CHANGE: ISX-2322 Rely on module (and platform) to manage polling frequency. (#2200)

Author: ekcoh

Assets/Tests/InputSystem/CoreTests_Devices.cs

@@ -4394,6 +4394,15 @@ public void Devices_CanSetPollingFrequency()
         Assert.That(InputSystem.pollingFrequency, Is.EqualTo(120).Within(0.000001));
     }
 
+    #if UNITY_INPUT_SYSTEM_PLATFORM_POLLING_FREQUENCY
+    [Test]
+    [Category("Devices")]
+    public void Devices_PollingFrequencyIsAtLeast60HzByDefault()
+    {
+        Assert.That(InputSystem.pollingFrequency, Is.GreaterThanOrEqualTo(60));
+    }
+
+    #else
     [Test]
     [Category("Devices")]
     public void Devices_PollingFrequencyIs60HzByDefault()
@@ -4403,6 +4412,8 @@ public void Devices_PollingFrequencyIs60HzByDefault()
         Assert.That(runtime.pollingFrequency, Is.EqualTo(60).Within(0.000001));
     }
 
+    #endif
+
     [Test]
     [Category("Devices")]
     public unsafe void Devices_CanInterceptAndHandleDeviceCommands()

Assets/Tests/InputSystem/Unity.InputSystem.Tests.asmdef

@@ -65,6 +65,11 @@
             "name": "Unity",
             "expression": "6000.0.15",
             "define": "UNITY_INPUT_SYSTEM_SENDPOINTERHOVERTOPARENT"
+        },
+        {
+            "name": "Unity",
+            "expression": "6000.3.0a6",
+            "define": "UNITY_INPUT_SYSTEM_PLATFORM_POLLING_FREQUENCY"
         }
     ],
     "noEngineReferences": false

Packages/com.unity.inputsystem/CHANGELOG.md

@@ -84,6 +84,7 @@ however, it has to be formatted properly to pass verification tests.
 ### Changed
 - Changed default input action asset name from New Controls to New Actions.
 - Added disabling of action maps in rebinding UI sample.
+- `InputSystem.pollingFrequency` is now initialized based on recommended polling frequency by the underlying platform on Unity versions newer than 6000.3.0a1. It can still be customized (set) during run-time as usual. Increasing polling frequency beyond the default 60Hz leads to less probability of input loss and reduces input latency.
 
 ### Added
 - An alternative way to access if an action state reached a certain phase during this rendering frame (Update()). This can be utilized even if the InputSystem update mode is set to manual or FixedUpdate. It can be used to access the action phase during rendering, eg for perform updates to the UI.

Packages/com.unity.inputsystem/InputSystem/InputManager.cs

@@ -197,16 +197,28 @@ public InputSettings.ScrollDeltaBehavior scrollDeltaBehavior
 
         public float pollingFrequency
         {
-            get => m_PollingFrequency;
+            get
+            {
+                #if UNITY_INPUT_SYSTEM_PLATFORM_POLLING_FREQUENCY
+                return m_Runtime.pollingFrequency;
+                #else
+                return m_PollingFrequency;
+                #endif
+            }
+
             set
             {
                 ////REVIEW: allow setting to zero to turn off polling altogether?
                 if (value <= 0)
                     throw new ArgumentException("Polling frequency must be greater than zero", "value");
 
+                #if UNITY_INPUT_SYSTEM_PLATFORM_POLLING_FREQUENCY
+                m_Runtime.pollingFrequency = value;
+                #else
                 m_PollingFrequency = value;
                 if (m_Runtime != null)
                     m_Runtime.pollingFrequency = value;
+                #endif
             }
         }
 
@@ -1888,8 +1900,10 @@ internal void InitializeData()
 
             m_ScrollDeltaBehavior = InputSettings.ScrollDeltaBehavior.UniformAcrossAllPlatforms;
 
+            #if !UNITY_INPUT_SYSTEM_PLATFORM_POLLING_FREQUENCY
             // Default polling frequency is 60 Hz.
             m_PollingFrequency = 60;
+            #endif
 
             // Register layouts.
             // NOTE: Base layouts must be registered before their derived layouts
@@ -2141,7 +2155,9 @@ internal struct AvailableDevice
 
