Re: [PyOpenGL-Users] Modelview and projection matrices

[Maciej K. <ma...@dg...>]

On Sat, Jan 05, 2002 at 07:46:28AM -0500, Jan Ekholm wrote:
> However, the Python versions return a [4][4] matrix, while the C versions
> return a [16] array. The code on the page above uses a [16] array for all
> indexing, so I'd like to translate the matrices I get from glGetFloatv to
> arrays.
> 
> The problem is now that I'm not sure how the returned matrix should be
> "flattened". Should I go by row or column, i.e. the first element in the
> array should be [0][0], but should the second be [0][1] or [1][0] and so
> on?

The OpenGL matrices are stored in column-major order.  That is, the elements
from the flat [16] array correspond to the 4x4 matrix like this:

[  0  4  8 12 ]
[  1  5  9 13 ]
[  2  6 10 14 ]
[  3  7 11 15 ]

(Reference: "man" page for glMultMatrix)

-- 
Maciej Kalisiak|mac@] 
dgp.toronto.edu|www.] "He who laughs last thinks slowest!"
dgp.toronto.edu/~mac]