Added the hint SDL_HINT_GAMECONTROLLER_USE_BUTTON_LABELS to control whether Nintendo Switch controllers use their button labels or button positions for game controller button reporting.

include/SDL_hints.h

@@ -488,6 +488,29 @@ extern "C" {
  */
 #define SDL_HINT_GAMECONTROLLER_IGNORE_DEVICES_EXCEPT "SDL_GAMECONTROLLER_IGNORE_DEVICES_EXCEPT"
 
+/**
+ *  \brief  If set, game controller face buttons report their values according to their labels instead of their positional layout.
+ * 
+ *  For example, on Nintendo Switch controllers, normally you'd get:
+ *
+ *      (Y)
+ *  (X)     (B)
+ *      (A)
+ *
+ *  but if this hint is set, you'll get:
+ *
+ *      (X)
+ *  (Y)     (A)
+ *      (B)
+ *
+ *  The variable can be set to the following values:
+ *    "0"       - Report the face buttons by position, as though they were on an Xbox controller.
+ *    "1"       - Report the face buttons by label instead of position
+ *
+ *  The default value is "0".  This hint may be set at any time.
+ */
+#define SDL_HINT_GAMECONTROLLER_USE_BUTTON_LABELS "SDL_GAMECONTROLLER_USE_BUTTON_LABELS"
+
 /**
  *  \brief  A variable that lets you enable joystick (and gamecontroller) events even when your app is in the background.
  *

src/joystick/hidapi/SDL_hidapi_switch.c

@@ -192,8 +192,9 @@ typedef struct
 
 typedef struct {
     hid_device *dev;
-    SDL_bool m_bIsInputOnly;
+    SDL_bool m_bInputOnly;
-    SDL_bool m_bIsUsingBluetooth;
+    SDL_bool m_bUsingBluetooth;
+    SDL_bool m_bUseButtonLabels;
     Uint8 m_nCommandNumber;
     SwitchCommonOutputPacket_t m_RumblePacket;
     Uint32 m_nRumbleExpiration;
@@ -313,7 +314,7 @@ static void ConstructSubcommand(SDL_DriverSwitch_Context *ctx, ESwitchSubcommand
 static SDL_bool WritePacket(SDL_DriverSwitch_Context *ctx, void *pBuf, Uint8 ucLen)
 {
     Uint8 rgucBuf[k_unSwitchMaxOutputPacketLength];
-    const size_t unWriteSize = ctx->m_bIsUsingBluetooth ? k_unSwitchBluetoothPacketLength : k_unSwitchUSBPacketLength;
+    const size_t unWriteSize = ctx->m_bUsingBluetooth ? k_unSwitchBluetoothPacketLength : k_unSwitchUSBPacketLength;
 
     if (ucLen > k_unSwitchOutputPacketDataLength) {
         return SDL_FALSE;
@@ -526,7 +527,7 @@ static SDL_bool LoadStickCalibration(SDL_DriverSwitch_Context *ctx)
         }
     }
 
-    if (ctx->m_bIsUsingBluetooth) {
+    if (ctx->m_bUsingBluetooth) {
         for (stick = 0; stick < 2; ++stick) {
             for(axis = 0; axis < 2; ++axis) {
                 ctx->m_StickExtents[stick].axis[axis].sMin = (Sint16)(SDL_MIN_SINT16 * 0.5f);
@@ -580,6 +581,31 @@ static Sint16 ApplyStickCalibration(SDL_DriverSwitch_Context *ctx, int nStick, i
     return ApplyStickCalibrationCentered(ctx, nStick, nAxis, sRawValue, ctx->m_StickCalData[nStick].axis[nAxis].sCenter);
 }
 
