Why is numpy not a build dependency

[rickstaa]

I noticed that when Numpy is not pre-installed before installing Pybullet, Pybullet is compiled without Numpy support:

bullet3/setup.py

Lines 91 to 101 in 39b8de7

	try:
	import numpy
	NP_DIRS = [numpy.get_include()]
	except:
	print("numpy is disabled. getCameraImage maybe slower.")
	else:
	print("numpy is enabled.")
	CXX_FLAGS += '-DPYBULLET_USE_NUMPY '
	for d in NP_DIRS:
	print("numpy_include_dirs = %s" % d)
	include_dirs += NP_DIRS

Since this leads to a non-standard and somewhat unexpected install procedure and forces developers to handle this difference upstream, I was curious why numpy is not a build dependency instead. Maybe to give people the ability to have the getCameraImage function to return a 2D tuple (i.e. [channel, width * height) instead of a 3D numpy array (i.e. [height, width, channel]) 🤔? I am likely overlooking something here, or there were problems six years ago when @erwincoumans added this code in fec96ab17f2c29003775d0e3cb117a71ee7b8bb3 that are no longer a concern, but I think having numpy as a build dependency would be more convenient.