, but can be very long in total and I intend this to remain unlimited in the pak.  Is it worth having total length limits at all? Height limits I will include, because some bridge types have pillars which do not exceed certain heights.

Strength - this can be related to weight limits.  Am I right in thinking standard now incorporates something along these lines? If so, how?

Material efficiency/Design effort - can these easily be related to capital cost and maintenance cost?
Title: Re: Bridges
Post by: jamespetts on January 08, 2012, 02:08:23 PM
It is, in my view, worth having total length limits, since some bridges don't have supports. In Experimental, I have differentiated between bridges that can and cannot have supports, and made those that cannot have supports less expensive, but have shorter spans. I intend to integrate your lovely new bridge graphics into the next Experimental release, and try to harmonise the way in which the bridges have been set up in Standard, but there might be some useful parameters in the Experimental bridges (largely sharing graphics at present) which might be helpful to implement: see here (https://github.com/jamespetts/simutrans-pak128.britain/tree/master/ways) for the bridges.
Title: Re: Bridges
Post by: ӔO on January 08, 2012, 02:53:33 PM
@Hood
I would guess a high design effort would cause an increase in initial cost, because an expert engineer must be hired.

Material efficiency is pretty easy. More efficient will mean cheaper to build for any given length.
Strength can determine maximum speed and weight. It's usually lighter and faster or heavier load and slower. For the purpose of standard, "medium" would be something like 110km/h for road vehicles. Mostly all rail bridges would fall under heavy. I probably should have made a "Very Heavy" for high speed rail
Title: Re: Bridges
Post by: AP on January 08, 2012, 03:27:49 PM
It is, in my view, worth having total length limits, since some bridges don't have supports.

Which types don't have supports? And do you mean don't have them in-game just because they haven't been drawn? I ask because, in reality, I don't think any type has a length limit on potential design, if you can provide intermediate piers.

I think the focus on capital cost, maintainance cost, and weight / speed limits, is the way to go.
Title: Re: Bridges
Post by: jamespetts on January 08, 2012, 03:38:34 PM
Ahh, I think that the position is more subtle than that: the basic types of bridge are indeed capable of having supports, but supports cost money. In Simutrans, the bridge cost is a fixed per tile value, without taking into account whether there are supports or not. In order to have realistic costings, one needs a bridge without supports to have a fixed maximum length, and the supported version to cost more, but have no such maximum.
Title: Re: Bridges
Post by: Arkadiusz on January 08, 2012, 04:35:22 PM
@The Hood

This now looks a lot better :) Though, I still feel there is something to be improved on the bowstring girder. The base on which rail tracks are laid suggests to be thick and solid looking on the top of it (as it is the same texture as for rail tracks on ground), yet it is very thin from the side perspective. Maybe it would look better after changing the texture on the top to something that is partially transparent... as many such bridges do not use any stone underlay and tracks are put straight on the skeleton structure of the bridge.
Title: Re: Bridges
Post by: The Hood on January 08, 2012, 05:43:21 PM
@jamespetts,

Shorter spans still need the abutments, which would cost a fixed amount regardless of the span.  So for longer bridges of the same type, the additional support cost would be comparable (logically at least, no idea about numbers in real life!) to abutments. So I'd say it's probably OK to have a single cost per unit length, and avoid having too many bridges to choose between in the menu. Certainly in standard I will be having just a single type and I'm erring more and more towards no length limits.

@Arakdiusz,

how about this? This is just using the same deck used in the steel truss bridge, but everything else is the same.

(http://img40.imageshack.us/img40/1083/bridge2o.jpg) (http://imageshack.us/photo/my-images/40/bridge2o.jpg/)
Title: Re: Bridges
Post by: Arkadiusz on January 08, 2012, 06:53:38 PM
Yeah, that made the difference. Thumbs up.
Title: Re: Bridges
Post by: The Hood on January 08, 2012, 07:21:36 PM
Back to drawing now: iron lattice bridge...

(http://img861.imageshack.us/img861/5897/ironlatticeviaduct.jpg) (http://imageshack.us/photo/my-images/861/ironlatticeviaduct.jpg/)
Title: Re: Bridges
Post by: jamespetts on January 08, 2012, 07:37:18 PM
I really like that one!
Title: Re: Bridges
Post by: wlindley on January 08, 2012, 10:01:33 PM
Thread should be subtitled: Isambard Kingdom Brunel...!
Title: Re: Bridges
Post by: The Hood on January 08, 2012, 10:41:37 PM
Thanks.  Finally (for today) the cornish-style wooden viaduct with stone pillars - a work in progress as I'm not happy with the pillar textures yet, but a preview nonetheless:

(http://img828.imageshack.us/img828/3851/cornishviaduct.jpg) (http://imageshack.us/photo/my-images/828/cornishviaduct.jpg/)
Title: Re: Bridges
Post by: jamespetts on January 09, 2012, 02:35:43 AM
These are extremely impressive!
Title: Re: Bridges
Post by: ӔO on January 09, 2012, 04:03:29 AM
I think that newer railroad deck is excellent for the truss type bridges.

I've found these documents that describes costs and maintenance of bridges.
http://www.iti.northwestern.edu/publications/utc/tea-21/FR-4-6-Krizek.pdf (http://www.iti.northwestern.edu/publications/utc/tea-21/FR-4-6-Krizek.pdf)
http://www.esc.vic.gov.au/NR/rdonlyres/98A7F47C-5ABC-4691-AB18-38FD41D073CE/0/MaintenanceCostBenchmarkingFinal.pdf (http://www.esc.vic.gov.au/NR/rdonlyres/98A7F47C-5ABC-4691-AB18-38FD41D073CE/0/MaintenanceCostBenchmarkingFinal.pdf)

A more mathematical approach to calculating maintenance cost.
http://users.encs.concordia.ca/~hammad/papers/C13.pdf (http://users.encs.concordia.ca/%7Ehammad/papers/C13.pdf)
Title: Re: Bridges
Post by: AP on January 09, 2012, 10:46:52 AM
These are really good Hood! Would a lighter timber colour on the cornish style viaduct perhaps allow the shape of the fan to show more clearly? (ie greater difference between highlight and shadow) Just a thought.
Title: Re: Bridges
Post by: jamespetts on January 09, 2012, 08:45:34 PM
Of note to this topic, have a look at this (https://github.com/aburch/simutrans/commit/f730a13c83f59417be265cd9635cc218fc7c50b2) very recent commit Standard, which permits elevated ways to be used over shallow water (with a depth equal to 1). This possibility may wish to be considered when implementing bridges.

Edit: One thought has occurred to me on the utility of maximum length restrictions, which had not occurred to me before: if I understand correctly, the view so far taken, I think, has been that there is no need to have different types of bridges with and without pillars, since pillars are simply added automatically where and if they are needed, and, since a bridge with pillars is usually theoretically unlimited in length, there is no need to have a length limitation for any bridge.

