From 16f5b9e3c33316b257c7dcc689d7df0efe6c0cae Mon Sep 17 00:00:00 2001
From: Sam Lantinga <[EMAIL REDACTED]>
Date: Wed, 5 Jan 2022 11:07:52 -0800
Subject: [PATCH] Filter jitter on Xbox One controllers when using raw input
reports
---
src/joystick/hidapi/SDL_hidapi_xboxone.c | 62 +++++++++++++++++-------
1 file changed, 45 insertions(+), 17 deletions(-)
diff --git a/src/joystick/hidapi/SDL_hidapi_xboxone.c b/src/joystick/hidapi/SDL_hidapi_xboxone.c
index cf0b0628e2d..a5a58f875db 100644
--- a/src/joystick/hidapi/SDL_hidapi_xboxone.c
+++ b/src/joystick/hidapi/SDL_hidapi_xboxone.c
@@ -43,6 +43,10 @@
#define CONTROLLER_NEGOTIATION_TIMEOUT_MS 300
#define CONTROLLER_PREPARE_INPUT_TIMEOUT_MS 50
+/* Deadzone thresholds */
+#define XINPUT_GAMEPAD_LEFT_THUMB_DEADZONE 7849
+#define XINPUT_GAMEPAD_RIGHT_THUMB_DEADZONE 8689
+#define XINPUT_GAMEPAD_TRIGGER_THRESHOLD -25058 /* Uint8 30 scaled to Sint16 full range */
/* Start controller */
static const Uint8 xboxone_init0[] = {
@@ -474,6 +478,30 @@ HIDAPI_DriverXboxOne_SetJoystickSensorsEnabled(SDL_HIDAPI_Device *device, SDL_Jo
return SDL_Unsupported();
}
+static Sint16 FilterLeftThumb(Sint16 axis)
+{
+ if (axis <= XINPUT_GAMEPAD_LEFT_THUMB_DEADZONE && axis >= -XINPUT_GAMEPAD_LEFT_THUMB_DEADZONE) {
+ return 0;
+ }
+ return axis;
+}
+
+static Sint16 FilterRightThumb(Sint16 axis)
+{
+ if (axis <= XINPUT_GAMEPAD_RIGHT_THUMB_DEADZONE && axis >= -XINPUT_GAMEPAD_RIGHT_THUMB_DEADZONE) {
+ return 0;
+ }
+ return axis;
+}
+
+static Sint16 FilterTrigger(Sint16 axis)
+{
+ if (axis <= XINPUT_GAMEPAD_TRIGGER_THRESHOLD) {
+ return 0;
+ }
+ return axis;
+}
+
static void
HIDAPI_DriverXboxOne_HandleStatePacket(SDL_Joystick *joystick, SDL_DriverXboxOne_Context *ctx, Uint8 *data, int size)
{
@@ -608,7 +636,7 @@ HIDAPI_DriverXboxOne_HandleStatePacket(SDL_Joystick *joystick, SDL_DriverXboxOne
if (axis == -32768 && size == 30 && (data[22] & 0x80) != 0) {
axis = 32767;
}
- SDL_PrivateJoystickAxis(joystick, SDL_CONTROLLER_AXIS_TRIGGERLEFT, axis);
+ SDL_PrivateJoystickAxis(joystick, SDL_CONTROLLER_AXIS_TRIGGERLEFT, FilterTrigger(axis));
axis = ((int)*(Sint16*)(&data[8]) * 64) - 32768;
if (axis == -32768 && size == 30 && (data[22] & 0x40) != 0) {
@@ -617,16 +645,16 @@ HIDAPI_DriverXboxOne_HandleStatePacket(SDL_Joystick *joystick, SDL_DriverXboxOne
if (axis == 32704) {
axis = 32767;
}
- SDL_PrivateJoystickAxis(joystick, SDL_CONTROLLER_AXIS_TRIGGERRIGHT, axis);
+ SDL_PrivateJoystickAxis(joystick, SDL_CONTROLLER_AXIS_TRIGGERRIGHT, FilterTrigger(axis));
axis = *(Sint16*)(&data[10]);
