Improve Analog Deadzone

Author: LRFLEW

desmume/src/frontend/windows/gbaslot_config.cpp

@@ -488,8 +488,6 @@ INT_PTR CALLBACK GbaSlotAnalog(HWND dialog, UINT msg, WPARAM wparam, LPARAM lpar
 		SendDlgItemMessage(dialog, IDC_ANALOG_DEADZONE_SLIDER, TBM_SETPOS, TRUE, tmp_Analog.Deadzone);
 
 		CheckDlgButton(dialog, IDC_ANALOG_JOINED, tmp_Analog.Joined);
-		CheckDlgButton(dialog, IDC_ANALOG_CIRCLE, tmp_Analog.Circle);
-		EnableWindow(GetDlgItem(dialog, IDC_ANALOG_CIRCLE), tmp_Analog.Joined);
 		return TRUE;
 	}
 
@@ -536,10 +534,7 @@ INT_PTR CALLBACK GbaSlotAnalog(HWND dialog, UINT msg, WPARAM wparam, LPARAM lpar
 			return TRUE;
 		}
 		case MAKELONG(IDC_ANALOG_JOINED, BN_CLICKED):
-		case MAKELONG(IDC_ANALOG_CIRCLE, BN_CLICKED):
 			tmp_Analog.Joined = IsDlgCheckboxChecked(dialog, IDC_ANALOG_JOINED);
-			tmp_Analog.Circle = IsDlgCheckboxChecked(dialog, IDC_ANALOG_CIRCLE);
-			EnableWindow(GetDlgItem(dialog, IDC_ANALOG_CIRCLE), tmp_Analog.Joined);
 			return TRUE;
 		}
 		return FALSE;
@@ -732,7 +727,6 @@ void GBAslotDialog(HWND hwnd)
 				WritePrivateProfileInt("Slot2.Analog", "Y", Analog.Y, IniName);
 				WritePrivateProfileInt("Slot2.Analog", "Deadzone", Analog.Deadzone, IniName);
 				WritePrivateProfileBool("Slot2.Analog", "Joined", Analog.Joined, IniName);
-				WritePrivateProfileBool("Slot2.Analog", "Circle", Analog.Circle, IniName);
 				break;
 			default:
 				return;

desmume/src/frontend/windows/inputdx.cpp

@@ -263,7 +263,7 @@ SPaddle Paddle;
 SPaddle DefaultPaddle = { false, 'K', 'L' };
 
 SAnalog Analog;
-SAnalog DefaultAnalog = { false, 1, 2, 15, true, true };
+SAnalog DefaultAnalog = { false, 1, 2, 15, true };
 
 bool killStylusTopScreen = false;
 bool killStylusOffScreen = false;
@@ -485,7 +485,6 @@ static void LoadAnalogConfig()
 	ReadAnalogControl("Y", Analog.Y);
 	ReadAnalogControl("Deadzone", Analog.Deadzone);
 	ReadAnalogBool("Joined", Analog.Joined);
-	ReadAnalogBool("Circle", Analog.Circle);
 }
 
 
@@ -2714,6 +2713,12 @@ static float get_analog_float(WORD axis)
 	return (float) val / 10000.0f;
 }
 
+static float apply_deadzone(float value, float mag, float deadzone) {
+	if (mag <= deadzone) return 0.0f;
+	float cmag = std::min(mag, 1.0f); // clamp mag to 1.0f just in case
+	return value * (cmag - deadzone) / (1.0f - deadzone) / mag;
+}
+
 //void S9xOldAutofireAndStuff ()
 //{
 //	// stuff ripped out of Snes9x that's no longer functional, at least for now
@@ -3058,11 +3063,13 @@ void input_acquire()
 			float y = get_analog_float(Analog.Y);
 
 			if (Analog.Joined) {
-				float value = Analog.Circle ? std::hypot(x, y) : (std::max)(std::abs(x), std::abs(y));
-				if (value < deadzone) x = y = 0.0f;
+				float mag = std::hypot(x, y);
+				x = apply_deadzone(x, mag, deadzone);
+				y = apply_deadzone(y, mag, deadzone);
 			} else {
-				if (x < deadzone && x > -deadzone) x = 0.0f;
-				if (y < deadzone && y > -deadzone) y = 0.0f;
+				// Faster approximation that prioritizes cardinal directions
+				x = apply_deadzone(x, x, deadzone);
+				y = apply_deadzone(y, y, deadzone);
 			}
 
 			analog_setValue(x, y);

desmume/src/frontend/windows/inputdx.h

@@ -167,7 +167,6 @@ struct SAnalog {
 
 	WORD Deadzone;
 	BOOL Joined;
-	BOOL Circle;
 };
 
 extern SGuitar Guitar;

desmume/src/frontend/windows/resource.h

@@ -527,7 +527,6 @@
 #define IDC_CHECK1                      1074
 #define IDC_CHECK2                      1075
 #define IDC_CAP0_SRC                    1075
-#define IDC_ANALOG_CIRCLE               1075
 #define IDC_CHECK3                      1076
 #define IDC_CAP0_ONESHOT                1076
 #define IDC_CHECK4                      1077

desmume/src/frontend/windows/resources.rc

@@ -1602,7 +1602,6 @@ BEGIN
     EDITTEXT        IDC_ANALOG_DEADZONE,105,41,40,14,ES_AUTOHSCROLL | ES_NUMBER
     RTEXT           "Deadzone",-1,61,41,38,14,SS_CENTERIMAGE
     CONTROL         "Joined Deadzone",IDC_ANALOG_JOINED,"Button",BS_AUTOCHECKBOX | WS_TABSTOP,66,63,71,10
-    CONTROL         "Circular Deadzone",IDC_ANALOG_CIRCLE,"Button",BS_AUTOCHECKBOX | WS_DISABLED | WS_TABSTOP,74,77,74,10
 END