The difficulty that has just occurred to me with that is this: there is also a maximum height parameter. Bridges with no pillars, obviously, have an unlimited height (as it matters not one whit to the structural integrity of the bridge how far the drop is provided that it is secured effectively on its banks). Conversely, bridges with pillars, while having a theoretically unlimited length, have a limited height. So, pillarless bridges have a height limitation, and pillarful bridges have a length limitation. Putting the two together is not the same as having a bridge with neither limit, since a particular type of bridge might need to be too long to be built pillarless, but over too high a gap to be built with pillars, making the gap uncrossable without using a different type of bridge.

See also here (http://forum.simutrans.com/index.php?topic=8937.new#new) for my extension request in relation to bridge heights.
Title: Re: Bridges
Post by: The Hood on January 09, 2012, 10:11:36 PM
Hmm, I get your point but the thing is that in Simutrans you can only change elevation by 1 per tile, so in order to have a truly deep gap to cross it must also be quite long (e.g. 8 tiles or more). Longer, in my opinion, than any pillarless bridge to look good in the game. I'm still to be convinced that single span bridges without pillars, with a length limit and no height limit have any role to play either, given what length they would need to be for the lack of height limit to be important. I'm generally for giving a good range of bridges visually, with some differentiation along cost height and speed lines.
Title: Re: Bridges
Post by: prissi on January 09, 2012, 10:33:23 PM
You can change height by two tiles with the slope tool though.
Title: Re: Bridges
Post by: AP on January 09, 2012, 11:24:05 PM
Quote
You can change height by two tiles with the slope tool though.
I tried in-game, yes, it's possible, but quite tricky to gain height at a faster rate than 1:1, and certainly the game doesn't seem to generate terrain steeper than that.

Quote
there is also a maximum height parameter
So I've just discovered - none of the bridges in game will build over a nice 32-wide by 16-deep gorge I created as a test. Can i suggest the bridge types should tell us these h and l limits in the menus, to aid choice?

Title: Re: Bridges
Post by: The Hood on January 10, 2012, 06:11:12 PM
There is an absolute limit imposed on all bridges of +7 height. This can be reduced for individual types.
Title: Re: Bridges
Post by: ӔO on January 10, 2012, 07:16:01 PM
From my testing, the maximum height is 8 and the shortest span possible with that height difference is 9 tiles.
which makes me wonder if a dat specified max height is necessary at all.
Title: Re: Bridges
Post by: jamespetts on January 10, 2012, 11:35:49 PM
That is interesting. Would it be possible to give a chart of minimum length per tiles of height to enable the issue to be considered more fully?
Title: Re: Bridges
Post by: sdog on January 11, 2012, 03:40:19 AM
with elevated ways being buildable on water now, is it even necessary to keep the viaducts as bridges?


modification: to answer my own question: elevated ways can be only one level high. another level would require the player to stack them, quite awkward.


This is also a real construction option, with a bridge between two sections of elevated way, and artificial slopes, one can easily build a one square wide three level deep drop to bridge.
Title: Re: Bridges
Post by: prissi on January 11, 2012, 07:38:20 AM
You need a bridge to connect to an elevated way ... but you can keep it of course to single tile length.
Title: Re: Bridges
Post by: sdog on January 11, 2012, 08:09:41 AM
Ah, yes. I just realized that what i had in mind is not possible at all at this time.

A bridge can be connected to an elevated way only at one end. It can not be used between two pieces of elevated way.
If one needs a bridge

example (E=elevated way, B=bridge, _ = any ground)

___EEE
this works
__BEEE

EEE__EEE
here it doesn't
EEEBBEEE

btw, it is possible to attach elevated ways directly to artificial slopes.  That's also whats used to build diagonal "bridges" (workaround).
Title: Re: Bridges
Post by: ӔO on January 11, 2012, 09:25:12 AM
That is interesting. Would it be possible to give a chart of minimum length per tiles of height to enable the issue to be considered more fully?
if each step is allowed to have a 2 tile height difference, then these would be the numbers.
H= height
L= length end to end.

H:8, L:9
H:6, L:7
H:4, L:5
H:2, L:3
Title: Re: Bridges
Post by: wlindley on January 11, 2012, 03:27:22 PM
Loving the new bridges, but could we go back to the issue of building cost and operating cost?  All the costs seem much too low.

For example, Phoenix Arizona in 2008 opened its new tram system; the cost for the entire 20-mile line, 50 trams, and a full modern maintenance facility was $1,200,000,000. The cost of one mile of line laid in the street was about $20,000,000. The single main-line 500 metre bridge over the Salt River in Tempe, however, cost $300,000,000. 

In general, bridges have cost about 10 times at-grade rail.  A good range would be from 5 times to 20 times depending on bridge type.

As far as game play -- bridges are some of the most spectacular parts of our railroads, and deserve the best planning.  A higher initial cost would reflect this.
Title: Re: Bridges
Post by: jamespetts on January 11, 2012, 10:37:14 PM
WLindley,

I am very interested in real world pricing information for balancing purposes; is your "in general" figure based just on the two examples that you gave, or is it based on anything else? And has that ratio remained largely constant throughout history, or was it different, say, 100 or 150 years ago?
Title: Re: Bridges
Post by: ӔO on January 11, 2012, 10:50:13 PM
I know I've read a report before on how bridge prices always end up being about 30% higher compared to initial estimates 60% of the time.
it might have been on a news piece about the costs of the new oakland bay bridge in san fransico.
Title: Re: Bridges
Post by: wlindley on January 12, 2012, 12:36:19 AM
I found a reference of page 53 of the Google scan of the 1832 American Rail-Road Journal (http://books.google.com/books?id=CBY7AAAAMAAJ&pg=PA372&lpg=PA372&dq=railroad+%22cost+per+mile%22+bridge&source=bl&ots=UmO6qClpZd&sig=UTGcBhbr8M07u12GhbxpniNOEZc&hl=en&sa=X&ei=ryEOT-amMsX5rAfMm9T5AQ&ved=0CLEBEOgBMBM#v=onepage&q=railroad%20%22cost%20per%20mile%22%20bridge&f=true) for construction costs on the Fifth Division Baltimore & Ohio Railway.

This division had 11 miles of grade, and "three bridges of one arch each, and of the following chords, to wit, 30, 20, and 10 feet respectively; and one viaduct of the Rail-road for the Georgetown and Frederick turnpike road, of stone abutments and superstructure of wood of 24 foot span. This viaduct is elevated [16 feet 1.2 inches] above the gradated surface of the Rail-road."

