I've seen literally dozens of "line segment" intersect solutions from my trip around the Internet, but that's not ideal for my situation.
Given a single point on each line and a vector representing the direction of said line, is it possible to tell whether the lines intersect?
I'm going to be implementing an algorithm to do this in C++ if it's possible without defining endpoints which (due to integral / floating point precision) will undoubtedly cause accuracy errors when dealing with lines that push the bounds of precision.
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$\begingroup$Two non-parallel lines $p_1+\mathbb R v_1$ and $p_2+\mathbb R v_2$ intersect if and only if $(v_1\times v_2)\cdot(p_1-p_2)=0$.
(But if you're implementing this in floating-point arithmetic, you're going to need to build in some safety margins anyway.)
$\endgroup$ 3 $\begingroup$You have 2 lines in the parametric notation $(a_1 +tv_1,a_2 + tv_2, a_3 + tv_3)$ and $(b_1 +sw_1,b_2 + sw_2, b_3 + sw_3)$, just compare component by component and see if you can find $s$ and $t$ sotisfying all the 3 equations. Otherwise transoform them in 2 cartesian equations and substitute.
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