Add a sprite outline shader

[alice-i-cecile]

What problem does this solve or what need does it fill?

Shading the outlines of objects is a very common effect, either globally or when objects are selected.

This is much nicer to be able to do dynamically / procedurally than as part of your asset creation, because then the effect can be varied and different levels of outlining can be tweaked without having to redo assets.

What solution would you like?

We ship something configurable in the engine itself.

What alternative(s) have you considered?

We create a detailed high quality example teaching users how to do this.

[IceSentry]

If anyone's interested in implementing this, bevy would really need a generalized outline shader for any Mesh. It doesn't have to be 2d only. Making an outline using JFA should work the same way in 2d and 3d. With that said, sprites would need some special handling to generate the stencil texture. Here's an article that covers the JFA algorithm: https://bgolus.medium.com/the-quest-for-very-wide-outlines-ba82ed442cd9