Map of rivers and canals in the British isles

[jamespetts]

I thought that some people might find useful this map of rivers, streams and canals in the British isles: it gives a good idea of what a system of rivers should look like if one is aiming for realism in one's calibration of the various river settings. Don't forget to take into account the scale of the map in comparison with the scale of most Simutrans maps (explicit in Experimental, implicit in Standard).

I wonder whether there might be some scope for tweaking the river generation algorithm in light of this to generate more streams per river, and more medium sized rivers to large rivers...?

[AP]

Interesting to note how few canals reach London from the midlands (2 by my count).

I agree more rivers on a map would be excellent. We do however still need flat river bridges (for both road and rail) - the absence of these will become more apparent the more rivers there are, especially if a player tries to engineer flat routes (as is my preference). It is very annoying to have a route entirely level across the map except one river crossing!.

[kierongreen]

Could have a level river/road and river/rail crossing for small rivers which looked like a bridge
--
Also it's worth noting that England, despite having rolling hills rather than mountains still has a transport network limited by geographical features. There's only two main routes from London to the Midlands - one taken by the Grand Union Canal, London and North Western Railway and the M1 (and prior to that the A5 and Roman Watling Street) through Watford Gap, the other by the Oxford Canal, Great Western (later shared with Great Central), and M40 past Banbury. So it should be that much of a surprise that there are only two canals, as there are only two motorways and two railways also

[jamespetts]

I don't think that the lack of flat river bridges is an issue. In hilly countryside, rivers in Simutrans, as in real life, carve themselves out valleys and it is possible to bridge them on the flat if the railway/canal/road/etc. is on the level above the valley. In flat areas, the rivers are the same height as the surrounding terrain, just as in real life, and one has to bridge them by increasing one's height, just as in reality.

The issue will be mitigated somewhat when Kieron's new landscape patch is added, if that patch allows for bridges built on the flat to have half-height slopes. I am not sure whether it does that, however.

[AP]

I don't think that the lack of flat river bridges is an issue. In hilly countryside, rivers in Simutrans, as in real life, carve themselves out valleys and it is possible to bridge them on the flat if the railway/canal/road/etc. is on the level above the valley. In flat areas, the rivers are the same height as the surrounding terrain, just as in real life, and one has to bridge them by increasing one's height, just as in reality.

The issue will be mitigated somewhat when Kieron's new landscape patch is added, if that patch allows for bridges built on the flat to have half-height slopes. I am not sure whether it does that, however.

Possibly - I just know that I've had it regularly on maps with many rivers where railway runs entirely at level 0 and encounters river running on level 0. Clearly one can't lower the river, ergo a raised railway bridge (which is bad for trains). The more rivers you have,  the more levels they occupy, such that there is less chance of finding an optimum level that can be engineered to bridge them all. Offline I resort to importing the pak-128 lifting bridge, but I don't think a swing bridge (or bascule bridge for canals) would be out of the question for pak-gb. There are plenty of precedents:

Oxford (so close to water level the barges can't fit under it)
Trowse (electrified on the GE Main Line)
Barton (Manchester Ship Canal)
Somerleyton & Reedham (Norfolk Broads)

For streams, a road/river crossing could even be painted as a ford...

--
Also it's worth noting that England, despite having rolling hills rather than mountains still has a transport network limited by geographical features. There's only two main routes from London to the Midlands - one taken by the Grand Union Canal, London and North Western Railway and the M1 (and prior to that the A5 and Roman Watling Street) through Watford Gap, the other by the Oxford Canal, Great Western (later shared with Great Central), and M40 past Banbury.

True that. There was also a 3rd route taken by the GCR (before it closed) which looks to be re-used by High Speed 2, in both cases because it avoided all the intermediate towns.

[kierongreen]

The issue will be mitigated somewhat when Kieron's new landscape patch is added, if that patch allows for bridges built on the flat to have half-height slopes. I am not sure whether it does that, however.

It doesn't directly (in pak128.Britain). Half height bridges can start off slopes however. To further complicate matters though any bridge crossing a way (including rivers) must have a 2 tile height clearance so that vehicles can travel underneath it.

[jamespetts]

The problem with the crossings are that, for rivers, they are cheats - they are coded so as to be more like fords: they do not have any of the expenses associated with bridge building. Clearly, railways never had fords, so this would not work for realism.

It doesn't directly (in pak128.Britain). Half height bridges can start off slopes however. To further complicate matters though any bridge crossing a way (including rivers) must have a 2 tile height clearance so that vehicles can travel underneath it.

Interesting. That is a worthwhile addition. So, one could cross unnavigable streams or rivers that one does not wish to navigate with a half-height bridge banked with a pair of half-height artificial slopes?

[Carl]

This is a wonderful resource - thank you!

[kierongreen]

So, one could cross unnavigable streams or rivers that one does not wish to navigate with a half-height bridge banked with a pair of half-height artificial slopes?

I would need to add code to allow this possibility (and to prevent unnavigable streams being upgraded to navigable ones if a low level bridge crossed over). It should also be noted that at present all bridges look at least 2 tiles high even if they are only one tile high as I have not added extra graphics for single height bridge tiles or coded for this.

[AP]

If the code is being reworked, is there any chance of us getting opening bridges (or making provision for them)? Or is that a can of worms best avoided?

[jamespetts]

I would need to add code to allow this possibility (and to prevent unnavigable streams being upgraded to navigable ones if a low level bridge crossed over). It should also be noted that at present all bridges look at least 2 tiles high even if they are only one tile high as I have not added extra graphics for single height bridge tiles or coded for this.

Ahh, I see - is it simply coded that all bridges must have a full/double height tile differential so that the existing graphics are used?

[kierongreen]

is it simply coded that all bridges must have a full/double height tile differential

Not quite! Bridges starting/ending on flat terrain must have a full height slope at the beginning/end, but other than that there are no limitations on whether the rest of the bridge is single, double or more high. However the graphics don't exist to show single height bridges correctly so these will appear to be double height even though they are actually single height (the bridge deck will be at the correct height, however pillars may extend into the ground). I hadn't gone to the trouble of altering bridge display code as my feeling was that it's likely that bridges will be revisited sooner rather than later to add more complex bridge designs.

It should be noted that all these problems don't apply if my patch is used to give steeper slopes (as prissi plans for pak64) rather than shallower ones (as I chose for pak128.Britain).

[jamespetts]

I think that I prefer your shallower version; but would it not be wise, at least until bridges are re-coded, to prohibit single height bridges for which there are no graphics?

[kierongreen]

Not in my opinion. Just an opinion, it's not an ideal situation I know.

[jamespetts]

Why do you not think that it would be better to limit single height bridges for which there are no graphics until the bridge system is recoded to allow for them?

[kierongreen]

As I said, not an ideal situation. Either you allow them, and tolerate graphical inconsistencies, or forbid them and make it more difficult to construct bridges. I prefer tolerating the minor graphical glitches for now.