Re: [boost] [GIL] locator and cached_location_t

Subject: Re: [boost] [GIL] locator and cached_location_t
From: fabien (fabien.castan_at_[hidden])
Date: 2010-12-17 19:14:26

> Cached location is meant to be used as a quick way to get to neighborhood pixels if you need to read or write a neighboring location frequently relative to a given locator.
> But the only reason you would prefer an iterator instead is if you want to move it. I cannot think of a case where you want to construct millions of iterators at fixed locations relative to a current locator... Can you explain why you would need such functionality?
I write a flood fill algorithm, so I often need to visit the 8 neighbors 
and next visit the new neighbors...
So I like the idea of moving my locator with 8 cached_location. For this 
kind of algorithm, we often need to move with the same steps, so I think 
it's interesting to use cached_location.
I don't think it's a so particular case.

PS: If you want to see my actual use as a concrete example.
https://github.com/tuttleofx/TuttleOFX/blob/master/plugins/image/process/filter/FloodFill/src/FloodFillAlgorithm.hpp