David M. said: Following up on Gauss' comment, Freehand paths are really just composed of a ton of line segments so close together that they appear smooth from the zoom level of the vtt. Ray tracing calculations for line of sight have to be performed for each line segment on the map every time a token is moved, which takes processor time and causes the high resource usage Gauss mentioned. Due to the unpredictable placement of joins, you could also occasionally wind up with extremely sharp angles, which due to the mathematics of the process could project "phantom barriers". This can still happen with the pen tool, AFAIK, but it's not something a person would usually draw.