The major issue here is that if you calculate damage as the proportion of surface area of the beam on each critical component, then you're introducing a crap ton of calculations on the server. I'll explain:
You're now having to...
(perform a frustum cast, which is much more expensive than a raycast)
x (total number of lasers being fired simultaneously during a given frame)
x (some work to determine which hitboxes are hit or are close to being hit by those lasers)
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= to get the final work required every single frame.
As a second matter, have you ever shot at a roaming Firestarter and not had your fire register? That's because the server can't know exactly what your commands to steer your mech and spin your torso are until
at least half your ping's time into the future after you actually entered those inputs. That's a pretty wide window where the server's simulation of the game can differ from yours, and those two simulations are effectively out of phase by a little bit all the time.
Take a look here for a little demo on how this actually looks:
To get a good idea, enter Lag = 100, prediction and reconciliation both on, server updates 30 times per second (MWO servers are probably honestly a bit lower than this).
http://www.gabrielga...m/fpm_live.html
PGI often talks about HSR (Host State Rewind) as an aid to improving hit detection. What it does is rebuild the current game simulation in the past according to exactly how it believes you the player should have viewed the world anytime your client reports that you've fired at and hit your target. If it can confirm your "head shot" according to your supposed view, it takes it at face value and updates the server simulation to include this "head shot" within the original simulation, even if originally the server saw your opponent duck marginally behind a wall in time. Your opponent might have even escaped from your sights on their screen, but the server accepts your version of events as good enough.
The amount of work required to produce your surface-area laser would wreck HSR, preventing that system from correcting hits from lasers.
Lasers currently either hit or do not hit. If they do hit, the range at which the hit occurred is made available by very the nature of how raycasts work. They're very simple to do (consider that machine-guns create raycasts for every bullet, or think of some other FPS with rifles or whatever). I imagine one laser as you described might be more intense on the server hardware than 24 FS9-As in a game today.
TL;DR: Server workload for calculating damage not feasible. Game would feel unresponsive.
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Before the laser-lock mechanic got scrapped, I had imagined a visual effect like this to show whether your lasers were firing with enhanced range or not. I like the idea behind the visual, as long as damage isn't part of the suggestion.
Technically speaking, the cheapest way to make a 3D laser would be to render it as a coloured pyramid, with one vertex on the weapon's firing point and a triangle face drawn on whatever is being hit. It also couldn't shine through crevices between components like a flashlight except on very high-end rigs, and you couldn't expect all players to see the same thing.
TL;DR #2: I still like the visual effect! I think it would have been a great way to show when your lasers were firing at optimal range in the current PTS #3.