RotaryVelocityTracker.kt
/*
* Copyright 2024 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package androidx.wear.compose.foundation.rotary
import androidx.compose.ui.input.pointer.util.VelocityTracker1D
/**
* A wrapper around VelocityTracker1D to provide support for rotary input.
*/
internal class RotaryVelocityTracker {
private var velocityTracker: VelocityTracker1D = VelocityTracker1D(true)
/**
* Retrieve the last computed velocity.
*/
val velocity: Float
get() = velocityTracker.calculateVelocity()
/**
* Start tracking motion.
*/
fun start(currentTime: Long) {
velocityTracker.resetTracking()
velocityTracker.addDataPoint(currentTime, 0f)
}
/**
* Continue tracking motion as the input rotates.
*/
fun move(currentTime: Long, delta: Float) {
velocityTracker.addDataPoint(currentTime, delta)
}
/**
* Stop tracking motion.
*/
fun end() {
velocityTracker.resetTracking()
}
}