This VOP evaluates and samples ocean displacement, velocity, and/or cusp values from layered ocean spectra created via one or more Ocean Spectrum nodes.
The spectra are input to the Geometry File parameter. Optionally, any animated mask volumes from the spectra can be input to the separate Mask Geometry File parameter to split static spectrum geometry from animated mask geometry and save disk space. This VOP will internally execute an inverse Fast Fourier Transform to evaluate any spectral ocean input, so can be used for render-time evaluation of ocean spectra. The Sample Position input should generally be in object space.
In SOPs the Geometry File parameter can also be the evaluated "rest volume" output of an Ocean Evaluate SOP, such as Rest Displacement, in which case no internal FFT execution is required.
During rendering this VOP will automatically downsample any input spectra when the smallest wavelength present in the spectra becomes too small to resolve with the current shading sample area, which would otherwise lead to aliasing. The Anti-Alias Blur parameter is a scale on the shading sample before measuring against wavelength. Decrease its value to reduce the amount of downsampling done, or set to zero to disable completely. This parameter currently only has an effect in the Displacement and Surface contexts.
The remaining parameters match the equivalent ones on the Ocean Evaluate SOP.