Interesting tidbit: The damage calculation in P_MinotaurSlam had been incorrect for the Heretic version since the friendly Hexen Dark Servant was added, but nobody ever noticed in 14 years...
Needless to say, this is simply too volatile and would require constant active maintenance, not to mention a huge amount of work up front to get going.
It also hid a nasty problem with the Destroy method. Due to the way the garbage collector works, Destroy cannot be exposed to scripts as-is. It may be called from scripts but it may not be overridden from scripts because the garbage collector can call this function after all data needed for calling a scripted override has already been destroyed because if that data is also being collected there is no guarantee that proper order of destruction is observed. So for now Destroy is just a normal native method to scripted classes
- scriptified all Effect functions of Fastprojectile's children
- implemented access to class meta data.
- added a VM instruction to retrieve the class metadata, to eliminate the overhead of the function call that would otherwise be needed.
- made GetClass() a builtin so that it can use the new instruction
Important note about this commit: Scriptifying CFlameMissile::Effect revealed a problem with the virtual function interface: In order to work, this needs to be explicitly enabled for each single native class that may be used as a base for a scripted class. Needless to say, this will end up way too much work, as there are over 100 native classes, excluding those which will be scriptified. But in order to fix the problem this partially broken state needs to be committed first.
- renamed APowerMorph::Player to avoid accidental confusion with AActor::player, which in scripting is the same due to case insensitvity.
- renamed save key for above variable.
This prevented any kind of error check on them.
Unfortunately, due to backwards compatibility needs, on DECORATE the missing class may not be fatal so a workaround had to be added to clear those bogus pointers later if they are discovered to be broken.
For ZScript, though, this will result in a compile error, which was the intention behind this change.
- implemented multiple-return-value assignment. Due to some grammar conflicts the originally intended Lua-inspired syntax of 'a, b = Function()' could not be done, so it's '[a, b] = Function()'
- changed Dehacked weapon function lookup to check the symbol table instead of directly referencing the VM functions. Once scriptified these pointers will no longer be available.
- removed all special ATAGs from the VM. While well intentioned any pointer tagged with them is basically unusable because it'd trigger asserts all over the place.
- scriptified A_Punch for testing pass-by-reference parameters and stack variables.
- instead add a list of SpecialInits to VMScriptFunction so this can be done transparently when setting up and popping the stack frame. The only drawback is that this requires permanent allocation of stack objects for the entire lifetime of a function but this is a relatively small tradeoff for significantly reduced maintenance work throughout.
- removed most #include "vm.h", because nearly all files already pull this in through dobject.h.
- added a DActorIterator class.
- fixed: It was not possible to have functions of the same name in two different classes because the name they were searched for was not qualified by the class. Changed so that the class name is included now, but to avoid renaming several hundreds of functions all at once, if the search fails, it will repeat with 'Actor' as class name.
This commit contains preparations for scriptifying Hexen's Dragon, but that doesn't work yet so it's not included.
- added an 'exact' parameter to FThinkerIterator's Next function. This is mainly for scripting which allows to do a lot more checks natively when running the iterator while looking for one specific class.
- fixed emission of the self pointer in FxVMFunctionCall. I did not realize that the self expression only sets up a register for the value, not pushing it onto the stack.
- split FinishActor into several functions. While DECORATE can, ZSCRIPT cannot do all this in one go.
- split the state finalization into several class-specific virtual functions.
* everything related to scripting is now placed in a subdirectory 'scripting', which itself is separated into DECORATE, ZSCRIPT, the VM and code generation.
* a few items have been moved to different headers so that the DECORATE parser definitions can mostly be kept local. The only exception at the moment is the flags interface on which 3 source files depend.
This uses the same property and flag tables as DECORATE with a few changes:
* it sets the parse mode to strict, so that several DECORATE warnings are now errors.
* trying to change a deprecated flag will print a warning.
* setting of editor numbers, spawn and conversation ID id not possible. Use MAPINFO to do this.
* all subclass flags must use the qualified name now (e.g. +ALWAYSPICKUP will print an error.)
* the scriptable Damage property is not yet implemented. This will require a special case with a differently named property in the processing function because in the AST it is no longer possible to distinguish between a damage value and a constant damage function.
After testing with a savegame on ZDCMP2 which is probably the largest map in existence, timing both methods resulted in a speed difference of less than 40 ms (70 vs 110 ms for reading all sectory, linedefs, sidedefs and objects).
This compares to an overall restoration time, including reloading the level, precaching all textures and setting everything up, of approx. 1.2 s, meaning an increase of 3% of the entire reloading time.
That's simply not worth all the negative side effects that may happen with a method that highly depends on proper code construction.
On the other hand, using random access means that a savegame version change is only needed now when the semantics of a field change, but not if some get added or deleted.
- do not I_Error out in the serializer unless caused by a programming error.
It is better to let the serializer finish, collect all the errors and I_Error out when the game is known to be in a stable enough state to allow unwinding.