====== ArmA 1 Visitor 3 Terrain Erosion ======

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**ArmA 1** aka Armed Assault (ArmA)

**Visitor 3 Terrain Erosion feature**

This feature can be found from the terrain matrices menu, you need to choose area of terrain cells to work on (usually all with CTRL-A).

Please note that Visitor 3 is very slow to compute on large terrains, so please give it good time as it runs if your terrain is large.


====== Functions ======

**nGens**: 0-128.

Since the ofp map square is 128x128m wide (wasn't it), I presume this is how many smaller plains you fit into it in terrain detail levels... in buldozer the squares show up as rough 50x50, it's totally different in game. //as you see this was quite OFP comment.//

**WashCoef**: 0-1.

The first eroding factor. I use very minimal values, and this has 0.006. Don't know what exactly this does. 

**SedimCoef**: 50-300.

This factor does very little AFAIK (with settings I use). I can even use 300 and I don't see any difference.

**SedimBase**: 0-1.

Perhaps the most important factor. This determines the hardness of the surface. I use 1 to achieve minimal height alteration. 

**SedimEff**: 0-1.

Almost same as above AFAIK. I use 0.9

**InitRain**: 0-1.

The most eroding factor with the last one. I use 0.006 to achieve very round shapes together with the before mentioned settings. 

**SteadyRain**: 0-1.

Hard to tell the difference between this and the above rain. Might be even harder eroding. I use 0.001. 


====== Findings ======

**sedimbase** and **sedimeff** is how smooth erosion is, 1 is smooth, 0 is very rough.

VTE terrain erosion (Vietnam 25km, no slowdowns in old OFP version).

^ Function ^ Value used ^
| nGens | 64 |
| WashCoef | 0.006 |
| SedimCoef | 150 |
| SedimBase | 1 |
| SedimEff | 0.9 |
| InitRain | 0.4 |
| SteadyRain | 0.4 |

This following was tested on 51km afghanistan terrain, here is the results. Use the other values from the above table, these are the changes and results:

^ SedimBase ^ SedimEff ^ Results ^
| 0.5 | 0.5 | too heavy jigs and jags, perhaps for pure aircraft map |
| 0.7 | 0.7 | still very very rough |
| 0.8 | 0.8 | hmm pretty ok still, quite waves from mountains down |
| 0.9 | 0.6 | still too bad :) |
| 1 | 0.6 | pretty hardcore |
| 1 | 0.9 | ok I guess |