movementAnimator.kt

fun movementAnimator(marker: Marker, newLatLng: LatLng) : ValueAnimator {
    val animator = ValueAnimator.ofFloat(0f, 100f)

    val deltaLatitude = doubleArrayOf(newLatLng.latitude - marker.position.latitude)
    val deltaLongitude = newLatLng.longitude - marker.position.longitude
    val prevStep = floatArrayOf(0f)
    animator.duration = 1500

    animator.addUpdateListener { animation ->
        val deltaStep = (animation.animatedValue as Float - prevStep[0]).toDouble()
        prevStep[0] = animation.animatedValue as Float
        val latLng = LatLng(
            marker.position.latitude + deltaLatitude[0] * deltaStep * 1.0 / 100,
            marker.position.longitude + deltaStep * deltaLongitude * 1.0 / 100
        )
        marker.position = latLng
    }
    return animator
}