ドラッグで要素を動かす

<img id="dragimg" src="./sample.png">

<script>
dragimg.onpointermove = function(event){
    if(event.buttons){
        this.style.left     = this.offsetLeft + event.movementX + 'px'
        this.style.top      = this.offsetTop  + event.movementY + 'px'
        this.style.position = 'absolute'
        this.draggable      = false
        this.setPointerCapture(event.pointerId)
    }
}
</script>