ok
I recreate a new shader for my ocean.
no more surface model, no more rayhit, no more gather loop.
Trace node to manage reflection and refraction now.
Strange behavior with the specular node. The node owrks nicely without bump but when to change the normal, it produce way to bright pixels. Mantra is sometime unable to give a value to theses pixels. I have to use a clamp node …
. Hmm … it's not completely true : I would like to get some time to try instancing to fill a arena for a documentary project.