Gyro tightening

A practical way to avoid a noisy gyro signal, or shaky hands.
Unlike a deadzone, inputs below the threshold are "squeezed towards
zero", so they are not completely ignored. Source:
http://gyrowiki.jibbsmart.com/blog:good-gyro-controls-part-1:the-gyro-is-a-mouse#toc9

doc/040_cvarlist.md

@@ -598,6 +598,10 @@ Set `0` by default.
   for people who hold the controller upright, or use a device with the
   controller attached to the screen, e.g. Steam Deck.
 
+* **gyro_tightening**: Threshold of rotation in degrees per second,
+  where gyro inputs below it will be dampened. Meant to counter a
+  noisy gyro and involuntary hand movements. Default `3.5`.
+
 * **gyro_calibration_(x/y/z)**: Offset values on each axis of the gyro
   which helps it reach true "zero movement", complete stillness. These
   values are wrong if you see your in-game view "drift" when leaving

src/client/input/sdl2.c

@@ -162,6 +162,7 @@ cvar_t *gyro_turning_axis;	// yaw or roll
 // Gyro sensitivity
 static cvar_t *gyro_yawsensitivity;
 static cvar_t *gyro_pitchsensitivity;
+static cvar_t *gyro_tightening;
 
 // Gyro is being used in this very moment
 static qboolean gyro_active = false;
@@ -1069,6 +1070,30 @@ IN_ApplyExpo(thumbstick_t stick, float exponent)
 	return result;
 }
 
+/*
+ * Minimize gyro movement when under a small threshold.
+ * http://gyrowiki.jibbsmart.com/blog:good-gyro-controls-part-1:the-gyro-is-a-mouse#toc9
+ */
+static thumbstick_t
+IN_TightenInput(float yaw, float pitch)
+{
+	thumbstick_t input = { yaw, pitch };
+	const float magnitude = IN_StickMagnitude(input);
+#ifdef NATIVE_SDL_GYRO
+	const float threshold = (M_PI / 180.0f) * gyro_tightening->value;
+#else
+	const float threshold = (2560.0f / 180.0f) * gyro_tightening->value;
+#endif
+
+	if (magnitude < threshold)
+	{
+		const float scale = magnitude / threshold;
+		input.x *= scale;
+		input.y *= scale;
+	}
+	return input;
+}
+
 /*
  * Delete flick stick's buffer of angle samples for smoothing
  */
@@ -1198,6 +1223,7 @@ IN_Move(usercmd_t *cmd)
 	static float joystick_yaw, joystick_pitch;
 	static float joystick_forwardmove, joystick_sidemove;
 	static thumbstick_t left_stick = {0}, right_stick = {0};
+	thumbstick_t gyro_in = {0};
 
 	if (m_filter->value)
 	{
@@ -1378,16 +1404,21 @@ IN_Move(usercmd_t *cmd)
 					* cl_sidespeed->value * 2.0f * joystick_sidemove;
 	}
 
-	if (gyro_yaw)
+	if (gyro_yaw || gyro_pitch)
 	{
-		cl.viewangles[YAW] += m_yaw->value * gyro_yawsensitivity->value
+		gyro_in = IN_TightenInput(gyro_yaw, gyro_pitch);
-					* cl_yawspeed->value * gyro_yaw * gyroViewFactor;
 	}
 
-	if (gyro_pitch)
+	if (gyro_in.x)
+	{
+		cl.viewangles[YAW] += m_yaw->value * gyro_yawsensitivity->value
+					* cl_yawspeed->value * gyro_in.x * gyroViewFactor;
+	}
+
+	if (gyro_in.y)
 	{
 		cl.viewangles[PITCH] -= m_pitch->value * gyro_pitchsensitivity->value
-					* cl_pitchspeed->value * gyro_pitch * gyroViewFactor;
+					* cl_pitchspeed->value * gyro_in.y * gyroViewFactor;
 	}
 
 	// Flick Stick: flick in progress, changing the yaw angle to the target progressively
@@ -2286,6 +2317,7 @@ IN_Init(void)
 
 	gyro_yawsensitivity = Cvar_Get("gyro_yawsensitivity", "1.0", CVAR_ARCHIVE);
 	gyro_pitchsensitivity = Cvar_Get("gyro_pitchsensitivity", "1.0", CVAR_ARCHIVE);
+	gyro_tightening = Cvar_Get("gyro_tightening", "3.5", CVAR_ARCHIVE);
 	gyro_turning_axis = Cvar_Get("gyro_turning_axis", "0", CVAR_ARCHIVE);
 
 	gyro_mode = Cvar_Get("gyro_mode", "2", CVAR_ARCHIVE);

src/client/input/sdl3.c

@@ -165,6 +165,7 @@ cvar_t *gyro_turning_axis;	// yaw or roll
 // Gyro sensitivity
 static cvar_t *gyro_yawsensitivity;
 static cvar_t *gyro_pitchsensitivity;
+static cvar_t *gyro_tightening;
 
 // Gyro is being used in this very moment
 static qboolean gyro_active = false;
@@ -1058,6 +1059,26 @@ IN_ApplyExpo(thumbstick_t stick, float exponent)
 	return result;
 }
 
