Random Gaussian cubic surface Seed: 257 (Gaussian coefficient and line-tracking seed)
Cubic: f(x,y,z) = 0.1 x*z^2 -0.29 y*z^2 -0.101 z^2 +0.491 x^2*z +0.341 x*y*z +0.0858 x*z +0.182 y^2*z -0.275 y*z -0.168 z -0.144 x^3 -0.197 x^2*y -0.105 x^2 -0.0536 x*y^2 -0.431 x*y -0.197 x -0.0876 y^3 -0.0587 y^2 +0.251 y -0.147 1
Affine cubic: f(x,y,z) = 0.1 x*z^2 -0.29 y*z^2 -0.101 z^2 +0.491 x^2*z +0.341 x*y*z +0.0858 x*z +0.182 y^2*z -0.275 y*z -0.168 z -0.144 x^3 -0.197 x^2*y -0.105 x^2 -0.0536 x*y^2 -0.431 x*y -0.197 x -0.0876 y^3 -0.0587 y^2 +0.251 y -0.147 1
Shadow: the quartic B(x,y)^2 - 4 A(x,y) C(x,y) = 0 is drawn on the z=-4 xy-plane in the same 3D scene. The translucent ruled curtain rises upward from the shadow to the ramification curve where the lifted point has z >= -2 and lies above the displayed projection plane. The 3 real projected lines on the xy-plane are bitangents found from the projective lines on the cubic surface. Same-color transparent line projection cones are included but hidden by default; use the page toggle to show them.
Viewing box: axis ranges are [-4, 4].