This is mainly to allow retroactive addition to existing virtual functions without breaking existing content.
The MeansOfDeath fix for Actor.Die would not be possible without such handling.
Due to how function calls get resolved by the code generator there were some incorrect flags on the self pointer which triggered an assert and caused incorrect code generation.
Fortunately this was a mostly contained special case for which a workaround was possible.
The case with forward declared class used as a parent must be handled explicitly
actor MyWeapon : Weapon { Weapon.AmmoType "MyBaseAmmo" }
actor MyAmmo : MyBaseAmmo { }
actor MyBaseAmmo : Ammo { }
This data is game critical and may only be altered by code that knows what is allowed and what not. It must never be altered by any user code ever.
However, since the SkyViewpoint actors need to set up some relations between themselves and the default sky portals the previously purely internal 'internal' flag has been exported as a new keyword.
This was done mainly to reduce the amount of occurences of the word FTexture but it immediately helped detect two small and mostly harmless bugs that were found due to the stricter type checks.
Due to how the VM handles default parameters, these must always be identical to the parent to prevent undefined behavior.
So now, if such parameters are encountered, the compiler will either abort (for script version >= 3.3) or print a warning (for older versions.)
Any defaults being specified for older versions will be ignored, though, and the defaults of the parent function be copied to the override.
Due to the special nature of this expression the code generator got stuck in 'address' mode and passed the address of the variable instead of its value.
The order of processing is different here so when the property gets parsed there are no states to delete.
To fix this the property just flags the class and lets the ZScript state compiler deal with this as needed.
The following ill-formed ZScript code might crash targets with sizeof(int) != sizeof(void*) like 64-bit Intel
class test { void func() { if (true) ( return; ) } }
Note that this is merely a hotfix. Properly handling this to allow universal use of state scopes will require more work in cases where a scoped state is being accessed through a non-self pointer.
This is to ensure that the Class pointer can be set right on creation. ZDoom had always depended on handling this lazily which poses some problems for the VM.
So now there is a variadic Create<classtype> function taking care of that, but to ensure that it gets used, direct access to the new operator has been blocked.
This also neccessitated making DArgs a regular object because they get created before the type system is up. Since the few uses of DArgs are easily controllable this wasn't a big issue.
- did a bit of optimization on the bots' decision making whether to pick up a health item or not.
Let's use inline checkers in PType instead of constantly having to do clumsy IsKindOf checks etc. Once complete this also means that the types can be taken out of the class hierarchy, freeing up some common names.
Fixed bunch of compilation errors:
cannot pass non-trivial object of type 'FString' to variadic method; expected type from format string was 'char *' [-Wnon-pod-varargs]
Fixed linker erorr:
g_doomedmap.cpp.o: In function `InitActorNumsFromMapinfo()':
src/g_doomedmap.cpp: undefined reference to `PClass::FindActor(FName)'
Combining these two groups of data has been the cause of many hard to detect errors because it allowed liberal casting between types that are used for completely different things.
Having these two types related can cause problems with detection in the compiler because for some parts they need quite different handling.
Common handling for the fields has been moved into PSymbolTable but overall redundancy was quite minor as both types share surprisingly little functionality.
- fixed: IsVisibleToPlayer and optimized it a bit more.
- moved SourceLumpName to PClass, so that it can also be used for non-actors (there's a lot of non-Actor classes already.)
- separated the serializer for PClassPointer from PPointer. Even though not doable, a pointer to a class type is something entirely different than a class pointer with a restriction so each should handle its own case.
- added a few access functions for FActorInfo variables.
With PClassActor now empty the class descriptors can finally be converted back to static data outside the class hierarchy, like they were before the scripting merge, and untangle the game data from VM internals.
For these fields maps have no advantage. Linearly searching a small array with up to 10 entries is nearly always faster than generating a hash for finding the entry in the map.
- some optimization of access to OwnedStates in old DECORATE.
- consolidate all places that print a state name into a subfunction.
