Markus Armbruster
a269cdd7e9
Before Empire 2, nukes could be delivered only with bomb (special mission 'n', airburst only) and launch (targeting sectors or satellites only). Empire 2 made nukes available for any kind of bombing, and for any missile strike on sectors or ships. This included interdiction and support missions. Nuclear-tipped anti-sats and bomb mission n were removed. Unfortunately, this was done in a messy way, which led to inconsistencies and bugs. The problem is that ordinary damage affects just the target, while nuke damage affects an area. Code dealing with plane damage was designed for the former. Instead of rewriting it to cope with area damage cleanly, nuke damage got shoehorned into pln_damage(), the function to compute conventional plane damage, as a side effect: computing damage blasted sectors in the area. If the plane carried a nuke, pln_damage() returned zero (conventional) damage. Without further logic, this simply bypassed the code to apply damage to the target. This worked out okay when the target already got damaged correctly by the side effect. However, some targets are immune to the side effect: when interdicting a move or explore command, the commodities being moved are not in any sector. For other targets, damage has effects other than damaging the target: offensive and defensive support don't apply the (conventional) damage to the target sector. Instead, they turn it into a combat bonus. Without further logic, nuclear damage doesn't contribute to that. To make all that work, pln_damage() returned the nuclear damage for ground zero as well. Because a plane does either conventional or nuclear damage, one of them is always zero. Most callers simply ignored the nuclear damage, and applied only the conventional damage. Bug: land units and ships failed to retreat when pin-bombed or missiled with a nuke. That's because they received zero conventional damage. The mission code flies planes and missiles and tallies their damage. This mission damage included nuclear damage at ground zero (except for missiles sometimes, see below), to make support and commodity interdiction work. Unfortunately, this broke other things. Bug: when bombers interdicted ships or land units, nukes first damaged the ships or land units by the side effect, then again through mission damage. Interdicting missiles had a special case to avoid this. Bug: when interdicting move, explore or transport, nukes first damaged the sector by the side effect, then again through mission damage's collateral damage. There may well be more bugs hiding in this mess. The mess is not worth fixing. While the idea of interdicting and supporting with nukes sounds kind of cool, I believe it's pretty irrelevant in actual play. Instead, go back to a variation of the original rules: nukes can be delivered only through bomb mission 's' and launch at sectors. Make arm reject marine missiles in addition to satellites, ABMs and SAMs, and clear the mission. Make mission reject planes armed with nukes. Oops when they show up in mission_pln_equip() anyway. Make pln_equip() allow planes with nukes only for missions 's' and 't'. Clean up pln_damage() to just compute damage, without side effect. Change strat_bomb() and launch_missile() to detonate nukes. Simplify the other callers. Parameter mission of msl_launch_mindam() is now unused, remove it. Missiles exploding on launch no longer set off their nukes. That was pretty ridiculous anyway.
121 lines
4.1 KiB
Perl
121 lines
4.1 KiB
Perl
.TH Concept Hitchance
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.NA Hitchance "The chance of a projectile hitting its target"
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.LV Expert
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This page describes the chance of a mine, torpedo, ship anti-missile
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defense, missile, or plane hitting its target.
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.nf
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Sea Mine hitchance
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The chance of a ship hitting a mine at sea is (mines/(mines+20)). (For
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example, with 20 mines, the chance of hitting one is 20/40 = 50%) The
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damage is dependent upon the size of the ship and the spot that the
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mine hits. (see \*Qinfo Damage\*U).
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Land Mine Hitchance
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The chance of a land unit hitting a land mine is mines/(mines+35).
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(For example, with 20 mines, the chance of hitting one is 20/55 =
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36%). See \*Qinfo Damage\*U to find out how much damage things take
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from land mines. Note that the chance of land units hitting land
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mines is divided by 3 if the land units are accompanied by engineers.
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When moving commodities (civs, mil, shells, etc) or transporting
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planes, the chance is also dependent upon the weight being moved.
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First the above chance is checked, and then a chance equal to (weight
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/ 100) is checked.
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Torpedo hitchance
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The chance of a torpedo hitting its target is equal to:
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hitchance = 0.9/(range + 1)
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where "range" is the range to the target. If the visibility of the
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ship firing is less than 6, then (5 - visibility) * 0.03 is added to
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the hitchance.
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Thus, the base chance of a sub hitting its target (before visibility
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modification) is:
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Range Chance
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0 90%
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1 45%
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2 30%
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3 22.5%
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4 18%
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5 15%
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Ships anti-missile defense
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If a ship has "anti-missile" defense capabiilty, then it will
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intercept any marine missiles launched at ships within 1 sector of the
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ship. Only missiles belonging to a country you are "At War" with will
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be intercepted. Only ships which are at least 60% efficient will be
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able to use their anti-missile defenses. The chance of the ship
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hitting the incoming missile it equal to:
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hitchance = gun * eff * tfact * 4.5 - (missile "def" value)
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where
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gun = the number of guns the ship is allowed to carry
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eff = the efficiency of the shiip
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tfact = tech / (tech + 200)
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where
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tech is the tech level that the ship was built at
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Plane and missile hitchance
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If the target is
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a sector, then the hitchance is 100%. Otherwise, the following
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procedure is used to calculate hitchance.
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The formula for a plane or missile hitting its target depends on the
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type of the target (ship, plane, land unit) and the "hardtarget" value
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of the target (which represents how hard that target is to hit).
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Ship:
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vis = the visibility of the ship (from 'show ship stats').
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For a sub, we set vis = visibility * 4.
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If the ship is at sea, then:
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hardtarget = (eff of ship) * (20 + speed/2 - vis)
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otherwise:
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hardtarget = (eff of ship) * (20 - vis)
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The hardtarget of a fleet is the hardtarget if the "easiest" target in
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the fleet.
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Land unit:
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hardtarget = (efficiency) * (10 + (sector defense) * 2 + speed/2 - vis)
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The hardtarget of an army is the hardtarget of the "easiest" target in
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the army.
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Plane:
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If the plane is in the air (satellite, icbm), then
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hardtarget = the "def" value of the plane.
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otherwise if the plane is on the ground:
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hardtarget = 0
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Once we have calculated the "hardtarget" value of the target, then the
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chance of a plane or missile hitting its target is equal to:
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hitchance = acc - hardtarget
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where
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acc = (efficiency) * (1 - 0.1 * tfact) * (1 - placc/100)
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where
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tfact = (pltech - mintech)/(pltech - mintech/2)
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where
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pltech = tech level of plane
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mintech = min tech level required to build plane
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and
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placc = plane accuracy
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and if the target is a ship and the plane is an ASW plane, then
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placc = placc - 20
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and if the target is a ship and the plane does not have tactical capability
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placc = placc + 35
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Lastly we smooth out the bottom end of the hitchance curve. If
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hitchance is less than 20, then it is "belled up" using the following
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curve:
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hitchance = 5 + 300 / (40 - hitchance).
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On the other hand, you can just find out the hitchance by pinbombing
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or launching a missile--the hitchance is always printed! :-)
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.fi
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.SA "fire, launch, bomb, torpedo, Attacking, Damage, Interception, Combat"
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