Bay 12 Games Forum

Please login or register.

Login with username, password and session length
Advanced search  

Author Topic: Ballistas: Minimum Effective Range: 17 - 25 tiles & Arrow Properties  (Read 2362 times)

Schmaven

  • Bay Watcher
  • Abiding
    • View Profile

In order for a operator to not flee in terror while sending ballista bolts into the faces of your enemies, there needs to be a minimum of 20 25 tiles between the dwarf in the center of the ballista, and the enemy. 

Method:
An undead dwarf corpse was put in a 1x1 room with 3 fortifications on 1 side.  Outside the fortifications, a raising 2x5 bridge was constructed to shield the undead from view.  A ballista was then constructed, faced toward the undead, and ordered to be ready to fire.  Once the ballista operator was aboard the ballista, the lever was pulled to lower the bridge - unrestricting the view of the undead.  Various distances were tested. 

With 19 tiles between the center of the ballista and the undead, the operator flees.
With 20 tiles between the center of the ballista and the undead, the operator happily awaits the command to fire. 

Spoiler: Test Range (click to show/hide)

No ballista arrows were fired because due to a shortage of wood in this fort, only 1 ballista arrow exists.

Edit: Distance correction + Title change
« Last Edit: October 25, 2020, 05:45:49 pm by Schmaven »
Logged

Uthimienure

  • Bay Watcher
  • O frabjous day!!
    • View Profile
Re: Ballistas' Minimum Effective Range
« Reply #1 on: October 17, 2020, 07:30:28 pm »

Nice test.  Does any type of operator flee, i.e., does the operator's bravery or military skill (or etc.) matter?
Logged
FPS in Gravearmor (850+ dwarves) is 3-6 (v0.47.05 lives on).
"I've never really had issues with the old DF interface (I mean, I loved even 'umkh'!)" ... brewer bob
As we say in France: "ah, l'amour toujours l'amour"... François D.

Schmaven

  • Bay Watcher
  • Abiding
    • View Profile
25 Tiles
« Reply #2 on: October 17, 2020, 10:53:28 pm »

Good question.  I'm 99% sure it's only the dwarves' observer skills determine how close the enemy can get before spooking them.  All dwarves Any dwarf that can see will get spooked at a certain distance.

Further testing lead to a range of 17 to 25 tiles of space needed depending on whether the dwarf is just a dabbling observer or a legendary +5 observer. 

The first test was entirely done with 1 dwarf with the following stats (I'm just guessing which ones might have an effect here):

Gap Required: 20 tiles
Discipline: Dabbling (0)
Siege Operator: Talented (6)
Concentration: Dabbling (0)
Observer: Adequate: (2)

In the second round of tests, the ballista was moved 1 tile closer to the zombie, such that 19 tiles of space (including 1 tile of ballista and 1 tile of fortification) separate the operator; the military commander was ordered to prepare the ballista to fire; and the lever was pulled.  The commander immediately fled.  The ballista was then moved back 1 tile such that 20 tiles of space separate them.  This caused the commander to also flee.  Ultimately, the ballista had to be relocated such that 25 tiles separate are between the center of the ballista and the undead in order for the commander to hold strong.  The commander's stats are:

Gap Required: 25 tiles
Discipline: Legendary +5 (20)
Siege Operator: No experience (-)
Concentration: Talented (6)
Observer: Legendary +5 (20)

I'm thinking it's the observer skill at work.  Discipline (unless offset by observer) skill does not seem to have any effect.  It also appears that siege operator skill has no effect on the spook range.  Interestingly, the change from 0 observer skill to 2 observer skill increased the distance required by 3.  Lower level skill gains here seem to have greater effects. 

A stonemason with the following skill levels was also tested to find the other end of the minimum fright distance:

Gap Required: 17 tiles
Discipline: No experience (-)
Siege Operator: No experience (-)
Concentration: No experience (-)
Observer: Dabbling (0)

The stonemason was able to man the ballista with a gap of only 17 tiles between their operator position and the undead. 

Spoiler: Ranges Visible Here (click to show/hide)
In the image above, the crosshairs vertically line up with the center point of the ballista when the commander or the stonemason fled.  The up stairs align with the center of the ballista where they would sit happily awaiting to fire.  And the upward pointing triangles indicate the width of the ballista to make counting tiles of space easier. 

Setting up ballistas with a 25 tile gap is just about a whole vertical screen for me:
Spoiler: In Practice (click to show/hide)

The commander committed suicide by running into a platinum minecart grinder after concluding these fear tests... 
Spoiler: Ground Commander (click to show/hide)

I'm not really doing this with a good test fort, so I'm going to end my experiments here.  I just wanted to set up an effective ballista battery, and needed to know how much of a dead zone to leave in front.  Eventually, I'll post the effectiveness of steel tipped ballista bolts against various targets, but that's going to take a while to get set up.

