Ceq

Gather Question

Discussion created by Ceq on Apr 29, 2008
Latest reply on Apr 30, 2008 by michael.chu
I couldn't find anything about this in documentation:

When accessing gather streams inside a kernel, if you read out of stream bounds the currently behaviour is to read the nearest boundary element, for example, for gstream[8][8]:
gstream[(-1, -1)] is the same as gstream[(0, 0)]
gstream[(1, 10)] is the same as gstream[(1, 7)]

I've tested using CPU backend only, is the same for GPU?
Is this the standard behavior? Should we avoid it?
Can you rely it won't change in future versions?


Also, if you access gstream[(0.75, 0.75)] it is rounded to gstream[(1, 1)]
However, accessing gstream[(0.74, 0.74)] is rounded to gstream[(0, 0)]
This kind of rounding has surprised me a bit... how is it performed?


And last question: I've seen a few articles about Radeon 4870 launching next month and specs look quite promising, would it be supported too?

Thanks

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