For Each node for vex

[Tyfx567]

I know we all want this but has anyone actually found a way to be able to do this over points/ primitives?

Bad example but work with me:

Say I have a sphere and I want to: for every face delete point "0". This will make a weird triangle shape. for every face

 

In vex I can say something like this:

int primnumarray[] = array(@primnum);

foreach( int primnum; primnumarray) {
int listpoints[] = primpoints(0, primnum);
printf(sprintf("%s", listpoints) );



if(listpoints[0] == 0) {removepoint(0, @ptnum); 
}

}

The problem if you look at the print, it doesn't set for each face point numbers: 0,1,2,3. Instead it looks at the sphere as a whole and determines the point numbers from that even though I am telling it to iterate over the faces. How can I tell houdini to "isolate" each face just like the foreach node?

 

btw, I know my last bit of the code is wrong I don't know what to do for the last bit. 

 

Thanks guys for any help!

[pezetko]

Are you running it once as Detail? Or for each Primitives?

 

Let's assume that your sphere has unique points. So each polygon has 4 unique points.

What you want to do could be accomplished with this simple code, run it in Primitive Wrangle (Attribute wrangle run over primitives):

int geo = geoself();
removepoint(geo, vertexpoint(geo,vertexindex(geo, @primnum, 0)));

Function vertexindex() will generate linearvertex number for first vertex (index 0) of each polygon (primitive). Function vertexpoint() then convert this linearvertex number to actual point index.

[anim]

or simply:

removepoint(0, primpoints(0, @primnum)[0]);

the same requirements (unique points, prim wrangle)

[anim]

or if you want it to work on geometry with shared points (fused)

then you can recreate each prim without first vertex and delete original prim

int pts[] = primpoints(0, @primnum);
int newprim = addprim(0, "poly");
for(int i=1;i<len(pts);i++) addvertex(0, newprim, pts[i]);
removeprim(0, @primnum, 1);

if however you want original prim attrib values back the fastest would be to copy them from original geo afterwards

Edited August 26, 2015 by anim

[Tyfx567]

Wow that was fast responses! Thanks so much guys! So unique points in this situation is like where it is isolating the points per primitive? prim 1 = 0,1,2 prim 2 = 0,1,2? Just trying to understand

Edited August 26, 2015 by Tyfx567