Paint something and observe how your painting dissolves into colourful vortices!

Fluid Paint for Android is a fluid physics simulation app, which enables you to interact with colorful liquid stuff on your smartphone or tablet! Besides from the Fluid Paint app, an interactive fluid wallpaper is offered. By tapping on the touch screen colorful liquids can be injected. Another way of interacting with the fluid is painting walls, which act as solid obstacles. Have fun with real time fluid dynamics!

The smoke itself can be visualized in different ways: Fluid particles have colors assigned to them, which usually are displayed directly. Additionally the temperature, velocity, vorticity and pressure distribution of the fluid can be viewed. The colors of the fluids and the wall can be set, and the visualization of physical properties like temperature or pressure can also be configured.

Implementation-wise both rendering and the computational fluid dynamics simulation are done exclusively with OpenGL ES 2.0 via glsl. This way the application could be implemented entirely in Java despite of the computationally expensive operations carried out in real time. For the computational fluid itself a grid based flow solver is used, which approximates solutions of the Navier Stokes equations numerically.

I hope to have aroused your interest in computational fluid dynamics (cfd) with this app.