"active" infection based growing solver doesn't cook well

[sasbom]

Hey!

I was going through some tutorials on growth solvers, and I noticed that a lot of them are driven by the
"food" group looking to get "infected" if you know what I mean. I wanted to try and make a growth solver that workes differently, 
looking instead at the points that are already infected and infecting more from their perspective.

A very simple summation of what I'm trying to achieve:

1. List the points around me

2. If they are food, they are candidates

3. Infect only 1 of the found candidates

rinse and repeat

I've put the code underneath in a point wrangle in a solver, but it doesn't work well.
I tried running the command on the seperate food and infected groups but that doesn't seem to improve either.

What happens when it doesn't go well:

1. nothing

2. Almost every point gets put into the infected group in 1 framespan and then the solver doesn't do anything anymore.

//initialiation of radius to search for, and random seed;

float radius = 0.2;
float seed = 8008135;

//stalking prey (finding a list of points to infect);

int neighbours[] = nearpoints(0,@P,radius,5);

//hopefully grabbing a random one out of the stack of many;

float array_length= len(neighbours);
//random number between 0 and the length of the list of neighbours;
int targetp = rint( rand(seed) * array_length);
//looking up point ID in list of neighbours;
int point_to_infect = neighbours[targetp];

//actually infect the point, if it is food;

if (point(0,"infection",point_to_infect) == 0){
    setpointattrib(0,"infection",point_to_infect,1);
    };

I haven't any clue what's going on, I got no errors other than a little green line under the local variable "targetp" when it gets created.

I've attached my .hip! It might be something else I'm doing wrong.

I hope you can help me, thanks in advance,

Sasbom

active infection.hip

[Yon]

you were missing 
1) condition to only run on infected points
2) I cannot infect the point that infected me, which you can get around by changing the target seed by time
though there is prob a smarter way by removing infected points @ptnum from the candidate array

also to iterate correctly in a solver sop you want to fetch the results from last frame and run over that



active infection.hip

[sasbom]

Thank you so very much. This is a great help!

Have a nice day/night/whatever!