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/* -*-ePiX-*- */
#include "epix.h"
using namespace ePiX;
int main()
{
bounding_box(P(-2,-2),P(2,2));
unitlength("1in");
picture(3,3);
offset(1.25, 0);
begin();
crop();
P V = P(2,-0.25), W = P(3,1);
P P1=P(-1.5,-1), P2 = P1 + V, P3 = P1 + 1.5*V; // points
P Q1 = P(-1,1), Q2 = Q1 + 0.5*W, Q3 = Q1 + W;
segment L12(P1, Q2), L13(P1, Q3);
segment L21(P2, Q1), L23(P2, Q3);
segment L31(P3, Q1), L32(P3, Q2);
P R1 = L12*L21, R2 = L13*L31, R3 = L32*L23; // points of intersection
dot(P1, P(0,-2), "$P_1$", b); dot(Q1, P(0,2), "$Q_1$", t);
dot(P2, P(0,-2), "$P_2$", b); dot(Q2, P(0,2), "$Q_2$", t);
dot(P3, P(0,-2), "$P_3$", b); dot(Q3, P(0,2), "$Q_3$", t);
red(); L12.draw(); L21.draw(); L13.draw(); L31.draw(); L32.draw(); L23.draw();
green(); Line(P1,P3); Line(Q1,Q3);
blue();
box(R1, P(4,2), "$p_1$", r);
box(R2, P(4,2), "$p_2$", r);
box(R3, P(4,2), "$p_3$", r);
dashed(); Line(R1,R3);
end();
}
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