Guides:Landbridges
The art of making LandBridges
A lot of people complain about this type of bridge, but until we have proper bridges (and maybe boats) they are our only way to connect two landmasses.
Find best place
The best place for a landbridge is the shortest distance between 2 shores, but it is better being in a straight line than going diagonal.
Water Depth
Depth of water is a big factor as dirt "flows" when a slope get to 40 (4 meters), what i mean by "Flow" is that the dirt will slide down the slope until it gets to a lesser slope.
How to tell what a slope is.. Well examine the Tile border, but dirt will also flow if the diagonal of the tile is over 4 meter slope as well.
As part of planning a LandBridge, it maybe a good idea to estimate the number of cartloads required. This should be easy, all you have to do is work out how many dirt you need to drop on each corner of the tiles to raise it above water level. Note don't take into account the dirt flow.
How depth affects the dirt flow
Any dirt dropped will flow to adjacent tiles keeping a maximum slope of 40...
The problem is that the dirt flows out in all eight directions so...
A---B---C---D---E | | | | | F---G---H---I---J | | | | | K---L---M---N---O | | | | | P---Q---R---S---T | | | | | U---V---X---Y---Y
so if this area was flat and you dropped 40 dirt on corner M, it would just pile up, but if you now dropped 9 more there then it would raise corners G,H,I,L,N,Q,R,S and M up by one dirt. So to get corner M 80 dirt higher that it started you need to get corners G,H,I,L,N,Q,R,S up 40 dirt each, so you would have had to drop 400 dirt.
So to raise corner M up 120 dirt, then you need to get all corners 40 up, + 40 more for the middle ones + 40 for M = 25 * 40 + 9 * 40 + 40 = 1400 dirt (35 cart loads).
Example: Vires LandBridge
So for the Vires LandBridge, the depth was, on average, 70 dirt (less than 2 cartloads), and the bridge was/is 30 tiles long.
Next decide if you want to do a one tile or two tile wide LandBridge, a one tile wide LandBridge will be affected by dirt flow, where as a two tile one is not (if done correctly).
So for the Vires LandBridge...
- One Tile Wide... As dirt flow has to be taken into account then, if you only drop dirt on one side of the bridge, it would use 140 dirt (70 + the 30 dirt that flows, so have to count the 30 twice in this case + 10 from dropping dirt) for one side and 70 dirt for the other side = 210 dirt per tile forward. Overall... 210 * 30 / 40 = 158 cartloads
- Two Tile Wide... As there is no dirt flow (if done correctly) then, as there are 3 corners, its 3 * the 70 = 210 dirt per (two) tiles forward. Overall... 210 * 30 / 40 = 158 cartloads
So looking at that, a 2 tile wide LandBridge would take a fraction more than a one tile wide one upto an average depth of 70 dirt. So if the deepest part is over 100 deep, then i would recommend a 2 tile wide one.
The decision for the Vires LandBridge was for a 2 tile wide one as it looks a lot better than a single tile (also some tiles were a lot deeper than 70).
It's also easier to slip off a one tile bridge, so a 2 tile bridge is more convienient to use.
Enough of deciding what type of LandBridge to go for... Here is how to do one
How to do it
- Single Tile width (wasting dirt!) Drop dirt on each corner off the deep end of the LandBridge to bring each corner upto the same height.
- Single Tile width (Not so much wasted dirt!) Drop dirt on the left side of the tile off the end, when its above water, flatten the tile, repeat until both front corners of the tile are above water.
- Double width (No wasted dirt!) Plan...
+---+---+---+ | 1 | 3 | 5 | +---A---B---C | 2 | 4 | 6 | +---+---+---+
Evaluation...
A B
+---+---+
\
\
\C
+
If slope from B to C is greater than 20 then
- Drop 20 dirt at the intersection of the 4 tiles at point A (center of bridge!)
- Flatten tile 3
- Drop 20 dirt at the intersection of the 4 tiles at point A (center of bridge!)
- Flatten tile 4
Otherwise (as slope is less than 20, dirt will not flow off end)
- Drop 20 dirt at the intersection of the 4 tiles at point B (center of bridge!)
- Flatten tile 5
- Drop 20 dirt at the intersection of the 4 tiles at point B (center of bridge!)
- Flatten tile 6
When tiles 5 and 6 are above water, repeat the process by moving along one tile
Notes
Flattening in water...
- The maximum that someone can flatten is 3 * their skill level - So for someone with 20 skill their max would be 60 dirt (6 meters)
- Flattening will stop when ...
- The highest corner is 5 dirts below the water level
- You run out of Stamina
- The tile is flat.
- For best results try to keep the whole LandBridge 3 dirt above the water level, pack it and pave it (then you should not get any water showing through).
Tips
- If you cant flatten a tile because you dont have enough skill, drop dirt on the lowest point
- When flattening, don't stand on the highest point as you may get "Ouch that hurt!" (multiple times)
To meet Wurmpedia's quality standards, this article or section requires a cleanup by the Wurmpedia Team.Template:Copyedit --Tich 02:27, 22 January 2007 (CST)
