The distance from the sprite to the sprite is 0, it is at the same position of “itself”
If you are trying to measure the distance toward some other point you can use Vector’s distance_to function
global_position.distance_to(other_object.global_position)
If this script is attached to the sprite then using position or self.position will get the position, like you’ve used before in calculating mouse_offset
mouse_offset = event.position - position
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