Author Topic: Need info on plasma-projectiles  (Read 219 times)

tob.s

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Need info on plasma-projectiles
« on: December 07, 2016, 12:21:20 am »
Hi,

currently my plasma-turrets use triangulation or the altitude difference based maths for vertical aiming - both methods ignore gravity though, which easily could lead to missing even a stationary target at above medium distance.

so currently im trying to use the same ballistics i used to lob the grenades in the video below to aim with a plasma cannon. I determined the speed of the plasma by firing backwards from a plane - around a speed of 75 the plasma drops almost vertical from the plane, so i fed my maths with v=75. Also, plasma seems to be floating / not fully affected by gravity - i reduced it to half witch seems to work, to realy be sure ill need to build a much larger test-map though. Atm im still using the formula for targets at the same altitude, as the error is minimal when firing in an high arc.  Now with plasma though, the arc is very flat, so im currently searching for the correct formula.

as i renember, xfm tweaked the plasmas behaviour - so the correct values might have been posted somewhere back then. If someone knows the exact values it would be a big help.


PressureLine

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Re: Need info on plasma-projectiles
« Reply #1 on: December 07, 2016, 01:32:49 am »
From memory you can take the shoot force and divide it by 39.5 (or a similar number) to get the velocity of the projectile. I do have a ballistic calculator level saved (it operates at about 0.8G though, like most blueshift-based maps) that I can upload tonight if you want.

For a combat bot I usually just pre-compute (using the ballistic calculator at a given capacitance and distance [usually 250]) then do
Code: [Select]
(distance to target/pre-computed distance)*pre-computed angleto get the superelevation angle, then do straight altitude based calculation to get the straight-line angle between the cannon and the target, add them together to get the total angle required. That will usually generate a hit on a bot-sized target at a reasonable range (just a reminder that this is based on using a blueshift-based map, where the distance between targets and the altitude difference is not affected by the spherical gravity field of a planet)
"Never assume that anything you've never seen before is benign. Most particularly not something that says 'MARINES' on it."

tob.s

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Re: Need info on plasma-projectiles
« Reply #2 on: December 07, 2016, 03:05:04 am »
thanks - after a lot of fiddling, i, pretty pleased with my result ( see seperate thread ), still im not 100% sure if those maths are correct or just happen to work under the tested conditions. Im not realy good at maths, so a lot of it is guesswork ( especialy when arc-functions are involved ). Currently im using a speed of 75,5 for my calculations - using half G.
At 1 Capaticy, the shot force is around 4000 - divided by 39,5 thats 101,2... ill give this a try together with 1g and see what happens.

MarvinMan

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Re: Need info on plasma-projectiles
« Reply #3 on: December 07, 2016, 08:03:23 pm »
My original combat bot has the full ballistics calculations implemented on its turret, if you want to look at that to see what sort of numbers work.

Lately, I've found that using something like 1/(range*altitude) to set the angle of cannons is a good enough approximation for ACL use.

For longer ranges, you can boost the projectile velocity of cannons by accelerating them with a piston as they fire. A rotary solution may work too, especially for a higher rate of fire, but I expect the aim will be poor and inconsistent.

tob.s

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Re: Need info on plasma-projectiles
« Reply #4 on: December 08, 2016, 01:23:06 pm »
im currently not thinking to much about combat efficency but to figure out ballistics once and for all, atm im using plasma as its much easier to handle ( exact speed, infinite reloads, doesnt blow up your bot if accidentialy triggered ) and its high range shows even the smallest inaccuracys, but once my gun is working, it should be able to fire and hit with anything ( rockets / hypercannons/pistons ) . Basicly all u need would be to adjust the projectiles speed