How to get a displacement limited to the visible area only (for stills)?

[Micha]

Hi,

for example I try to render a boat on the ocean and setup a large ground plane with displacement, than V-Ray needs a long time to create the displacement. If I check the scene in real time rendering than I see that the whole surface is displaced. I ask me, could it not be possible for rendering a still image to limit the displacement to visible space of the camera? So, geometry creation time and memory could be saved. Best would be if the displacement outside the camera range would be normal displacement.

-Micha