On Feb 3, 6:00 pm, "Nicholas" <Yue.Nicho...@[EMAIL PROTECTED]
> wrote:
> Does anyone know of a good place to get a good understanding of the
> camera transformation between 3d application and renderman?
Any book about 3D computer graphics. :)
RenderMan is not special in the way it defines a camera. It uses a
left-handed coordinate system, that's it. Using rotations and
translations (an maybe scales as well) stacked atop is just another
way, perhaps more human readable, of specifying what can, in case of a
RenderMan camera, be fitted into single 4x4 matrix for the orientation
and one RiProjection() call. Unless people need to re-orient the
camera by hand-editing the RIB..
So why not just use a 4x4 matrix with RiTransform()?
It's quite straightforward to go from e.g. eye, target, up to 4x4. And
the right-handed issue you can address by concatenating a negative
scale on z into the 4x4 matrix, then doing a RiReverseOrientation()
immediately after your camera transform definition.
I believe to recall that this is also what MtoR does. The advance is
that coordinates in the RIB reflect those in your 3D app.
Cheers,
Moritz
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