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[GreatWyrmGold]

Or throw them.

[Urist Da Vinci]

See pre-minecart knockback research here:
http://www.bay12forums.com/smf/index.php?topic=107575.0

I found while investigating knockback in 0.34.07 (just before the minecart release) that crossbows appear to launch bolts at constant momentum (i.e. the shoot force is the F and the delta-t is constant in the impulse "F*delta-t" for you engineers). It appeared that heavy and light bolts were imparting the same momentum on impact, measured in terms of knockback distance, but that light bolts just travelled faster (up until the shoot maxvel)(i.e. constant m*delta-v).

The knockback motion has been altered to use parabolic paths and skidding since, so I wouldn't use the same test methods.

Considering that dropped socks from above do too much damage (potentially lethal!), perhaps the bolts are being launched at the correct force and speed, but the damage calc for all projectiles is bugged?

[GreatWyrmGold]

That would make sense.

[Pirate Bob]

See pre-minecart knockback research here:
http://www.bay12forums.com/smf/index.php?topic=107575.0

I found while investigating knockback in 0.34.07 (just before the minecart release) that crossbows appear to launch bolts at constant momentum (i.e. the shoot force is the F and the delta-t is constant in the impulse "F*delta-t" for you engineers). It appeared that heavy and light bolts were imparting the same momentum on impact, measured in terms of knockback distance, but that light bolts just travelled faster (up until the shoot maxvel)(i.e. constant m*delta-v).

The knockback motion has been altered to use parabolic paths and skidding since, so I wouldn't use the same test methods.

Considering that dropped socks from above do too much damage (potentially lethal!), perhaps the bolts are being launched at the correct force and speed, but the damage calc for all projectiles is bugged?

Hmm...crossbows applying a constant momentum is actually very surprising.  They apply a fixed force over a fixed distance (the length of the crossbow's draw).  Therefore they *should* fire bolts with a constant kinentic energy regardless of mass.  This assumes a massless bowstring and no energy transferred into bow motion, but it seems very unlikely that Toady would include those kind of details.  Also note that it doesn't actually matter if the force applied is constant over the whole distance - the work/energy is the integral of force over distance, and will be contant so long as the applied force doesn't depend on bolt material (which would be quite illogical).

I am not saying it's not correct that DF crossbows impart bolts with constant momentum, regardless of mass.  I am saying that, in the real world, a crossbow will impart constant kinetic energy, neglecting bowstring mass and any motion of the bow itself.  Dwarf Fortress may or may not follow real world physics here.

[NCommander]

I'm vaguely curious if dual-wielding shields increases the chases of successfully blocking them. I once had an adventurer who was pretty much unkillable with legendary shield user + misc object user. If you could post your macros/report scripts, I would be interested in running the test.

[vadia]

See pre-minecart knockback research here:
http://www.bay12forums.com/smf/index.php?topic=107575.0

I found while investigating knockback in 0.34.07 (just before the minecart release) that crossbows appear to launch bolts at constant momentum (i.e. the shoot force is the F and the delta-t is constant in the impulse "F*delta-t" for you engineers). It appeared that heavy and light bolts were imparting the same momentum on impact, measured in terms of knockback distance, but that light bolts just travelled faster (up until the shoot maxvel)(i.e. constant m*delta-v).

The knockback motion has been altered to use parabolic paths and skidding since, so I wouldn't use the same test methods.

Considering that dropped socks from above do too much damage (potentially lethal!), perhaps the bolts are being launched at the correct force and speed, but the damage calc for all projectiles is bugged?

Hmm...crossbows applying a constant momentum is actually very surprising.  They apply a fixed force over a fixed distance (the length of the crossbow's draw).  Therefore they *should* fire bolts with a constant kinentic energy regardless of mass.  This assumes a massless bowstring and no energy transferred into bow motion, but it seems very unlikely that Toady would include those kind of details.  Also note that it doesn't actually matter if the force applied is constant over the whole distance - the work/energy is the integral of force over distance, and will be contant so long as the applied force doesn't depend on bolt material (which would be quite illogical).

I am not saying it's not correct that DF crossbows impart bolts with constant momentum, regardless of mass.  I am saying that, in the real world, a crossbow will impart constant kinetic energy, neglecting bowstring mass and any motion of the bow itself.  Dwarf Fortress may or may not follow real world physics here.

Excluding air resistance, of course.

[thiosk]

Hi everyone. Someone linked me to look at this study and I, having nothing better to do, typesetted it in LaTeX. Then someone suggested me to show this to the author, so here it is!.

(I also did the last one by OP) I like your style, keep it up!

Hahaha!  Journal should be !!SCIENCE!!

[Zivilin]

I'm vaguely curious if dual-wielding shields increases the chases of successfully blocking them. I once had an adventurer who was pretty much unkillable with legendary shield user + misc object user. If you could post your macros/report scripts, I would be interested in running the test.

It would be good if You could compare the results of having a single shield and weapon (the usual setup) with dual-wielding shields. Pirate Bob has already shared his scripts and macros on DFFD:

The scripts and macros I use are posted on DFFD.

I think You'll have to add the code for extracting "block" (hit blocked by shield) and "bat" (hit batted away by weapon) information yourself, since I don't think Pirate Bob did any tests with shields.

