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view Resources/Computations/IntersectSegmentAndHorizontalLine.py @ 947:1091b2adeb5a toa2019081001

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Fixed animation frame stopping when returning false + big work on the OpenGL objects to make them lost context-safe + debug code to forcefully tag a context as lost + debug macros
author Benjamin Golinvaux <bgo@osimis.io>
date Sat, 10 Aug 2019 13:07:31 +0200
parents 35c2b85836ce
children
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#!/usr/bin/env python

from sympy import *

# Intersection between the 2D line segment (prevX,prevY)-(curX,curY) and the
# horizontal line "y = y0" using homogeneous coordinates

prevX, prevY, curX, curY, y0 = symbols('prevX prevY curX curY y0')

p1 = Matrix([prevX, prevY, 1])
p2 = Matrix([curX, curY, 1])
l1 = p1.cross(p2)

h1 = Matrix([0, y0, 1])
h2 = Matrix([1, y0, 1])
l2 = h1.cross(h2)

a = l1.cross(l2)

#pprint(cse(a/a[2], symbols = symbols('a b')))
pprint(a / a[2])