The 11 miles of gradation cost $66,614 (about $6,000 per mile) while the masonry for division altogether cost $12,068 (for 84 feet (!) in four bridges plus an unspecified number of smaller culverts). 

Altogether my feeling is that this example suggests a Simutrans tile of masonry bridge should cost about 20 times a standard tile. 

This document for Washington State's Sound Transit (http://art-collecting.com/tacoma/Design-Cost-Analysis-Report.pdf) lists a cost of $10,140 per foot for a long post-and-beam bridge, while this document from the State of Michigan (http://www.michigan.gov/documents/Vol2-40UIP16SubDevCosts-YardCosts-Demolition_121083_7.pdf) lists an installed cost for railroad sidings (spurs) to be about $170 per foot (for 115-pound rail with 9-foot concrete roadbed)... the bridge costing sixty times a simple siding. However a siding costs less than a main-line track... again, 20 times seems about the right answer.

p.s., That 1832 article has a variety of figures quoted for European railways as well, unfortunately the scan process has obscured too many of them.
Title: Re: Bridges
Post by: jamespetts on January 12, 2012, 01:46:43 AM
Very interesting, thank you!
Title: Re: Bridges
Post by: AP on January 20, 2012, 10:30:45 PM
If the cost of bridges is being seriously reviewed, it might be worthwhile to revisit the discussion about the cost of altering terrain (link (http://forum.simutrans.com/index.php?topic=2836.msg28603#msg28603)), to ensure the desired incentives and balances are maintained.
Title: Re: Bridges
Post by: The Hood on January 21, 2012, 10:30:08 AM
So where does this leave us in terms of costs for bridges and altering terrain? Looking at rail only for the time being:

Track Costs (maintenance in brackets):
wrought iron: 30.00 (3.00) for 60km/h
improved wrought iron: 150.00 (16.00) for 110km/h
WSSR: 250.00 (26.00) for 145km/h
WSSRI: 400.00 (36.00) for 175km/h
CSSR: 500.00 (44.00) for 200km/h
CSSRI: 600.00 (48.00) for 225km/h
High Speed: 1,000.00 (72.00) for 320km/h

1) are these costs acceptable (a) relative to one another and (b) as an absolute reference point for the game?

Land costs:
alter land: 1250.00 (0.00)
artificial slopes: 1500.00 (0.00)

2) Already discussed in linked thread, but (a) what balance should these have relative to one another and (b) what should they cost relative to tracks?

Bridge costs:
Wooden trestle: 250.00 (7.00) for 30km/h
Brick Viaduct: 1,900.00 (72.00) for 160km/h

Elevated ways:
Brick Arch elevated way: 250.00 (26.00) for 145km/h

3) what costs should bridges have relative to altering terrain and altering tracks (NB these are not independent: fixed by whatever gets decided about terraforming and track costs)?

Other points to note:
- Partially the problems are one of scale. Taking the "official" scale of 1 tile = 1kmx1km (which I've never liked even remotely because of the graphical absurdity of it all) then steep embankments/cuttings are the way to go - the tapering is irrelevent on that scale. The graphical scale however is that 1 tile is approx 30-100m (depending on context), which probably makes embankments/cuttings with a slope slightly more realistic, but wouldn't entirely rule out the sheer drop type.
- If "sheer drop" is considered as in the suggestion in the other thread, i.e. make it very expensive as it's unrealistic, then what about elevated ways? These can only be built one high, but are effectively a "sheer drop" plus track and plus maintenance. Why ever bother with these except where requiring to cross another way? Is that the right way to go? Should they be cheaper or more expensive than sheer drop terraforming?


Title: Re: Bridges
Post by: AP on January 21, 2012, 11:00:31 AM
My position is that the pricing structure and balancing should encourage a creative mix of all the options to be used by the player, to maximise price advantage, and thereby appear realistic.

As such, building on that earlier work, I think the balance needs to be:

( 2x cost_alter_land )  < all bridge prices (possibly except slow timber bridge) < cost_set_slope < elevated way

  • 2x cost_alter_land is the cost of raising one tile (assuming infinitely long embankment)
  • I assume bridges would be priced in a spectrum, like track, to represent their speed restrictions etc?
  • Elevated ways have two quite distinct advantages over embankments, as I see it, hence are very useful:
  • Flexibility - unlike bridges they can be built diagonally, and can have intermediate junctions.
  • Impact - unlike sheer embankments, they preserve buildings and other urban infrastructure underneath,  (and preserves passenger-generating buildings). This results in a very considerable saving on urban demolition (which can easily exceed $10000/tile) compared to a sheer embankment. As such I think the per-tile pricing for elevated ways should be greater than the price for cost_set_slope. It could take into account the cost of a typical urban building (obviously not the very expensive ones which are to tall to bridge over). Possibly maintenance of elevated ways should still match the brick viaduct though.
Quote
altering terrain and altering tracks (NB these are not independent: fixed by whatever gets decided about terraforming and track costs)?
Can you clarify this? - which variable is controlling the cost for track demolition/changes then? Because track changes at present are far cheaper than any terrain alterations...

Edit - add the bullet for 2x cost_alter_land
Title: Re: Bridges
Post by: The Hood on January 21, 2012, 11:05:06 AM
Can you clarify this? - which variable is controlling the cost for track demolition/changes then? Because track changes at present are far cheaper than any terrain alterations...

I meant that if you decide what the ratio of costs track:terraforming is and track:bridges you automatically define bridges:terraforming.
Title: Re: Bridges
Post by: AP on January 21, 2012, 11:09:16 AM
Ah, I see, quite true! I'm not sure track:terraforming is as important as the other two in terms of influencing player choice of route/costruction, i'd let that be the one to be defined 'automatically'.
Title: Re: Bridges
Post by: The Hood on January 21, 2012, 05:00:02 PM
More thoughts:
- I don't want to set the maintenance of bridges punishingly high, especially if they are to cost e.g 20x normal track. How about double the cost of track of a similar speed?
- elevated ways shouldn't cost more than bridges per tile - they are effectively bridges that can go round corners
- why should bridges be cheaper than retaining walls and earth that we are envisaging for artificial slopes? After all they have disadvantages that AP has suggested e.g. demolishing buildings in their way, and don't include track either...

