* Can't simply use the previous fade_out color as the default, because of an edge-case with legacy usage. The refactor would disallow setting the fadout to black.
This is a follow-up to PR #2942. Given that the short-circuiting is now explicitly skipped for node trees containing the special argument, it should no longer be necessary to flush the conditional branch of the sexp tree. (The .cache field is already skipped for special-arg nodes.)
The sexp tree is still explicitly flushed for `every-time` and `every-time-argument`.
It takes a number as a maximum number of arguments that can be evaluated in a single call, but otherwise behaves very similarly to `any-of`; alternatively, if the number is 1, it's like an `in-sequence` that also skips arguments that don't satisfy the condition instead of just invalid ones.
If a message string contained a word that was too long, on its own, for the available screen real estate, the function wouldn't split the string at all. The new behavior is to split the string even if the split location is suboptimal, since it's better to have as much of the message visible as possible.
Quoting from the code:
```
// only update the line break if:
// a) we don't have a line break yet;
// b) we're still within the required real estate
// (basically we want the latest line break that doesn't go off the edge of the screen,
// but if the *first* line break is off the end of the screen, we want that)
```
* Fix underline length calculation in message scrollback
* Use SCP_string for message source (which allows ships with long display names to work without crashing) and message text
* Upgrade assorted functions to work with SCP_string
This makes the red-alert SEXP execute properly in multiplayer.
Note, this is just the SEXP. Multi-knowledgeable people will need to evaluate `red_alert_start_mission` and `red_alert_maybe_move_to_next_mission` to make sure those functions will work properly in multiplayer.
Collision groups as previously coded were unusable due to Lua 5.1's lack of support for bitwise operators. This fixes that deficiency in two ways:
1) Objects now have the functions `addToCollisionGroup` and `removeFromCollisionGroup`
2) An `evaluateNumericSEXP` function has been added for returning SEXP results as numbers (so that the bitwise SEXP operators can be used)
The previous system was kind of hacky and made things a bit inflexible.
This improves that system quite a bit and also adds unit tests for the
hook variable functionality.
These sexps work just like for-counter, supplying arguments for when-argument. They will list all ships that are present in the mission and are of a certain class or type.
This is specifically for OPF_SHIP. Currently if you specify a LuaSEXP with OPF_SHIP, it only works for ships that are present in the mission when the SEXP is called. This is my attempt at a LuaSEXP parameter variant that will return a valid ship name regardless of the ship status. It required a bit of finagling the existing API.
In most cases you have one group to/from which you are adding or removing several ships, but the existing sexps are designed for one ship and many groups. This adds new sexps designed for one group and many ships.
Goober5000