23/07/16 22:06:31.48 xzU/43/d0.net
BC c1-b1 c2-b2
BP p1-b1 p2-b2
BA a1-b1 a2-b2
BC%o%BP (c1-b1)*(p2-b2) - (c2-b2)*(p2-b2)
BP%o%BA (p1-b1)*(a2-b2) - (p2-b2)*(a1-b1)
inner3 = \(p1,p2,a1,a2,b1,b2,c1,c2){
((c1-b1)*(p2-b2) - (c2-b2)*(p2-b2)) * ((p1-b1)*(a2-b2) - (p2-b2)*(a1-b1)) > 0
&
((a1-c1)*(p2-c2) - (a2-c2)*(p2-c2)) * ((p1-c1)*(b2-c2) - (p2-c2)*(b1-c1)) > 0
}