1 files changed, 298 insertions, 0 deletions

diff --git a/contrib/SDL-3.2.8/src/joystick/n3ds/SDL_sysjoystick.c b/contrib/SDL-3.2.8/src/joystick/n3ds/SDL_sysjoystick.c
new file mode 100644
index 0000000..8396ac5
--- /dev/null
+++ b/contrib/SDL-3.2.8/src/joystick/n3ds/SDL_sysjoystick.c
@@ -0,0 +1,298 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2025 Sam Lantinga <slouken@libsdl.org>
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+*/
+#include "SDL_internal.h"
+
+#ifdef SDL_JOYSTICK_N3DS
+
+// This is the N3DS implementation of the SDL joystick API
+
+#include <3ds.h>
+
+#include "../SDL_sysjoystick.h"
+
+#define NB_BUTTONS 23
+
+/*
+  N3DS sticks values are roughly within +/-160
+  which is too small to pass the jitter tolerance.
+  This correction is applied to axis values
+  so they fit better in SDL's value range.
+*/
+static inline int Correct_Axis_X(int X) {
+    if (X > 160) {
+        return SDL_JOYSTICK_AXIS_MAX;
+    }
+    else if (X < -160) {
+        return -SDL_JOYSTICK_AXIS_MAX;
+    }
+    return (X * SDL_JOYSTICK_AXIS_MAX) / 160;
+}
+
+/*
+  The Y axis needs to be flipped because SDL's "up"
+  is reversed compared to libctru's "up"
+*/
+static inline int Correct_Axis_Y(int Y) {
+    return Correct_Axis_X(-Y);
+}
+
+static void UpdateN3DSPressedButtons(Uint64 timestamp, SDL_Joystick *joystick);
+static void UpdateN3DSReleasedButtons(Uint64 timestamp, SDL_Joystick *joystick);
+static void UpdateN3DSCircle(Uint64 timestamp, SDL_Joystick *joystick);
+static void UpdateN3DSCStick(Uint64 timestamp, SDL_Joystick *joystick);
+
+static bool N3DS_JoystickInit(void)
+{
+    hidInit();
+    SDL_PrivateJoystickAdded(1);
+    return true;
+}
+
+static const char *N3DS_JoystickGetDeviceName(int device_index)
+{
+    return "Nintendo 3DS";
+}
+
+static int N3DS_JoystickGetCount(void)
+{
+    return 1;
+}
+
+static SDL_GUID N3DS_JoystickGetDeviceGUID(int device_index)
+{
+    SDL_GUID guid = SDL_CreateJoystickGUIDForName("Nintendo 3DS");
+    return guid;
+}
+
+static SDL_JoystickID N3DS_JoystickGetDeviceInstanceID(int device_index)
+{
+    return device_index + 1;
+}
+
+static bool N3DS_JoystickOpen(SDL_Joystick *joystick, int device_index)
+{
+    joystick->nbuttons = NB_BUTTONS;
+    joystick->naxes = 4;
+    joystick->nhats = 0;
+
+    return true;
+}
+
+static bool N3DS_JoystickSetSensorsEnabled(SDL_Joystick *joystick, bool enabled)
+{
+    return SDL_Unsupported();
+}
+
+static void N3DS_JoystickUpdate(SDL_Joystick *joystick)
+{
+    Uint64 timestamp = SDL_GetTicksNS();
+
+    UpdateN3DSPressedButtons(timestamp, joystick);
+    UpdateN3DSReleasedButtons(timestamp, joystick);
+    UpdateN3DSCircle(timestamp, joystick);
+    UpdateN3DSCStick(timestamp, joystick);
+}
+
+static void UpdateN3DSPressedButtons(Uint64 timestamp, SDL_Joystick *joystick)
+{
+    static u32 previous_state = 0;
+    u32 updated_down;
+    u32 current_state = hidKeysDown();
+    updated_down = previous_state ^ current_state;
+    if (updated_down) {
+        for (Uint8 i = 0; i < joystick->nbuttons; i++) {
+            if (current_state & BIT(i) & updated_down) {
+                SDL_SendJoystickButton(timestamp, joystick, i, true);
+            }
+        }
+    }
+    previous_state = current_state;
+}
+
+static void UpdateN3DSReleasedButtons(Uint64 timestamp, SDL_Joystick *joystick)
+{
+    static u32 previous_state = 0;
+    u32 updated_up;
+    u32 current_state = hidKeysUp();
+    updated_up = previous_state ^ current_state;
+    if (updated_up) {
+        for (Uint8 i = 0; i < joystick->nbuttons; i++) {
+            if (current_state & BIT(i) & updated_up) {
+                SDL_SendJoystickButton(timestamp, joystick, i, false);
+            }
+        }
+    }
+    previous_state = current_state;
+}
+
+static void UpdateN3DSCircle(Uint64 timestamp, SDL_Joystick *joystick)
+{
+    static circlePosition previous_state = { 0, 0 };
+    circlePosition current_state;
+    hidCircleRead(&current_state);
+    if (previous_state.dx != current_state.dx) {
+        SDL_SendJoystickAxis(timestamp, joystick,
+                                0,
+                                Correct_Axis_X(current_state.dx));
+    }
+    if (previous_state.dy != current_state.dy) {
+        SDL_SendJoystickAxis(timestamp, joystick,
+                                1,
+                                Correct_Axis_Y(current_state.dy));
+    }
+    previous_state = current_state;
+}
+
+static void UpdateN3DSCStick(Uint64 timestamp, SDL_Joystick *joystick)
+{
+    static circlePosition previous_state = { 0, 0 };
+    circlePosition current_state;
+    hidCstickRead(&current_state);
+    if (previous_state.dx != current_state.dx) {
+        SDL_SendJoystickAxis(timestamp, joystick,
+                                2,
+                                Correct_Axis_X(current_state.dx));
+    }
+    if (previous_state.dy != current_state.dy) {
+        SDL_SendJoystickAxis(timestamp, joystick,
+                                3,
+                                Correct_Axis_Y(current_state.dy));
+    }
+    previous_state = current_state;
+}
+
+static void N3DS_JoystickClose(SDL_Joystick *joystick)
+{
+}
+
+static void N3DS_JoystickQuit(void)
+{
+    hidExit();
+}
+
+static bool N3DS_JoystickGetGamepadMapping(int device_index, SDL_GamepadMapping *out)
+{
+    // There is only one possible mapping.
