Basketball Legends
A free, open-source 3D basketball game that runs in the browser. Play pro basketball, 1,092 college programs, or every Arizona high school, then build a career from freshman year to the Hall of Fame or run a franchise.
Play it: https://legends.carterscoding.com
What's in the game
- Real-time 3D 5v5 with dribble moves, a timing-based shot meter, layups, dunks, floaters, post moves, alley-oops, steals, blocks and box-out rebounding.
- Full rules for each league: shot clocks, fouls and the bonus, free throws, inbounds, traveling, three seconds, backcourt and 8/10-second violations, goaltending, timeouts, substitutions, fatigue and overtime.
- Tested: unit tests for the engine (rules, injuries, saves, input), a camera sweep that flies every camera through every venue's real geometry and fails if one clips anything, and browser smoke tests for every page and the main game flows run on every deploy.
- Coaching: set each team's pace, three-point emphasis, offensive rebounding, double teams and defense (man-to-man, 2-3 zone, 3-2 zone or a full-court trapping press) before the game or from the pause menu.
- Gameplay sliders: shot, three-point and layup success, pass accuracy, steals, blocks, fouls, game speed, injuries and CPU aggression.
- Team AI that spaces the floor, runs pick-and-roll, drives and kicks, posts up, cuts, and plays man or zone defense with help rotations.
- Quick Play: any two teams from any league (cross-league exhibitions included), instant simulation, and up to four local players with keyboard and gamepads.
- Tutorial: a ten-step guided session (moving, sprinting, dribble moves, shot timing, layups, threes, passing, pump fakes, replays) that checks off each skill as you do it, using your own key and button bindings.
- Practice: a shootaround with no clock or defense.
- Play in the Park: pickup basketball at five original outdoor courts (a desert park in Phoenix, a fenced cage in New York, a beach court in Los Angeles, a neighborhood blacktop in Chicago, a rooftop in Kansas City), each with its own regulars: generated players with nicknames, reputations and street clothes. Play 1-on-1 up to 5-on-5 on a half or full court, to 11, 15 or 21, in 1s and 2s or 2s and 3s, win by 2 or not, make-it-take-it or losers' ball. Half court you check the ball up top and take it back past the arc after every change of possession; everywhere you call your own fouls (no free throws, no referees, no clock). Also: next game up (winners stay on, the rest of the line is simulated while you wait), 21 (everyone for themselves, free throws until you miss, go over and drop back to 13), HORSE (or PIG) and a 3-point contest with five racks and money balls. Play as any regular or any player from the three leagues. The parks are big Blender-built worlds that run to the horizon (desert ranges, a brick city block with an elevated train, a boardwalk with a pier and Ferris wheel, a Chicago neighborhood, a downtown skyline) with real 3D crowds that cheer and clap on big plays, plus the sounds of each place.
- Venues built in Blender: three small, classic and modern high school gyms (wooden or plastic bleachers, girders or open-web joists, a stage with curtains in the oldest gyms), a college fieldhouse with an arched brick-and-steel roof, a two-deck campus arena, and two pro arenas (suites ring, club level, halo video board). Each team's home is picked from its capacity and dressed in its colors: seats in team sections, painted walls and pads, LED ribbons, wordmarks, wall logos, live scoreboards, and championship and retired-number banners that match the program's history.
- Presentation: broadcast HUD, six cameras, commentary with optional voice, broadcast stat cards for hot scorers and free-throw shooters, a home crowd that cheers, groans, boos and chants (and jumps out of its seats on big plays), and fully synthesized sound with footsteps and squeaks matched to the animation.
- Instant replays and highlights: replay any moment with scrubbing, slow motion and five replay cameras; big plays replay automatically, and a highlight reel is ready at every break and after the game.
- Officials: a three-person crew works every game: the opening jump-ball toss, lead/trail/center floor positions that rotate on every change of possession, whistles with real signals (fouls, charges and blocks, traveling, three seconds, shot clock, goaltending, out of bounds, timeouts, substitutions, three-point attempts and makes), the visible five-second count, and handing the ball to inbounders and free-throw shooters. The scorer's table crew sits courtside.
- Game flow: quarter, halftime and timeout screens with line scores, team stats and leaders; team huddles; benches full of players who react to big plays; name tags; big-play banners (AND ONE, REJECTED, runs, buzzer beaters).
- Injuries (optional): falls, hard drives and awkward landings can hurt players, with forced substitutions and games-missed estimates.
- Never lose a game: games in progress save automatically every few seconds, and separate save slots keep different games side by side: three shared by Quick Play and the park, and three for Road to Legend. Resume or delete any of them from the main menu.
- Loading screens show real progress and gameplay tips that use your own key bindings.
- Phones and tablets: there are no touch controls, so games need a controller or keyboard. Menus, career management and simming work by touch.
- Works offline: after one visit the whole game is cached and playable without a connection, and it can be installed as an app.
- Settings for everyone: graphics presets with auto-detect, full key and button remapping, colorblind modes, subtitles, reduced motion, UI scale and tap-to-shoot.
