Mercurial > hg > orthanc-stone
annotate Resources/Computations/IntersectSegmentAndHorizontalLine.py @ 781:2bb72826fa3f
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author | Sebastien Jodogne <s.jodogne@gmail.com> |
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date | Mon, 27 May 2019 11:45:18 +0200 |
parents | 35c2b85836ce |
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rev | line source |
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35c2b85836ce
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Sebastien Jodogne <s.jodogne@gmail.com>
parents:
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1 #!/usr/bin/env python |
35c2b85836ce
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parents:
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2 |
35c2b85836ce
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Sebastien Jodogne <s.jodogne@gmail.com>
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3 from sympy import * |
35c2b85836ce
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Sebastien Jodogne <s.jodogne@gmail.com>
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4 |
35c2b85836ce
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Sebastien Jodogne <s.jodogne@gmail.com>
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5 # Intersection between the 2D line segment (prevX,prevY)-(curX,curY) and the |
35c2b85836ce
fix rtstruct projections
Sebastien Jodogne <s.jodogne@gmail.com>
parents:
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6 # horizontal line "y = y0" using homogeneous coordinates |
35c2b85836ce
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Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
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7 |
35c2b85836ce
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Sebastien Jodogne <s.jodogne@gmail.com>
parents:
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8 prevX, prevY, curX, curY, y0 = symbols('prevX prevY curX curY y0') |
35c2b85836ce
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Sebastien Jodogne <s.jodogne@gmail.com>
parents:
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changeset
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9 |
35c2b85836ce
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Sebastien Jodogne <s.jodogne@gmail.com>
parents:
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10 p1 = Matrix([prevX, prevY, 1]) |
35c2b85836ce
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Sebastien Jodogne <s.jodogne@gmail.com>
parents:
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11 p2 = Matrix([curX, curY, 1]) |
35c2b85836ce
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Sebastien Jodogne <s.jodogne@gmail.com>
parents:
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12 l1 = p1.cross(p2) |
35c2b85836ce
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Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
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13 |
35c2b85836ce
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Sebastien Jodogne <s.jodogne@gmail.com>
parents:
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14 h1 = Matrix([0, y0, 1]) |
35c2b85836ce
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Sebastien Jodogne <s.jodogne@gmail.com>
parents:
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15 h2 = Matrix([1, y0, 1]) |
35c2b85836ce
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Sebastien Jodogne <s.jodogne@gmail.com>
parents:
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16 l2 = h1.cross(h2) |
35c2b85836ce
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Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
changeset
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17 |
35c2b85836ce
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Sebastien Jodogne <s.jodogne@gmail.com>
parents:
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18 a = l1.cross(l2) |
35c2b85836ce
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Sebastien Jodogne <s.jodogne@gmail.com>
parents:
diff
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19 |
35c2b85836ce
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Sebastien Jodogne <s.jodogne@gmail.com>
parents:
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20 #pprint(cse(a/a[2], symbols = symbols('a b'))) |
35c2b85836ce
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Sebastien Jodogne <s.jodogne@gmail.com>
parents:
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21 pprint(a / a[2]) |