[Open Assets] Resource: Respawning objects and bustable FOF

In GFZ1, bustable blocks are set to respawn, but only under the circumstances that, say, weapon panels would respawn. You must be in multiplayer, the cvar respawnitem must be turned on, and they'll respawn after the amount of seconds respawnitemtime is set to.

In ACZ1, bustable blocks are set to respawn, but override the default checks on how to respawn. They will always respawn, even in single player, and always respawn in one second.

Blue crawlas are set to respawn, but again, only under the default circumstances for respawning. Must be in multiplayer, the cvar respawnitem must be turned on, and they'll respawn after the amount of seconds respawnitemtime is set to.

Red crawlas are set to respawn, but override the default checks on how to respawn. They will always respawn, even in single player, and always respawn in one second.

Spikes and wallspikes are set to respawn, but override the default checks on how to respawn. They will always respawn, even in single player, and always respawn in three seconds. They also use a custom function that correctly sets up the spike object based on the options set by the Thing.

FOF respawning is controlled by the level header. To enable, simply include the line Lua.RoverCheck = true in your level header. This will cause Bustable FOFs to respawn using a default function. Basically, this means they will only respawn in multiplayer, when the respawnitem cvar is turned on, and will wait for the value of respawnitemtime before respawning. You can see this in action in GFZ1 in the example script.

You can also specify a custom function to handle respawning. This is used for ACZ1 in the example script. Rawset your function to the global table:
and refer to it in the level header:
This function is called when a bustable block no longer exists - it receives the ffloor_t itself as an argument (note that the example doesn't use this) and should return a tic_t, which is how long to wait before respawning the FOF. If the function returns 0, false, or nil, the FOF will not be respawned.

You can add a hook to respawn a given object type with the function AddObjectTypeRespawn. For safety, you may check that this function actually exists first:
The function takes five arguments:

objecttype: enum (MT_)
The only required argument. The object type to add an MobjRemoved hook for and respawn.

shouldrespawnfunc: boolean function(mo, mo.spawnpoint)
Defaults to RegularShouldRespawn. When an object of objecttype is removed, this function should return whether or not to actually add it to the respawn queue. Note that an object will never be added to the queue without a valid spawnpoint.

timerfunc: tic_t function(mo, mo.spawnpoint)
Defaults to RegularTimer. When an object of objecttype is removed, this function should return the time before respawning, in tics.

spawnfunc: mobj_t function(spawnpoint, objecttype)
Defaults to RegularSpawn. This function is called when it's time to respawn the object. It spawns the object in the correct position, links the object to its spawnpoint and vice-versa, and returns the object. Most objects can use the default spawnfunc.

setupfunc: void function(spawnpoint, mo)
Defaults to RegularSetUp. This function is called after the object is spawned to correctly set things such as its angle and flags. Objects with special properties, such as spikes, will need to use a custom setupfunc.

In the example script, the Blue Crawla uses all the default functions. The Red Crawla uses its own shouldrespawnfunc and timerfunc, while using the default spawnfunc and setupfunc. Spikes and wallspikes use their own shouldrespawnfunc, timerfunc, and setupfunc, but use the default spawnfunc.