bugfix: Prevent manually ejecting rappelling units during combat drops

[Stubbjax]

• Fixes USA Ranger can fall out of Chinook when hitting evacuation before Chinook reached target destination #39

This change prevents rappelling units from being manually ejected during combat drops.

Before

Clicking a passenger's icon in the command bar during a combat drop will eject that unit in the air

DANGEROUS_RAPPEL.mp4

After

Clicking a passenger's icon in the command bar during a combat drop will do nothing

SAFE_RAPPEL.mp4

[bobtista]

Should this be added AFTER confirming door is available?
If I understand correctly, when a door is not available, the status will never get cleared (the loop only clears units in the tracking list), so the unit could get stuck with the flag.

[Stubbjax]

The door cannot be reserved unless getAiFreeToExit returns true. If you follow the chain, you'll find reserveDoorForExit → isSpecificRiderFreeToExit → getAiFreeToExit. It really only needs the status to be set directly before and to be cleared directly after, but I felt it was not as intuitive. Perhaps it is better to do it this way to reduce complexity and the likelihood of unforeseen consequences.

rappeller->setStatus(OBJECT_STATUS_IS_USING_ABILITY);
exitInterface->reserveDoorForExit();
rappeller->clearStatus(OBJECT_STATUS_IS_USING_ABILITY);

It's unexpected that a door is unavailable when rappelling as indicated by DEBUG_CRASH(("rappeller is not free to exit... what?"));.

[bobtista]

Ah, I see what you mean, so the status has to be set before the door reservation, makes sense. This works, although I really enjoy watching the bugged version 😆 . LGTM

[Skyaero42]

This causes a mismatch with retail with the RETAIL_COMPATIBLE_CRC set at (1)

[Skyaero42]

Well done. I tested it and it no longer mismatches.

Summarizing:

• Tested and works as described.
• Tested that the RETAIL_COMPATIBLE_CRC guard is used correctly. Normal build does not mismatch against retail.
• The code looks good.