2D Fluid Simulation

Version: 0.975 Raw

Author: SL1dee36

This program simulates a 2D fluid using the Smoothed Particle Hydrodynamics (SPH) method. It allows users to interact with the fluid by creating new particles and manipulating existing ones.

Currect verison demo: https://www.youtube.com/watch?v=xbR4eWPZM4s

Old verison demo: https://github.com/user-attachments/assets/170b9447-a075-4b4f-9c04-e5bc13744b59

Features

• Realistic fluid behavior: Simulates fluid movement, pressure, viscosity, and interaction with boundaries.
• Interactive controls:
  • Left Mouse Button: Creates new particles at the cursor position.
  • Right Mouse Button: Drags and interacts with particles within a radius.
  • 'S' Key: Resets the velocity of all particles.
• Obstacle interaction: Includes a circular obstacle that particles can collide with.
• Visual representation: Renders particles with a color gradient based on their speed.
• Performance optimizations: Implements efficient neighbor search and force calculation algorithms.

Dependencies

• SDL2: Simple DirectMedia Layer 2 library for graphics rendering and input handling.

Building and Running

1. Install SDL2: Instructions for installing SDL2 can be found on the official website: https://www.libsdl.org/download-2.0.php
2. Compile the code: Use a C++ compiler that supports SDL2 (e.g., g++):

   g++ -o fluid_simulation fluid_simulation.cpp -lSDL2

3. Run the executable:

   ./fluid_simulation

Configuration

The simulation parameters can be adjusted by modifying the constants at the beginning of the code:

• WIDTH and HEIGHT: Dimensions of the simulation window.
• FPS: Frames per second.
• PARTICLE_RADIUS: Radius of each particle.
• GRAVITY: Strength of the gravitational force.
• REST_DENSITY: Rest density of the fluid.
• GAS_CONSTANT: Gas constant used in pressure calculation.
• VISCOSITY: Viscosity of the fluid.
• PARTICLE_CREATION_RATE: Number of particles created per frame when the left mouse button is held down.
• COHESION_STRENGTH: Strength of the cohesion force between particles.
• DAMPING: Damping factor applied to particle velocities.
• DRAG_COEFFICIENT: Drag coefficient applied to grabbed particles.
• GRAB_RADIUS: Radius within which particles are affected by the right mouse button.
• SPRING_CONSTANT: Spring constant used in the spring force calculation.
• OBSTACLE_X and OBSTACLE_Y: Position of the circular obstacle.
• OBSTACLE_RADIUS: Radius of the circular obstacle.
• WALL_THICKNESS: Thickness of the walls (currently set to 0 for optimized rendering).
• WALL_COLOR: Color of the walls.
• PAD_X and PAD_Y: Padding between the walls and the simulation area.
• GRADIENT_STEPS: Number of steps in the color gradient.
• max_speed: Maximum speed for color mapping.

Known Issues

• Performance may degrade with a large number of particles.
• The simulation is not perfectly accurate and may exhibit some unrealistic behavior in certain scenarios.

Future Improvements

• Implement more advanced SPH features, such as surface tension and boundary handling.
• Optimize performance further to handle more particles.
• Add more interactive features and customization options.

License

This project is released under the MIT License. See the LICENSE file for details.