Anyway, keeping the cost of rails fixed for now, and merging in the ideas so far, I suggest the following for comment:

Brick Viaduct/Elevated way: 6,000.00 (72.00) for 160km/h, unlimited length and height
Wooden trestle: kept as is at 250.00 (7.00) for 30km/h given the very low speed limit. Unlimited length but height limited to +3 or 4?
Proposals for new bridges:
Brick Viaduct 115: 5,000.00 (50.00) for 115km/h, unlimited length and height limited to +5
Masonry Viaduct (not drawn yet): 3,500.00 (30.00) for 70-80km/h. Unlimited length but height limited to +4 (mid weight limit)
Wooden trestle stone viaduct: 3,000.00 (40.00) for 70km/h Unlimited length and height (low weight limit)
Wrought Iron lattice viaduct: 3,500.00 (80.00) for 130km/h Unlimited length and height
Wrought Iron lattice girder: 5,000 (60.00) for 145km/h max height +2
Tubular box girder: 4,000 (50.00) for 120km/h max height +5
Steel beam: 3,500.00 (50.00) for 120km/h max height +3 moderate weight limit max length 10
Steel Truss: 6,500.00 (90.00) for 175 km/h - max height +2 (mod-high weight limit) max length 10
Wrought Iron Arch: 5,500.00 (60.00) for 145km/h max height +3
Wrought Iron Bowstring girder: 5,000.00 (55.00) for 145km/h max height +2
Steel/Concrete Bowstring girder (not drawn yet): 6,000.00 (64.00) for 160km/h max height +3
Plate Girder Brick: 5,000.00 (50.00) for 145 km/h - max height +1 max length 4
Plate Girder Concrete: 8,000 (72.00) for 175km/h - max height +1 max length 4
Concrete Viaduct: 10,000.00 (80.00) for 175 km/h no limits
Concrete Viaduct: 12,000.00 (100.00) for 225 km/h no limits
Concrete Viaduct: 20,000.00 (150.00) for 320km/h no limits

Alter slope tool: 1,000.00 (0.00) (this will rack up though with extra height...)
Artificial slope tool: 2,000.00 (0.00)

Thoughts?

Title: Re: Bridges
Post by: AP on January 21, 2012, 05:57:47 PM
Quote
I don't want to set the maintenance of bridges punishingly high, especially if they are to cost e.g 20x normal track. How about double the cost of track of a similar speed?
I agree. Maybe a little low, but perhaps best reviewed in play-testing.

 
- why should bridges be cheaper than retaining walls and earth that we are envisaging for artificial slopes? After all they have disadvantages that AP has suggested e.g. demolishing buildings in their way, and don't include track either...
Hmm.  They shouldn't be cheaper than 'simple' earthworks, but should be preferred over 'complex' ones. The trouble is the limited number of variables. At what point bridges are preferred over earthworks is, I think, the more complex question.

Quote
Alter slope tool [cost_alter_land]: 1,000.00 (0.00) (this will rack up though with extra height...)
Artificial slope tool [cost_set_slope]: 2,000.00 (0.00

 In that scenario, across open fields, a +1 sheer embankment costs the same as a sloped embankment. And also it's almost always cheaper to build a +2 sheer embankment (2000/tile) than a bridge, though the former look really crude in game (not an insignificant consideration) and have 0 maintenance excl track, whereas a +2 sloped embankment (more attractive) costs 6000/tile when it ought to be cheaper.

If a sheer embankment is equally cheap as a sloped embankment, nobody will build the sloped embankments even when they have the space, so the sheer one has to be at-least-slightly pricier.
To rectify that for +1 needs cost_set_slope > 2x cost_alter_land
To rectify that for +1 and +2 needs cost_set_slope > 6x cost_alter_land (if I got my maths right...)





Title: Re: Bridges
Post by: jamespetts on January 21, 2012, 06:09:41 PM
Do we not need to look into the historical costs of bridge maintenance?
Title: Re: Bridges
Post by: The Hood on January 21, 2012, 06:10:18 PM
So if I understand you correctly, we could set artificial slopes at 6,000. This would make them as expensive as bridges for forming embankments, but would have an application in situations where you needed to create a ledge to fit the track along without demolishing an entire mountain. Probably about right.

Regarding historical costs of bridge maintenance, be my guest in experimental, but as a starting point I would just get something that allows each bridge type to have a niche in game, especially in standard where the number of parameters to play with are reduced. Don't forget there's no inflation, and no increase in maintenance with age. Keep it simple...
Title: Re: Bridges
Post by: AP on January 21, 2012, 06:25:34 PM
Quote
We could set artificial slopes at 6,000
Yes, that would seem a good value to use initially. Higher would have advantages as stated previously, but possibly also disadvantages.

Quote
Regarding historical costs of bridge maintenance, be my guest in experimental, but as a starting point I would just get something that allows each bridge type to have a niche in game, especially in standard where the number of parameters to play with are reduced. Don't forget there's no inflation, and no increase in maintenance with age. Keep it simple...

I agree I think - since the graphics now exist and are going into the game, best to get the values/parameters roughly balanced, then maybe review later if better information becomes available.
Title: Re: Bridges
Post by: wlindley on January 21, 2012, 07:09:17 PM
To keep things simple:
  • Purchase cost should increase (slightly exponentially) less than the square of maximum weight load (which is a game factor in Experimental) and maximum length (for bridges where length is a factor).
  • Maintenance cost should increase (slightly exponentially) less than the square of maximum speed
In each era a small variety of bridges should be available:
  • slow, light: cheap to build and maintain.
  • slow, heavy capacity: moderate to build, cheap to maintain
  • fast, medium capacity: fairly cheap to build, fairly expensive to maintain
  • fast, heavy capacity: fairly expensive to build, fairly expensive to maintain
The goal here is to force the player to make decisions, highlighting each player's and each terrain's unique economics and demand in engineering techniques.
Title: Re: Bridges
Post by: AP on January 21, 2012, 07:13:50 PM
Sounds good.

Quote
The goal here is to force the player to make decisions, highlighting each player's and each terrain's unique economics and demand in engineering techniques.
I agree entirely.
Title: Re: Bridges
Post by: The Hood on January 21, 2012, 07:16:53 PM
Would either of you like to make any suggestions as to which bridges fit which and put some numbers to them? That would help me massively...
Title: Re: Bridges
Post by: Spike on January 21, 2012, 09:52:23 PM
Altogether my feeling is that this example suggests a Simutrans tile of masonry bridge should cost about 20 times a standard tile. 

Thank you, this is a very useful rule of thumb!
Title: Re: Bridges
Post by: wlindley on January 21, 2012, 10:18:08 PM
I have assembled a spreadsheet here (http://wlindley.com/images/simutrans/bridges-new.xls) where the second page is based on data from the Experimental .dat files, and a set of linear and logarithmic factors.  The model is calibrated so the early wooden and brick bridges approximate their current costs.  The later faster and higher-capacity bridges are generally more expensive than currently, although note: The Concrete Spanning Bridge (Light) would now cost half as much to build while maintenance costs would double; meanwhile the Heavy version would cost more than twice as much to build, and maintenance costs would also more than double.  Available during the same era, however, are several bridges like the Steel Box Girder which are a significant savings in both building cost and maintenance, if slightly lower capacities and speeds are not an issue.