- allocate states from the ClassDataAllocator memory arena. States do not need to be freed separately from the rest of the static class data.
This reinstates the old FActorInfo as part of the meta data a class can have so that the class descriptor itself can be freed from any data not directly relevant for managing the class's type information.
This is an incredibly costly way to do a debug check as it infests the entire VM design from top to bottom. These tags are basically useless for anything else but validating object pointers being passed to native functions (i.e. mismatches between definition and declaration) and that simply does not justify a feature that costs execution time in non-debug builds and added memory overhead everywhere.
Note that this commit does not remove the tags, it only discontinues their use.
- decided to ditch the widget system I had started to lay out. As it turns out that would make things far more complicated and slower than they need to be.
This makes VMValue a real POD type with no hacky overloads and eliminates a lot of destructor code in all places that call a VM function. Due to the way this had to be handled, none of these destructors could be skipped because any value could have been a string.
This required some minor changes in functions that passed a temporary FString into the VM to ensure that the temporary object lives long enough to be handled. The code generator had already been changed to deal with this in a previous commit.
This is easily offset by the code savings and reduced maintenance needs elsewhere.
Note that the Strife status bar does not draw the health bars yet. I tried to replace the hacky custom texture with a single fill operation but had to find out that all the coordinate mangling for the status bar is being done deep in the video code. This needs to be fixed before this can be made to work.
Currently this is not usable in mods because they cannot initialize custom status bars yet.
It used the expression's value type, but needs to use the variable's, which can be different when the assignment is synthesized from a builtin function.
- keep string registers which are being used as function parameters allocated until after the function call returns. This is for allowing to pass strings by reference which would avoid some costly constructor/destructor loops in the call instruction.
src/gl/scene/gl_clipper.h:150:23: warning: comparison of integers of different signs: 'int' and 'unsigned int' [-Wsign-compare]
src/gl/dynlights/gl_aabbtree.cpp:137:24: warning: using integer absolute value function 'abs' when argument is of floating point type [-Wabsolute-value]
src/gl/dynlights/gl_aabbtree.cpp:137:34: warning: using integer absolute value function 'abs' when argument is of floating point type [-Wabsolute-value]
src/gl/dynlights/gl_aabbtree.cpp:137:44: warning: using integer absolute value function 'abs' when argument is of floating point type [-Wabsolute-value]
src/gl/dynlights/gl_aabbtree.cpp:139:6: warning: using integer absolute value function 'abs' when argument is of floating point type [-Wabsolute-value]
src/gl/dynlights/gl_aabbtree.cpp:139:30: warning: using integer absolute value function 'abs' when argument is of floating point type [-Wabsolute-value]
src/gl/dynlights/gl_aabbtree.cpp:139:54: warning: using integer absolute value function 'abs' when argument is of floating point type [-Wabsolute-value]
src/gl/dynlights/gl_aabbtree.cpp:142:6: warning: using integer absolute value function 'abs' when argument is of floating point type [-Wabsolute-value]
src/gl/dynlights/gl_aabbtree.cpp:143:3: warning: using integer absolute value function 'abs' when argument is of floating point type [-Wabsolute-value]
src/gl/dynlights/gl_aabbtree.cpp:144:3: warning: using integer absolute value function 'abs' when argument is of floating point type [-Wabsolute-value]
src/gl/dynlights/gl_aabbtree.cpp:167:6: warning: using integer absolute value function 'abs' when argument is of floating point type [-Wabsolute-value]
src/gl/dynlights/gl_shadowmap.cpp:163:31: warning: '&&' within '||' [-Wlogical-op-parentheses]
src/p_saveg.cpp:367:16: warning: comparison of integers of different signs: 'unsigned int' and 'int' [-Wsign-compare]
src/p_saveg.cpp:402:60: warning: comparison of integers of different signs: 'int' and 'unsigned int' [-Wsign-compare]
src/p_setup.cpp:1553:39: warning: format specifies type 'ptrdiff_t' (aka 'long') but the argument has type 'int' [-Wformat]
src/scripting/zscript/zcc_compile.cpp:293:74: warning: field 'AST' will be initialized after field 'mVersion' [-Wreorder]
src/swrenderer/drawers/r_thread.cpp:113:21: warning: comparison of integers of different signs: 'int' and 'size_t' (aka 'unsigned long') [-Wsign-compare]
- allow treatment as one-character string constants as character constants. This became necessary because name constants already use single quotes and are much harder to repurpose due to a higher degree of ambiguity.
