Originally, Layer contained a std::map of Sections, which containted a std::map
containing the (key, value) pairs. Here we flattern this structure so that only
one std::map is required, reducing the number of indirections required and
vastly simplifying the code.
No code is relying on this unexplained null byte check, since
the only code that calls UTF16ToUTF8 on non-Windows systems
is UTF16BEToUTF8, which explicitly strips null bytes.
Axis range was previously calculated as max + abs(min), which relies on the assumption that
min will not exceed 0. For (min, max) values like (0, 255) or (-128, 127), which I assume to
be the most common cases, the range is correctly calculated as 255. However, given (20,
235), the range is erroneously calculated as 255, leading to axis values being normalized
incorrectly.
SDL already handles this case correctly. After changing the range calculation to max - min,
the axis values received from the evdev backend are practically identical to the values
received from the SDL backend.
This has no effect now, as we've never bumped the database version.
Instead, it adds future proofing, and makes moving between a future
version with a bump and master clean.
We shouldn't try to create folder names that contain characters
such as : or / since they are forbidden or have special meanings.
(No officially released disc uses such characters, though.)
Now that all inputs are corrected to zero-centered, we can use getFlat()
to ignore movements that are just noise.
This eliminates a lot of drift when the controller is at rest, notably
on the character select screen in Melee.
Android reports the same physical axis multiple times for analog
triggers, and this handles this case.
There are also some controllers with broken mappings (eg the analog
triggers on a PS4 DualShock 4). These axis don't center correctly.
There are also some controllers (again, the PS4) that send both a button
press and an axis movement. This ignores the buttons so we can use the
analog axis. Otherwise, since the button comes before the axis moves
far we would always take the button.