Can shadow blur slow down canvas animations and performance?

Written by Richard Heyes, on 22nd September 2015

Canvas performance can be severely inhibited by using shadow blur. You have the option of turning off shadows completely or reducing the blurring effect.

Employing the canvas shadow blurring effect can slow down the performance of canvas based animations and effects - such as the Bar chart Wave effect seen here. What you see below is an example of a chart both using and not using shadow blurring.

Does it happen on all computers?

Not really. As you might expect it's more evident on slower and/or older computers. What the majority of your audience is may be the deciding factor - if your audience is likely to use regular or older computers you may want to choose a more applicable effect (eg a CSS based effect). However if you know or suspect that your audience uses more up-to-date computers then you have the choice of whatever effect you wish!

A Bar chart using the Wave effect and shadow blur

[No canvas support]

A Bar chart using the wave effect and NO shadow blur
[No canvas support]