Feel free to adjust the factors at the top of the page.
Title: Re: Bridges
Post by: jamespetts on January 22, 2012, 12:20:47 AM
Thank you - that looks very useful! I shall have to look into that in more detail when I get the time.
Title: Re: Bridges
Post by: The Hood on January 22, 2012, 06:02:29 PM
Wlindley

A few qustions about this:
1) does this incorporate the 20x standard tile rule of thumb? Prices generally seem quite low compared to what I worked out above, and seem a bit low compared to the raising land option discussed above.
2) This is for experimental, which for historical reasons has separate bridge types (and I don't think jamespetts is planning on changing them to the types I have drawn which will be the ones in standard). How hard would it be for you to do a similar job for standard?
Title: Re: Bridges
Post by: jamespetts on January 22, 2012, 06:17:26 PM
I have yet to decide exactly how to integrate the latest Standard bridges into Experimental, but, whatever I do, I shall certainly be making use one way or another of all of The Hood's excellent bridge graphics.
Title: Re: Bridges
Post by: wlindley on January 23, 2012, 12:42:42 PM
Ah, I used Experimental's data files because they had the weight limits.  Here (http://wlindley.com/images/simutrans/bridges-new2.xls) is a revised spreadsheet, with eight pages (four for Standard, four for Experimental), (track, bridge, construction, and maintenance costs for each).  The Standard base sheets do some weight lookups into the data from Experimental. 

I hope you find the construction and maintenance costs here to have sensible ratios to the costs for similar at-grade track.  If not, adjust the parameters in the yellow shaded boxes.  Each Cost and Maintenance line has a Subjective entry field as well, in which I have placed some "fudge values" to make the very early and very late bridges seem right.

For Standard, a difficulty arises in that the two Brick viaducts, which are available quite early, have much higher speed limits than will be possible for years after their introduction, which skews the costs.  Perhaps a slightly wider variety across the years would be appropriate.
Title: Re: Bridges
Post by: The Hood on January 28, 2012, 04:42:19 PM
OK,  I've now added the bridges (along with a couple of extra ones) and rebalanced the costs. Do let me know how these costs work for you.
Title: Re: Bridges
Post by: wlindley on January 28, 2012, 06:56:27 PM
Very nice!  And the additions are simply grand. This is a nice variety, with a little emphasis on economic as well as aesthetic influence on the game. I quite like the wooden trestles with stone pillars, and the iron lattice.

 Should I do the same spreadsheets for roads now? =grin=
Title: Re: Bridges
Post by: The Hood on January 29, 2012, 09:55:25 AM
If you want to...
Title: Re: Bridges
Post by: wlindley on January 30, 2012, 01:46:11 AM
Standard and Experimental road bridges, with possible construction and maintenance costs, here (http://wlindley.com/images/simutrans/road-bridges.xls).  As before, the yellow squares are for input coefficients. 

For Standard, the early bridges are just about right although MasonryViaductCobbles probably should have its construction cost increased.  The concrete bridges all should have their cost increased by five or six times... other than that, things are fairly sensible as-is.

Experimental's curves are much sharper, and it seems the bridges need much more adjusting.
Title: Re: Bridges
Post by: AP on January 31, 2012, 02:28:21 PM
So I was playing recently with the elevated ways. Irritated at a big valley which needed crossing on the skew, I stacked up the diagonal elevated ways pont-du-gard style, resulting in a nice 5-high diagonal viaduct, very functional but a bit ugly. I then discovered that you can demolish the lower tiers, leaving just the upper tier looking more 'normal', albeit floating on air.

So I now wonder, is there any way we could have the bridge piers buildable in-game?. Probably at low cost, to allow us to tidy up such construction visually? Curved viaducts look really good in-game and are rather useful.

Title: Re: Bridges
Post by: ӔO on January 31, 2012, 03:00:39 PM
So I was playing recently with the elevated ways. Irritated at a big valley which needed crossing on the skew, I stacked up the diagonal elevated ways pont-du-gard style, resulting in a nice 5-high diagonal viaduct, very functional but a bit ugly. I then discovered that you can demolish the lower tiers, leaving just the upper tier looking more 'normal', albeit floating on air.

So I now wonder, is there any way we could have the bridge piers buildable in-game?. Probably at low cost, to allow us to tidy up such construction visually? Curved viaducts look really good in-game and are rather useful.


on the japanese simutrans site,( http://japanese.simutrans.com/index.php?Addon128%2FRoadTools%201 (http://japanese.simutrans.com/index.php?Addon128%2FRoadTools%201) ) there is a set of elevated roads with just the pillars, which is for stacking.
it should be possible to do that with the elevated ways I drew, since the pillars are full height.
Title: Re: Bridges
Post by: The Hood on February 03, 2012, 10:05:58 PM
Sounds like a good idea - minimal cost and maintenance and 0 speed to prevent trains running on them.
Title: Re: Bridges
Post by: Fabio on March 24, 2012, 12:03:44 AM
Here's a very interesting reading about bridge types. I wanted to share it, although many of these types are not possible / not nice with the current bridges code.

http://pghbridges.com/basics.htm
Title: Re: Bridges
Post by: AP on March 24, 2012, 01:53:45 PM
Nice page, there are so many different trusses it's astonishing (they forgot the very useful Vierendeel truss, for instance.
Title: Re: Bridges
Post by: The Hood on April 02, 2012, 07:58:28 PM
Bridge costs are now updated in SVN to more closely match the rail bridge costs. Do comment as necessary...
Title: Re: Bridges
Post by: AP on April 02, 2012, 09:29:21 PM
Sounds like a good idea - minimal cost and maintenance and 0 speed to prevent trains running on them.
Yes, that sounds excellent.
Title: Re: Bridges
Post by: ӔO on April 02, 2012, 10:00:45 PM
for the april 2nd nightly build
balance seems to be okay.

just 3 things I've noticed
steel truss railway bridge, "pillar_asymmetric=1" might be missing. Right now, the pillars from one side are too long.
iron lattice girder rail bridge, might be better with "pillar_distance=1" instead of 2.
concrete railway viaduct 225 might be in there twice.

otherwise, excellent work
Title: Re: Bridges
Post by: jamespetts on April 29, 2012, 02:30:05 PM
I am just beginning the process of integrating all of these into Experimental, and I have noticed that we appear to be missing the concrete elevated way, which is quite important in modern cities. Are there any plans to add this?
Title: Re: Bridges
Post by: The Hood on April 29, 2012, 04:34:57 PM
Yes - I haven't done any more elevated ways yet - just bridges (see the to-do list)
Title: Re: Bridges
Post by: The Hood on January 05, 2013, 10:22:08 PM
Time for some elevated ways. First up, an elevated way version of the wooden trestle rail bridge. I also took the opportunity to do better snow graphics for all wooden trestle rail bridges as shown in the second image:

(http://imageshack.us/a/img248/2633/trestleelevated.jpg)

(http://imageshack.us/a/img827/3361/trestlesnow.jpg)
Title: Re: Bridges
Post by: jamespetts on January 05, 2013, 10:24:54 PM
Delightful!
Title: Re: Bridges
Post by: AP on January 05, 2013, 11:18:05 PM
(http://imageshack.us/a/img827/3361/trestlesnow.jpg)
Love this image!  ;D

(wish we could get the piers to taper though...)

