Objfluid

Objfluid is a software framework and data format designed for simulating and storing fluid phenomena within polygonal scenes that rely on the Wavefront OBJ file format. It combines geometric models with particle-based fluid representations, allowing liquids to interact with surfaces defined by OBJ meshes. The goal is to enable cohesive integration of fluids into standard OBJ-based workflows used in computer graphics, visualization, and visual effects.

In objfluid, the fluid state is represented by a set of particles carrying attributes such as position, velocity, and optionally density or pressure. The format extends the OBJ ecosystem by providing accompanying data blocks or companion files that carry simulation state, enabling the preservation and exchange of both geometry and fluid information without departing from familiar OBJ tooling. This approach helps teams reuse existing modeling pipelines while adding dynamic liquid behavior.

Simulation methods commonly supported by objfluid include smoothed particle hydrodynamics (SPH) and, in some implementations, grid- or hybrid-based solvers. Boundary handling relies on mesh collisions against OBJ surfaces, sometimes augmented by simple friction models or signed distance field representations to prevent interpenetration and to capture boundary layer effects. Time integration may use explicit or semi-implicit schemes, with provisions for substepping to improve stability in complex scenes.

Typical workflows involve creating OBJ geometry, initializing fluid particle sets, running the simulation with objfluid, and baking results into cache files for rendering. Rendering may leverage volume shading, point-based representations, or particle systems within standard renderers, allowing artists to integrate fluid effects into scenes governed by OBJ-based assets.

See also: fluid dynamics, smoothed particle hydrodynamics, wavefront OBJ, particle systems.