66 replies to this topic

[Cartesian]

Some properties of lasers thhat affect gameplay and hence are of immediate importance. Deimos has said moslty everything, but I think there are som points that need to be clarified.

All laser weapons that are going to have to supply a large amount of energy in a small amount of time. No power supply can provide the energy required contineously, so the weapon powers up and then emits a burst for a short duration (say a ns/ps/fs), and this burst is focused over a small area, giving a large intensity. there is a recharge time inbetween bursts where capacitors charge up to provide enough the potential to power the weapon.

So between the overheating and the charging up time we have a reason why the laser is bursty.

Lasers pulses travel at the speed of light. Wind and gravitational effects can be neglected in the battlescape. Enemies cannot dodge the pulses. These factors mean the accuracy will be greater than any other weapon system.

laser pulses are by and large invisible, in that they cannot be seeen by the naked eye. The only time you 'see' a laser in when reflected light scatters from some objet/medium.

you wouldnt have a targeting laser for a laser since you would just have a scope. the light travelling from the target to the scope takles exactly the same path the light from the gun to the target will take. One is passive, one is active. You do not use active systems is pasive systems perform the same job. Perhaps you could turn on the targetting laser for a 5% increase in accuracy for snap shots? (thats assuming the aimed shot uses the scope, so no bonus, and auto fire is reasonably wild).

smoke will now beccome a major part of the battlefield. instead of just obscuring vision, it will obstruct laser as well. the lasers will become visible alerting the enemy to an attack, and the attack will almost certainly fail since the majority of the light will be scattered.

light doesnt knock down doors or chop up buildings. if the laser doesnt do this anymore (it does in ufo1) then other weposn such as the autocannon will become more useful sicne it will be used to create alternative entrances to buildings/clear foliage.

[A_dxman]

its good to see someone knows their stuff.
Your right.
we dont need a big explanation, but we do need some, and i think tha tthe original ufopedia was lacking in this department.
i just think that some reality should be brought to the weapons, base them on real facts, or, some of them at least.
oh and BTW whats with the dig at trekies?
I AM a trekie!
i just think that human lasers should be based on X-rays cause we do actualy have x-ray weapons, and not just the kind that increast the chance that you will get cancer in twenty years time!!

Edited by A_dxman, 03 November 2003 - 10:26 PM.

[Cartesian]

I'm noot sure if this is entirely the correct thread for this, but its been brought up here before...Aesthetics vs realism:do we want no beam, or do we want red beams?

well, why not give the user the option? let them turn it on or off at will. ie, make a normal beam, and give it the user defined property of alpha=50% or alpha=100% along with ther user defined things such as alien run speed etc. in fact, why not allow the user to define the colour entirely of the laser beams?

I know that in SP id like to have red/yellow beams (cos they look cool), but in MP ill be using transparent ones so that I can retain the element of stealth.

another thing: lasers DO NOT leave visible trails through standard atmosphere. They might ionise the air depending on whhat frequancy of light is used, but in that case, you have ionised transparent air.

even worse than having the fiction that lasers can be seen would be to invent a new one.

Edited by Cartesian, 03 November 2003 - 11:03 PM.

[Cartesian]

Plasma weapons: oh dear. basically as it stands according to my knowledge the plasma weapons from ufo1 are impossible. you just dont get blobs of plasma that are coherent like that in real life. the plasma cannon would be at best a plasma "watergun" or a plasma "flamethrower".

what was posted earlier is esssestially correct: take a gas, heat it up, squirt it out. the closest "real life" analogy is the vasimr rocket.

If one wanted a non dispersive plasma round, I'd suggest a small solid shot of something, (maybe iron?) which gets heated up (from some process involving elerium) and ejected electromagnetically. So this is effectively creating a rifle which fires very hot rounds. ho hum, nothing interesting here and this is great since its believable.

[A_dxman]

setting the colour is a good idea but if you let the gamer set the colour then it would only impact the game in that it LOOKS diffrent, it wouldnt effect the game.
if you made in transparent and that made you stealthy, then you would need to 'pay' for that in some way.
Let the gamer pick the colours for their stuff (Like in AOE (1 or 2) or homeworld (1 or 2))

[Cartesian]

Lasers can use any ppart of the spectrum. There are going to be some that are useful, and some not so useful.

