Random Gaussian cubic surface Seed: 426 (Gaussian coefficient and line-tracking seed)
Cubic: f(x,y,z) = 0.0525 x*z^2 +0.131 y*z^2 +0.242 z^2 -0.128 x^2*z +0.0132 x*y*z +0.0384 x*z +0.111 y^2*z +0.179 y*z -0.103 z +0.314 x^3 -0.189 x^2*y -0.0299 x^2 +0.0939 x*y^2 -0.209 x*y +0.0692 x -0.651 y^3 +0.0853 y^2 -0.469 y -0.075 1
Affine cubic: f(x,y,z) = 0.0525 x*z^2 +0.131 y*z^2 +0.242 z^2 -0.128 x^2*z +0.0132 x*y*z +0.0384 x*z +0.111 y^2*z +0.179 y*z -0.103 z +0.314 x^3 -0.189 x^2*y -0.0299 x^2 +0.0939 x*y^2 -0.209 x*y +0.0692 x -0.651 y^3 +0.0853 y^2 -0.469 y -0.075 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].