Can't damage exposed vehicle occupants who are 'enveloped' in a collision box

[Matt Hands]

Affects:

• Crouching commanders in open turrets/superstructure are immune (Greyhound, Wolverine, Achilles, Hellcat, Jackson & Marder).

• Standing commander & the machine gunner in the Marder are mostly blocked by the large col box, so most of their bodies are artificially shielded.

• Bren carrier driver & gunner are wholly/nearly immune to fire (can just shoot top of gunner's head if he's in raised position).

• Half-track drivers are immune from any angle when visor is down & can only be shot from the front when visor is raised.

Exposed player is immune to small arms fire, even if shot by a player standing on top of the turret, or if a grenade is lobbed in.

Reasons for this:

1) Turrets don't have collision static meshes, so crude col box encloses crouching commander & projectile cannot reach him.

2) Even where there is a more detailed col static mesh (Marder & APCs), it is being ignored.

3) Crouching commander's DriverPositions(0) are marked as not exposed. This is done solely to make the correct cannon firing animation play, as an exposed position currently means the shoot 'open' firing anim plays, which would snap the commander up to a standing pose. It makes them invulnerable to all damage.

4) Half-track drivers are marked as not exposed when the visor is down, to stop them being shot from the front, although this makes them invulnerable to all damage.

[Matt Hands]

Fixed, for all but Marder, with new functionality implemented in commit 32b347a.

Meshes modified so collision boxes no longer envelop crouched commander. All commander positions now made bExposed. New RaisedPositionIndexd functionality is used instead of bExposed to determine whether to player open or closed firing animation.

Left issue open for Marder, as that is the hull collision box enveloping the commander, so I want to take a look at how that might differ from open turrets.

[Colin Basnett]

Note that the new collision boxes affect commanders trying to exit out of the turret. They'll often get "stuck" (momentarily) inside the turret and will have to actually jump out. Please verify that the exit positions for the affected vehicles are sound.

[Matt Hands]

Fix for another bug resolves Marder issue. Will adjust exit positions so commander lands probably on rear part of turret (counterweight).

[Matt Hands]

Commit 8df9553 fixes the DH bullet half of the problem where vehicle's collision static meshes are ignored when tracing hits on vehicle occupants. Does not fix the similar problems caused by pre-launch trace, which will be committed separately.

Traces are called on the Instigator (the firing player pawn) & all traces use the collision settings of the actor they are called on. Instigator's collision settings are now temporarily set to bUseCollisionStaticMesh. Again, this is only for the DHBullet half of the problem. Instigator is reset to its default bUseCollisionStaticMesh setting as soon as the traces are done, so it's only for a split second. And that is harmless anyway, because if we set a player pawn to bUseCollisionStaticMesh, all that means is it has more complex collision detection with vehicles, i.e. the player's feet would follow the hull's shape more closely when standing on the vehicle, rather than simply standing on the crude collision box.

[Matt Hands]

Commit c438a0b fixes the remaining pre-launch trace (PLT) half of the problem where vehicle's collision static meshes are ignored when tracing hits on vehicle occupants. Also temporarily makes the Instigator pawn use vehicle collision static meshes in its traces. PLT functionality is moved into new PreLaunchTrace() function, so SpawnProjectile() is shorter & easier to read.

These changes mean the Marder collision boxes no longer need modification, as both bullet collision and PLT now use the vehicle's collision static mesh, so the commander and machine gunner can now be shot.

My remaining problems are no.4 above, where half-track drivers are immune with the visor down, plus I still need to alter the commander's exit positions for open turrets.

[Matt Hands]

Remaining issue no. 4 (half-track drivers immune to damage from all angles when visor closed) is fixed in commit b6c8f8d.

Just need to alter the commander's exit positions for open turrets.

[Matt Hands]

Commit 976f8b9 resolves the last remaining issue, by modifying commander exit positions from open turrets, so that commanders don't exit into the 'hole' in the middle of the modified open turret collision. All now exit onto the front, bulky part of the turret, near the mantlet, to the commander's side.