+static void SDLCALL SDL_GameControllerButtonReportingHintChanged(void *userdata, const char *name, const char *oldValue, const char *hint)
+{
+    SDL_DriverSwitch_Context *ctx = (SDL_DriverSwitch_Context *)userdata;
+    ctx->m_bUseButtonLabels = (hint && *hint != '0' && SDL_strcasecmp(hint, "false") != 0);
+}
+
+static Uint8 RemapButton(SDL_DriverSwitch_Context *ctx, Uint8 button)
+{
+    if (ctx->m_bUseButtonLabels) {
+        switch (button) {
+        case SDL_CONTROLLER_BUTTON_A:
+            return SDL_CONTROLLER_BUTTON_B;
+        case SDL_CONTROLLER_BUTTON_B:
+            return SDL_CONTROLLER_BUTTON_A;
+        case SDL_CONTROLLER_BUTTON_X:
+            return SDL_CONTROLLER_BUTTON_Y;
+        case SDL_CONTROLLER_BUTTON_Y:
+            return SDL_CONTROLLER_BUTTON_X;
+        default:
+            break;
+        }
+    }
+    return button;
+}
+        
 static SDL_bool
 HIDAPI_DriverSwitch_Init(SDL_Joystick *joystick, hid_device *dev, Uint16 vendor_id, Uint16 product_id, void **context)
 {
@@ -596,15 +622,15 @@ HIDAPI_DriverSwitch_Init(SDL_Joystick *joystick, hid_device *dev, Uint16 vendor_
     *context = ctx;
 
     /* Find out whether or not we can send output reports */
-    ctx->m_bIsInputOnly = SDL_IsJoystickNintendoSwitchProInputOnly(vendor_id, product_id);
+    ctx->m_bInputOnly = SDL_IsJoystickNintendoSwitchProInputOnly(vendor_id, product_id);
-    if (!ctx->m_bIsInputOnly) {
+    if (!ctx->m_bInputOnly) {
         /* Initialize rumble data */
         SetNeutralRumble(&ctx->m_RumblePacket.rumbleData[0]);
         SetNeutralRumble(&ctx->m_RumblePacket.rumbleData[1]);
 
         /* Try setting up USB mode, and if that fails we're using Bluetooth */
         if (!BTrySetupUSB(ctx)) {
-            ctx->m_bIsUsingBluetooth = SDL_TRUE;
+            ctx->m_bUsingBluetooth = SDL_TRUE;
         }
 
         if (!LoadStickCalibration(ctx)) {
@@ -620,7 +646,7 @@ HIDAPI_DriverSwitch_Init(SDL_Joystick *joystick, hid_device *dev, Uint16 vendor_
         }
 
         /* Set the desired input mode */
-        if (ctx->m_bIsUsingBluetooth) {
+        if (ctx->m_bUsingBluetooth) {
             input_mode = k_eSwitchInputReportIDs_SimpleControllerState;
         } else {
             input_mode = k_eSwitchInputReportIDs_FullControllerState;
@@ -632,7 +658,7 @@ HIDAPI_DriverSwitch_Init(SDL_Joystick *joystick, hid_device *dev, Uint16 vendor_
         }
 
         /* Start sending USB reports */
-        if (!ctx->m_bIsUsingBluetooth) {
+        if (!ctx->m_bUsingBluetooth) {
             /* ForceUSB doesn't generate an ACK, so don't wait for a reply */
             if (!WriteProprietary(ctx, k_eSwitchProprietaryCommandIDs_ForceUSB, NULL, 0, SDL_FALSE)) {
                 SDL_SetError("Couldn't start USB reports");
@@ -646,6 +672,14 @@ HIDAPI_DriverSwitch_Init(SDL_Joystick *joystick, hid_device *dev, Uint16 vendor_
         SetSlotLED(ctx, (joystick->instance_id % 4));
     }
 
+    if (vendor_id == 0x0e6f && product_id == 0x0185) {
+        /* This is a controller shaped like a GameCube controller, with a large central A button */
+        ctx->m_bUseButtonLabels = SDL_TRUE;
+    } else {
+        SDL_AddHintCallback(SDL_HINT_GAMECONTROLLER_USE_BUTTON_LABELS,
+                            SDL_GameControllerButtonReportingHintChanged, ctx);
+    }
+
     /* Initialize the joystick capabilities */
     joystick->nbuttons = SDL_CONTROLLER_BUTTON_MAX;
     joystick->naxes = SDL_CONTROLLER_AXIS_MAX;
@@ -701,10 +735,10 @@ static void HandleInputOnlyControllerState(SDL_Joystick *joystick, SDL_DriverSwi
 
