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.
- 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.
- 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.
- 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 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.
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.
* Revert "Modify CMPJMP to produce more compact code (as far as VC++ is concerned, anyway)"
This reverts commit 6ff973a06b.
This modification did not work and broke the comparisons. Actually this had three problems:
* the asserts checked the wrong instruction
* the mask was not applied to regular comparisons.
* incrementing PC before testing does not work because 'test' references the PC.
- 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.
- removed the bogus optional value from the first A_Jump argument. A quick test with an older ZDoom revealed that this was never working - and implementing it would make things a lot more complicated, especially error checking in the code generator.
- fixed: The check for insufficient parameters to a function call was missing.
- removed mulv_kr and divv_kr instructions. The first are redundant and the second are useless. Maybe remove all other vector/const operations as well? They won't get used by the code generator.
- fixed disassembly of vector multiplication and division instructions.
- fixed: ZCCCompiler did not process array access nodes.
- fixed: Function argument names were not placed in the destination list by the compiler.
- scriptified several trivial functions from p_actionfunctions.cpp.
- disabled the assert in PType::GetRegType. This assert blocks any use to check for types that are incompatible with function parameters.
- pass the default parameter constants to the native functions. At the moment this is not used yet.
- use the function defaults to complete argument lists to script functions.
- fixed all default values that got flagged by the expression evaluator as non-constant. Most were state labels and colors which were defaulted to "". The proper value is null for states and 0 for colors.
- also replaced all "" defaults for names with "none".
- added a TESTN instruction. This is like TEST but negates the operand. This was added to avoid flooding the constant table with too many case labels. With TEST and TESTN combined, all numbers between -65535 and 65535 can be kept entirely inside the instruction. Numbers outside this range still use a BEQ instruction.
- fixed: FxBinary::ResolveLR' check for numeric operations was incomplete. Like far too many other places it just assumed that everything with ValueType->GetRegType() == REGT_INT is a numeric type, but for names this is not the case.
- added a descriptive name to all types for error messages.
- added a generic type cast node to the code generator.
- added a few more cast operations to the 'cast' VM instruction.
- extended FxClassTypeCast to handle all possible input that can be cast to a class pointer, not just names.
* 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.
