[Bf-python] Bundled scripts that use python extensions?

[Jonathan Merritt]

Hi Everyone,

I am currently working on a script that might be a good candidate for a 
bundled script: camera calibration.  This is sometimes called "camera 
matching" in a VFX context.  The idea is that by matching up points in 
an image taken by a real camera to locations of virtual points in 3D 
space, the camera position and orientation and its internal parameters 
("Lens", in the case of Blender), can be determined.  The virtual camera 
can be placed at the same relative spot in the virtual scene as the real 
camera occupied when the image was taken.  This is extremely useful for 
accurate Blendering on photos, image-based-modeling, etc.

The particular algorithm I'm using for camera calibration was developed 
by a guy called Roger Tsai and is quite complicated.  It first involves 
using a linear process to approximate the set of camera parameters, 
followed by a non-linear optimization by minimizing the sum of squared 
errors of the calibration points in image space.  Put simply, it would 
be *hell* to code in raw Python, and not exactly straightforward even 
with the current Python numerical libraries that are available.

Fortunately, a C implementation is already available here:
    http://www-2.cs.cmu.edu/afs/cs.cmu.edu/user/rgw/www/TsaiCode.html
I have substantially modified the code from that website to create a 
Python extension module (which wasn't so straightforward... try doing a 
"grep -R exit *" and feel my pain... :-)  I am currently tidying up this 
module prior to release, and adding in some decent test functions.

I'm just wondering what the policy will be for bundled scripts that 
require Python extension modules?  How will this work in a general case?

Thanks,

Jonathan Merritt.

PS - Is there a bundled scripts discussion group yet?  I did go looking 
(I promise) in the Wiki, but couldn't find one listed there.