When aiming, draw approximate lines of fire for each turret in range

[olanti-p]

Summary

SUMMARY: Interface "When aiming, draw approximate line of fire for each turret in range"

Purpose of change

Resolves #39557
Aiming UI always draws a single line from player's position to where they aim at.
For some players, it may be confusing: you aim your turrets yet it looks like you would fire from your seat.

Describe the solution

For each turret in range the code calculates a straight line from that turret to target. Due to how cluttered the display may become, the UI by default doesn't draw anything at all, but can be toggled to draw all of these lines.

When aiming a single turret there is no clutter, so line drawing gets automatically enabled (still can be toggled though).

Describe alternatives you've considered

Make this feature work like SNAP_TO_TARGET: it can be disabled/enabled by default via settings menu, but can be temporarily toggled on/off for a single session in aiming UI. I think this is unnecessary since turret lines are more of a visual cue and not "real" lines of fire (these are calculated later, when turrets actually fire). Multiple lines together also look kinda meh due to how the game draws them (no connections, just a trail of dots).

Testing

It compiles, draws and toggles.

Additional context

There may be more to the linked issue than I understand, but nobody corrected me, so I assume that's what it was. Also, gif!

[olanti-p]

Force-pushed to remove already merged commits