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copied!<p>Because the box is axis-aligned, all you need to do is to check for interval intersection in each coordinate.</p> <p>Here is an example in python, with some tests. Note that it is generic for N dimensions, and it is the same algorithm for box-box intersection:</p> <pre><code>def are_intervals_intersecting(a0, a1, b0, b1): ''' @param a0: float @param a1: float @param b0: float @param b1: float ''' if (a1 < a0): a1, a0 = a0, a1 if (b1 < b0): b1, b0 = b0, b1 # 6 conditions: # 1) # a0 ---------- a1 a0 < b0 and a1 < b0 # b0 ---------- b1 (no intersection) # 2) # a0 ---------- a1 # b0 ---------- b1 (intersection) # 3) # a0 ------------------------ a1 # b0 ---------- b1 (intersection) # 4) # a0 ---------- a1 # b0 ------------------------ b1 (intersection) # 5) # a0 ---------- a1 (intersection) # b0 ---------- b1 # 6) # a0 ---------- a1 b0 < a0 and b1 < a0 # b0 ---------- b1 (no intersection) if b0 < a0: # conditions 4, 5 and 6 return a0 < b1 # conditions 4 and 5 else: # conditions 1, 2 and 3 return b0 < a1 # conditions 2 and 3 def is_segment_intersecting_box(P0, P1, B0, B1): ''' @param P0: tuple(float) @param P1: tuple(float) @param B0: tuple(float) @param B1: tuple(float) ''' for i in xrange(len(P0)): if not are_intervals_intersecting(P0[i], P1[i], B0[i], B1[i]): return False return True if __name__ == '__main__': assert not is_segment_intersecting_box( (0.0, 0.0, 0.0), (1.0, 1.0, 1.0), (2.0, 2.0, 2.0), (3.0, 3.0, 3.0)) assert not is_segment_intersecting_box( (0.0, 0.0, 0.0), (4.0, 1.0, 1.0), (2.0, 2.0, 2.0), (3.0, 3.0, 3.0)) assert not is_segment_intersecting_box( (1.5, 1.5, 0.0), (4.0, 2.5, 1.0), (2.0, 2.0, 2.0), (3.0, 3.0, 3.0)) assert is_segment_intersecting_box( (1.5, 1.5, 0.0), (4.0, 2.5, 2.5), (2.0, 2.0, 2.0), (3.0, 3.0, 3.0)) assert is_segment_intersecting_box( (1.5, 1.5, 1.5), (2.5, 2.5, 2.5), (2.0, 2.0, 2.0), (3.0, 3.0, 3.0)) assert is_segment_intersecting_box( (2.5, 2.5, 2.5), (2.6, 2.6, 2.6), (2.0, 2.0, 2.0), (3.0, 3.0, 3.0)) assert is_segment_intersecting_box( (2.5, 2.5), (2.5, 3.5), (2.0, 2.0), (3.0, 3.0)) print 'ok' </code></pre>

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