EVE Corporation - Page 1290

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When they start aggressing, the 'yellow box' will turn red (but it will still be pretty subtle). However, as the hits start coming in, a new 'hit icon' will flash around the bracket, one for each hit from that pilot. The opacity of the icon will be determined by the damage of the hit. If they are shooting at you with a weapon that has short cycle time but each shot doesn't deal much damage, you will see many faint hit icons, very rapidly. If they're shooting you with something that really, really hurts, the hit icons will be very strong when they flash but you might not see them as often if the cycle time of their modules is rather long.

We have not yet come up with an exact calculation method for the opacity of the hit icon but we are working from this right now:

opacity = hitHP / (ourShieldHP + ourArmorHP) * magic

That is; the opacity of the hit icon will indicate the impact to YOUR ship. If the hit takes a big chunk of your hitpoints (HP), you will see the attacker's hit icon flash strongly even if it was a pretty lousy shot for their equipment.
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