         // Used by EditorInputControlLayoutCache to determine whether its state is outdated.
         internal int m_LayoutRegistrationVersion;
+        #if !UNITY_INPUT_SYSTEM_PLATFORM_POLLING_FREQUENCY
         private float m_PollingFrequency;
+        #endif
 
         internal InputControlLayout.Collection m_Layouts;
         private TypeTable m_Processors;
@@ -4092,7 +4108,9 @@ internal SerializedState SaveState()
             return new SerializedState
             {
                 layoutRegistrationVersion = m_LayoutRegistrationVersion,
+                #if !UNITY_INPUT_SYSTEM_PLATFORM_POLLING_FREQUENCY
                 pollingFrequency = m_PollingFrequency,
+                #endif
                 devices = deviceArray,
                 availableDevices = m_AvailableDevices?.Take(m_AvailableDeviceCount).ToArray(),
                 buffers = m_StateBuffers,
@@ -4118,7 +4136,9 @@ internal void RestoreStateWithoutDevices(SerializedState state)
             updateMask = state.updateMask;
             scrollDeltaBehavior = state.scrollDeltaBehavior;
             m_Metrics = state.metrics;
+            #if !UNITY_INPUT_SYSTEM_PLATFORM_POLLING_FREQUENCY
             m_PollingFrequency = state.pollingFrequency;
+            #endif
 
             if (m_Settings != null)
                 Object.DestroyImmediate(m_Settings);

Packages/com.unity.inputsystem/InputSystem/InputSystem.cs

@@ -1364,7 +1364,7 @@ public static event InputDeviceFindControlLayoutDelegate onFindLayoutForDevice
         /// The unit is Hertz. A value of 120, for example, means that devices are sampled 120 times
         /// per second.
         ///
-        /// The default polling frequency is 60 Hz.
+        /// The default polling frequency is at least 60 Hz or what is suitable for the target device.
         ///
         /// For devices that are polled, the frequency setting will directly translate to changes in the
         /// <see cref="InputEvent.time"/> patterns. At 60 Hz, for example, timestamps for a specific,

Packages/com.unity.inputsystem/InputSystem/NativeInputRuntime.cs

@@ -211,10 +211,16 @@ public Action<bool> onPlayerFocusChanged
 
         public float pollingFrequency
         {
+            #if UNITY_INPUT_SYSTEM_PLATFORM_POLLING_FREQUENCY
+            get => NativeInputSystem.GetPollingFrequency();
+            #else
             get => m_PollingFrequency;
+            #endif
             set
             {
+                #if !UNITY_INPUT_SYSTEM_PLATFORM_POLLING_FREQUENCY
                 m_PollingFrequency = value;
+                #endif
                 NativeInputSystem.SetPollingFrequency(value);
             }
         }
@@ -246,7 +252,12 @@ public bool runInBackground
         #if UNITY_EDITOR
         private Action m_PlayerLoopInitialization;
         #endif
+        #if !UNITY_INPUT_SYSTEM_PLATFORM_POLLING_FREQUENCY
+        // From Unity 6000.3.0a2 (TODO Update comment and manifest before landing PR) this is handled by module
+        // and initial value is suggested by the platform based on its supported device set.
+        // In older version this is stored here and package override module/platform.
         private float m_PollingFrequency = 60.0f;
+        #endif
         private bool m_DidCallOnShutdown = false;
         private void OnShutdown()
         {

Packages/com.unity.inputsystem/InputSystem/Unity.InputSystem.asmdef

@@ -111,6 +111,11 @@
             "name": "com.unity.modules.unityanalytics",
             "expression": "1",
             "define": "UNITY_INPUT_SYSTEM_ENABLE_ANALYTICS"
+        },
+        {
+            "name": "Unity",
+            "expression": "6000.3.0a6",
+            "define": "UNITY_INPUT_SYSTEM_PLATFORM_POLLING_FREQUENCY"
         }
     ],
     "noEngineReferences": false

Packages/com.unity.inputsystem/Tests/TestFixture/InputTestRuntime.cs

@@ -359,7 +359,7 @@ public struct PairedUser
         public Action onShutdown { get; set; }
         public Action<bool> onPlayerFocusChanged { get; set; }
         public bool isPlayerFocused => m_HasFocus;
-        public float pollingFrequency { get; set; }
+        public float pollingFrequency { get; set; } = 60.0f; // At least 60 Hz by default
         public double currentTime { get; set; }
         public double currentTimeForFixedUpdate { get; set; }
         public float unscaledGameTime { get; set; } = 1;