- SDL_PrivateJoystickAxis(joystick, SDL_CONTROLLER_AXIS_LEFTX, axis);
+ SDL_PrivateJoystickAxis(joystick, SDL_CONTROLLER_AXIS_LEFTX, FilterLeftThumb(axis));
axis = *(Sint16*)(&data[12]);
- SDL_PrivateJoystickAxis(joystick, SDL_CONTROLLER_AXIS_LEFTY, ~axis);
+ SDL_PrivateJoystickAxis(joystick, SDL_CONTROLLER_AXIS_LEFTY, FilterLeftThumb(~axis));
axis = *(Sint16*)(&data[14]);
- SDL_PrivateJoystickAxis(joystick, SDL_CONTROLLER_AXIS_RIGHTX, axis);
+ SDL_PrivateJoystickAxis(joystick, SDL_CONTROLLER_AXIS_RIGHTX, FilterRightThumb(axis));
axis = *(Sint16*)(&data[16]);
- SDL_PrivateJoystickAxis(joystick, SDL_CONTROLLER_AXIS_RIGHTY, ~axis);
+ SDL_PrivateJoystickAxis(joystick, SDL_CONTROLLER_AXIS_RIGHTY, FilterRightThumb(~axis));
SDL_memcpy(ctx->last_state, data, SDL_min(size, sizeof(ctx->last_state)));
}
@@ -822,26 +850,26 @@ HIDAPI_DriverXboxOneBluetooth_HandleStatePacket(SDL_Joystick *joystick, SDL_Driv
SDL_PrivateJoystickButton(joystick, SDL_CONTROLLER_BUTTON_DPAD_LEFT, dpad_left);
}
- axis = (int)*(Uint16*)(&data[1]) - 0x8000;
- SDL_PrivateJoystickAxis(joystick, SDL_CONTROLLER_AXIS_LEFTX, axis);
- axis = (int)*(Uint16*)(&data[3]) - 0x8000;
- SDL_PrivateJoystickAxis(joystick, SDL_CONTROLLER_AXIS_LEFTY, axis);
- axis = (int)*(Uint16*)(&data[5]) - 0x8000;
- SDL_PrivateJoystickAxis(joystick, SDL_CONTROLLER_AXIS_RIGHTX, axis);
- axis = (int)*(Uint16*)(&data[7]) - 0x8000;
- SDL_PrivateJoystickAxis(joystick, SDL_CONTROLLER_AXIS_RIGHTY, axis);
-
axis = ((int)*(Sint16*)(&data[9]) * 64) - 32768;
if (axis == 32704) {
axis = 32767;
}
- SDL_PrivateJoystickAxis(joystick, SDL_CONTROLLER_AXIS_TRIGGERLEFT, axis);
+ SDL_PrivateJoystickAxis(joystick, SDL_CONTROLLER_AXIS_TRIGGERLEFT, FilterTrigger(axis));
axis = ((int)*(Sint16*)(&data[11]) * 64) - 32768;
if (axis == 32704) {
axis = 32767;
}
- SDL_PrivateJoystickAxis(joystick, SDL_CONTROLLER_AXIS_TRIGGERRIGHT, axis);
+ SDL_PrivateJoystickAxis(joystick, SDL_CONTROLLER_AXIS_TRIGGERRIGHT, FilterTrigger(axis));
+
+ axis = (int)*(Uint16*)(&data[1]) - 0x8000;
+ SDL_PrivateJoystickAxis(joystick, SDL_CONTROLLER_AXIS_LEFTX, FilterLeftThumb(axis));
+ axis = (int)*(Uint16*)(&data[3]) - 0x8000;
+ SDL_PrivateJoystickAxis(joystick, SDL_CONTROLLER_AXIS_LEFTY, FilterLeftThumb(axis));
+ axis = (int)*(Uint16*)(&data[5]) - 0x8000;
+ SDL_PrivateJoystickAxis(joystick, SDL_CONTROLLER_AXIS_RIGHTX, FilterRightThumb(axis));
+ axis = (int)*(Uint16*)(&data[7]) - 0x8000;
+ SDL_PrivateJoystickAxis(joystick, SDL_CONTROLLER_AXIS_RIGHTY, FilterRightThumb(axis));
SDL_memcpy(ctx->last_state, data, SDL_min(size, sizeof(ctx->last_state)));
}