A retro lunar lander game built in C++ with Allegro 4, based on the tutorials by Deivid Coptero and expanded with additional levels, mechanics, and polish.
The goal is simple: pilot a spacecraft through obstacles and land it on a small platform without crashing. The game has 10 levels with progressively harder layouts.
Everything is drawn with Allegro's primitive functions — lines, rectangles, circles, and triangles. No sprites, no external assets for the game itself.
- 10 handcrafted levels with different obstacle types
- Newtonian physics — constant gravity, directional thrusters, velocity cap
- Geometric collision detection built from scratch (triangles, rectangles, circles)
- Static and moving circles with gravitational fields that pull the ship
- Procedural explosion animation using rotating line segments
- Reactive engine audio — sound turns on and off with thruster input
- Fuel system — using multiple thrusters drains fuel faster
- Animated starfield background
- Victory and game over screens
- 60 FPS game loop using Allegro's hardware timer
- More polished hitbox with five rectangles instead of tree
- polished the colisions with the base.
- Binary under 100 KB
| Key | Action |
|---|---|
↑ |
Main thruster |
← |
Left thruster |
→ |
Right thruster |
A |
Confirm / Retry |
ESC |
Exit |
| Level | Obstacles |
|---|---|
| 1 | Open space, just gravity |
| 2–3 | Floor and ceiling triangles |
| 4–6 | More triangles, tighter gaps |
| 7 | Triangles + falling rocks |
| 8 | Large rectangular blocks |
| 9 | Static circles with gravity fields |
| 10 | Moving circles with orbits |
gravity = 0.05 per frame (downward)
thrust force = 0.09 per thruster
max speed = ±4.0 (both axes)
Landing is valid only when vertical speed vy < 1.0. Higher speed triggers an explosion.
- Triangles — point-in-triangle test using cross products, plus segment-segment intersection
- Circles — segment vs circle using the quadratic formula
- Gravity fields — directional force applied when the ship enters a circle's radius of influence, scaled by distance
A Nix flake is included for a reproducible development environment with Allegro 4.
# Enter dev environment
nix develop
# Compile
g++ moonlanding.cpp $(pkg-config --cflags --libs allegro) -lm -o moonlanding
# Run
./moonlandingA pre-compiled binary for Linux is also included.
moonlanding/
├── moonlanding.cpp # Full source (single file)
├── moonlanding # Pre-compiled Linux binary
├── flake.nix # Nix dev environment
├── splash_nix.bmp # Intro screen
├── victoria_art.bmp # Victory screen
├── pdpsong.wav # Intro music (PDP-1, 1962)
├── gamesong.wav # Background music
├── thrust.wav # Engine sound
├── boom.wav # Explosion sound
├── sonidostart.wav # Start sound
└── victory_fixed.wav # Victory music
The intro track is a piece performed by a PDP-1 at MIT in 1962, using the Harmony Compiler written by Peter Samson — one of the earliest programs to produce polyphonic music on a digital computer.
| Language | C++ |
| Library | Allegro 4 |
| Resolution | 740 × 500 px |
| Target FPS | 60 |
| Binary size | < 100 KB |
| Platform | Linux / NixOS |
| Rendering | Software, double-buffered |
