A sandbox that lets you interact with some of the fundamental forces of the universe.

Feedback welcome! I have no idea how to turn this into a complete game, or how this would become part of a larger game.

Technical details:

• 2d
• Incompressible
• 96x96 square mesh
• Staggered grid
• Fixed time step integration
• Hybrid density advection
  • Switches between conservative flux method and semi-Lagrangian based on cell Courant number
• Pressure projection solved via Gauss-Seidel iteration
• Gravitational potential solved via Gauss-Seidel iteration
  • Fixed BC with φ = 0
  • Note: ∇²φ = –4πGρ
• Velocity dampening of low density cells for stability
• Default open boundaries with toggleable no-slip
• Bilinear interpolation post processing
• Written in C++ using SDL2