Applying an SVG Radial Gradient Mask to Multiple Items

问题

I have a number of differently colored and sized svg circles that I would like to apply a radial gradient mask to. Is there a way to define a single mask that is applied to each circle by stretching it to match that circle's size?

Here is what I've come up with so far:

<radialGradient id="radialGradient" cx=".5" cy=".5" r=".5">
  <stop offset="0%" stop-color="white" stop-opacity="0"/>
  <stop offset="100%" stop-color="white" stop-opacity="1"/>
</radialGradient>
<mask id="radialMask" maskUnits="objectBoundingBox" x="0" y="0" width="1.0" height="1.0">
  <circle cx="0" cy="0" r="50%" fill="url(#radialGradient)"/>
</mask>

...

<circle cx="10" cy="10" r="10" fill="red" mask="url(#radialMask)"/>
<circle cx="100" cy="100" r="50" fill="blue" mask="url(#radialMask)"/>

The issue is that the percentage radius in the mask/circle doesn't seem to be measured relative to the size of the circle the mask is being applied to.

Is there a way of doing this without needing to define a new mask for each item I apply it to?

回答1:

You should set maskContentUnits="objectBoundingBox" too. That will make the mask contents relative to the size of the masked object.

来源：https://stackoverflow.com/questions/19414159/applying-an-svg-radial-gradient-mask-to-multiple-items