A real-time Smoothed Particle Hydrodynamics (SPH) fluid simulation running entirely on the GPU. Built from mathematical first principles using CUDA and OpenGL interop — no game engines, no pre-built solvers.
Designed for curiosity, and learning GPU-accelerated physics. Scales comfortably from 10k to 200k+ particles at interactive frame rates real-time also capable of running large simulations upto 1 million particles for non real-time renders to use it turn on "simulated" option from ui .
2026-06-13.21-22-25.mp4
- Windows (only supported platform)
- NVIDIA GPU (CUDA-capable)
There is no CMake. The build is two steps:
Step 1 — Compile the compute engine
Open build_cuda.bat and verify the path to compute.cu is correct for your machine. Run the .bat file. This produces compute.lib, which contains all CUDA kernels.
Step 2 — Build the main project
Compile the rest of the project normally (MSVC). Link against compute.lib and the standard dependencies (CUDA runtime, GLFW, GLAD, ImGui).
If CUDA compilation fails, the most common fix is adjusting the sm_ architecture flag in build_cuda.bat to match your GPU.
| Input | Action |
|---|---|
| LMB drag | Rotate camera |
| Scroll wheel | Zoom in / out |
| W / A / S / D | Move camera |
| Q | Move camera up |
| E | Move camera down |
| Space | Pause / unpause |
| K | Restart simulation |
| H | Toggle UI visibility |
| X | Toggle debug overlay |
- proper ui with multiple tuneable parameters in multiple tabs
- 3 rendering styles(in rendering tab) 1=native particles with velocity rgb(also allows selecting color for particle) 2=screen space effect for a blured fluid (looks decent) 3= ray marching fluid with great visuals(fps may fluctuate)
- "simulated" option in ui allows switching from real-time to frame to frame.
- tuneable fluid boundaries from ui in world tab(box can be hiiden from ui).
- "wave generation" option in ui help to form waves for better visuals.
- floor size,color can be tuned live fron ui
- dymanic sky with moveable sun
- Debug overlay showing per-particle density, pressure, and neighbor counts -dynamically emit particles with reallocation live (using preallocated buffer for emitter).
- The simulation runs a standard force-based WCSPH pipeline each frame, fully on the GPU
- uses trait eos for pressure
- xsph for velocity smoothing
- viscosity for motion damping
- velocity verlet intigration
Press X to enable the debug overlay. Displays avg per-particle:
- Neighbor count
- Estimated density
Useful for diagnosing clumping, pressure spikes.
Open-source. Free to use, modify, and learn from.
Built from scratch in CUDA C++ and OpenGL — no game engine, no pre-built physics library.
