- created script exports for all relevant functions with all integral types.
- created script side definitions for the underlying data types.
- added a void pointer type so that the prototype for the pointer array can use a generic type every pointer can be assigned to.
- disabled the Build map loader after finding out that it has been completely broken and nonfunctional for a long time. Since this has no real value it will probably removed entirely in an upcoming commit.
- made ModifyDamage calls iterative instead of recursive. With going through the VM they'd be too costly otherwise.
- small optimization: Detect empty VM functions right when entering the VM and shortcut them. This is to reduce the overhead of virtual placeholders, which in a few cases (e.g. CanCollideWith and ModifyDamage) can be called quite frequently.
If the calling code wants to recycle this it will have to pass a container variable to AActor::UnlinkFromWorld and AActor::LinkToWorld.
This was changed because keeping such data in a global variable is dangerous for a set of functions that can be called from a script.
Note that the scripted versions do not yet support saving of the touching_sectorlist.
Instead of trying to fix Simplify, which seems to be a lost cause, the ring list now gets unraveled into an array which is immune from this type of problem.
This can see some heavy use in iterators where saving several hundreds of function calls can be achieved. In these cases, using a function to do the job will become a significant time waster.
* It will now use #include, just like most other definition formats and can be mixed with regular definitions. However, due to how the Lemon-generated parser works this will not recursively pull in all files, but store them in a list and process them sequentially. Functionally this shouldn't make a difference, because ZScript is mostly order-independent - the only thing where order is important is native classes, but these are completely internal to zdoom.pk3 where proper order is observed.
Note that this only applies if both are in the same block. Just like in C++, it is perfectly legal to have the same variable name in two different nested scopes.
The original implementation just printed a mostly information-free message and then went on as if nothing has happened, making it ridiculously easy to write broken code and release it. Changed it to:
* Any VMAbortException will now terminate the game session and go back to the console.
* It will also print a VM stack trace with all open functions, including source file and line numbers pointing to the problem spots. For this the relevant information had to be added to the VMScriptFunction class.
An interesting effect here was that just throwing the exception object increased the VM's Exec function's stack size from 900 bytes to 70kb, because the compiler allocates a separate local buffer for every single instance of the exception object.
The obvious solution was to put this part into a subfunction so that it won't pollute the Exec function's own stack frame. Interesting side effect of this: Exec's stack requirement went down from 900 bytes to 600 bytes. This is still on the high side but already a lot better.
- fixed PARAM_ACTION_PROLOGUE to assign correct types to the implicit pointers. It gave the actual class to the wrong one, which until now did not matter because all functions were using 'Actor', regardless of actual class association.
- fixed the definition of IceChunk and removed some redundant code here. Since A_FreezeDeathChunks already calls SetState, which in turn calls the state's action function, there is no need to call it again explicitly.
- throw a useful exception when a VM abort occurs, the simple enum was incapable of reporting anything more than the barest minimum, which at least for array index out of bounds errors was insufficient.
The current exception mechanism is still insufficient. It really has to report a proper crash location and print a stack trace to the maximum extent possible. Instead it just prints a message and happily goes on. This is not a good solution.
Although this already helps a lot with the messed up code generated for comparisons it's not really a solution for this - it still needs a proper implementation to generate efficient code.
- fixed: When replacing a tentative class, the pointers in the morph objects were not replaced. Instead of adding more ReplaceClassRef methods I chose to integrate this part into the PointerSubstitution mechanism and delete ReplaceClassRef entirely. The code had some oversights anyway that would have caused problems, now that non-actors can be created.
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.
- 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.
- Changed the glass shards so that they do not have to override FloorBounceMissile. It was the only place where this was virtually overridden and provided little usefulness.
- made 'out' variables work.
- fixed virtual call handling for HandlePickup.
- added a String class to allow attaching methods to the builtin string type. This works by checking if the left side of the member accessor is a string and just replacing the tyoe in this one place, all the rest is automatic.
- merged the FrontBlock searcher for the Bloodscourge into RoughMonsterSearch. This also fixes the bug that the searcher was not initialized properly for the MageBoss.
A few notes:
* this accesses the lines array in sector_t which effectively is a pointer to an array of pointers - a type the parser can not represent. The compiler has no problems with it, so for now it is defined internally.
* array sizes were limited to 65536 entries because the 'bound' instruction only existed as an immediate version with no provisions for larger values. For the static map arrays 65536 is not sufficient so now there are alternative instructions for these cases.
* despite the above, at the moment there is no proper bounds checking for arrays that have no fixed size. To do this, a lot more work is needed. The type system as-is is not prepared for such a scenario.
- fixed: Assignment from a readonly to a read-allowed pointer must be an error.
- made GetDefaultByType a builtin so that it can do proper type assignment to the result, which for a function would be problematic in this case, even if automatic type deduction was implemented. Since this returns the class defaults which are not a real object, the result cannot be subjected to a type cast.
