Geometry Boost List: [ggl] Efficient rotation about a point

Subject: [ggl] Efficient rotation about a point
From: Stephen Leary (sleary)
Date: 2009-11-29 13:49:54

This is usually acomplished by producing a matrix that represents
-translate/rotate/+translate then applying that matrix transform once. I
havent checked to see if GGL supports matrix transforms but that is how i
would approach this use case in "real life". The matrix gets built once and
reused as many times as needed.

Stephen

On Sun, Nov 29, 2009 at 6:43 PM, Lee <lee_at_[hidden]> wrote:

> Hi,
>
> What is the best way (in terms of efficacy) to rotate a ring about a point
> in GGL?
> Looking at GGL it seems right now to require three separate passes over the
> point
> data: -translate/rotate/+translate. Can't this be done in some kind of
> single pass
> 'rotate_about_transformer'?
>
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-- 
Stephen Leary
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