<html><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">I am trying to craw (in 3D) an annulus colored in. Here is my code:<div>***************************************************************************************</div><div><div><span class="Apple-tab-span" style="white-space:pre"> </span>\begin{pspicture}(-2,-2)(2,2.5)</div><div><span class="Apple-tab-span" style="white-space:pre"> </span>\pscustom[fillstyle=solid, fillcolor=lightgray]{</div><div><span class="Apple-tab-span" style="white-space:pre"> </span>\parametricplotThreeD[liftpen=1](0,360){%</div><div><span class="Apple-tab-span" style="white-space:pre"> </span>t sin 2.24 mul t cos 2.24 mul 0%</div><div><span class="Apple-tab-span" style="white-space:pre"> </span>}</div><div><span class="Apple-tab-span" style="white-space:pre"> </span>\parametricplotThreeD[linecolor=gray,liftpen=1](360,0){%</div><div><span class="Apple-tab-span" style="white-space:pre"> </span>t sin t cos 0%</div><div><span class="Apple-tab-span" style="white-space:pre"> </span>}<span class="Apple-tab-span" style="white-space:pre"> </span></div><div><span class="Apple-tab-span" style="white-space:pre"> </span>}</div><div><span class="Apple-style-span" style="white-space: pre; "> </span></div><div>\end{pspicture}</div><div>*******************************************************************************************</div><div>which yields the picture in the attached pdf:</div><div></div></div></body></html>