eyeball curve

x(t) = cos(t) (a sin(t) + b sqrt(1 - p cos^2(t)) + c sqrt(1 - q cos^2(t))) y(t) = sin(t) (a sin(t) + b sqrt(1 - p cos^2(t)) + c sqrt(1 - q cos^2(t)))

r(θ) = a sin(θ) + b sqrt(1 - p cos^2(θ)) + c sqrt(1 - q cos^2(θ))

closed | parametric | polar | simple

A = 1/2 π (a^2 + 4 b c F_1(1/2 ;-1/2, -1/2;1;p, q) - b^2 (p - 2) - c^2 (q - 2))