[Unity Shader Graph] Net Diagram

SnowInChina

i would like to create a diagram shader in unity shader graph, but i cannot find anything on how its made

it should like something like the red line going from point to point

any pointers ?

i could propably do this with c# and the line renderer, but i would like to have it as a shader

Eric Chadwick

What decides the position of the red vertex along the edge?

SnowInChina

input value 0-1, the vertex itself doesnt have to get displayed, the graph would suffice

zero is the middle of the graph, so they have a radial arrangement

SnowInChina

okay, someone told me a neat trick

if i create a 7sided polygon and unwrap that in the 2nd uv channel into a rectangle, i can create 7 evenly spaced stripes which i can fade from black to white through the inputs and displace the vertices on their normal direction.

and then either create an outline shader or something along the line. genius

gonna try that

poopipe

The code in the Combining Powers section on this page shows you how to generate the distance field for an ngon
https://thebookofshaders.com/07/

At the end he smoothsteps the distance field to get a nice antialiased mask  - if you subtract from the distance (offsetting the zero point) and abs() the distance field you will get a line :
eg.
   d = abs(cos(floor(.5+a/r)*r-a)*length(st) - 0.5);
   color = vec3(1.0-smoothstep(.0,.01,d));

this next bit is speculative (as in I haven't tried it)
To get the wobble you would offset the distance by adding/subtracting from the distance field prior to calculating d  
The rectangular stripes/texture you have now but converted to polar coordinates  would probably be quite good for that 


should add that atan is a lot less good than atan2 so if you have the option, always use atan2

SnowInChina

thanks, but thats too deep into scripting for me

i can do some c# and have a beginner understanding of scripting, but thats a little bit too much (for now at least)

poopipe

It's basically doing what you did with the UVs anyway really so probably not a big difference 😁