Kolja Kaehler wrote:
> Does anyone here have some advice for me on these matters? Maybe I am
> just missing “the obvious way” to organize these things.
I haven't had any problems using NumPy's row-major arrays with PyOpenGL.
For instance if you have a row-major NumPy array of dtype [ ( "x",
np.float32 ), ( "y", np.float32 ) ], you can pass the array directly to
PyOpenGL by putting it in a vertex buffer object and then using
glVertexPointer( 2, gl.GL_FLOAT, 0, None ) to tell GL to expect 2 floats
for each vertex. The same principle works for 3D as well.
And if you'd like to store several pieces of NumPy array data together,
then you can just use a recarray, and then pass an individual "member"
array to PyOpenGL at any point you want.
Perhaps you can give an example of what you're trying to do where the
row-major/column-major distinction gets in the way?
There really isn't a good way to dynamically grow a vertex array with
NumPy. Some options are:
* Use numpy.resize(), which just returns a new, larger array copy.
* Use numpy.ndarray.resize(), which can only resize if there are no
other references to the array.
* Accumulate and grow with a data structure other than a NumPy array,
and then convert to a NumPy array when you're done growing. Some
candidates are a Python list (slow), or if you're willing to use Cython
or C, then accumulate in a C array with realloc() for growing.
I haven't really used NumPy matrices, so I'll let someone else comment
on that one.