Re: [Plib-users] Problem with rotations

[Steve B. <sjb...@ai...>]

Ben Woodhead wrote:
> I did read these articles but I will read them again. But I did use a matrix
> stack from the rotations and I am only rotating around 1 axe. If I change
> the code to just rotate around x it works, and if I change it to rotate
> around just z there is no problem, but just y causes some really weird
> results. Did you have a look at the code..

Sorry - no - I've been kinda busy.  I've seen *thousands* of cases of
objects rotating nicely around the Y axis - so I'm not inclined to suspect
a bug in PLIB...but anything's possible.

Just to be *sure*, I went into examples/src/ssg/tux/tux_example.cxx - and
changed the line:

   sgSetCoord ( & tuxpos, 0.0f,  0.0f, 0.0f, frameno, 0.0f, 0.0f ) ;

...and switched 'frameno' from Heading (Rotation about Z) to Roll (Rotation about Y):

   sgSetCoord ( & tuxpos, 0.0f,  0.0f, 0.0f, 0.0f, 0.0f, frameno ) ;

...and tux leans to the right, gradually disappears under the pedestal and
reappears on the left...exactly as I'd expect.

----------------------------- Steve Baker -------------------------------
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