I’m having trouble making a paint trail effect in ShaderGraph. What am I doing wrong? Are there other ways of doing this?

Link to what I have so far: https://i.imgur.com/UzFUtrT.gif

Link to ShaderGraph of the original render texture: https://i.imgur.com/orlufI0.png Link to ShaderGraph of the output render texture: https://i.imgur.com/nUfYFu2.png

I’m trying to make the quad on the right leave a trail of cyan when the circle moves. Both squares use different materials.

I’ve tried using Graphics.Blit to draw the current texture onto a new one but it doesn’t create any painting effect (code: https://hatebin.com/rlmjuzilmn).

The only progress I’ve gotten is from creating a RenderTexture and using SetPixel in a C# script but its very inefficient and slows down my computer too much: https://i.imgur.com/9617OYQ.gif

I’ve been going about this for weeks. What am I doing wrong? What are the other options I have?

I would like to avoid writing shader code if possible. I’m looking for relatively simple and easy to understand solutions.