Edit: 3rd pier (counting from Left) - base seems too low. Graphical glitch? 2nd and 3rd pier should be the same length, no?
Title: Re: Bridges
Post by: greenling on January 06, 2013, 11:33:38 AM
Very Cool.
Title: Re: Bridges
Post by: ӔO on January 06, 2013, 11:35:34 AM
Love this image!  ;D

(wish we could get the piers to taper though...)

Edit: 3rd pier (counting from Left) - base seems too low. Graphical glitch? 2nd and 3rd pier should be the same length, no?

probably needs a line

I think it was pillar_asymmetrical=1
Title: Re: Bridges
Post by: The Hood on January 06, 2013, 10:00:18 PM
@AEO - it already has that line. There are a few glitches in the bridge code I think. It's not the only bridge where you can see this, especially after rotation.

Anyway, here's some concrete rail elevated ways. The keen-eyed among you will spot two subtly different types with different speeds...

(http://img266.imageshack.us/img266/9261/concreteelevatedway.jpg) (http://imageshack.us/photo/my-images/266/concreteelevatedway.jpg/)
Title: Re: Bridges
Post by: jamespetts on January 06, 2013, 10:10:48 PM
Very useful!
Title: Re: Bridges
Post by: ӔO on January 07, 2013, 09:45:35 AM
very nice
Title: Re: Bridges
Post by: AP on January 07, 2013, 07:42:43 PM
Nice indeed. :-) A bit too squaky clean, however, from my knowledge of pre-stressed concrete structures! Could they be painted so the grass underneath them goes brown?
Title: Re: Bridges
Post by: Bear789 on January 07, 2013, 10:20:21 PM
Looks good. However, that kind of full pillar will cause graphic problems when crossing diagonal ways on the ground. May I suggest to use a different kind of pillar, like the one used by Pak 64 elevated ways?
Like this ones: http://graphics.simutrans.com/displayimage.php?album=124&pos=11
Title: Re: Bridges
Post by: AP on January 07, 2013, 10:25:01 PM
Actually, if the piers remain linear, can they have an arch through them? So when you double stack elevated ways, or build them along a road, the cars don't drive through the piers? Same goes for brick arches piers, they need transverse arches through the piers.

I keep seeing in game when a railway viaduct has been build directly along a road, it looks very wierd...
Title: Re: Bridges
Post by: The Hood on January 07, 2013, 10:33:25 PM
I did consider that. Part of the problem is the bridge deck is narrower than the road. If you think it would look better with piers strutting out from the deck to make the arch that would work for the concrete ones, and for a steel/iron one I'm planning. However I don't think we have space for the transverse arches in brick pillars: in other words it's not the right type to use in that situation. And I've not seen too many of those either...
Title: Re: Bridges
Post by: AP on January 08, 2013, 12:07:13 AM
Yeah, having googled some more, its not done often in masonry, because there's little point (unless there's something underneath...) and you can't make vastly wide openings, the Ouse viaduct has some of the best relieving arches I've seen - you could drive a bus through them if you were so inclined... (and had extended them to ground...), but i guess not a 2-way road.

(http://www.semgonline.com/structures/pics/gb_ouseviaduct-1.jpg) (http://www.semgonline.com/structures/struct_56.html)

(http://www.semgonline.com/structures/pics/gb_ouseviaduct-5.jpg)


Another example where it was done; Viaducto de los Quince Ojos (although that uses concrete, not true arches). You could get a road through them, though.
(http://madrid1936.es/universitaria/images1/anoscuarenta0002a.jpg) (http://madrid1936.es/universitaria/images1/viaductos.jpg)
Title: Re: Bridges
Post by: greenling on January 08, 2013, 04:18:53 PM
AP
Your Photo looks very gerat out.
Title: Re: Bridges
Post by: The Hood on January 13, 2013, 01:34:39 PM
I've been thinking about this. I agree we need some elevated ways that look good when over the top of ground level ways. However I think the brick elevated ways should remain as they are - at least for rail - given how many of this type we have around in Britain and how few vaulted/cross-arched viaducts we have. I intend to draw an iron elevated way which will have four pillars on tile corners and I will redraw the concrete ones similarly - here's a quick preview (I've only done that one tile and not done any post-processing on the render) - does this work for you?

(http://img692.imageshack.us/img692/2558/elevatedpreview2u.jpg) (http://imageshack.us/photo/my-images/692/elevatedpreview2u.jpg/)
Title: Re: Bridges
Post by: greenling on January 13, 2013, 04:46:04 PM
Woh
The new rail it the hammer. :o
Title: Re: Bridges
Post by: AP on January 13, 2013, 05:09:15 PM
Looks good to me.

Can we have a steel version also (e.g. like the Liverpool Overhead Railway) to fill the 19th-century gap before mass concrete structures?

Regarding brick viaducts, if arches are not being added (fair enough) is there a way to prohibit the building of such a bridge along a road (only perpendicular to it)? I know level-crossings are orientation-sensitive, for instance...
Title: Re: Bridges
Post by: The Hood on January 13, 2013, 05:33:24 PM
Unfortunately there is no way of the game knowing where pillars are at the minute, but I do plan on adding an iron/steel structure which will span roads sensibly. Now I've redone the High Speed tracks I will get producing some more elevated ways. I think doing it as a massive GIMP project and using kierongreen's updated and nicely aligned tracks will be the way forward rather than blender, for consistency. This will mean editing the existing brick elevated way quite substantially first however...
Title: Re: Bridges
Post by: jamespetts on January 14, 2013, 12:25:23 AM
That seems to work for when there is a way underneath - pity that the game can't distinguish at present.
Title: Re: Bridges
Post by: Bear789 on January 14, 2013, 02:05:53 PM
That concrete el looks great.
Title: Re: Bridges
Post by: kierongreen on January 14, 2013, 05:19:33 PM
A great pity I think could be fixed with an entry in the dat. I'll add it to my list of things to do when/if I get time!
Title: Re: Bridges
Post by: The Hood on January 14, 2013, 09:30:32 PM
Latest progress - a range of arched elevated ways created from the existing one with a lot of fiddling around in the GIMP, and combining with kierongreen's new way graphics for extra consistency and perfect alignment of tracks :) I will do bridge versions for each to ensure graphical consistency - the pale on the top to replace the existing masonry bridge and the dark in the middle to replace the existing early brick viaduct.

