Three types of particle solver available. Euler can take into account drag, or in the future more complex sims, Analytic will do the analytic solution to the phyics sim cpu side. This works nicely, but takes some bandwidth on the GPU bus to upload each position at each frame. Analytic can take into account emitter movement properly. 'AnalyticShader' runs the analytic solution on the GPU. Much faster to compute and next to no data on the bus, but cannot take into account emitter movement.