Main:
- It's now implemented thanks to `<mutex>`. No more platform-specific implementations.
- `BinaryMutex` (non-recursive) is added, as an alternative for special cases.
- Doesn't need allocation/deallocation anymore. It can live in the stack and be part of other classes.
- Because of that, it's methods are now `const` and the inner mutex is `mutable` so it can be easily used in `const` contexts.
- A no-op implementation is provided if `NO_THREADS` is defined. No more need to add `#ifdef NO_THREADS` just for this.
- `MutexLock` now takes a reference. At this point the cases of null `Mutex`es are rare. If you ever need that, just don't use `MutexLock`.
- Thread-safe utilities are therefore simpler now.
Misc.:
- `ScopedMutexLock` is dropped and replaced by `MutexLock`, because they were pretty much the same.
- Every case of lock, do-something, unlock is replaced by `MutexLock` (complex cases where it's not straightfoward are kept as as explicit lock and unlock).
- `ShaderRD` contained an `std::mutex`, which has been replaced by `Mutex`.
- Added missing links to the Control node in BoxContainer
- Added Oxford commas in BoxContainer and CanvasItem
- Clarified ambiguous boolean wording in BoxContainer
- Improved paragraphing in ScrollContainer's description
- Simplified ControlPicker description
Although destructor call was missing, it still doesn't heal #36537 memory leaks. Further description how that might be overcome - on GitHub
Partialy covers #36537
- Renames PackedIntArray to PackedInt32Array.
- Renames PackedFloatArray to PackedFloat32Array.
- Adds PackedInt64Array and PackedFloat64Array.
- Renames Variant::REAL to Variant::FLOAT for consistency.
Packed arrays are for storing large amount of data and creating stuff like
meshes, buffers. textures, etc. Forcing them to be 64 is a huge waste of
memory. That said, many users requested the ability to have 64 bits packed
arrays for their games, so this is just an optional added type.
For Variant, the float datatype is always 64 bits, and exposed as `float`.
We still have `real_t` which is the datatype that can change from 32 to 64
bits depending on a compile flag (not entirely working right now, but that's
the idea). It affects math related datatypes and code only.
Neither Variant nor PackedArray make use of real_t, which is only intended
for math precision, so the term is removed from there to keep only float.
Was missed in #36393 because no `callable_mp()` calls were actually
compiled with `tools=no` in that PR.
Also work around GCC warning that also affects the
`call_with_variant_args_ret_helper` variant.
Arrays inside of Variant are unique and use reference counting.
When you assign a variant containing a packed array to another, or
when you call non const functions to arrays, this will work even
if the array is inside a dictionary, so they will from now pass
as reference.
The difference with regular variant arrays is that, once passed
to a function in the C++ API, they are no longer shared. This is
required for security and thread safety, as those arrays are
mainly used to pass data back and forth even between threads.