     if (packet->rgucButtons[0] != ctx->m_lastInputOnlyState.rgucButtons[0]) {
         Uint8 data = packet->rgucButtons[0];
-        SDL_PrivateJoystickButton(joystick, SDL_CONTROLLER_BUTTON_X, (data & 0x01) ? SDL_PRESSED : SDL_RELEASED);
+        SDL_PrivateJoystickButton(joystick, RemapButton(ctx, SDL_CONTROLLER_BUTTON_X), (data & 0x01) ? SDL_PRESSED : SDL_RELEASED);
-        SDL_PrivateJoystickButton(joystick, SDL_CONTROLLER_BUTTON_A, (data & 0x02) ? SDL_PRESSED : SDL_RELEASED);
+        SDL_PrivateJoystickButton(joystick, RemapButton(ctx, SDL_CONTROLLER_BUTTON_A), (data & 0x02) ? SDL_PRESSED : SDL_RELEASED);
-        SDL_PrivateJoystickButton(joystick, SDL_CONTROLLER_BUTTON_B, (data & 0x04) ? SDL_PRESSED : SDL_RELEASED);
+        SDL_PrivateJoystickButton(joystick, RemapButton(ctx, SDL_CONTROLLER_BUTTON_B), (data & 0x04) ? SDL_PRESSED : SDL_RELEASED);
-        SDL_PrivateJoystickButton(joystick, SDL_CONTROLLER_BUTTON_Y, (data & 0x08) ? SDL_PRESSED : SDL_RELEASED);
+        SDL_PrivateJoystickButton(joystick, RemapButton(ctx, SDL_CONTROLLER_BUTTON_Y), (data & 0x08) ? SDL_PRESSED : SDL_RELEASED);
         SDL_PrivateJoystickButton(joystick, SDL_CONTROLLER_BUTTON_LEFTSHOULDER, (data & 0x10) ? SDL_PRESSED : SDL_RELEASED);
         SDL_PrivateJoystickButton(joystick, SDL_CONTROLLER_BUTTON_RIGHTSHOULDER, (data & 0x20) ? SDL_PRESSED : SDL_RELEASED);
 
@@ -799,10 +833,10 @@ static void HandleSimpleControllerState(SDL_Joystick *joystick, SDL_DriverSwitch
 
     if (packet->rgucButtons[0] != ctx->m_lastSimpleState.rgucButtons[0]) {
         Uint8 data = packet->rgucButtons[0];
-        SDL_PrivateJoystickButton(joystick, SDL_CONTROLLER_BUTTON_A, (data & 0x01) ? SDL_PRESSED : SDL_RELEASED);
+        SDL_PrivateJoystickButton(joystick, RemapButton(ctx, SDL_CONTROLLER_BUTTON_A), (data & 0x01) ? SDL_PRESSED : SDL_RELEASED);
-        SDL_PrivateJoystickButton(joystick, SDL_CONTROLLER_BUTTON_B, (data & 0x02) ? SDL_PRESSED : SDL_RELEASED);
+        SDL_PrivateJoystickButton(joystick, RemapButton(ctx, SDL_CONTROLLER_BUTTON_B), (data & 0x02) ? SDL_PRESSED : SDL_RELEASED);
-        SDL_PrivateJoystickButton(joystick, SDL_CONTROLLER_BUTTON_X, (data & 0x04) ? SDL_PRESSED : SDL_RELEASED);
+        SDL_PrivateJoystickButton(joystick, RemapButton(ctx, SDL_CONTROLLER_BUTTON_X), (data & 0x04) ? SDL_PRESSED : SDL_RELEASED);
-        SDL_PrivateJoystickButton(joystick, SDL_CONTROLLER_BUTTON_Y, (data & 0x08) ? SDL_PRESSED : SDL_RELEASED);
+        SDL_PrivateJoystickButton(joystick, RemapButton(ctx, SDL_CONTROLLER_BUTTON_Y), (data & 0x08) ? SDL_PRESSED : SDL_RELEASED);
         SDL_PrivateJoystickButton(joystick, SDL_CONTROLLER_BUTTON_LEFTSHOULDER, (data & 0x10) ? SDL_PRESSED : SDL_RELEASED);
         SDL_PrivateJoystickButton(joystick, SDL_CONTROLLER_BUTTON_RIGHTSHOULDER, (data & 0x20) ? SDL_PRESSED : SDL_RELEASED);
 
