The player will be respawned, their lives decreased, and the board
cleared. The UI doesn't update, and the sudden snap to a freshly reset
board is quite jarring. The state transition to GameOver stops the game,
but there isn't anything else running in that state so it just looks
frozen.
Basically, there's a ton left to do, but technically I have handled
player ship destruction!
The spacebar fires the gun, bullets are spawned on top of the ship with
a velocity that sends them forward (relative to the ship).
I still need a despawn mechanism, and a fire rate control. To despawn
things, I'm already planning a `Lifetime` component. For rate of fire,
an additional component will be created and attached to the player ship.
The ship in Asteroids isn't expected to spin up while holding a steering
direction, but that's exactly what I just made it do.
Fix that problem by assigning, not accumulating, the angular velocity
for the ship.
The physics sim bits (that aren't Rapier2d) are now in their own
submodule. I've included the `Wrapping` marker component because it
doesn't really have anywhere else to live, and it's kinda sorta related
to the physics. It controls the motion of objects... that's physics. :p
There are name collisions between Rapier2d's `Velocity` and my own, but
that's a problem for later. I've used more specific type paths where
necessary to maintain the previous behavior.
The `physics::Position` component can go away completely. It's just an
extra copy of some of the built-in `Transform` data. I'm pretty sure it
only exists because I didn't realize I could rely on directly
manipulating the transform when I started this project.
