Distance Line Line wrong result

[ArpegorPSGH]

When applying this node to parrallel lines, intersection flag is True instead of False (the distance between lines is far greater than Tolerance). Could this be corrected?

[zeffii]

it's behaving as intended, according to the code that implements that function.

 In case of parallel lines it will return the origin of the first line as the closest point 

sverchok/utils/geom.py

Lines 2479 to 2510 in 675f70c

	def distance_line_line(line_a, line_b, result, gates, tolerance):
	'''
	Pass the data to the mathutils function
	Deals with lines as endless objects defined by a AB segment
	A and B will be the first and last vertices of the input list
	In case of parallel lines it will return the origin of the first line as the closest point
	'''
	line_origin_a = Vector(line_a[0])
	line_end_a = Vector(line_a[-1])
	line_origin_b = Vector(line_b[0])
	line_end_b = Vector(line_b[-1])
	inter_p = intersect_line_line(line_origin_a, line_end_a, line_origin_b, line_end_b)
	if inter_p:
	dist = (inter_p[0] - inter_p[1]).length
	intersect = dist < tolerance
	is_a_in_segment = point_in_segment(inter_p[0], line_origin_a, line_end_a, tolerance)
	is_b_in_segment = point_in_segment(inter_p[1], line_origin_b, line_end_b, tolerance)
	local_result = [dist, intersect, list(inter_p[1]), list(inter_p[0]), is_a_in_segment, is_b_in_segment]
	else:
	inter_p = intersect_point_line(line_origin_a, line_origin_b, line_end_b)
	dist = (inter_p[0] - line_origin_b).length
	intersect = dist < tolerance
	closest_in_segment = 0 <= inter_p[1] <= 1
	local_result = [dist, intersect, line_a[0], list(inter_p[0]), True, closest_in_segment]
	for i, res in enumerate(result):
	if gates[i]:
	res.append([local_result[i]])

[zeffii]

i think your suggestion is valid.

[zeffii]

when the else is run, the dist = (inter_p[0] - line_origin_b).length part is (i think) likely (but depending on the orientation of the lines) to be an operation on the same vector3d. there inter_p[0] and line_origin_b are identical, and subtracting one from the other will result in a (0, 0, 0) and have 0 length

[ArpegorPSGH]

One solution is to calculate the angle between the line's directions and if it is 0 or 180, output false for intersection.

[ArpegorPSGH]

Well, after analysing it a bit, the problem just stems from a little mistake from the author of the function : instead of dist = (inter_p[0] - line_origin_b).length, it should be dist = (inter_p[0] - line_origin_a).length. Perhaps you could correct that, @zeffii.