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.
- 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.
- 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 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()'
- 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.
- 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.
- 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.
- added state usage specifiers to Actor and Inventory. The states in these classes must be set to full access so that any existing mod can link to them.
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.
- fixed creation of direct function invocations on a state line. In order to receive the implicit arguments this needs to be wrapped into a compound statement so that the local variable getter works.
The proper setup for such classes was only done in CreateDerivedClass, but not in FindClassTentative itself. This extends CreateDerivedClass to allow it to create a class without fully initializing it.
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.
- made 'DamageMultiply' an actor property and moved the initialization of ConversationRoot to the property handler for the compiler to get this stuff out of the type classes.
- consolidate default initialization into one function which performs all the required setup. The original implementation did this when adding the fields but that cannot work because at that time no defaults have been created yet.
- fixed: When deriving a class the child class's defaults also must initialize the copied parent fields with special initialization. This part was completely missing.
- removed DECORATE code for parsing native classes because it's no longer needed.
- Since the number of small allocations here is extremely high this will help a lot to prevent fragmentation and since most nodes are collected up front and this is done when no large resources are being loaded it won't cause heap spikes.
let Emit methods delete FxExpression arrays when they are done.
- For some reason the deletion process does not work 100%, there are always some nodes left behind and so far I haven't found them. This ensures that these arrays do not live any longer than needed.
* use the function build list instead of the function to pass the info. The function is permanent so not the best place for compile-time info.
* pass along the current state index which is needed to calculate the target state.