Take for example:

Microwave flips the spin on polar molecules such as water, which heats it up.

infrared vibrates molecules and atoms around lattice positions heating...

UV is at the resonant frequency of electron spin flipping it is readily absorbed.

gamma rays can readily remove electrons from near the nucleus so this ionises atoms.

gamma rays willl pass through multiple targets.

so there si a question of what frequency one wants the laser to emit at, but i think the point is largely moot since in game terms its lighht and it kills stuff.

[Cartesian]

if the default is invisible, then everythignis fair and physically realistic. Note that this invisibility does not include the case of the laser travelling through a dispersive medium such as smoke. in that case, even if the laser is "invisible" by deafult, it will show up in the smoke.

since the aliens never use laser weaponry, and the ai can simply be programmed not to recognise it, it would be purely for the gamers enjoyment to have coloured laser beams, and if they didnt want colourd laser beams they could not activate that feature.

btw: the whole "realistic vs fun" thing will come up a lot in future discussions about bullets, damage, explosions, etc. i think the only way to resolve all of these difficulties is to let the gamer choose how to view the game.

[Cartesian]

I noticed railguns above: Recoil is a big problem (along with barrel scouring, heating, energy consumption).

There wont be a man portable rail gun for a wee while and when there is it wont e substantially better than a standard combustion firearm.

The rail gun will fire a metal slug of rest mass m at a velocity v. Special relativity can be ignored for v up to about 1/2 the speed of light and since the power required to do that is enourmous, we can safely assume that the xenocide wont worry about that issue. we therefore only have to worry about normal newtonian mechanics.

ignoring all other issues, momentum transfer is a large issue. this would mean that the railgun would be tank mounted, which isnt so bad since it really is akin to an artillery piece. if this is going in xenocide then we can have some cool trail effects (kinda liek those in Q3, they werent so bad) to go along with it, in addition to a large sonic boom.

its only really worth talking about the penetrating effects of this gun once the model of physics used in the battlescape has been determined.

[Cartesian]

Lasers should have infinite ammo like ufo1. it is one of the major things that i love about it...

One of my favourite fun tactics was lining up my guys and autofiring into a building trying to kill the aliens insde.

Edited by Cartesian, 03 November 2003 - 11:36 PM.

[red knight]

I was going to mention it, in the programming wise part of the project on the mailing list... for any gameplay related idea, a Laser with 200 shoots it like infinite, but thinking of a human made weapon that use energy and infinite charge, I dont think so...

Greetings
Red Knight

[Breunor]

It's either in the HWP thread or cyberdisk thread, where a concept picture of a plasma round is located that it seemed eveyone liked. A blue lightning ball type of effect, representing a magnetic field that holds the plasma together for the few yards it travels outside the barrel. Since the plasma weapons require elerium to make, we dodge the reality bullet by saying elerium allows the powerful magnetic field and plasma it holds to be created within a relatively small chamber, etc.

As for the laser turret, we have decades of popular culture saying a laser should be a colorful beam of goodness shooting in a straight line at the target. I think a solid line from the barrel to the target would look good, rather than a short piece that travels from point A to B.

[Cartesian]

Red Knight, if you read the tech docs floating about the net on the new LFLAN proposals you'll see that the proposed persnoal handheld laser weapons have extremely "large clips". For instance the stavatti TIS-1 proveides ccontineous energy and hence weapon use for over 60days. I agree that this is not infinte, but in game terms where a battlescape might last 6 hours there is no way a soldier can discharge the weapon.

Calculating the shots provided by the data on the stavatti design we should see a theoretical min of 7200 bursts per power source, up to a theoretical maximum of 1,224,000. The other thing to note is thaat in this design, one cannnot remove the clip/power source and add another, I imagine it'll have to be replaced off field.

In both cases though one would hardly call either finite in terms of a battlescape.

One of the things that sucked badly play wise in UFO2, UFO3 was the lack of the laser rifle with its yelllow beam and inifite ammo. Lets not make the same mistake. Or how about letting it be user defined at the start of the game?

