"Tennis For One" is an action-packed solo version of the arcade hit "Tennis For Two."
"Tennis For One" is played on a single screen. The player controls the vertical position of a racket using their mouse, and uses it to bounce a ball into a target area.
Every round, the ball starts in the middle of the screen and -- after the user clicks -- is launched to the right with a random vertical velocity. The ball moves in a straight line, bouncing off of the top and bottom walls.
If the ball hits the racket, it is bounced back into the field with a new velocity (depending on its position relative to the center of the racket). If the ball reaches the right wall, it is reset to the center of the field and launched when the user clicks. If the ball reaches the right wall three times, the game ends, and the score is displayed.
If the ball hits the target, the player is awarded a point and a new rounds starts. If the ball reaches the left wall, it bounces off, and the round continues.
The vertical velocity of the ball leaving the paddle is set by its position of impact relative to the center of the paddle. This allows the player to steer the ball.
Every round, the target is placed at a random vertical position. The size of the target decreases every round.