an class='id identifier rubyid_new'>new</span><span class='lparen'>(</span><span class='id identifier rubyid_x'>x</span><span class='comma'>,</span> <span class='id identifier rubyid_y'>y</span><span class='comma'>,</span> <span class='id identifier rubyid_z'>z</span><span class='comma'>,</span> <span class='id identifier rubyid_r'>r</span><span class='rparen'>)</span>
</code></pre>

<p>If left unspecified, the radius (<em>r</em>) defaults to 1.0.</p>

<p>Another option is to initialize the sphere with a sp