Fixed a case where partial trigger pull could be bound to another button
There is a fundamental problem not resolved by this commit:
Some controllers have axes (triggers, pedals, etc.) that don't start at zero, but we're guaranteed that if we get a value that it's correct. For these controllers, the current code works, where we take the first value we get and use that as the zero point and generate axis motion starting from that point on.
Other controllers have digital axes (D-pad) that assume a zero starting point, and the first value we get is the min or max axis value when the D-pad is moved. For these controllers, the current code thinks that the zero point is the axis value after the D-pad motion and this doesn't work.
My hypothesis is that the first class of devices is more common and that we should solve for that, and add an exception to SDL_JoystickAxesCenteredAtZero() as needed for the second class of devices.
This adds support for all XInput devices, exposed through the SDL joystick API.
The button and axis reporting for XInput devices has been changed to match DirectInput and other platforms.
The game controller xinput mapping has been updated so this change is seamless.
There is a new hint, SDL_HINT_XINPUT_USE_OLD_JOYSTICK_MAPPING, for any applications that have hardcoded the old xinput button and axis set. This hint will be removed in SDL 2.1.
It was simpler to just have the polling (actually: hotplug detection)
functions return immediately if it's not an appropriate time to poll.
Note that previously, if any joystick/controller was opened, we would poll
every time anyhow, skipping this function.
Check the hint at initialization time, as an optimization. This isn't something we expect the application to change at runtime, and if it is we should add an API for it.
This changes makes it so that you only receive joystick (and implicitly
gamecontroller) input events when your application has keyboard focus.
If you'd like to still receive events when your application is in the
background, set the SDL_JOYSTICK_ALLOW_BACKGROUND_EVENTS hint to "1".
This fixes http://bugzilla.libsdl.org/show_bug.cgi?id=1892
This lets us change things like this...
if (Failed) {
SDL_SetError("We failed");
return -1;
}
...into this...
if (Failed) {
return SDL_SetError("We failed");
}
Fixes Bugzilla #1778.
