tanks in PS2 have weak points just like RL tanks. So why don't they deflect projectiles when they aren't a direct hit just like RL?
Because they do. They're entirely immune to every "gun" except the Basilisk/Vulcan. And the only tank weapon that they could deflect would be AP shells, which in this setting I would imagine would be designed to penetrate the enemies vehicle. And the VS don't even use weapons that could be "deflected" in the common sense of the word. While it might be amusing to give MBTs a chance to negate AP Lightnings...
Not quite true. That's a product of tank armor simply stopping those rounds from penetrating at all. If you take a 5.56 rifle today and shoot at a MBT with it, your 5.56 bullets did not fail to penetrate MBT armor due to deflection. Rather they never had enough energy to seriously damage the armor. Small-caliber weaponry simply does squat to heavy armor no matter the angle of impact. It's not a matter of deflection, but simply a failure to penetrate. At least modern saboted projectiles will have a chance to deflect off of heavy armor if the angle is too extreme. It's why many modern tanks still continue to feature things like sloped armor. True it's less effective with modern saboted AP projectiles, but on the other hand PS2 equivalents travel so slowly that deflection is probably a very real possibility (more so I would say than in WWII). Although HEAT and "plasma" are unlikely to be deflected, they can be redirected. Shaped-charge HEAT warheads can explode with the wrong facing, and I'd assume that whatever focused elements there are in a plasma warhead would do the same. Even if that doesn't happen, HEAT and plasma damage would be lessened because they would have to burn through more armor. From a balance perspective however the Magrider would benefit the most from introducing deflection and sloped armor properties, because it's essentially all round. Same for the Prowler's turret. But the Vanguard is quite brick-like, and features less areas where deflection might more reliably occur. That and you'd need all sorts of crazy physics to do real deflection calculations... although a simple modification to our current directional damage model would work: Not quite the same, but at least it's a better approximation of deflection damage reduction than what we have now.
I think trying to simulate a deflection system will just drive everyone batty; and, that's a sufficient reason to leave well enough alone.
While it would certainly be neat to see deflections as they're one of the major reason sloped armor has an advantage, the problem is more likely the information load such deflection would require. You'd need to know the angle at which the round hit versus the angle the armor was at. Right now the way it actually works is your damage is based on the position of the firer and has nothing to do with where your rounds hit. IE if you are directly behind and above a tank and you shoot a missile into its rear, it supposedly calculates as a top armor hit, not a rear armor hit.
