Remove applyVelocityPolicyTo(), Replace System.nanoTime with Timesource, Replace allowVelocity with hasVelocity in ProtobufBridge.

Author: M1DNYT3

server/core/src/main/java/dev/slimevr/VRServer.kt

@@ -186,21 +186,6 @@ class VRServer @JvmOverloads constructor(
 		instance = this
 	}
 
-	/**
-	 * TODO: The design of this method is chosen for future expandability in case we want to have more complex velocity policies that depend on tracker properties or other config values.
-	 * Initiates the velocity policy application process for the specified [Tracker] (or all trackers if null).
-	 *
-	 * This method serves as the initiator.
-	 * The actual policy logic is not handled here,
-	 * but is delegated to [dev.slimevr.config.VRConfig.applyVelocityPolicy].
-	 */
-	private fun applyVelocityPolicyTo(tracker: Tracker?) {
-		val targets = tracker?.let { listOf(it) } ?: trackers
-		for (t in targets) {
-			configManager.vrConfig.applyVelocityPolicy(t)
-		}
-	}
-
 	fun hasBridge(bridgeClass: Class<out Bridge?>): Boolean {
 		for (bridge in bridges) {
 			if (bridgeClass.isAssignableFrom(bridge.javaClass)) {
@@ -247,7 +232,7 @@ class VRServer @JvmOverloads constructor(
 			configManager.saveConfig()
 
 			// Requires a fresh TrackerConfig on Update, so executed after we save a new state.
-			applyVelocityPolicyTo(tracker)
+			tracker?.let { configManager.vrConfig.applyVelocityPolicy(it) }
 		}
 	}
 

server/core/src/main/java/dev/slimevr/tracking/processor/skeleton/HumanSkeleton.kt

@@ -1171,7 +1171,7 @@ class HumanSkeleton(
 			it.position = trackerBone.getTailPosition()
 			it.setRotation(trackerBone.getGlobalRotation() * trackerBone.rotationOffset.inv())
 			it.dataTick()
-			it.updateDerivedVelocity(System.nanoTime())
+			it.updateDerivedVelocity()
 		}
 	}
 

server/core/src/main/java/dev/slimevr/tracking/trackers/Tracker.kt

@@ -12,6 +12,9 @@ import io.eiren.util.BufferedTimer
 import io.github.axisangles.ktmath.Quaternion
 import io.github.axisangles.ktmath.Vector3
 import kotlin.properties.Delegates
+import kotlin.time.DurationUnit
+import kotlin.time.TimeMark
+import kotlin.time.TimeSource
 
 const val TIMEOUT_MS = 2_000L
 const val DISCONNECT_MS = 3_000L + TIMEOUT_MS
@@ -123,7 +126,7 @@ class Tracker @JvmOverloads constructor(
 	 * Velocity state server-side differentiation based on sent poses
 	 */
 	private data class VelocityState(
-		var prevTimeNs: Long = 0L,
+		var prevMark: TimeMark? = null,
 		var prevPos: Vector3 = Vector3(0f, 0f, 0f),
 	)
 
@@ -370,7 +373,7 @@ class Tracker @JvmOverloads constructor(
 	 * last update, applying a sanity check on the time delta to filter out noise and ensure data stability.
 	 *
 	 */
-	fun updateDerivedVelocity(nowNs: Long) {
+	fun updateDerivedVelocity() {
 		if (!allowVelocity || !hasPosition) {
 			velocityState = null
 			_velocity = Vector3.NULL
@@ -382,8 +385,9 @@ class Tracker @JvmOverloads constructor(
 			velocityState = it
 		}
 
-		if (state.prevTimeNs != 0L) {
-			val dt = (nowNs - state.prevTimeNs) * 1e-9
+		val prevMark = state.prevMark
+		if (prevMark != null) {
+			val dt = prevMark.elapsedNow().toDouble(DurationUnit.SECONDS)
 			if (dt in 1e-4..0.25) {
 				_velocity = Vector3(
 					((pos.x - state.prevPos.x) / dt).toFloat(),
@@ -394,7 +398,7 @@ class Tracker @JvmOverloads constructor(
 				_velocity = Vector3.NULL
 			}
 		}
-		state.prevTimeNs = nowNs
+		state.prevMark = TimeSource.Monotonic.markNow()
 		state.prevPos = pos
 	}
 

server/desktop/src/main/java/dev/slimevr/desktop/platform/ProtobufBridge.kt

@@ -124,7 +124,7 @@ abstract class ProtobufBridge(@JvmField protected val bridgeName: String) : ISte
 			builder.setQw(rot.w)
 		}
 
-		if (tracker.allowVelocity) {
+		if (tracker.hasVelocity) {
 			val vel = tracker.getVelocity()
 			builder.setVx(vel.x)
 			builder.setVy(vel.y)