How can I outline text in Unity?

Question

Since it generates more triangles and vertices, the official outline script isn't a good way to do text outlining in my project.

How can I outline my text, with better performance?

TextMesh Pro may be the solution, but it'll increase the usage of memory heavily and our game is aimed at mobile platforms, so we want to minimise use of memory.

Answer 1

There is a very simple way to create outlined text. It's qill be a bit slower theoretically, but I've never come across a situation where an app was running slow because of this.

Let's say we have white text, and we want to outline it in black:

1. Draw the text in black, slightly offset to the left (1 or 2 pixels should usually suffice).
2. Do the same thing, but offset to the right.
3. Repeat steps 1 and 2, but offset the black text up and down.
4. Draw the white text without an offset.

If you need a very thick outline, and the offset distance increases, you may also want to draw the black text offset diagonally (in 4 directions)

Answer 2

Not sure if it works on mobile, but maybe this helps https://www.gamedev.net/blogs/entry/2264832-highlight-in-unity/. There are links in there for some other techniques which might suit you better also.

The idea is to have a second camera render the text you want to highlight in solid color, then create a dilated duplicate. Finally, you'd use the non-dilated render as a cutout for the first, effectively creating a solid outline. This outline render would then be passed to your main camera to be used as an 'overlay' RenderTexture.