+/*
+ * Minimize gyro movement when under a small threshold.
+ * http://gyrowiki.jibbsmart.com/blog:good-gyro-controls-part-1:the-gyro-is-a-mouse#toc9
+ */
+static thumbstick_t
+IN_TightenInput(float yaw, float pitch)
+{
+	thumbstick_t input = { yaw, pitch };
+	const float magnitude = IN_StickMagnitude(input);
+	const float threshold = (M_PI / 180.0f) * gyro_tightening->value;
+
+	if (magnitude < threshold)
+	{
+		const float scale = magnitude / threshold;
+		input.x *= scale;
+		input.y *= scale;
+	}
+	return input;
+}
+
 /*
  * Delete flick stick's buffer of angle samples for smoothing
  */
@@ -1187,6 +1208,7 @@ IN_Move(usercmd_t *cmd)
 	static float joystick_yaw, joystick_pitch;
 	static float joystick_forwardmove, joystick_sidemove;
 	static thumbstick_t left_stick = {0}, right_stick = {0};
+	thumbstick_t gyro_in = {0};
 
 	if (m_filter->value)
 	{
@@ -1367,16 +1389,21 @@ IN_Move(usercmd_t *cmd)
 					* cl_sidespeed->value * 2.0f * joystick_sidemove;
 	}
 
-	if (gyro_yaw)
+	if (gyro_yaw || gyro_pitch)
 	{
-		cl.viewangles[YAW] += m_yaw->value * gyro_yawsensitivity->value
+		gyro_in = IN_TightenInput(gyro_yaw, gyro_pitch);
-					* cl_yawspeed->value * gyro_yaw * gyroViewFactor;
 	}
 
-	if (gyro_pitch)
+	if (gyro_in.x)
+	{
+		cl.viewangles[YAW] += m_yaw->value * gyro_yawsensitivity->value
+					* cl_yawspeed->value * gyro_in.x * gyroViewFactor;
+	}
+
+	if (gyro_in.y)
 	{
 		cl.viewangles[PITCH] -= m_pitch->value * gyro_pitchsensitivity->value
-					* cl_pitchspeed->value * gyro_pitch * gyroViewFactor;
+					* cl_pitchspeed->value * gyro_in.y * gyroViewFactor;
 	}
 
 	// Flick Stick: flick in progress, changing the yaw angle to the target progressively
@@ -2278,6 +2305,7 @@ IN_Init(void)
 
 	gyro_yawsensitivity = Cvar_Get("gyro_yawsensitivity", "1.0", CVAR_ARCHIVE);
 	gyro_pitchsensitivity = Cvar_Get("gyro_pitchsensitivity", "1.0", CVAR_ARCHIVE);
+	gyro_tightening = Cvar_Get("gyro_tightening", "3.5", CVAR_ARCHIVE);
 	gyro_turning_axis = Cvar_Get("gyro_turning_axis", "0", CVAR_ARCHIVE);
 
 	gyro_mode = Cvar_Get("gyro_mode", "2", CVAR_ARCHIVE);

src/client/menu/menu.c

@@ -1780,6 +1780,7 @@ static menuslider_s s_gyro_yawsensitivity_slider;
 static menuslider_s s_gyro_pitchsensitivity_slider;
 static menulist_s s_gyro_invertyaw_box;
 static menulist_s s_gyro_invertpitch_box;
+static menuslider_s s_gyro_tightening_slider;
 static menuseparator_s s_calibrating_text[2];
 static menuaction_s s_calibrate_gyro;
 
@@ -1917,6 +1918,15 @@ Gyro_MenuInit(void)
 	s_gyro_invertpitch_box.itemnames = yesno_names;
 	s_gyro_invertpitch_box.curvalue = (Cvar_VariableValue("gyro_pitchsensitivity") < 0);
 
+	s_gyro_tightening_slider.generic.type = MTYPE_SLIDER;
+	s_gyro_tightening_slider.generic.x = 0;
+	s_gyro_tightening_slider.generic.y = (y += 20);
+	s_gyro_tightening_slider.generic.name = "tightening thresh";
+	s_gyro_tightening_slider.cvar = "gyro_tightening";
+	s_gyro_tightening_slider.minvalue = 0.0f;
+	s_gyro_tightening_slider.maxvalue = 12.0f;
+	s_gyro_tightening_slider.slidestep = 0.5f;
+
 	s_calibrating_text[0].generic.type = MTYPE_SEPARATOR;
 	s_calibrating_text[0].generic.x = 48 * scale + 32;
 	s_calibrating_text[0].generic.y = (y += 20);
@@ -1939,6 +1949,7 @@ Gyro_MenuInit(void)
 	Menu_AddItem(&s_gyro_menu, (void *)&s_gyro_pitchsensitivity_slider);
 	Menu_AddItem(&s_gyro_menu, (void *)&s_gyro_invertyaw_box);
 	Menu_AddItem(&s_gyro_menu, (void *)&s_gyro_invertpitch_box);
+	Menu_AddItem(&s_gyro_menu, (void *)&s_gyro_tightening_slider);
 	Menu_AddItem(&s_gyro_menu, (void *)&s_calibrating_text[0]);
 	Menu_AddItem(&s_gyro_menu, (void *)&s_calibrating_text[1]);
 	Menu_AddItem(&s_gyro_menu, (void *)&s_calibrate_gyro);