# Making a flickering outline

So I haven't seen this posted anywhere. I'm trying to get a as-much-as-possible hand drawn effect. I've noticed that flickering outlines can help a lot to achieve that look. However, I've tried many combinations but couldn't get a good result at all. I've put an example here https://youtu.be/NLKiEiJUyw4

Any clue on how to achieve this on Eevee would be very welcome, Thank you very much!

Example of a outline flickering effect

that would be grease pencil - traced object with a noise modifier on it. image1

You can also try a displacement modifier with an animated texture on your object with freestyle turned on.

The other option is to edit the freestyle settings, turn on noise, and give a low period, high amplitude and animation the seed based on frame (type #frame into seed)

• Thanks a lot! The grease pencil will also give a real hand drawn feeling to it. Thank you so much! – Zagr Jun 25 '20 at 13:47

You could try something like this. It doesn't give EXACTLY what you're looking for, but i'm sure after playing with some settings you could get somewhere close. This is as SHADER ONLY approach.

This is the setup I made:

What's basically going on here is that through a combo of a Mapping node, a Voronai Texture and a White Noise Texture , I generated a series of randomly gray-scaled vertical lines. I left in the Separate XYZ node even though I didn't use it because there is an option to only use the X coordinate if you want a more linear, less "noisy" look, but I think it looks better without, hence why I omitted it.

The key factor here is the Value node. Instead of using a number value, you can click on the field and input #frame. This will cause it to use the current frame number as a value, meaning you can use it to constantly change the position, and "scroll" the lines.

On the bottom is a simple recipe for Cel Shading. I wanted to get a bit of a hand drawn for the shadows, I used it and multiplied it with the white noise texture, using it's inverse as a factor. This comes in handy, because it lets you mask different parts of the shadows if you switch the mix positions. See below:

"Normal" mix position gives this shader look:

Or, (and this might look better) you can reverse the positions on the Mix Shader like this:

And the shader result of this.

You can adjust the colorramp values to get a more true-to-image copy of the style you're trying to achieve, and you can also go one further by adding Freestyle to give black outlines. I'm sure by tweaking the randomness of the Voronai Texture_ as well as playing with the values on the Mapping Node, you can get something maybe close to what you like. Anything more would require hand drawing (grease pencil), I think.

I hope this helps some.

• This is absolutely amazing Christopher, thank you very much for such a detailed answer. It is in fact a solid setup that I could tweak to achieve the result I want. Thanks again! – Zagr Jun 25 '20 at 13:49