When testing map or modding a map it is hard to show the creator exactly how you played the map unless you go on an image editing software and create a flow-chart of how you played the map (which is not entirely accurate).
This feature "saves" the cursor movement from the last F5 test as an invisible smoke that can be toggled on/off and when on, shows the recent cursor movement around that part of the map, just before or after the current timestamp.
Example:
The amount you want to see ahead and before the timestamp you are on should be customisable, but if not then it should scale with AR.
In my example I just shown the smoke ahead, and it made it pretty clear to me that the snap at the bottom is a bit harsh and could cause a sliderbreak with slider 4, so this kind of feature is mostly for modding/personal mapping, but should clear up a lot of misconceptions about playability of patterns as least for certain skill levels of players. Not only spotting hard to play patterns but also fine tuning existing patterns should all be easier if the last play is easily visible.
Also, as a bonus point, it makes the F5 testplay option more useful because not that many mappers actually use it, they play the maps normally to account for drain.
tl;dr of tl;dr
It creates a flowchart based on your recent test of the map that you can toggle.
This feature "saves" the cursor movement from the last F5 test as an invisible smoke that can be toggled on/off and when on, shows the recent cursor movement around that part of the map, just before or after the current timestamp.
Example:
The amount you want to see ahead and before the timestamp you are on should be customisable, but if not then it should scale with AR.
In my example I just shown the smoke ahead, and it made it pretty clear to me that the snap at the bottom is a bit harsh and could cause a sliderbreak with slider 4, so this kind of feature is mostly for modding/personal mapping, but should clear up a lot of misconceptions about playability of patterns as least for certain skill levels of players. Not only spotting hard to play patterns but also fine tuning existing patterns should all be easier if the last play is easily visible.
Also, as a bonus point, it makes the F5 testplay option more useful because not that many mappers actually use it, they play the maps normally to account for drain.
tl;dr of tl;dr
It creates a flowchart based on your recent test of the map that you can toggle.