I let AI write my scatter VEX — instances stop looking identical (quick demo)

[houdini vfx3d]

Quick one. Scattering rocks (or any asset) on terrain and every copy comes out facing the same way at the same size — that fake, stamped-out look. The fix is a proper orient setup so each instance gets its own rotation and scale without flipping.

The tricky part is the orient quaternion — do it from N alone and instances flip. The clean way is a full stable orient (Shoemake uniform rotation) plus a random uniform scale, exposed as sliders:

    // Point Wrangle between Scatter and Copy to Points, run over Points
    int   seed = chi("seed");
    float smin = ch("scale_min");
    float smax = ch("scale_max");

    vector u = rand(set(@ptnum, seed, 0));
    float r1 = sqrt(1.0 - u.x);
    float r2 = sqrt(u.x);
    float t1 = 2.0 * PI * u.y;
    float t2 = 2.0 * PI * u.z;

    p@orient = set(sin(t1)*r1, cos(t1)*r1, sin(t2)*r2, cos(t2)*r2);

    float s = rand(set(@ptnum, seed, 1));
    @pscale = fit01(s, smin, smax);

I made a short video walking through it end to end (build the scatter, hit the problem, generate the VEX, paste, done):
https://www.youtube.com/watch?v=0FxEAaKmLBU

The VEX in the video was generated by a Houdini skill I built for AI agents — it's on my Gumroad if useful, but the code above is the whole fix, free. Feedback welcome.

[tamagochy]

You can use randomize sop on points to create orient and pscale and copy to points will use it.