In Inkscape if you have two filled circles. A big solid red one and a smaller, blurred and pinky one, like this:
You can use the mask to trap one inside another to create a light effect.
Metaphorically, I drew a mask using the mask effect:
You can download it here: mask_inkscape_by_silveiraneto.svg
As always, you can use or modify it under the Creative Commons Attribution Share-Alike license.
Two vector drawing I did to a friend. It’s anime-chiby style character, the first mixed with a cat and the second with a bunny. I did using Inkscape. As always, both under the Creative Commons Attribution-Share Alike license.
Download: black_cat.svg
Download: white_bunny.svg