animate vertices in SOP

[katisss]

hi,

nob question:

what is the fastet way to animate vertices on a deforming mesh in a sop to my polys?

Rebuilding the mesh is way to slow..

I read the data from a file but are cluesless about how to apply it

any help would be appreciated..

i just found this, is this what i do?

Phandle = gdp->getAttribute(GEO_POINT_DICT, "P");

for (i = 0; i < npts; i++)

{

Phandle.setElement(gdp->points()(i));

Pvalue = Phandle.getV4();

Pvalue.y() = sin(Pvalue.x()*.2 + Pvalue.z()*.3 + frame);

Phandle.setV4(Pvalue);

}

This is my first sop so i am happy with any suggestion for architecture.

Better make it 2 sops: 1 for building and a deformer?

Edited February 18, 2010 by katisss

[edward]

You can just override SOP_Node::shouldResetGeoToEmpty() to return false, then your gdp will be preserved across cooks (as long as it is still cached). Then can probably do some logic like this:

- Check if gdp is empty, if it is then build the geometry. If it's not empty, then we have already built our geometry.

- Update the point positions

[edward]

PS. If you end up splitting it into two SOPs (not a bad usability idea), then for your deformer, use SOP_Node::duplicateChangedSource() to copy the geometry. That function will be smart enough to reuse old geometry when it can.(and if it can't, a full copy will be done.)