◒ courtside.
THE RALLY STUDIO
RALLY SIMULATOR 06 / ACCURACY. MOVEMENT. FLOW.

Choose the shot. Prepare the return.

START WITH
Baseline exchangeHARD COURT
AReady0.0 m/s
0SHOTS·0.00SEC
0.0 m/sReceivingB
PLAYER A · CONTACT
Solid trace: played flight · dotted trace: next incident preview
BALL 0 km/h
Player A Player B
Ready to start
Pick a landingSimulated legal landing samples
Estimated spread
1 · CHOOSE A BALL PATH

Click a coloured trajectory, then place the opponent.

0.00 / 0.00 s
OPPONENT PREPARATIONChoose a shot
Settled at destination in—
Ball contact in—
Preparation window—

↗
BEFORE THE OPENING HIT

Player A is ready.

Set each player's attributes and return. Then play the first shot.

The point flows continuously. Use Pause & direct to change it at any moment.
AT THE CONTACT

Choose Player A’s ball.

——

▰ Estimated range● Actual launch○ Requested
PREVIEW THIS SHOT——
First bounce
—
At the net
—

Flight preview assumes no opponent return.

THE RALLY TIMELINE

Pick a moment. Try another way.

ORIGINAL CASE

Select any incident to rewind. Edit a setting to replace only the future. Pin the current case first to keep a comparison.

A

Player A

NEAR COURT
Height / arm—
Mass—
Power / speed—
Distance run 0.0 mAcceleration —
Time getting set—
B

Player B

FAR COURT
Height / arm—
Mass—
Power / speed—
Distance run 0.0 mAcceleration —
Time getting set—
THE WHOLE POINT

A flight with many chapters.

HEIGHT / TIME
Ball heightDots mark hits and bounces
INTERVENE AT THIS MOMENT

Choose the opening shot.

⑂

Player settings affect future movement; each player's shot settings apply when they next hit.

Next incidentCalculating…Projected time—
SAVE THE PATH YOU DIDN’T TAKE

Pin this rally, rewind, then change an input to compare outcomes.

KEEP THIS BRANCH

Save your rally case.

The incident history, both player profiles and current position will be saved so you can resume later.
HOW THE RALLY WORKS

Two players. One continuous point.

This is an illustrative practice-rally model. It starts with a groundstroke from Player A and estimates how shot selection, movement and preparation interact. It does not model serves or scoring games.

Choose a landing, then plan the return

The court map samples hundreds of simulated flights across different pace and spin settings, showing only legal landings. It is a finite sample, not a guarantee that every gap is reachable. Choose Pick landing and click a point, or use the Landing controls for 5 cm adjustments. Topspin, flat, slice, lob, drop shot and sidespin are starting styles; RPM remains adjustable. The inverse planner holds requested pace and spin fixed while solving direction and elevation, checks the net and court, and reports actual landing error. An unreachable target keeps its nearest simulated alternative visible.

After placing the receiver, Return switches to the predicted racket contact, including incoming velocity, body position, preparation and movement. Its landing map and trajectories use that state. Editing the return preserves the incoming ball and timeline. Move the receiver again to recalculate feasibility; a missed ball has no return preview. Planned landing intent is saved and re-solved at the actual contact. The timing panel continues to describe the incoming ball.

Guidance paths on the court

At every contact, six coloured previews show the current stroke and alternative left/right topspin, deep, slice and lob shots. Click a path, its numbered marker or its matching button, then click the receiver’s half to set a destination. The selected shot uses exactly the previewed inputs. Risky paths remain labelled with their simulated net or out result.

The timing panel reports settled arrival, actual next contact and the preparation window after movement and reaction. A bounce is not the contact deadline. Rushed or missed returns are shown explicitly. Earlier preparation may carry forward; pausing the screen adds no preparation time.

Accuracy around the aim

The pale shaded area and dots show variation around the physical shot. Skill, preparation, running speed and stretched contact change small launch-direction, elevation, pace and spin errors. Each sample follows the same flight physics, including net and out outcomes. The area follows the modeled landing distribution, so a biased or unreachable target is not falsely made accurate. Net samples have no invented landing behind the net. The displayed fractions are weighted model samples, not measured probabilities; the spread coefficients are illustrative. Playback uses the nominal shot, so replay stays deterministic. Disable Accuracy area to hide it, or Apply ability & preparation for unrestricted physics.

Continuous scenes

Continuous rally is the default flow. Bounces and alternating contacts retain their exact physical state and unused frame time. A fixed court view prevents zoom jumps, while body gait follows distance traveled. Use Flow beside Play to pause at every return or incident. Pause & direct still makes a checkpoint at the displayed moment. Shot maps are rebuilt when editing, not between continuous scenes.

Contact, choice, movement, preparation

At each hit, the shaded map shows an estimated direction and elevation range. Height and arm length affect reach; stroke skill, swing ability, running speed and preparation affect available power, angles and spin. Choose a suggested stroke or edit its angles and spin. The actual launch and projected landing update before you play.

The range is a scenario heuristic, not a measured biomechanical limit. Time spent settled at low speed builds preparation, up to the athlete’s selected time to get set. Running reduces readiness. A rushed stroke loses a proportion of pace and spin, and its angle range narrows. The accuracy overlay estimates execution dispersion separately; neither the capability map nor the spread promises a legal landing.

Three ways to create a stroke

Target assist solves for a launch angle toward a chosen landing point. Ball launch holds your requested speed, elevation, direction and spin, so the landing follows the physics. Swing impact estimates the result from incoming ball velocity and spin, racket speed, effort, swing path, face angles, contact quality, string grip and rebound. The moving-racket collision is simplified; it omits detailed racket recoil, string snapback and biomechanics. Ability limits are applied once after resolving the requested stroke.

Tell each player where to go

Movement can automatically seek a contact, or follow your chosen court destination. Manual movement respects reaction delay, acceleration and top speed. Use the Movement tab to place a destination or use the projected contact shortcut. The player gets set as they settle; the ball can pass out of reach while they wait. Pausing the interface adds no simulation time or preparation.

Intervene during flight

Pause & direct creates a new checkpoint at the displayed moment. Ball position, velocity and spin, body velocity, preparation and elapsed reaction time carry forward. Edit movement and continue. A return incident pauses before the outgoing stroke. Rewinding and editing replaces only the future; saved cases retain decision checkpoints and pinned cases keep a comparison.

Continuous physics

The ball uses gravity, air resistance, spin lift, wind and tangential bounce impulses. Body mass affects acceleration through force ÷ mass. Body size does not independently determine stroke power. The opening stroke has its own preparation setting, and both players have separate ability, movement and stroke controls.

Point endings

The point ends on a net collision, an out first bounce or a second bounce before a return. A shot limit is a simulation pause, not a winner. Net-cord collisions end the point in this simplified model; legal cord deflections are not simulated. Court friction and restitution are fixed by surface, without detailed grip/slip bounce or elastic deformation. The court and ball use ITF dimensions; aerodynamic and court coefficients are illustrative. This is a tool for exploring scenarios rather than calibrated athlete prediction.

ITF 2026 rules ↗ · Measured tennis aerodynamics ↗ · NASA spin and aerodynamic forces ↗ · Cross: ball–string friction ↗ · Stroke biomechanics context ↗