I decided to check out an old problem that was fixed by Khoros way back.
The basics:
Erratic Manuevers (EM) make your ship harder to be hit by zig-zagging rapidly, which makes sense for atmospheric aircraft and probably starships too. This violent movement also makes your own weapons less accurate as one might expect.
This is represented in SFC2 defensively as a +4 ECM bonus to the EM user and offensively as a +4 ECM penalty. Interestingly, ECCM can be used to mitigate or negate this offensive penalty. Likewise, enemy ships can use ECCM to eliminate the protection generated by Erratics. It might not be the most logical system but evasive manuevers are simply using the currency of electronic warfare to adjust hit percentages.
This is certainly a complex thing to code! An initial problem was that the game applied the current target's attack shift to phaser point defense (PD), which would often decrease PD accuracy. This was not appropriate because incoming missiles (and fighters, shuttles, and plasma) were able to inherit a third party's attack shift. The proper attack shift should be determined by comparing the individual missile's ECM with the defending ship's ECCM. Since SFC's missiles (and plasma) have zero ECM by design, an attack shift can't normally occur. On the other hand, fighters have 2 points of ECM (unfortunately invisible in the sensor panel), so the defending ship would need just 2 ECCM to have unhindered phaser PD against them.
However, the game needed to account for the self-imposed penalty created by EM (and nebulae). So a ship would need to be running 4 ECCM with Erratics to negate the penalty applied to its phaser PD fire. It would take 9 ECCM to completely burn through a nebula (or 13 ECCM to negate EM + Nebula penalties) which is impossible. This was fixed by Khoros by making the attack shift calculation for PD more sophisticated so that it wouldn't be improperly affected by the current target's ECM and would account for EM penalties...a remarkable feat!
However, somewhere along the line this fix was removed/disabled. In 2.5.4.10 you can use Erratics without suffering any phaser PD woes. (Your tractors will be disabled naturally).
I tested this in single-player mode. I used a K-D7 against a Z-POL with small (Type-I) missiles. I never used more than 3 Ph-2s to shoot down 3 missiles. According to the Range 0 Ph-2 chart I should do insufficient damage to destroy a small missile 33% of the time while penalized by an attack shift of 2 (i.e. 4 ECM vs 0 ECCM). I targeted the Z-POL, missiles, and nothing at all with the same results. Phaser fire is immune to attack shifts against missiles but Disruptor fire is not.
I later used one point of ECM while Erratic (5 total ECM) and targeted a missile. An attack shift of 3 was displayed. This means the EM penalty was doubled, at least cosmetically, as 4ECM*2 + 1ECM = 9ECM which yields a shift of 3. However, my Ph-2's ignored this penalty.
I then decided to test EAW 2.036...unfortunately, the same problem occurs there. I wonder if the porting of the OP-style instantly-on Erratics into 2.033 wiped out the properly functioning electronic warfare environment found in 2.013.
Since this isn't a CTD problem, I have no expectation that anything will be done about this. This is just FYI.
EDIT: I loaded up 2.013. EM wasn't taken into account in phaser PD. It must be found in a later patch (2.033) or I am incorrect in asserting that this was ever fixed. Perhaps it was fixed only in multiplayer (where I recall testing it back then).
Topic: 2.5.4.10: Erratic Manuevers don't affect phaser point defense hit% (Read 2388 times)