- fixed: protected methods in structs were not usable.
This is only the parsing part, the arrays are not yet getting evaluated.
This required quite a hacky workaround because the gramma couldn't be made to accept the rule. The scanner will check if a 'static' token is immediately followed by a 'const' token and will combine both to a new 'staticconst' token that does not create conflicts with other rules.
This method was chosen because it avoids adding variable declarations to the global namespace which would have required a lot more work while polluting the grammar.
This way the global variables can be handled by a small bit of special coding in the struct generator.
Both files can now be included independently without causing problems.
This also required moving some inline functions into separate files and splitting off the GC definitions from dobject.h to ensure that r_defs does not need to pull in any part of the object hierarchy.
- block creation of actors with the 'new' instruction. Unlike the above these cannot be made abstract because without ConstructNative they cannot be serialized.
The code for constants was not optimal because the first operand of the instructions cannot be constant. This was solved by swapping it with the second choice which will always be non-constant.
The code for local variables did not allocate a new destination register and would overwrite the first parameter's variable.
It now uses a dedicated opcode instead of piggybacking on OP_CALL and it passes data that is closer to the VM. Symbols should be avoided at this level.
It also will skip the scope instruction if the code generator detects that both calling function and the self pointer type have the same scope, this assumes that subclasses cannot flip between UI and Play.
They are not needed for OP_NEW_K which can evaluate the class relations at compile time and for OP_NEW the calling function can also be checked at compile time, passing only the scope value itself.
Note that this completely disables the newly added keywords 'play' and 'ui' for unversioned code to allow using them as identifiers as I have found at least one mod that uses a variable named 'play' that would have been rendered broken otherwise.
This also disables many ZScript only keywords for other parsing jobs.
- made the self pointer of const functions readonly.
This seems to work fine. Both calling a non-const function and trying to assign a value to a member fail with an error message.
Clearscope is a dangerous context and should be limited to the minimum extent possible and preferably be blocked in user code.
This may still need some work on const functions but better have it in now.
This is to block modification of the planes directly. For future-proofness with renderer changes everything that alters these values should go through he function interface.
src/scripting/zscript/zcc_compile.cpp: warning: comparison of integers of different signs: 'int' and 'unsigned long' [-Wsign-compare]
src/p_acs.cpp: warning: format specifies type 'char *' but the argument has type 'PClass *' [-Wformat]
- use an enum type for ItemFlags, just like it was done for actor flags. Since the flag word is almost full it may soon be necessary to add a second one and then this kind of security check may become necessary.
- made CameraHeight a modifiable actor property - it was readonly before.
- allow accessing the type constants from ZScript, this required quite a bit of explicit coding because the type system has no capabilities to search for basic types by name.
This will store class meta properties in a separate memory block so that it won't have to muck around with PClass - which made the implementation from the scripting branch relatively useless because extending the data wasn't particularly easy and also not well implemented. This can now be handled just like the defaults.
- do not resolve the backdrop texture to a texture ID at load time. This will allow custom menu classes to use this info differently.
- added a new ZSDF userstring property to dialog pages to give mods more means for customization.
- allow overriding the conversation menu class both globally through MAPINFO and per conversation in ZSDF.
Like the symbols and the VM functions this is data that is static from startup until shutdown and has no need to be subjected to garbage collection. All things combined this reduces the amount of GC-sensitive objects at startup from 9600 to 600.