- error out if a type cast of a readonly pointer is attempted.
- fixed: FxBooleanNot could clobber a local variable because it used the source register to manipulate the result.
- fixed issues with the refactoring of the recent commits. This one starts again.
- added builtins for TextureID.
Note about builtins: Currently they are just hacked into the compiler backend. They really should be made part of the respective types to keep matters clean and allow more widespread use of builtins to create more efficient code.
Two reasons for this:
1. if this has to be routed through the VM each recursion will cost 1000 bytes of stack space which simply is not good.
2. having the virtual function only care about the item itself but not the entire inventory chain is a lot less error prone for scripting.
Since the scripting interface needs a separate caller function anyway this seemed like a good time to change it. The same will be done for the other chained inventory handlers as well.
- allow switch/case with names.
- fixed break jump target handling for switch/case. This only worked when the break was in the outermost compound statement, those in inner ones were missed.
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...
- Took the opportunity and fixed the logic for the Skull Rod's rain spawner. The old code which was part of the 3D floor submission was unable to work with portals at all. The new approach no longer tries to hide the dead projectile in the ceiling, it leaves it where it is and changes a few flags, so that its z-position can be used as reference to get the actual ceiling. This works for line portals, but for sector portals still requires some changes to sector_t::NextHighestCeilingAt to work, but at least this can be made to work unlike the old code.
- added names for the player-related translations to A_SetTranslation.
- fixed: Failure to resolve a function argument was checked for, too late.
- made the parameter for A_SetTranslation a name instead of a string, because it is more efficient. We do not need full strings here.
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.
- fixed: FxAssignSelf did not the correct number of registers for vector operations.
- fixed a few asserts in vector2 instructions.
- turned the virtual AActor::HitFloor method into a flag MF7_SMASHABLE. The only use of this function was to kill Hexen's pottery when they hit the floor, and this looks like something that can be exposed to modders less clumsily.
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.
- added new VARF_Transient flag so that the decision whether to serialize a field does not depend solely on its native status. It may actually make a lot of sense to use the auto-serializer for native fields, too, as this would eliminate a lot of maintenance code.
- defined (u)int8/16 as aliases to the byte and short types (Can't we not just get rid of this naming convention already...?)
- exporting the fields of Actor revealed a few name clashes between them and some global types, so Actor.Sector was renamed to CurSector and Actor.Inventory was renamed to Actor.Inv.
- 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.
- fixed flag CVAR access. As it turned out, OP_LBIT is a bit messy to set up properly when accessing integers that may or may not be big endian, so it now uses a shift and bit masking to do its work.
- used the SpawnPlayerMissile call in A_FireBFG to test named arguments.
- fixed: The code generator had no good safeguards for exceeding the maximum amount of registers.
All there was was a handful of pitiful asserts which in production code do nothing at all but generate broken output.
Even worse, the VM was hardwired to at most 255 constants per type per function by storing the constant count in a byte! This has been extended to 65535, but since many instructions only have a byte available for the constant index, a workaround had to be added to do a two-instruction setup if larger indices are needed.
- added new VM instructions to access the constant tables with a variable index.
- refactored VMFunctionBuilder's constant tables so that they are not limited to one entry per value. While this works fine for single values, it makes it impossible to store constant arrays in here.
- implemented method calls from struct instances.
- optimized disassembly of VM call instructions to print the function's name at the end where it is more visible and does not need to be truncated. Also use the printable name for script functions here.
- 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()'
- made APlayerPawn::PlayAttacking(2) virtual script functions so that mods have better control over player animations. Note that these have no native base so they skip the templated interface for managing virtual functions.
- added a new type 'NativeStruct'. This will be used for types that cannot be instantiated, and is also needed to cleanly handle many internal types that only can exist as reference.
- 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.
- gave OP_CONCAT some sane semantics. The way this was defined, by specifying the source operands as a range of registers instead of a pair like everything else made it completely useless for the task at hand.
- changed formatting for floats to %.5f which for normal output in a game makes more sense. For special cases there should be a special formatting function for ints and floats that can do more specialized conversions.
- make the pointer to string cast a bit more useful by using the actual object's type rather than 'Object' which can be a great asset when debugging.
- fixed a few bad asserts.
- fixed code generation for using local variables as array index. This must use a different register for the array element offset because the original register may not be overwritten.
- 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.
- fixed several places in the code generator that did not consider locked registers for local variables: array indices, abs and floating point builtin functions.
- added some debug aids to the bounds opcode. Just triggering an exception here which loses all relevant info is perfectly useless in a debug situation.
- 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.
- preserve a state's source line information for the postprocessing phase so that the checker can output more useful information.
- added missing check for weapon psprites to DPSprite::SetState.