Now the process is set up it's quite easy to recolour and change brick/track combinations. I intend to do something similar to create the concrete ways consistently.

(http://img713.imageshack.us/img713/8228/archelevated.jpg) (http://imageshack.us/photo/my-images/713/archelevated.jpg/)
Title: Re: Bridges
Post by: jamespetts on January 14, 2013, 09:42:47 PM
Very nice! Any plan to do something similar with aqueducts?
Title: Re: Bridges
Post by: greenling on January 14, 2013, 09:49:17 PM
The Hood
The new bridge looks very good out.
Title: Re: Bridges
Post by: The Hood on January 14, 2013, 09:51:48 PM
Very nice! Any plan to do something similar with aqueducts?

Not really - thought you were looking into doing those as part of your big canal project. I can send you the xcf file so you can see the method and use it if you like. In any case I don't see the same need for canal elevated ways - perhaps one or two but shouldn't need a range of speeds in the same way as rail.
Title: Re: Bridges
Post by: jamespetts on January 14, 2013, 09:56:00 PM
Please do send the XCF - that would be helpful. Canals should in principle have the same range of elevated ways as any other type of transport - certainly, most things that can be a aqueduct should be able to be an elevated way for canals.
Title: Re: Bridges
Post by: The Hood on January 14, 2013, 10:01:36 PM
I'm just working on an equivalent version for bridges, then I'll upload the two together.
Title: Re: Bridges
Post by: The Hood on January 19, 2013, 04:11:46 PM
Quick update: I've now made bridge versions of the xcf files and made new graphics for the three arched bridges so that they are consistent with the new elevated ways. The xcf files are in the git repository. Overview of technique:

For each bridge you need to copy the following layers to a new png file, in this order:
1) background layer
2) track layer (depending on which track colour you want)
3) rail image (depending on which track you want - wssr does not need a rail image)
4) brickwork layer (depending on the colour of the brickwork you want)
5) snow layer (if snow image)

Obviously we can create loads of variants using this. The ones I've done have created the track layers using the colourisation of the tracks from the wssr images as described in kierongreens "New Graphics" thread. The brickwork is altered from the "Brick" layer (the original render output from the original brick viaduct) according to the following settings:

Masonry: colourise Hue: 40 Sat: 25 Lightness 0
Dark Brick: colourise Hue 10 Sat: 40 Lightness -45

Next I'm planning doing a similar trick with the concrete rail bridges in order to create consistent bridge and elevated way graphics for faster tracks, all using the same concrete bridge deck.
Title: Re: Bridges
Post by: jamespetts on January 19, 2013, 06:04:49 PM
Thank you - this is interesting. Might I ask how the technique might be adapted to aqueducts?
Title: Re: Bridges
Post by: The Hood on January 19, 2013, 06:21:45 PM
If you look at the xcf file you will see. For the bridge deck you may be able to reuse the existing layers, or perhaps simply cut and move them wider or narrower (I'm hoping this will work when I come to doing more narrow gauge bridges). Alternatively start with an existing bridge and use the "f" tool to cut away unwanted bits. I'm currently making a new concrete deck in blender, copying the deck into GIMP and removing the central section this way so the track layer will show through. Tracks and deck are obviously on different layers so can be aligned separately, which was something that was not working well when I tried to do everything correct first time in blender.

Obviously you will need to replace the tracks layers with a water layer - for the elevated ways this will simply be a case of copying the entire image from the standard way file (minus background colour) onto a new layer and moving so it aligns properly.

The time-consuming part is setting up the bridge structure/deck - once you've got those in place and copied the way layer, it is quick to produce lots of different graphics.
Title: Re: Bridges
Post by: The Hood on January 21, 2013, 09:15:10 PM
Update: completed concrete elevated bridges and ways. Available in 175, 200, 225, 320 km/h versions to match tracks.

(http://img405.imageshack.us/img405/1791/concreteelevated.jpg) (http://imageshack.us/photo/my-images/405/concreteelevated.jpg/)
Title: Re: Bridges
Post by: kierongreen on January 21, 2013, 10:23:56 PM
Very nice :)
Title: Re: Bridges
Post by: jamespetts on January 21, 2013, 11:26:19 PM
Delightful!
Title: Re: Bridges
Post by: Junna on January 22, 2013, 05:53:33 AM
Have they been added to any source-file library yet?
Title: Re: Bridges
Post by: The Hood on January 22, 2013, 10:52:46 AM
Not yet - I'm still making tweaks and will release all the rail bridges and updated tracks in one large bundle.
Title: Re: Bridges
Post by: greenling on January 22, 2013, 11:53:26 AM
The Hood
The photo from the New concrete elevated bridges and ways are nice.
Title: Re: Bridges
Post by: The Hood on January 25, 2013, 10:11:14 PM
This should complete the rail elevated ways set - an iron girder elevated way and bridge loosely based on the Liverpool Overhead Railway.

(http://img6.imageshack.us/img6/2408/irongirderelevated.jpg) (http://imageshack.us/photo/my-images/6/irongirderelevated.jpg/)
Title: Re: Bridges
Post by: kierongreen on January 25, 2013, 11:04:40 PM
Very nice :)
Title: Re: Bridges
Post by: jamespetts on January 25, 2013, 11:11:15 PM
Splendid!
Title: Re: Bridges
Post by: sdog on January 25, 2013, 11:14:04 PM
This looks very good out!
Title: Re: Bridges
Post by: Combuijs on January 25, 2013, 11:20:16 PM
This looks very good out!

You should go to the doctor, you've walked into a contagious illness   :o
Title: Re: Bridges
Post by: Junna on January 26, 2013, 10:33:19 AM
This should complete the rail elevated ways set - an iron girder elevated way and bridge loosely based on the Liverpool Overhead Railway.


