How to get the passed value?

Tell me how to make such a condition.

I need to get every pixel passed by the player. That is, if a player has move 100 pixels, I want to add 100 pixels to the variable.

that is, I need to get the distance traveled by the player. How can I do that?

In fact, I need to take away a strip of fuel when the car goes.

You calculate distance from the start point to the player and that's the distance travelled in pixels : distance(start.x,start.y,player.x,player.y) assuming you are just moving in one direction, you didn't give any info about the game.

WRS

instead of using the start x and y in the distance calculation, use the Last x and y (and the current x,y). Every time you check the distance traveled, update the Last x and y.

distance(lastX,lastY,player.x,player.y)

lastX = player.x

lastY = player.y