@@ -887,10 +921,10 @@ static void HandleFullControllerState(SDL_Joystick *joystick, SDL_DriverSwitch_C
 
     if (packet->controllerState.rgucButtons[0] != ctx->m_lastFullState.controllerState.rgucButtons[0]) {
         Uint8 data = packet->controllerState.rgucButtons[0];
-        SDL_PrivateJoystickButton(joystick, SDL_CONTROLLER_BUTTON_X, (data & 0x01) ? SDL_PRESSED : SDL_RELEASED);
+        SDL_PrivateJoystickButton(joystick, RemapButton(ctx, SDL_CONTROLLER_BUTTON_X), (data & 0x01) ? SDL_PRESSED : SDL_RELEASED);
-        SDL_PrivateJoystickButton(joystick, SDL_CONTROLLER_BUTTON_Y, (data & 0x02) ? SDL_PRESSED : SDL_RELEASED);
+        SDL_PrivateJoystickButton(joystick, RemapButton(ctx, SDL_CONTROLLER_BUTTON_Y), (data & 0x02) ? SDL_PRESSED : SDL_RELEASED);
-        SDL_PrivateJoystickButton(joystick, SDL_CONTROLLER_BUTTON_A, (data & 0x04) ? SDL_PRESSED : SDL_RELEASED);
+        SDL_PrivateJoystickButton(joystick, RemapButton(ctx, SDL_CONTROLLER_BUTTON_A), (data & 0x04) ? SDL_PRESSED : SDL_RELEASED);
-        SDL_PrivateJoystickButton(joystick, SDL_CONTROLLER_BUTTON_B, (data & 0x08) ? SDL_PRESSED : SDL_RELEASED);
+        SDL_PrivateJoystickButton(joystick, RemapButton(ctx, SDL_CONTROLLER_BUTTON_B), (data & 0x08) ? SDL_PRESSED : SDL_RELEASED);
         SDL_PrivateJoystickButton(joystick, SDL_CONTROLLER_BUTTON_RIGHTSHOULDER, (data & 0x40) ? SDL_PRESSED : SDL_RELEASED);
         axis = (data & 0x80) ? 32767 : -32768;
         SDL_PrivateJoystickAxis(joystick, SDL_CONTROLLER_AXIS_TRIGGERRIGHT, axis);
@@ -964,7 +998,7 @@ HIDAPI_DriverSwitch_Update(SDL_Joystick *joystick, hid_device *dev, void *contex
     int size;
 
     while ((size = ReadInput(ctx)) > 0) {
-        if (ctx->m_bIsInputOnly) {
+        if (ctx->m_bInputOnly) {
             HandleInputOnlyControllerState(joystick, ctx, (SwitchInputOnlyControllerStatePacket_t *)&ctx->m_rgucReadBuffer[0]);
         } else {
             switch (ctx->m_rgucReadBuffer[0]) {
@@ -995,8 +1029,13 @@ HIDAPI_DriverSwitch_Quit(SDL_Joystick *joystick, hid_device *dev, void *context)
 {
     SDL_DriverSwitch_Context *ctx = (SDL_DriverSwitch_Context *)context;
 
+    if (!ctx->m_bInputOnly) {
         /* Restore simple input mode for other applications */
         SetInputMode(ctx, k_eSwitchInputReportIDs_SimpleControllerState);
+    }
+
+    SDL_DelHintCallback(SDL_HINT_GAMECONTROLLER_USE_BUTTON_LABELS,
+                        SDL_GameControllerButtonReportingHintChanged, ctx);
 
     SDL_free(context);
 }