LinGao
We build SDL with Visual studio 2017 compiler on Windows Server 2016, but it failed to build due to error LNK2019: unresolved external symbol memset referenced in function SDL_SetJoystickIDForPlayerIndex with MSVC x64 on Windows on latest default branch. And we found that it can be first reproduced on 0fff06175109 changeset. Could you please help have a look about this issue? Thanks in advance!
Steps to Reproduce:
1.hg clone https://hg.libsdl.org/SDL D:\SDL\src
2.Open a VS 2017 x64 command prompt as admin and browse to D:\SDL
3.msbuild /p:Configuration=Release /p:Platform=x64 /p:WindowsTargetPlatformVersion=10.0.17134.0 VisualC\SDL.sln /t:Rebuild
Actual result:
Creating library D:\SDL\src\VisualC\x64\Release\SDL2.lib and object D:\SDL\src\VisualC\x64\Release\SDL2.exp
SDL_joystick.obj : error LNK2019: unresolved external symbol memset referenced in function SDL_SetJoystickIDForPlayerIndex [D:\SDL\src\VisualC\SDL\SDL.vcxproj]
D:\SDL\src\VisualC\x64\Release\SDL2.dll : fatal error LNK1120: 1 unresolved externals [D:\SDL\src\VisualC\SDL\SDL.vcxproj]
Done Building Project "D:\SDL\src\VisualC\SDL\SDL.vcxproj" (Rebuild target(s)) -- FAILED.
Added the functions SDL_JoystickFromPlayerIndex(), SDL_JoystickSetPlayerIndex(), SDL_GameControllerFromPlayerIndex(), and SDL_GameControllerSetPlayerIndex()
It causes the HIDAPI devices to always be opened on enumeration, which causes crashes in the Windows drivers when multiple applications are reading and writing at the same time. We can revisit this after 2.0.10 release.
Note that a single USB device is responsible for all 4 joysticks, so a large
rewrite of the DeviceDriver functions was necessary to allow a single device to
produce multiple joysticks.
Daniel Gibson
Even though my game (dhewm3) doesn't use SDL_INIT_JOYSTICK, SDL_PumpEvent() calls SDL_JoystickUpdate() which ends up calling hid_enumerate() every three seconds, and sometimes on my Win7 box hid_enumerate() takes about 5 seconds, which causes the whole game to freeze for that time.
The code is now reliant on SDL_PrivateJoystickAdded() and SDL_PrivateJoystickRemoved() being called correctly when devices are added or removed on Windows
Edward Rudd
Device: Logitech Rumble Gamepad F510 in Xinput mode.
Upon opening the joystick the values of the axes are queried via PollAllValues are not actually set on the device all the time.
This can easily be seen in the testjoystick or testgamecontroller test programs,as the testjoystick shows all axes in the center until one 'tickles' the triggers., and the testgamecontroller will show the triggers as 'on' until on 'tickles' the triggers.
Upon further research the culprit is the SDL_HINT_JOYSTICK_ALLOW_BACKGROUND_EVENTS hint. In the default value events are ignored until there is an active window, Thus in cases where the joystick system is initialized and controllers opened before the initial window is created & focuses, the initial values will be incorrect.
Here is my current workaround in the game I'm working on porting..
SDL_SetHint(SDL_HINT_JOYSTICK_ALLOW_BACKGROUND_EVENTS, "1");
SDL_GameController* gamepad = SDL_GameControllerOpen(index);
SDL_SetHint(SDL_HINT_JOYSTICK_ALLOW_BACKGROUND_EVENTS, "0");