  The ALICE detector at CERN uses properties of the magnetic field acting on
charged particles as part of the particle tracking and identification system --
via measuring the strength of bending of charged particles in a magnetic field
supplied by electromagnets. During the calibration of the detector the magnetic
field was measured by the scientific team. The measurement points were then
fitted using Chebyshev polynomials to create a field model. That model is used
extensively in particle trajectory reconstruction, but for maximum
compatibility it is handled by CPU-only software. We propose multiple
approaches to the implementation of the model in a shader language, which
allows it to run in a graphical GPU environment. This makes the model run more
efficiently, as well as enables it to be used for field visualisation, which
was not previously done for ALICE.
