From: Angus Dorbie (dorbie++at++sgi.com)
Date: 01/13/2000 12:39:41
You either need two DCS coordinates, one for position and one for
rotation, this will be a rendering overhead but keep things simple for
you. You then model the head object coordinates around the origin and
translate to the neck using the first DCS, below this translation in the
scene graph but above the head geometry you can apply the rotation DCS.
The alternative approach which is better but involves a little more
thought is to construct a single matrix which moves the head to the
origin, rotates it and moves it back to the neck in your code. This is
the classic approach to rotating an object about a point. You then
specify the matrix you've calculated as the transformation the DCS will
apply. You need to know what the rotation point is ofcourse and will
have to measure it in the tool or derive it from the head bounding
coordinates.
Cheers,Angus.
pylonet++at++yahoo.com wrote:
>
> Hi All,
> I would be very happy if you could help me solve this problem:
>
> I use a robot model from Multigen. I want to ratote the head around its
> neck, but the head rotate around some axis far away the neck, although
> I have set the local coordinate to neck.
>
> Please tell me how to set DCS or other corrdinate system to overcome the
> problem.
>
> Thank you!
>
> Pylonet
>
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