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1. Hi all.
I come here and look for help:

I created my own bisurf files, which work very good:
Originally Posted by [b
Quote[/b] ]Density = 10;
rough = 0.6;
dust = 0;
bulletPenetrability = 400;
soundEnviron = "Empty";
isWater = "false";
friction = 0.6;
restitution = 0.3;
impact = "default_Mat";
They must be applied in the Fire Geometry, and here is my question:

I made a chain fence, and I would like to create the effect that when you fire through it, then you have the sparks on the chain.

To make this, I created the fire geometry, a simple fire geo, and I applied the Rvmats linking the bisurf file: AI don&#39;t shoot through it (because of the FIRE GEO LOD).

But... is there a way that via bisurf file, I can make the Ai understand that the Fire GEO LOD is penetrable? So that it can shoot through it?

2. That is a very good question Linker my friend. I have had a look at it and think I have a way around that limitation.

I am going to base my solution on probabilities. If you fire a weapon through a fence the probability of it actualy hitting the wire is 50% and if the bullet does touch the wire it will continue traveling and hitting the target (with a little defflection).
Due to the limitation in ArmA, if you put up a solid component in the FIRE GEOMETRY LOD it prevents AI from shooting through the object even with a .bisurf definition attached.

So here is my solution.

add some components spaced out along the length of the fence as above to the FIRE GEOMETRY LOD and apply the .bisurf definition .rvmat to all the components. Now AI can see it as being able to shoot through the fence. 50% of the time the bullets will hit the components but due to the .bisurf definition the bullets will penetrate through the fence and hit the target depending on your penetration specs and 50% of the time the bullets will travel clean through without touching anything. This way you can add custom hit sound and effects and keep a very realistic fence penetration effect. I think if you play around and test the spacing between the components you would get a good probability of pass and penetration. You could make the components narrower to increase probibility of bullets passing through fence. The whole idea is to get AI to fire through fence at a target and get the effect you require.

Hope this idea helps, I tested this theory quickly and it works quite well.

3. Could this be used to simulate soft armour on vehicles? Like vehicles that can be penetrated by 12.7mm weapons.

4. ingenious solution

5. Originally Posted by (MehMan @ May 12 2008,15:14)
Could this be used to simulate soft armour on vehicles? Like vehicles that can be penetrated by 12.7mm weapons.
Actualy this solution is intended for an addon that is not a target and only to be fired through. I do not want to high-jack Linkers thread here as Surface penetration is a subject on its own... but will explain a little about .bisurf files.

A vehicle is seen by AI as a target so what you want to do is give the "Armour" of your addon in the FIRE GEOMETRY LOD a penetration value to be used by the game engine. So that bullets are able to penetrate and kill the ocupants before the vehicle is completely destroyed.

There are certain values that ArmA uses and I am going to give some samples to explain. I am also assuming you know how to implement and apply the .rvmat files in O2.

The following definitions are standard ArmA .bisurf penetration values.

armour.bisurf (standard ArmA tank armour value)
Originally Posted by [b
Quote[/b] ]
Density = 7840;
rough = 0.1;
dust = 0;
bulletPenetrability = 1;
soundEnviron = "Empty";
isWater = "false";
friction = 0.7;
restitution = 0.3;
impact = "default_Mat";
metalPlate.bisurf
Originally Posted by [b
Quote[/b] ]
Density = 7800;
Thickness = 1;
rough = 0.1;
dust = 0;
bulletPenetrability = 20;
soundEnviron = "Empty";
isWater = "false";
friction = 0.7;
restitution = 0.3;
impact = "default_Mat";
wood.bisurf
Originally Posted by [b
Quote[/b] ]
Density = 600;
rough = 0.1;
dust = 0;
bulletPenetrability = 150;
soundEnviron = "Empty";
isWater = "false";
friction = 0.7;
restitution = 0.4;
impact = "default_Mat";
You will notice that the different materials have different values. The important deffinitions to look at are;

Originally Posted by [b
Quote[/b] ]
Density = (Material density an ArmA game engine calculation, need to look at .bisurf files for the various standard values)

Thickness = (Material thickness in milimeters if it is a plate or surface eg. 1)

bulletPenetrability = (values from 1 - 3000, 1 being the least penetrable and 3000 being the most penetrable)
in the case of your addon I would make the FIRE GEOMETRY LOD and make the following .bisurf and .rvmat file.

my_Plate.bisurf
Originally Posted by [b
Quote[/b] ]
Density = 7200;
Thickness = 5;
rough = 0.1;
dust = 0;
bulletPenetrability = 150;
soundEnviron = "Empty";
isWater = "false";
friction = 0.7;
restitution = 0.3;
impact = "default_Mat";
and the .rvmat file would look like this

my_Plate.rvmat
Originally Posted by [b
Quote[/b] ]
diffuse[] = {1,0.5,0.5,1};
ambient[] = {1,0.5,0.5,1};
VERY IMPORTANT
In O2, first select the entire selection in the FIRE GEOMETRY LOD then apply Structure/Convexity/Component Convex Hull

Then you goto Face Properties/Material dialogue and define the path to the material file eg. my_Plate.rvmat file to all the components that are " vehicle armour"

Thats it... now you will have a vehicle with penetrable armour, you will need to test the different calibers and adjust you bulletPenetrability = value to obtain the desired penetrability (the higher the value the more penetrable the material will be.) for the different calibers.

6. That&#39;s what i did m8 of course, as you have suggested, it&#39;s the only way to avoid that problem

thanks anyway

7. Originally Posted by (MehMan @ May 12 2008,06:14)
Could this be used to simulate soft armour on vehicles? Like vehicles that can be penetrated by 12.7mm weapons.
Unfortunately, surface penetration is rather limited.

A bullet&#39;s speed determines how well it penetrates, nothing more. So a .50 cal bullet isn&#39;t going to penetrate as well as a 7.62mm bullet, due to the higher speed of the 7.62mm round.

Also, the thickness of the surface in the fire geo LOD is what determines the surface thickness, not anything in the .bisurf file.

8. Originally Posted by (General Barron @ May 13 2008,02:11)
Also, the thickness of the surface in the fire geo LOD is what determines the surface thickness, not anything in the .bisurf file.
You are quite right with your statement, however the Thickness = value in the .bisurf definition is merely an indicator to the game engine if the material is a solid or a plate and if it is a plate, how thick? I think that we will be able to use the .bisurf more effectively in ArmAII as it is quite limited at the moment as you mentioned.

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