Point Replication Procedural Help

[xcchox]

I was wondering if there's a way to replicate points along a spline/curve through cvex?

 

I know that you can replicate points along an line by storing the normal direction of the line and the distance and then multiplying by a random number to generate the replicated points but is there an way to do this same effect using a curved line?

 

[fathom]

you can create any sort of pattern you want.  the trick is figuring out how to define that pattern in terms of point attributes and then how to code the cvex to use them.

 

this is off the top of my head and it's late... so....

 

bezier curves are not very hard.  you'll need to set up some vectors on your points first, tho.  create tangent vectors on each point (these are the bezier "handles").  the tangent vector for P1 would be P2-P0 for a smooth curve, i think.  so once those are all defined on your geometry, you'll need to include the next point's P and tangents for the current point.  the end result will be each point will have 4 vectors: P, tangent, P_next, tangent_next.

 

your cvex code then just needs to pick a random u value (0-1).

P_next = P_next - tangent_next;

Pa = P + tangent * u;

Pb = lerp(P+tangent, P_next, u);

Pc = P_next + tangent_next * u;

 

Pd = lerp(Pa,Pb,u);

Pe = lerp(Pb,Pc,u);

 

P = lerp(Pd,Pe,u);

 

 

wow, hopefully i haven't completely mangled that.

 

 

also, you'll need to pick a good multplier based on the distance of your line segment.