+    *out = (SDL_GamepadMapping){
+        .a = { EMappingKind_Button, 0 },
+        .b = { EMappingKind_Button, 1 },
+        .x = { EMappingKind_Button, 10 },
+        .y = { EMappingKind_Button, 11 },
+        .back = { EMappingKind_Button, 2 },
+        .guide = { EMappingKind_None, 255 },
+        .start = { EMappingKind_Button, 3 },
+        .leftstick = { EMappingKind_None, 255 },
+        .rightstick = { EMappingKind_None, 255 },
+        .leftshoulder = { EMappingKind_Button, 9 },
+        .rightshoulder = { EMappingKind_Button, 8 },
+        .dpup = { EMappingKind_Button, 6 },
+        .dpdown = { EMappingKind_Button, 7 },
+        .dpleft = { EMappingKind_Button, 5 },
+        .dpright = { EMappingKind_Button, 4 },
+        .misc1 = { EMappingKind_None, 255 },
+        .right_paddle1 = { EMappingKind_None, 255 },
+        .left_paddle1 = { EMappingKind_None, 255 },
+        .right_paddle2 = { EMappingKind_None, 255 },
+        .left_paddle2 = { EMappingKind_None, 255 },
+        .leftx = { EMappingKind_Axis, 0 },
+        .lefty = { EMappingKind_Axis, 1 },
+        .rightx = { EMappingKind_Axis, 2 },
+        .righty = { EMappingKind_Axis, 3 },
+        .lefttrigger = { EMappingKind_Button, 14 },
+        .righttrigger = { EMappingKind_Button, 15 },
+    };
+    return true;
+}
+
+static void N3DS_JoystickDetect(void)
+{
+}
+
+static bool N3DS_JoystickIsDevicePresent(Uint16 vendor_id, Uint16 product_id, Uint16 version, const char *name)
+{
+    // We don't override any other drivers
+    return false;
+}
+
+static const char *N3DS_JoystickGetDevicePath(int device_index)
+{
+    return NULL;
+}
+
+static int N3DS_JoystickGetDeviceSteamVirtualGamepadSlot(int device_index)
+{
+    return -1;
+}
+
+static int N3DS_JoystickGetDevicePlayerIndex(int device_index)
+{
+    return -1;
+}
+
+static void N3DS_JoystickSetDevicePlayerIndex(int device_index, int player_index)
+{
+}
+
+static bool N3DS_JoystickRumble(SDL_Joystick *joystick, Uint16 low_frequency_rumble, Uint16 high_frequency_rumble)
+{
+    return SDL_Unsupported();
+}
+
+static bool N3DS_JoystickRumbleTriggers(SDL_Joystick *joystick, Uint16 left_rumble, Uint16 right_rumble)
+{
+    return SDL_Unsupported();
+}
+
+static bool N3DS_JoystickSetLED(SDL_Joystick *joystick, Uint8 red, Uint8 green, Uint8 blue)
+{
+    return SDL_Unsupported();
+}
+
+static bool N3DS_JoystickSendEffect(SDL_Joystick *joystick, const void *data, int size)
+{
+    return SDL_Unsupported();
+}
+
+SDL_JoystickDriver SDL_N3DS_JoystickDriver = {
+    N3DS_JoystickInit,
+    N3DS_JoystickGetCount,
+    N3DS_JoystickDetect,
+    N3DS_JoystickIsDevicePresent,
+    N3DS_JoystickGetDeviceName,
+    N3DS_JoystickGetDevicePath,
+    N3DS_JoystickGetDeviceSteamVirtualGamepadSlot,
+    N3DS_JoystickGetDevicePlayerIndex,
+    N3DS_JoystickSetDevicePlayerIndex,
+    N3DS_JoystickGetDeviceGUID,
+    N3DS_JoystickGetDeviceInstanceID,
+    N3DS_JoystickOpen,
+    N3DS_JoystickRumble,
+    N3DS_JoystickRumbleTriggers,
+    N3DS_JoystickSetLED,
+    N3DS_JoystickSendEffect,
+    N3DS_JoystickSetSensorsEnabled,
+    N3DS_JoystickUpdate,
+    N3DS_JoystickClose,
+    N3DS_JoystickQuit,
+    N3DS_JoystickGetGamepadMapping
+};
+
+#endif // SDL_JOYSTICK_N3DS