i.e. where the string is known guaranteed to be WCHAR*, in:
- SDL_dinputjoystick.c (WIN_IsXInputDevice): VARIANT->var is BSTR (WCHAR*)
- SDL_rawinputjoystick.c (RAWINPUT_AddDevice): string is WCHAR*
- SDL_windows_gaming_input.c (IEventHandler_CRawGameControllerVtbl_InvokeAdded):
string is WCHAR*
There should be more of these..
Joel Linn
TLDR; https://godbolt.org/z/43fd8G
Let's deduce this from C++ reference code:
https://docs.microsoft.com/en-us/cpp/cppcx/wrl/how-to-activate-and-use-a-windows-runtime-component-using-wrl?view=msvc-160
At the bottom of the page there is this snippet:
```
int wmain()
{
/* ... more code ... */
// Get the domain part of the URI.
HString domainName;
hr = uri->get_Domain(domainName.GetAddressOf());
if (FAILED(hr))
{
return PrintError(__LINE__, hr);
}
// Print the domain name and return.
wprintf_s(L"Domain name: %s\n", domainName.GetRawBuffer(nullptr));
// All smart pointers and RAII objects go out of scope here.
}
```
`HString` is defined in `corewrappers.h` and the call chain for the destructor is:
`~HString() -> Release() -> ::WindowsDeleteString()`
QED
Joel Linn
Eliminate additional heap allocation for short-lived HSTRINGs.
Uses `WindowsCreateStringReference()` to disable reference counting and memory management by the Window Runtime.
This fixes bad report parsing for various newer Xbox controllers, and this driver is now preferred over XInput, since it handles more than 4 controllers.
Added support for the PS4 controller gyro and accelerometer on iOS and HIDAPI drivers
Also fixed an issue with the accelerometer on iOS having inverted axes
Joel Linn
This fixes two types of MSVC compiler warnings.
- One parameter in the function signatures of two WGI event handlers had one level of indirection too much (and did not match Windows SDK headers). The indirection was cast away so it still worked.
- size_t was implicitly cast to UINT32 for a number of (constant) string lengths.
Jan Bujak
I wrote a new driver for my gamepad on Linux. I'd like SDL to support it out-of-box, as currently it just treats it as a generic joystick instead of a gamepad. From what I can see the only way to do that is to either 1) pick one of the already supported controllers' PID, VID and button layouts and have my driver send that (effectively lying that it's something else), or 2) submit a preconfigured, hardcoded mapping to SDL.
Both of those, in my opinion, are silly when we already have the Linux Gamepad Specification which standarizes this:
https://www.kernel.org/doc/html/v4.15/input/gamepad.html
Unfortunately SDL doesn't make use of it currently. So I've took it upon myself to add it; patch is in the attachments.
Basically what the patch does is that if SDL finds no built-it controller mappings for a given joystick it then asks the joystick backend to autodetect it, and that uses the relevant evdev bits to figure out which button/axis is which. (See the specs for more details.)
With this patch applied my own driver for my controller works out-of-box with SDL with no extra configuration and is correctly recognized as a gamepad; this is also going to be the case for any other driver which follows the Linux Gamepad Specification.
This driver supports the Razer Atrox Arcade Stick
Some of the quirks of this driver, inherent in Windows Gaming Input:
* There will never appear to be controllers connected at startup. You must support hot-plugging in order to see these controllers.
* You can't read the state of the guide button
* You can't get controller events in the background
Cameron Gutman
Sam Lantinga
Ozkan Sezer