Niagara Falls Lab is a real-time waterfall simulation that captures the dramatic scale and atmospheric effects of cascading water. The shader combines multiple layered techniques to create a convincing waterfall: flowing water columns with turbulent noise, mist clouds rising from the impact zone, spray particles caught in updrafts, and prismatic rainbow refraction through the mist.
The water flow uses domain-warped FBM noise to create the appearance of churning, frothing water cascading over the cliff edge. Below the falls, impact dynamics generate billowing mist clouds modeled as volumetric density fields. Spray droplets are scattered upward from the turbulent base. When viewing angle and light direction align, a rainbow arc appears through the mist via wavelength-dependent refraction.
Parameters control water flow rate, mist density, spray intensity, wind direction, and sun angle for rainbow positioning.