[Cartesian]

Breunor, you cant get a magnetic field around a ball (basic example of stoke's law (related to stoke's theorem)).

well you might be able to wrangle it if you had 2 magnetic monopoles, but no one has EVER detected one (and they do look). think of the incident that took place at tunguska. ppl has hypothesised that this might have been a magnetic monopole intersecting the earth. it not the sort of thing one has in a gun. The end result is that that suggestion, as tempting as it is is not physically based.

this is essentially why I didn't sugggest a magnetic ball holding in the plasma. A plausible explaination mighht be a solid slug of metal, with the surface heated up to plasma temperatures by an elerium power source (it would require a fair bit of power to ionise a hunk of metal). This can then be ejected from the rifle in everyones favourtie railgun/coilgun method.

the end result is a hot blob of metal that travels quite quickly. It'lll burn stuff, knock holes thru stuff, if it impacts a solid object, it'll deform over the surface releasing a stupid amount of heat into the target almost certainly destroying it...not quote your sci fi plasma gun, its a real plasma gun! There are obviously large technical difficulties in actually building one along with diminishing returns, which is why we dont try to make them in reality (yet).

EDIT: Oh yeah, this requires a clip of ammo since somethig has to be ejected from the weapon. We could make the requirement that the material be specially shaped and of certain megnetic properties so that soldiers on the battle field cant shove anything in.

Edited by Cartesian, 04 November 2003 - 06:23 PM.

[Breunor]

I'm thinking that RK meant that having every weapon include a finite amount of ammo would be helpful in regard to coding? And making that amount really high would be the equivalent of unlimited? 200 could be the same as 2000, or 20000? Maybe I'm wrong but I think his point was that there needs to be some number in there?

As to the magnetic field holding the plasma, and as to what the projectile consists of, there had been talk about writing in a bit about elerium being very stable except when in contact with a particular element, and by mixing the two during a firing sequence you'd get the high powered reaction needed to work the sci-fi magic. Maybe it's this element that becomes the projectile as well? It could be something common on Earth but not in the atmosphere, something not present in the alien world. Can we write up something that sounds "possible" along those lines? IMO there will need to be some flexibility with the reality aspect of it, maybe the tunguska incident was the result of elerium coming into contact with the mystery element for the first time? It's always fun to tie in historical mysteries with the game.

[Nurrin]

this is essentially why I didn't sugggest a magnetic ball holding in the plasma. A plausible explaination mighht be a solid slug of metal, with the surface heated up to plasma temperatures by an elerium power source (it would require a fair bit of power to ionise a hunk of metal). This can then be ejected from the rifle in everyones favourtie railgun/coilgun method.

Cartesian got me thinking, why couldn't the plasma gun's clips be filled with 'elerium' slugs which are loaded into the chamber where they start to become unstable. During this process they would be spun on an axis at extreemly high speeds to keep the 'ball' of plasma coheirent while it continues to degrade on it's way to the target? Course, that means the plasma gun could have a finite range to it, where it would just dispirse conicaly hitting anything around it's end destination in a spray pattern... but that holds potential as well. :-)

[Xer0]

I heard the military (i.e. the U.S. military) actually looked extensively into lasers.  It was found that a "laser rifle" kinda thing was doable, but not practical (the battery was a little big to lug around, or whatever).  On the other hand, they found that a wide beam, portable blinding laser turret kind of setup would be very efficient, but...er...not exactly ethical.  You know, permanently blinding everyone on the other side of the battlefield.  Don't ask my why bombing them is better.  This is all hearsay anyway, I dunno.

Yes, and there is also the problem of cooling. A cooling system so small as to be in a pistol would be inefficient, beacause after a few shots of the laser, the gun would be much too hot to hold. However, a craft-based laser, such as on a battleship, would be very possible with a large cooling system, maybe one using liquid nitrogen. The downside would probably be that the laser would need to charge.

Also, the laser would indeed be invisible. The visible light spectrum has an energy wavelength range of approximately 400 to 700 nanometers, 400 being the highest energy (violet) and 700 being the longest wavelength with the lowest energy (red). ROY G BIV if you will.

Now X-rays and Gamma rays are much higher energies than the light in the visible spectrum, so yes, they would be invisible. A Gamma ray is quite intense, and maybe that would be a better and more realistic choice than a laser as a weapon.

But still, the problem relies on methods of control.

Edited by Xer0, 28 February 2004 - 07:26 PM.

[Robo Dojo 58]

Yeah, gamma rays are very hard to control. They can go through several feet of concrete, and it easily destroys organic life. The most common modern source of gamma rays is from radioactive decay. And space.