Random Gaussian cubic surface Seed: 187 (Gaussian coefficient and line-tracking seed)
Cubic: f(x,y,z) = 0.0113 x*z^2 +0.52 y*z^2 +0.0277 z^2 -0.161 x^2*z -0.212 x*y*z +0.056 x*z +0.151 y^2*z -0.0918 y*z +0.175 z -0.0496 x^3 -0.22 x^2*y -0.476 x^2 +0.336 x*y^2 -0.205 x*y +0.0147 x +0.0603 y^3 +0.255 y^2 +0.0146 y +0.304 1
Affine cubic: f(x,y,z) = 0.0113 x*z^2 +0.52 y*z^2 +0.0277 z^2 -0.161 x^2*z -0.212 x*y*z +0.056 x*z +0.151 y^2*z -0.0918 y*z +0.175 z -0.0496 x^3 -0.22 x^2*y -0.476 x^2 +0.336 x*y^2 -0.205 x*y +0.0147 x +0.0603 y^3 +0.255 y^2 +0.0146 y +0.304 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].