It is utterly pointless to require every function that wants to make a VM call to allocate a new stack first. The allocation overhead doubles the time to set up the call.
With one stack, previously allocated memory can be reused. The only important thing is, if this ever gets used in a multithreaded environment to have the stack being declared as thread_local, although for ZDoom this is of no consequence.
- eliminated all cases where native code was calling other native code through the VM interface. After scriptifying the game code, only 5 places were left which were quickly eliminated. This was mostly to ensure that the native VM function parameters do not need to be propagated further than absolutely necessary.
- added call wrappers and script hooks for all relevant virtuals in AInventory.
- made GetSpeedFactor and GetNoTeleportFreeze entirely scripted because they are too trivial - also do them iteratively, just like HandlePickup, because it's just a better way to do this stuff.
- moved health items to their own file.
- scriptified ScoreItem and MapRevealer whose entire functionality was a small TryPickup method.
- fixed: bit fields in global variables were not correctly written.
This should conclude the inventory cleanup. It is now possible again to find things in there.
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
- refactored state bitfield members into a flag word because the address of a bitfield cannot be taken, making such variables inaccessible to scripts.
- actually use PNativeStruct for representing native structs defined in a script.
- 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.
This could cause problems with functions that take states as parameters but use them to set them internally instead of passing them through the A_Jump interface back to the caller, like A_Chase or A_LookEx.
This required some quite significant refactoring because the entire state resolution logic had been baked into the compiler which turned out to be a major maintenance problem.
Fixed this by adding a new builtin type 'statelabel'. This is an opaque identifier representing a state, with the actual data either directly encoded into the number for single label state or an index into a state information table.
The state resolution is now the task of the called function as it should always have remained. Note, that this required giving back the 'action' qualifier to most state jumping functions.
- refactored most A_Jump checkers to a two stage setup with a pure checker that returns a boolean and a scripted A_Jump wrapper, for some simpler checks the checker function was entirely omitted and calculated inline in the A_Jump function. It is strongly recommended to use the boolean checkers unless using an inline function invocation in a state as they lead to vastly clearer code and offer more flexibility.
- let Min() and Max() use the OP_MIN and OP_MAX opcodes. Although these were present, these function were implemented using some grossly inefficient branching tests.
- the DECORATE 'state' cast kludge will now actually call ResolveState because a state label is not a state and needs conversion.
Syntax-wise I chose to make it as strict as possible to reduce the chance of errors: Virtual base functions must be declared with the 'virtual' keyword, and overrides in child classes with the 'override' keyword. This way any mismatch in parameters that otherwise would cause silent failure will outright produce a compile error.
- exported thinker iterator and drop item chain to scripting. Unlike its native counterpart the script-side iterator is wrapped into a DObject to allow proper handling for memory management.
- fixed: The VMFunctionBuilder only distinguished between member and action functions but failed on static ones.
- fixed: FxAssign did not add all needed type casts. Except for purely numeric types it will now wrap the expression in an FxTypeCast. Numeric handling remains unchanged for both performance reasons and not altering semantics for DECORATE.
- exported all internal flags as variables to scripting. They still cannot be used in an actor definition.
- make ATAG_STATE the same as ATAG_GENERIC. Since state pointers exist as actual variables they can take both values which on occasion can trigger some asserts.
- gave PClass a bExported flag, so that scripts cannot see purely internal classes. Especially the types like PInt can cause problems.
Todo: we need readonly references to safely expose the actor defaults. Right now some badly behaving code could overwrite them.
- fixed: FxMinusSign trashed local variables that were used with negation.
- fixed: FxConditional only handled ints and floats, but not pointers and strings.
- fixed: A 'no states in non-actors' error was triggered, even for classes without any states.
This will restrict them to the only classes that may use them: Weapon and CustomInventory.
Note: Should a mod surface which uses them improperly the better solution would be a warning message and NULLing the bogus code pointer instead of leaving them in Inventory.
Ironically this only requires a very minor change in the calling code and an added member for the VMFunction to tell that code how many parameters to pass.
This change will allow to turn the vast majority of action functions into regular members, the only ones that still need to be an action function are the few that actually use the pointers.
* explicitly require passing the owning class when creating it.
* extract self pointer class when adding a variant.
* put the flags on the single variants, we can not fully rule out that they will be 100% identical, if variants ever get allowed.
* 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.
To do the rest, some cleanup is needed first, to untangle the DECORATE parser from the actual code generation so that the low end stuff can actually be reused here instead of having to be redone.
Instead of replacing the original, the second class will get renamed now, using the originating file as an identifier. In the vast majority of cases this should do exactly what is needed: Create an unconflicting second class that can coexist with the original. Unless the class is used by name this should eliminate all problems with this, but so far I haven't seen anything that used them by name.
This is choosing the lesser of two evils. While some mod out there may get broken, the old setup meant that the first class of a given name could not be written out to a savegame because it was not retrievable when loading it back.
The way this was done was a major headache inducer, requiring reconstruction of the function each time the value was changed and in general made actor damage a major hassle.
There was a DECORATE wrapper to mimic the original behavior but this looked quite broken because it completely ignored the different semantics of both damage calculation types.
It also made it impossible to determine if damage was a function or a value.
This accessor has been reverted to what it should be, only returning the constant, which now is -1 for a damage function. I am sorry if this may break the odd mod out but a quick look over some DECORATE-heavy stuff showed that this was never combined in any of them so that accessing 'damage' in DECORATE code depended on an actual damage function.
To get proper damage, a future commit will add a DECORATE function which calls AActor::GetMissileDamage.
- replaced some uses of FRACUNIT with OPAQUE when it was about translucency.
- simplified some overly complicated translucency multiplications in the SBARINFO code.
- Converted P_MovePlayer and all associated variables to floating point because this wasn't working well with a mixture between float and fixed.
Like the angle commit this has just been patched up to compile, the bulk of work is yet to be done.
