Realistic Missile Weapons

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jayhova
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Realistic Missile Weapons

Post by jayhova »

I have been playing a lot of Bannerlord recently and missile weapons in that game move on ballistic curves. I was curious as to what someone might think about creating something similar for DFU. I was briefly considering that you could also vary the damage by distance. However, I looked at the numbers and the damage drop from an arrow slowing is only about 2% at 50 yards. By the time an arrow has gone 100 yards, it is moving faster than it was when it left the bow.
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l3lessed
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Re: Realistic Missile Weapons

Post by l3lessed »

I can look into this for my combat mod ambidexterity module.

It shouldn't be too hard, just figuring out the math function to calculate the proper arcs, and then replace the current arrow mechanism with it.
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jayhova
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Re: Realistic Missile Weapons

Post by jayhova »

l3lessed wrote: Thu Aug 04, 2022 5:42 pm I can look into this for my combat mod ambidexterity module.

It shouldn't be too hard, just figuring out the math function to calculate the proper arcs, and then replace the current arrow mechanism with it.
https://www.archerytalk.com/threads/arr ... r.4524721/

The above forum thread talks quite a bit about it. Gravity in DFU is one of the variables. IMHO the best solution might be to have missiles fall at the same rate as the PC/MOBs. At that point, you could simply get the flight speed of the arrow right. It would be nice if better bows imparted more energy into the arrow increasing its flight speed. Here is data on flight speeds of arrows fired from various bows. The best speed on a english longbow is somewhere around 175FPS this might be slightly lower with heavier war arrows (designed to penetrate armor and not just deerskin). There is some info out there on arrows used in ancient times on Wikipedia etc.
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jayhova
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Re: Realistic Missile Weapons

Post by jayhova »

Arrows do not describe a perfect parabola. Because they have fins they resist the force of gravity pulling down on them. Were they bullets from a sling, you would cast them at something a bit less than 45 degrees, They would strike their target at something less than the speed they left the sling. Arrows on the other hand gain speed as they decend.
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jayhova
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Re: Realistic Missile Weapons

Post by jayhova »

This PDF describes heights at apogee for arrows fired to their maximum range. It looks like the height gained for distance traveled is about 1/4. That is to say if your max range is about 1000ft (333.3 yrds) Apogee for your arrow would be at about 250ft (83.3 yrds). The issue is that the further your target is the slower the speed toward the target will be. I am not speaking of arrow speed but rather horizontal travel speed.

Let's say your target is 50 yards away. You have a bow that fires at 150 FPS. At that distance, the arrow takes 1 second to reach the target. The drop on the arrow is only a couple of feet. The difference between the flight speed of the arrow leaving the bow and the speed to the target is negligible. However, by the time your target is at maximum range, your aim is at 45°. This means that half of the speed of the arrow is going into lift. This means that the horizontal distance being traversed per second is also half. The arrow will start to accelerate after apogee however a good portion of this acceleration will be offset by the arrow slowing somewhat during its assent. Now let's say our target is at 250 yards. Rather than taking 5 seconds for the arrow to reach the target, the arrow will take closer to 10 seconds.
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jayhova
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Re: Realistic Missile Weapons

Post by jayhova »

ImageI was curious about the terminal velocity of an arrow (the speed at which an arrow fired straight down would no longer accelerate due to drag). This Google site sent me down a huge rabbit hole. Turns out that 200 F/s is where the drag of air and the pull of gravity meet.

As you can see the flight of an arrow is not symmetrical. Apogee is not halfway through flight as it would be for a purely ballistic object such as a cannonball.
Remember always 'What would Julian Do?'.

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