PhysicsEngine

A 3D wireframe rendering engine built from scratch in Kotlin using Java Swing.

Note: This was one of my first projects, created in March 2021 when I was 13. The code remains unchanged from the original - this README was added later for archival purposes.

What it does

• Renders 3D cubes as wireframes
• First-person camera with WASD + mouse look
• Custom matrix math library for 3D transformations
• Perspective projection (world space → screen space)

Controls

Key	Action
W/S	Move forward/backward
A/D	Strafe left/right
Space	Move up
Shift	Move down
Mouse	Look around
ESC	Release mouse

How it works

The engine implements the 3D graphics pipeline manually:

1. Matrix.kt - Generic matrix class with multiplication
2. Math3d.kt - 4x4 transformation matrices (translation, rotation X/Y/Z, perspective projection)
3. Cube.kt - 8 vertices defined in 3D, projected to 2D for rendering
4. Camera.kt - Position, rotation, and input handling
5. Window.kt - Java Swing rendering loop

No OpenGL, no game engine - just Graphics.drawLine() and math.

Running

Requires Kotlin and Java. Built with Gradle.

./gradlew run

Author

Oliver Seifert (@ImGajeed76) - March 2021