1.12.2 How to make a plugin that counts walkes rounds

Are you sure the example you showed us isn't just counting the blocks travelled in general. If that's not the case I can think of many reasons on how to track blocks of a player running around a circle.

The first idea that comes to my mind is making hidden waypoints and then calculating the blocks travelled from the last waypoint.

 

Here is how I would perhaps do it:

For simplicity imagine your spawn being at (0,0). You will have a north-south and east-west axis. The signs of the coordinates in each quadrant are:
north-east: (+,-)
south-east: (+,+)
south-west: (-,+)
north-west: (-,-)

Create an enum for each side: NORTH, EAST, SOUTH, WEST.

Define the radius of your spawn which is the minimum distance that a player has to be away from the center for a lap to count. Also define its square:

Code (Text):

int radius = 10;
int radiusSquared = radius * radius;

Listen to PlayerMoveEvent and compare the signs for x and z of .from() and .to(). For example if the signs changed from (+,-) to (+,+) you know that the player just crossed the east-west axis on the east side.
If the crossing happend while

Code (Text):

player.getLocation().distanceSquared(spawn) > radiusSquared

was true, map the enum corresponding to the crossing to the player:

Code (Text):

Map<Player, Side> latestSideCrossed = new HashMap<>();
latestSideCrossed.put(player, Side.EAST);

Now start two quadrant counters (clockwise and anti-clockwise). If the next crossing happens on the south/north side increase the corresponding counter by 1 and reset the other one. Also update the enum value in the HashMap. Once a counter hits 4 a lap just happened.

 

I also want to know about that. I am going to share this question https://www.spigotmc.org/threads/how-to-make-a-plugin-619 area code-that-counts-walkes-rounds.557083/#post-4411008 with my friends and brother. Hope so, he knows something about this.

Please wait for my next reply with good answer as soon as possible.