Random Gaussian cubic surface Seed: 295 (Gaussian coefficient and line-tracking seed)
Cubic: f(x,y,z) = -0.059 x*z^2 +0.306 y*z^2 +0.279 z^2 +0.0998 x^2*z +0.258 x*y*z -0.168 x*z -0.227 y^2*z -0.158 y*z -0.181 z +0.162 x^3 +0.00425 x^2*y -0.417 x^2 -0.0918 x*y^2 +0.448 x*y +0.0699 x +0.045 y^3 -0.191 y^2 -0.023 y -0.398 1
Affine cubic: f(x,y,z) = -0.059 x*z^2 +0.306 y*z^2 +0.279 z^2 +0.0998 x^2*z +0.258 x*y*z -0.168 x*z -0.227 y^2*z -0.158 y*z -0.181 z +0.162 x^3 +0.00425 x^2*y -0.417 x^2 -0.0918 x*y^2 +0.448 x*y +0.0699 x +0.045 y^3 -0.191 y^2 -0.023 y -0.398 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].