GFA hanging forever

[marcocecchiscmgroup]

Dear Jens, I stepped into a solid example of the limits of the OpenCascade GFA. If you take the enclosed Fusion 360 example that I created to try out all the basic operations with solids, the solid conversion to STEP, the helix, hangs forever in surface.generalFuse(edges, tolerance):

	def build(self):
		if (self.__ready_to_build__):
			self.__ready_to_build__ = False
			edges = self.buildCoEdges()
			if (self._surface):
				surface = self.getSurface().build()
				if (surface):
					if (self.sense == 'reversed'):
						surface.reverse()
					if (len(edges) > 0):
						tolerance = 0.1
						component, elements = surface.generalFuse(edges, tolerance)
						faces = elements[0]

So, as it seems, the attempt to reduce the dependencies from Part for Issue #65, is stil causing troubles.

Even with the following hack, the processing takes a very long time, even if it doesn't hang.

Acis2Step.py:

def _convertFace(acisFace, parentColor, context):
	color = getColor(acisFace)
	if (color is None): color = parentColor
	try:
		#surface, sense = _createSurfaceFaceShape(acisFace)
		surface = None
		sense = acisFace.sense == 'forward'
		if (surface):
			face = ADVANCED_FACE('', surface, sense)
[...]

helix_cut.zip