Is continuously seeding a random number generator performance intensive?

[Jeroen Bollen]

On Wednesday, 15 January 2014 at 21:23:03 UTC, Frustrated wrote:
> Anyways, now that you have your RND2D you don't ever have to 
> pre-generate your noise. Obviously it is more computationally 
> expensive though.

Thing is, the image is finite so I figured it'd be best to 
pre-generate a set of seeds, and then when I need a certain chunk 
of pixels simply quickly generate that one, like already 
suggested in this topic.