Apropos of the LOR, some units like those originally used on it would be useful as early EMU's.
Title: Re: Bridges
Post by: The Hood on January 27, 2013, 09:20:05 PM
We probably do need some early LOR units for that now. I'll try to remember to draw them when I get round to doing surface stock for the tube. Anyway, here's the latest work in progress - a concrete elevated way for roads ideal for doing motorways with:

(http://img26.imageshack.us/img26/5538/motorwayintersection.jpg) (http://imageshack.us/photo/my-images/26/motorwayintersection.jpg/)
Title: Re: Bridges
Post by: jamespetts on January 27, 2013, 09:30:51 PM
Ahh - Spaghetti Junction!
Title: Re: Bridges
Post by: greenling on January 27, 2013, 09:59:28 PM
Woh
The Hood
You have make nice Roads.
Title: Re: Bridges
Post by: diesseits on January 28, 2013, 04:13:08 AM
@TheHood Excellent. Any hint when these may be included in the nightly build?
Title: Re: Bridges
Post by: The Hood on January 28, 2013, 08:10:33 AM
Fairly soon. For road I want to add a cheap iron girder structure (similar to the one I have just made for rail so it won't take long) and a wooden structure. I don't think there's much need for different road elevated ways as (A) they were not important historically before the motorways came along and (B) most people are more bothered about trains in game. I intend to run an update when I've done those two.
Title: Re: Bridges
Post by: greenling on January 28, 2013, 04:08:51 PM
The Hood
That the Bridge cam soon in the Pakset it Cool.
Title: Re: Bridges
Post by: Bear789 on January 29, 2013, 06:05:20 PM
Looks great!

My two cents about el roads: while definetly not a priority, it can be good to have at least one for each era: they are the only way to build a diagonal bridge, or a bridge that doesn't require a starting slope. Not something that you do commonly, but can be helpfull in some circumstances (for example when you build a railway in a trench through a city).
Title: Re: Bridges
Post by: The Hood on January 29, 2013, 10:42:13 PM
Well, here's an earlier one: a lightweight iron girder road bridge/elevated way...

(http://img221.imageshack.us/img221/5018/irongirderelevatedroad.jpg) (http://imageshack.us/photo/my-images/221/irongirderelevatedroad.jpg/)
Title: Re: Bridges
Post by: jamespetts on January 29, 2013, 11:15:42 PM
Very interesting! Out of interest, are there any specific prototypes for this?
Title: Re: Bridges
Post by: The Hood on January 30, 2013, 08:09:13 AM
Not that I'm aware of - I don't know of too many non-concrete elevated roads. It was just a case of recycling graphics from the railways and the tarmac road - it's certainly a plausible structure.
Title: Re: Bridges
Post by: The Hood on February 10, 2013, 06:32:26 PM
Next one: a wooden trestle road bridge - this will give a continuous range of elevated roadways on the timeline now.

(http://img534.imageshack.us/img534/7964/woodentrestleroadelevat.jpg) (http://imageshack.us/photo/my-images/534/woodentrestleroadelevat.jpg/)
Title: Re: Bridges
Post by: jamespetts on February 10, 2013, 07:53:45 PM
Hmm - did such things exist back then...?
Title: Re: Bridges
Post by: The Hood on February 10, 2013, 08:55:56 PM
I'm sure they did somewhere or other. I can't imagine they'd be particularly useful in game as rails will be far more important, but equally I'm sure there are niche uses.
Title: Re: Bridges
Post by: ӔO on February 10, 2013, 08:59:20 PM
they would be excellent for spanning a bridge diagonally, or making compact bridges that are easier to replace.
Title: Re: Bridges
Post by: The Hood on February 11, 2013, 09:36:09 PM
Here are some narrow gauge bridges - there are also elevated way variants for them:

(http://img706.imageshack.us/img706/7663/narrowbridges.jpg) (http://imageshack.us/photo/my-images/706/narrowbridges.jpg/)
Title: Re: Bridges
Post by: ӔO on February 11, 2013, 09:41:12 PM
that was quick!
Title: Re: Bridges
Post by: greenling on February 11, 2013, 09:44:54 PM
The Hood
The Bridge looks very cool out.
It makes the Narrowgauge more usable.
Title: Re: Bridges
Post by: The Hood on February 11, 2013, 09:54:59 PM
that was quick!

I had all the parts and the xcf set up already from standard gauge bridges - it was just a case of substituting the narrow gauge tracks on the track layer. Unfortunately the wooden one will take longer as it doesn't have a ballast track as a base...
Title: Re: Bridges
Post by: jamespetts on February 13, 2013, 01:29:11 AM
Splendid!
Title: Re: Bridges
Post by: The Hood on February 13, 2013, 10:03:46 PM
And finally, the wooden trestle version:

(http://img38.imageshack.us/img38/9946/woodentrestlenarrow.jpg) (http://imageshack.us/photo/my-images/38/woodentrestlenarrow.jpg/)

That should mean we are complete for bridges on narrow gauge, rail, road and maglev. Just canals - but then I'm not sure there's a huge variation in canal bridges anyway, nor a precedent for elevated canals. @jamespetts, did you get anywhere with graphics for these with your canal overhaul (processed or unprocessed)?
Title: Re: Bridges
Post by: jamespetts on February 13, 2013, 10:26:48 PM
Looking good!

I was rather relying on TygerFish to process the canal graphics. He made a start, but I haven't heard from him in quite a few weeks. We hadn't even started on aqueducts, waiting for the base canal graphics. I am rather buried in bugfixing in Experimental at present (plus working on improving the balance and addressing passenger generation and related issues) so might not be able to get around to this for a while.
Title: Re: Bridges
Post by: The Hood on February 14, 2013, 09:40:02 PM
Did you add the graphics somewhere to github? I can't find them easily. Happy to process up any existing graphics for canals and possibly produce one or two bridges/elevated ways for them as long as they fit the existing patterns (e.g. arched style, concrete, iron girder etc from the rail/road bridges I've done recently - that wouldn't be too much work) - what did you have in mind?
Title: Re: Bridges
Post by: jamespetts on February 15, 2013, 12:00:53 AM
The unprocessed images for canals are here (https://github.com/jamespetts/Pak128.Britain-blends) (not in the /boats directory, but in the root directory). I hadn't yet planned what sort of aqueducts to have - I imagine that masonry, stone, and one that looks a bit like this (http://en.wikipedia.org/wiki/Pontcysyllte_Aqueduct) would be a good start, as well perhaps as a mixed wooden/stone version for smaller canals, and concrete versions for modern times. I don't think that we need canal based elevated ways, as there are no historical precedents for this so far as I am aware. I am fairly sure that it would suffice just to make canal versions of the existing bridges, however, if modelling the Pontcysyllte Aqueduct is a bit much, although I do not think that all the bridge types would need to be done (especially all the various metal types).
Title: Re: Bridges
Post by: Milko on April 19, 2013, 02:57:22 PM
Hello

I can not find this bridge http://forum.simutrans.com/index.php?topic=8755.msg82771#msg82771 in pak128brit 1.14 and in pak128brit experimental (last github commit).

Giuseppe
Title: Re: Bridges
Post by: jamespetts on April 19, 2013, 09:18:57 PM
It is the iron arch bridge - it should be there. Note that the decoration on the arch is in player colour, so the colour on your bridge might be different to what you can see linked in that post.
Title: Re: Bridges
Post by: The Hood on April 21, 2013, 08:57:47 PM
The dat file is certainly there in Standard SVN - iron-arch-rail.dat