clicked(event) {
		// Check if left mouse button is pressed
		if (event.button === 0 && this.isClickable) {
			this.isDirty = true;
			this.released = false;
			if (this.isHoldable) {
				timer.clearTimer(this.holdTimeout);
				this.holdTimeout = timer.setTimeout(
					() => {
						return this.hold();
					},
					this.holdThreshold,
					false,
				);
				this.released = false;
			}
			if (this.isDraggable) {
				this.grabOffset.set(event.gameX, event.gameY);
				this.grabOffset.sub(this.pos);
			}
			return this.onClick(event);
		}
	}
function callback for the pointerdown event
@ignore