Until svg will support conic gradients natively, this is the best I could come up with for one. For each degree turn, there is a new object involved with a linear gradient fill attribute. Objects are grouped and clipped together, and use the same linear gradient -meaning, you can change the steps at once by editing the gradient itself. May come handy in designing metallic buttons 二次曲线 渐变 逼近 圆锥形梯度
A parabola on a Cartesian coordinate grid. Typeface is Tuffy (public domain, created by Thatcher Ulrich) from openfontlibrary.org 代数 cartesian coordinates conic section 比喻