Kevin Fitch wrote:
In hind sight I realize that the camera orientation did not change
so I removed the pointAt ( I just initialize the orientation ), but
things were still shaky. So I put axis.iv at the viewing point, and
this was still jumping around (w/ and w/o pointAt). The center of the
axes would move around (I believe it should be in the exact same spot
of the viewpoint the whole time). At this point I am guessing my
problem lies elsewhere in the application so I will try to construct a
minimal test case that reproduces the problem for me.
Kevin
I finally tracked down the source of the 'shaky' camera. I was using
very large numbers that change by rather small amounts, b/c that is how
the data is organized natively. There is enough precision in a double
for this to work, but when converting down to floats as is required for
Inventor I lose needed precision. I have been able to fix most of the
problems by recentering the coordinate system around where most of the
action takes place.
It would be easier on me if Inventor used doubles internally so that
I could use the native coordinate system for my problem. Has anyone ever
tried to make Inventor use doubles internally? Is there a reason why it
can't/shouldn't use doubles (would the extra bandwidth over the AGP, or
similar, bus be a performance killer?). I noticed that TGS inventor has
classes like SbVec3d, but according to the web page it still uses
float's internally.
Kevin
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