Random Gaussian cubic surface Seed: 284 (Gaussian coefficient and line-tracking seed)
Cubic: f(x,y,z) = 0.0248 x*z^2 -0.0481 y*z^2 -0.123 z^2 +0.107 x^2*z +0.281 x*y*z +0.0425 x*z +0.052 y^2*z +0.133 y*z +0.319 z -0.145 x^3 +0.146 x^2*y +0.331 x^2 -0.435 x*y^2 +0.135 x*y +0.228 x +0.0577 y^3 +0.513 y^2 -0.287 y +0.0915 1
Affine cubic: f(x,y,z) = 0.0248 x*z^2 -0.0481 y*z^2 -0.123 z^2 +0.107 x^2*z +0.281 x*y*z +0.0425 x*z +0.052 y^2*z +0.133 y*z +0.319 z -0.145 x^3 +0.146 x^2*y +0.331 x^2 -0.435 x*y^2 +0.135 x*y +0.228 x +0.0577 y^3 +0.513 y^2 -0.287 y +0.0915 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 7 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].