- https://www.visualcinnamon.com/2016/06/fun-data-visualizations-svg-gooey-effect/
- http://bl.ocks.org/nbremer/0e98c72b043590769facc5e829ebf43f
- http://bl.ocks.org/nbremer/e627a8fced026a9286932c6c0a02d71b
- http://bl.ocks.org/nbremer/8df57868090f11e59175804e2062b2aa
- http://bl.ocks.org/nbremer/f6952f1ef900d84be918
- http://bl.ocks.org/nbremer/a3684c52fb527c8fa415
- http://bl.ocks.org/nbremer/69808ec7ec07542ed7df
- http://bl.ocks.org/nbremer/0e98c72b043590769facc5e829ebf43f
glow filter
https://www.visualcinnamon.com/2016/06/glow-filter-d3-visualization/
<svg width="30" height="30">
<g class="svgWrapper">
<defs>
<filter id="glow">
<feGaussianBlur class="blur" stdDeviation="4.5" result="coloredBlur"></feGaussianBlur>
<feMerge>
<feMergeNode in="coloredBlur"></feMergeNode>
<feMergeNode in="SourceGraphic"></feMergeNode>
</feMerge>
</filter>
</defs>
<circle class="exampleGlow" cx="10" cy="10" r="3" style="fill: rgb(204, 51, 63); filter: url('#glow');"></circle>
</g>
</svg>
here