adding ocean spectra

[meeotch]

I'm interested in "layering" large, low-frequency waves with higher-frequency ones.  The surface is no problem - just pipe the output of one ocean evaluate into the other.  But the ocean evaluate has other products (vel volume, sdf, particles) that are used elsewhere in the pipeline - and in fact some of those parts have their own embedded ocean eval nodes for generating those products.

 

I could hunt down and deform all the volumes, particles, etc.  But it occurred to me that a better solution would be to composite the two ocean spectra at the head of the chain.  Unfortunately, my math is too rusty for it to be immediately obvious to me how to do this.  (Adding them isn't the answer.)

 

Does anyone know how I could go about this?  I'm assuming the amp/freq/phase volumes that are output by the ocean spectrum node are spectra giving... power? in each band of frequencies across a given range.  But it's not really documented anywhere.

[fathom]

the ocean tools are implementing jerry tessendorf's ocean wave paper using volumes as the container for the data.  the voumes coming out of the ocean spectrum sop are, as i understand it, the phase, frequency, and amplitude of all the waves to be combined into your final displacement.  so if you have a 128x128 grid, you're combining 16,384 sin waves to get your displacement mapping.  at least, that's my grasp of how the fft stuff works.

 

you could TRY random samples from each volume, perhaps.  that might get you something.  not really sure.