Transforms and Junk

1. transforms to attribute matrix:

p@orient = quaternion(3@transform);
v@scale = cracktransform(0,0,2,set(0.0.0). 3@transform);

2. rotate packed fracture based on point + distance:

vector p1= set(@P.x, @P.y, @P.z);

vector crack1 = point(1, "P", 0);
vector crack2 = point(2, "P", 0);
vector p2 = crack1-p1;
vector p3 = crack2-p1;
float n = fit ( length ( p2 ), 0, ch("maxdist"), ch('mult'), 0 );
float n2 =  fit ( length ( p3 ), 0, ch("maxdist2"), ch('mult2'), 0 );

vector4 q0 = quaternion ( 0 );
vector4 q1 = sample_orientation_uniform ( rand ( @ptnum ) );
vector4 q2 = slerp ( q0, q1, n+n2 );
matrix3 xform = qconvert ( q2 );

setprimintrinsic ( 0, "transform", @ptnum, xform );

3. Blending spiral (end beg):

vector target = point(1, "P", @ptnum);
float blend = chramp("blendAlongSpiral", @curveu)*chf("multiplier");

@P = lerp(@P, target, blend);

4. Position copy via uv:

v@P = uvsample(1, "P", "uv", @P);

5. move near points together:

int near = nearpoint(1, @P);
vector target = point(1, "P", near);
@P = target;

6. Affect the scale of packed prims:

//vector scale = fit01(vector(rand(@primnum)), 0,1.46) *@growth;
vector scale = ch("scale");

matrix3 trn = primintrinsic(0, "transform", @primnum);
matrix scalem = maketransform(0, 0, {0,0,0}, {0,0,0}, scale, @P);
trn *= matrix3(scalem);
setprimintrinsic(0, "transform", @primnum, trn);