Making this an object had little to no advantage, except being able to remove the deleter code. Now, with some of the class data already being allocated in a memory arena so that freeing it is easier, this can also be used for the drop item lists which makes it unnecessary to subject them to the GC. This also merges the memory arenas for VM functions and flat pointers because both get deleted at the same time so they can share the same one.
Now all actors have the same metaclass and therefore it will always be the same size which will finally allow some needed changes to the type system which couldn't be done because it was occasionally necessary to replace tentatively created classes due to size mismatches.
There's simply never enough of them and they are used far too infrequently to justify the hassle of tagging along two TMaps per class.
For what they provide, single global lists that handle all player classes at once are fully sufficient.
The goal is to get rid of PClassPlayerPawn and PClassInventory so that the old assumption that all actor class descriptors have the same size can be restored
This is important to remove some code that seriously blocks optimization of the type table because that can only be done if types do not need to be replaced.
Symbols are very easy to manage once they are in a symbol table and there's lots of them so this reduces the amount of work the GC needs to do quite considerably.
After cleaning out compile-time-only symbols there will still be more than 2000 left, one for each function and one for each member variable of a class or struct.
This means more than 2000 object that won't need to tracked constantly by the garbage collector.
Note that loose fields which do occur during code generation will be GC'd just as before.
- removed all pointer declarations to types from the symbols. All types must be placed into the type table which means that they can be considered static.
As it stood, just compiling the internal ZScript code created more than 9000 DObjects, none of which really need to be subjected to garbage collection, aside from allowing lazy deallocation.
This puts an incredible drag on the garbage collector which often needs several minutes to finish processing before actual deletion can start.
The VM functions with roughly 1800 of these objects were by far the easiest to refactor so they are now. They also use a memory arena now which significantly reduces their memory footprint.
- use a memory arena to store flat pointers so that the messed up cleanup can be avoided by deallocating this in bulk.
- added a new SO opcode to the VM to execute a write barrier. This is necessary for all objects that are not linked into one global table, i.e. everything except thinkers and class types.
- always use the cheaper LOS opcode for reading pointers to classes and defaults because these cannot be destroyed during normal operation.
- removed the pointless validation from String.Mid. If the values are read as unsigned the internal validation of FString::Mid will automatically ensure proper results.
- removed some code repetition by inherit all variable types which reference a PField for a variable offset from a base class so that PField replacements can be done with one set of code.
error: use of undeclared identifier 'op'
error: no matching function for call to 'ListEnd'
error: no matching function for call to 'ListGetInt'
error: no matching function for call to 'ListGetDouble'
...
This isn't done for register based variables so for consistency it should not be done for stack based variables, too.
This difference in handling made it impossible to check the target of a hitscan attack if it was destroyed by getting damaged.
This function will truncate everything that is larger than LONG_MAX or smaller than LONG_MIN to fit into a long variable, but longs are 32 bit on Windows and 64 bit elsewhere, so to ensure consistency and the ability to parse larger values better use strtoll which does not truncate 32 bit values.
The general rule is as follows: A class name as a string will always be looked up fully, even if the class name gets shadows by another variable because strings are not identifiers.
It is only class names as identifiers that must obey the rule that if it is not known yet or hidden by something else that it may not be found to ensure that the older variable does not take over the name if it gets reused.
If a later module reused an existing name for a different class or struct type, this new name would completely shadow the old one, even in the base files.
Changed it so that each compilation unit (i.e. each ZScript and DECORATE lump) get their own symbol table and can only see the symbol tables that got defined in lower numbered resource files so that later definitions do not pollute the available list of symbols when running the compiler backend and code generator - which happens after everything has been parsed.
Another effect of this is that a mod that reuses the name of an internal global constant will only see its own constant, again reducing the risk of potential errors in case the internal definitions add some new values.
Global constants are still discouraged from being used because what this does not and can not handle is the case that a mod defines a global constant with the same name as a class variable. In such a case the class variable will always take precedence for code inside that class.
Note that the internal struct String had to be renamed for this because the stricter checks did not let the type String pass on the left side of a '.' anymore.
- made PEnum inherit from PInt and not from PNamedType.