Road to Legend is the career mode: start in high school, college or the pros, and every career chases the Legend title, decided at retirement for Icons only, with ranks from Local Hero up and Legend points for honors, winning, big moments and community impact. College is in, with coach trust and minutes, conference and national tournaments, NIL, the transfer portal, redshirts and the declare decision. The pros are in too: the combine and draft night, 82-game seasons, playoffs, All-Star weekend, contracts and free agency, trades, injuries, badges, endorsements, the Hall of Legends and retirement. Press conferences, a phone, a social feed, a mentor and a rival shape your personality and reputation along the way. In the off-season, pickup runs at the park build your street reputation. Create a player (name, Arizona hometown and school, position, archetype, body with rating caps, look with a live 3D preview, starting skills) and play four high school seasons. Each one has tryouts that place you on FR/SO, JV or varsity, mid-season call-ups, full schedules for all 283 schools, played or simulated games, a bench prompt, AIA-style state playoffs with an Open Division, natural development and skill points, season honors, grades and academic eligibility, summer camps, AAU showcases, star ratings with national and state rankings, and college recruiting (offers from D1, D2 and D3 programs, official visits, commitment, signing day, NIL estimates, reclassification and a college pick at graduation). Several careers save in the browser with autosave and export/import as .blcareer files. Franchise mode, roster editing, accounts and online play are in development.
Want to try what's coming next? The beta at https://legends.carterscoding.com/beta/ runs the version in testing. It shares saves with the main game, so a bug there can affect them.
Release notes for every version are in CHANGELOG.md, also shown in the game at /changelog (the version number in the main menu footer links there).
Leagues and teams
| League | In the game as | Teams |
|---|
| Pro | Pro Basketball League | 30 cities |
| College | National Collegiate Hoops | 1,092 programs in D-I, D-II and D-III across 100 conferences |
| Arizona high school | Arizona Prep Hoops | 283 schools, 6A through 1A, using the 2026–28 region alignment |
Real city, school and university names are used only to identify places. Every nickname, logo, color scheme, conference name, arena and player is original and fictional, with one exception: Brophy College Preparatory appears as the Brophy Prep Broncos in its red and white colors. Basketball Legends is not affiliated with the NBA, the NCAA, the AIA, or any team or school.
Development
Requires Node 22+.
npm install
npm run dev # http://localhost:3000
npm test # engine, simulation and camera-collision tests
npm run test:e2e # browser smoke tests against the production build (run `npm run build` first; uses your installed Chrome)
# CI runs the page tests only; the full-game @gpu flows need a GPU and run locally
npm run build # static export to out/ (also regenerates sitemap.xml)
Useful scripts:
npm run data rebuilds league data in src/data/generated/ from the factual lists in scripts/raw/.npm run assets:arenas rebuilds every venue from src/game3d/arena/variants.json with Blender (scripts/blender/build_arenas.py) and compresses them into public/models/arenas/.npm run assets:parks rebuilds the park worlds and the 3D spectators with Blender (scripts/blender/build_parks.py, build_crowd.py) and compresses them into public/models/parks/.npm run assets:icons rasterizes the app icons, favicon.ico and the link preview from public/icon.svg. The badge itself (with its lettering converted to outlines) is generated by scripts/brand/gen_icon.py, which needs Python with fonttools.npm run assets:player rebuilds the rigged player model with Blender 4.2+ (blender on your PATH) and compresses it.npx tsx scripts/dev/headless-game.ts 10 pro simulates full games headlessly and prints league-wide stats, which is useful for tuning (college and hs work too).npx tsx scripts/dev/injury-rate.ts 30 pro measures how often in-game injuries happen.npx tsx scripts/dev/defense-compare.ts 6 pro compares the defensive schemes; npx tsx scripts/dev/shot-mix.ts 4 pro shows the shot type mix.npm run lint runs ESLint (also part of the deploy workflow).npm run format formats the code with Prettier; npm run format:check (part of the deploy workflow) fails on unformatted files./dev/venues (dev server only) previews every venue dressed for any team from the game's camera spots./dev/logo (dev server only) is the logo lab: the title styles and logo marks that were considered, with a main menu preview./dev/anim (dev server only) is an animation lab: every procedural clip with a timeline, contact sheets (?sheet=1) and a side view (&profile=1).
npm run build also stamps out/sw.js (the offline service worker) with a build version and the list of hashed assets and models to precache.
Project layout
src/app/ pages (static export for GitHub Pages)
src/engine/ players, ratings, generation, rules
src/game/ match simulation, ball physics, AI, input, commentary
src/game3d/ three.js / React Three Fiber scene, characters, arena
src/ui/ HUD, menus, shared components
src/data/ generated league data
scripts/ data builders, Blender build scripts, sitemap, icons
Deploying
The site has two builds on one GitHub Pages site:
Pushing to either branch runs .github/workflows/deploy.yml. It checks out both branches, typechecks, lints, tests and builds each one (the beta with BL_CHANNEL=beta), runs the browser smoke tests against both, and publishes them together. If the beta fails on a push to main, the live game still deploys, together with the last beta that passed. If the beta fails on a push to prerelease, nothing deploys. The custom domain comes from public/CNAME.
BL_CHANNEL=beta npm run build builds the beta locally. It sets Next.js's basePath to /beta, so file paths go through asset() in src/lib/site.ts. It also shows a warning card on the main menu (the beta shares the browser's saves with the live game), tells search engines not to index the beta, renames the web app manifest, and gives the beta its own service worker, scoped to /beta/, with its own bl-beta-* caches. The live service worker ignores /beta/, and robots.txt disallows it. To run the smoke tests against a beta build, copy out/ into .e2e-beta/beta/ and run E2E_BASE=/beta E2E_SERVE_DIR=.e2e-beta npm run test:e2e.
Releasing a version: bump version in package.json (MAJOR.MINOR.PATCH; the main menu footer reads it at build time), add a section at the top of CHANGELOG.md, and paste that section into the GitHub release notes.
Credits and license
Code: MIT. Character base mesh: MakeHuman, CC0. See CREDITS.md for everything else.
