How do you make it so when an Animation toches an Object something happens

Question

How do you make it so when an Animation you can control touches an Object it gets bigger and grows in size? Like Agar.io how when you eat the blobs you grow in size, How do I make the same concept as that?

Answer 1

I haven't actually looked if Agar.io uses either canvas or WebGL, but it uses one of them. You should look up "canvas games using JavaScript".
I have a bunch of web canvas animations you could look at. I even have a code for people who want to get started with canvas.

Answer 2

Thanks @Zeke Williams I’ll take a look