The old inheritance broke nearly every check for integer compatibility in the compiler, so this hopefully leads to a working enum implementation.
- load internal shaders only from file 0. This does not contain aborts, like most of the other checks,but it will now refuse to load any core shader file from anything but gzdoom.pk3.
- fixed the return type checks in CallStateChain. These made some bogus assumptions about what return prototypes to support and would have skipped any multi-return function whose first argument was actually usable.
This should for now conclude actor class scriptification. The remaining ten classes with the exception of MorphedMonster are all too essential or too closely tied to engine feature so they should remain native.
* completely scriptified DehackedPickup and FakeInventory.
* scriptified all remaining virtual functions of Inventory, so that its inheritance is now 100% script-side.
* scriptified CallTryPickup and most of the code called by that.
- fixed: Passing local variables by reference did not work in the VM.
- ensure that actor defaults contain a valid virtual table and class pointer so that they can actually use virtual and class-dependent method functions. This is needed for retrieving script variables from them.
- added some helpers to set scripted member variables through the native property parser.
Unfortunately some classes, e.g. PowerMorph, MorphProjectile and the powerup contain some that cannot be handled through the 'property' definition on the script side so they need to be done from the native side.
- improved the class pointer to string cast to print the actual type it describes and not the class pointer's own type.
- fixed: The 'is' operator created non-working code when checking the inheritance of a class pointer, it only worked for objects.
This revealed an interesting bug: When the berserk fadout formula was changed in 2005 the result was essentially broken, resulting in values around 7000 - it only worked by happenstance because the lower 8 bits of the resulting values just happened to work to some degree and never overflowed. But the resulting fade was far too weak and a slightly different handling of the color composition code for the VM made it break down entirely.
This restores the pre-2005 formula but weakened intensity which now comes a lot closer to how it is supposed to look.
- support transient object member variables for information that does not need to be put in a savegame.
- fixed: special initialization of objects needs to pass the proper defaults along, otherwise the parent classes will use their own, inappropriate one.
gl/data/gl_setup.cpp:430:11: warning: comparison of integers of different signs: 'int' and 'unsigned int' [-Wsign-compare]
gl/data/gl_setup.cpp:527:19: warning: comparison of integers of different signs: 'int' and 'unsigned int' [-Wsign-compare]
gl/data/gl_setup.cpp:542:19: warning: comparison of integers of different signs: 'int' and 'unsigned int' [-Wsign-compare]
nodebuild.cpp:1056:63: warning: format specifies type 'ptrdiff_t' (aka 'long') but the argument has type 'int' [-Wformat]
p_glnodes.cpp:379:50: warning: comparison of integers of different signs: 'int' and 'unsigned int' [-Wsign-compare]
p_saveg.cpp:381:18: warning: comparison of integers of different signs: 'int' and 'unsigned int' [-Wsign-compare]
p_scroll.cpp:532:11: warning: comparison of integers of different signs: 'int' and 'unsigned int' [-Wsign-compare]
p_setup.cpp:2304:43: warning: format specifies type 'int' but the argument has type 'unsigned long' [-Wformat]
p_setup.cpp:2302:12: warning: comparison of integers of different signs: 'int' and 'unsigned long' [-Wsign-compare]
scripting/codegeneration/codegen.cpp:8488:20: warning: comparison of integers of different signs: 'int' and 'size_t' (aka 'unsigned long') [-Wsign-compare]
scripting/codegeneration/codegen.cpp:8606:15: warning: comparison of integers of different signs: 'int' and 'size_t' (aka 'unsigned long') [-Wsign-compare]
No need to maintain these clunky meta class for one single property. The overhead the mere existence of this class creates is far more than 100 spawned ammo items would cost.
There is no need to serialize AAmmo::DropAmount, this value has no meaning on an already spawned item.
There are a few which require explicit native construction or destruction that need to be exported to the VM, e.g. FCheckPosition.
The VM cannot handle this directly, it needs two special functions to be attached to handle such elements.
- 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.
