Originally those were assertions that were kept even in release builds,
which meant that calling math.angle() on non-normalized vectors aborted
the whole Python interpreted. Not great. But then the assertions were
made debug-only, which means invalid usage from Python (where the
bindings are usually only built as Release) now silently gives back a
wrong result, which is perhaps even worse.
Because the Python overhead is already massive due to all string lookup
and such, doing one more check in the implementations isn't really going
to slow down anything. Thus I'm mirroring all (debug-only) Magnum
assertions on the Python side, turning them into exceptions. With proper
messages as well, because those are extremely useful.
This is so ugly it's beautiful. The translation needed a metaclass to
work properly, but the undoubtedly worst/best is making those exposed
nicely in the docs.
This makes Vector3 to np.array conversion about 20x faster. Yes, *that*
much. Crazy. Timings from the benchmark added in previous commit before:
np.array([]) 0.66096 µs
np.array([1.0, 2.0, 3.0]) 0.70623 µs
a = array.array("f", [1.0, 2.0, 3.0]); np.array(a) 0.57877 µs
a = Vector3(1.0, 2.0, 3.0); np.array(a) 18.18542 µs
after:
np.array([]) 0.57162 µs
np.array([1.0, 2.0, 3.0]) 0.68309 µs
a = array.array("f", [1.0, 2.0, 3.0]); np.array(a) 0.53958 µs
a = Vector3(1.0, 2.0, 3.0); np.array(a) 0.74818 µs
There's still some overhead that could be removed I think, making the
Vector3-to-numpy conversion faster than list-to-numpy.
Vladimír Vondruš