Further science could be done to figure out:
  • At what observer skill levels does the distance required change?
  • Better control over varying dwarf skills to explore that 1% chance some other skill affects the distance

Edit: Formatting
« Last Edit: October 18, 2020, 04:18:31 am by Schmaven »
Logged

Bumber

  • Bay Watcher
  • REMOVE KOBOLD
    • View Profile
Re: Ballistas' Minimum Effective Range
« Reply #3 on: October 17, 2020, 11:32:38 pm »

Nice test.  Does any type of operator flee, i.e., does the operator's bravery or military skill (or etc.) matter?

A blind operator doesn't flee. ;)
Logged
Reading his name would trigger it. Thinking of him would trigger it. No other circumstances would trigger it- it was strictly related to the concept of Bill Clinton entering the conscious mind.

THE xTROLL FUR SOCKx RUSE WAS A........... DISTACTION        the carp HAVE the wagon

A wizard has turned you into a wagon. This was inevitable (Y/y)?

Eric Blank

  • Bay Watcher
  • *Remain calm*
    • View Profile
Re: Ballistas' Minimum Effective Range: 17 - 25 tiles
« Reply #4 on: October 21, 2020, 04:45:41 pm »

We must pluck out their eyes!
Logged
I make Spellcrafts!
I have no idea where anything is. I have no idea what anything does. This is not merely a madhouse designed by a madman, but a madhouse designed by many madmen, each with an intense hatred for the previous madman's unique flavour of madness.

MorsDux

  • Bay Watcher
  • If you only have a hammer, all problems seem nails
    • View Profile
Re: Ballistas' Minimum Effective Range
« Reply #5 on: October 23, 2020, 11:35:02 am »

Nice test.  Does any type of operator flee, i.e., does the operator's bravery or military skill (or etc.) matter?

A blind operator doesn't flee. ;)

Do you guys know of a controlled way to .......never mind, thats way too dark for me..
Logged

Schmaven

  • Bay Watcher
  • Abiding
    • View Profile
Re: Ballistas' Minimum Effective Range: 17 - 25 tiles
« Reply #6 on: October 24, 2020, 05:01:54 am »

We must pluck out their eyes!

I don't know much about adventure mode, but that seems like the best way to blind but not kill a bunch of dwarves. 

But if you're "lucky" you could capture a FB that shoots a blinding spittle in fort mode, then arrange for some encounters.
Logged

delphonso

  • Bay Watcher
  • menaces with spikes of pine
    • View Profile
Re: Ballistas' Minimum Effective Range: 17 - 25 tiles
« Reply #7 on: October 24, 2020, 10:15:06 am »

Since they're civilians, they're likely to flee when they see a threat, even if battle-hardened warriors (since there would be no path to engage). Might be worth a suggestion that soldiers can man ballistas + catapults so their discipline can come into play.

Schmaven

  • Bay Watcher
  • Abiding
    • View Profile
Ballista Damage
« Reply #8 on: October 25, 2020, 05:21:10 pm »

As far as ballista bolt specifics go, here's some comparative information on their weights:

featherwood log: 5
spore tree log: 30
Steel ballista arrowhead: 78

Steel ballista arrowhead on spore tree log: 235
Steel ballista arrowhead on featherwood tree log: 235

Copper ballista arrowhead: 89
Steel ballista arrowhead: 78
Tunnel tube log: 25

Copper ballista arrowhead on tunnel tube log: 267
Steel ballista arrowhead on tunnel tube log: 235

Steel ballista arrows vs targets:
Spoiler: Unarmored Dwarf (click to show/hide)
Spoiler: Giant (click to show/hide)
Spoiler: Same Giant (click to show/hide)

The giant bled to death shortly after the last hit.

Edit: More steel ballista arrow combat reports:
« Last Edit: October 26, 2020, 07:53:54 pm by Schmaven »
Logged

Schmaven

  • Bay Watcher
  • Abiding
    • View Profile
Conclusion: Ballistas are Very Effective
« Reply #9 on: November 01, 2020, 10:06:25 am »

After further testing, I'm now convinced that ballistas are highly effective at killing medium sized creatures typical of those found in a goblin siege. 

Here are some stitched together combat reports from a recent goblin siege:
In the first volley, a single steel ballista arrow completely disabled 3 trolls who were all in a row, then continued on to kill a goblin.  A copper ballista arrow 1-shot killed a troll as well.  Not bad at all.

Spoiler: Ballistas vs Goblins (click to show/hide)
Spoiler: Ballistas vs Trolls (click to show/hide)
Spoiler: Ballistas vs Beak Dog (click to show/hide)

Occasionally, a goblin would block part the ballista arrow, but being large projectiles, each arrow almost always hits each creature 4 times.  In those instances where the ballista arrow was blocked, the goblins were still horribly maimed.  So it seems they can only partially block ballista shots. 

Once the operators are trained up to "(4) Skilled", their shots are pretty much completely straight down the range.  Definitely by "(6) Talented".  And with a proper training range, it's pretty easy to level them up.

« Last Edit: November 01, 2020, 11:02:37 am by Schmaven »
Logged