[Owlbread]

One advantage that wooden bolts have over other bolts is the fact that if one sets fire to them and shoots someone, they will cause the affected area to melt, causing heavy bleeding beyond the obvious organ damage and torn skin. I have only managed to do this though by being a magma man and picking up bolts, thereby setting them on fire and shooting them at a naked elf very quickly. They do not, however, cause the corpse to ignite, nor the clothing that the corpse was wearing.

At least, that's what my research showed originally. I've just tried that again and it seems that burning bolts cannot be fired. Well, if the bolt was on fire, that was what would happen. I just tried by throwing the burning bolts but again, I was unsuccessful. I think it has to stick in the wound for it to cause the area around it to melt.

[Zivilin]

One advantage that wooden bolts have over other bolts is the fact that if one sets fire to them and shoots someone, they will cause the affected area to melt, causing heavy bleeding beyond the obvious organ damage and torn skin. I have only managed to do this though by being a magma man and picking up bolts, thereby setting them on fire and shooting them at a naked elf very quickly. They do not, however, cause the corpse to ignite, nor the clothing that the corpse was wearing.

At least, that's what my research showed originally. I've just tried that again and it seems that burning bolts cannot be fired. Well, if the bolt was on fire, that was what would happen. I just tried by throwing the burning bolts but again, I was unsuccessful. I think it has to stick in the wound for it to cause the area around it to melt.

I do not have any data on fire bolt damage... however, the probability of a bolt lodging seems to depend on Bolt/Armor material:

Percentage of bolts lodged

Spoiler (click to show/hide)

It is apparent that there are three 'levels' of lodging probability:

• under 50% lodging - occurs for most cases when bolt material is "better" than armor material
• under 20% lodging - occurs for most cases when bolt material is equal to or "worse" than armor material, as well as in the case of wood, bone and copper bolts used against no armor or leather armor
• 0-2% lodging - occurs when wood, bone or copper bolts are used against metal armor

Lodging does not seem to solely depend on the shear yield parameter, since fake bone has a shear yield of 115'000 compared to silver's 100'000, but bolts made of these materials lodged differently. Perhaps weight has an effect at low (around 100'000) shear yields? Or possibly it is governed by a completely different parameter altogether. Surprisingly, copper lodges just as bad as wood and fake bone, despite being a metal. Its shear yield is lower than bone and silver (70'000), which might work towards this effect.

To return to the point, even firing wooden bolts against unarmored targets grants You a 20% chance of lodging at most (and almost no chance against armored opponents). Thus, if lodging is a requirement for a wooden fire bolt to cause fire-based damage, then their usefulness is seriously limited.

[Urist Da Vinci]

One advantage that wooden bolts have over other bolts is the fact that if one sets fire to them and shoots someone, they will cause the affected area to melt, causing heavy bleeding beyond the obvious organ damage and torn skin. I have only managed to do this though by being a magma man and picking up bolts, thereby setting them on fire and shooting them at a naked elf very quickly. They do not, however, cause the corpse to ignite, nor the clothing that the corpse was wearing.

At least, that's what my research showed originally. I've just tried that again and it seems that burning bolts cannot be fired. Well, if the bolt was on fire, that was what would happen. I just tried by throwing the burning bolts but again, I was unsuccessful. I think it has to stick in the wound for it to cause the area around it to melt.

I do not have any data on fire bolt damage...
...
To return to the point, even firing wooden bolts against unarmored targets grants You a 20% chance of lodging at most (and almost no chance against armored opponents). Thus, if lodging is a requirement for a wooden fire bolt to cause fire-based damage, then their usefulness is seriously limited.

I tested flaming arrows on elephants in the arena by creating a Fire Man with an iron bow and 100 mangrove (wood) arrows. I dropped the arrow stack and would only walk back to it to pick up 5 arrows at a time, lest they all burn up before being shot. Elephants tend to survive longer under arrow fire, so I found the following:

- Regular arrow hits appear to ignore the flaming state of the arrow.
- Lodged arrow hits will transfer temperature and flaming status to and from the arrow and victim creature.
- If you ignite the victim creature prior to its death, the corpse will be on fire and burn away.

I'd suggest that some sort of minecart shotgun full of unstacked wooden bolts/arrows, which are set on fire during the launch sequence, would be a devastating antipersonnel weapon.

[GreatWyrmGold]

How would you set them on fire? Send them through a bunch of pastured fire men?
...I want to make some sort of fire-cat now.

[Urist Da Vinci]

How would you set them on fire? Send them through a bunch of pastured fire men?
...I want to make some sort of fire-cat now.

Magma, as always, is the solution:

You put the mangrove bolts [100] into the iron minecart.
You drop the iron minecart.
<<here I rode the cart towards magma and a wall>>
You are caught in a pool of lava!
You are on fire!
You are melting!
The flying ‼mangrove bolts [100]‼ strikes You in the left lower leg, chipping the bone!
A ligament has been torn and a tendon has been torn!
You are on fire!
You are melting!
You slam into an obstacle!

[GreatWyrmGold]

How would you do that in Fortress Mode?

[Urist Da Vinci]

How would you do that in Fortress Mode?

Spill magma on tracks and drive a loaded cart through the 1/7 puddles. Use magma-safe rollers if braking is an issue. After the ignition section, the cart goes downhill 3 z-levels or hits an "exploit linear accelerator" to attain shotgun speed. This isn't a rapid fire weapon by any means, as loading all those wood bolts would take a while.