search

marcomusy / vedo

A python module for scientific analysis of 3D data based on VTK and Numpy
https://vedo.embl.es
MIT License
1.98k stars 257 forks source link

Suggestion: Returning intersection points too when return_cell_id is true #1103

Closed ManuGraiph closed 2 weeks ago

ManuGraiph commented 2 months ago

Hi Marco!

Would it be possible for the pointcloud method closest_point to also return the intersection coordinates when return_cell_id is True?

It's basically changing the line 1536 in pointcloud.py from

if return_cell_id:
    return int(cid)

To:

if return_cell_id:
    return int(cid),np.array(trgp)

And adding the corresponding placeholder wherever it's being called.

I've been using it in a couple projects but i basically have to change it every time vedo gets an update and risking breaking functionality somewhere else.

Thanks in advance!

marcomusy commented 2 months ago

Hi, i-m a bit hesitant on this because this is very widely used ... in principle it should not be a significant overhead to recover the point from the index with myarray[cid] ?

ManuGraiph commented 2 months ago

Well, you can get the element vertices that way, but the intersection is not always at the 'midpoint', it can be anywhere, so, if the cells are "big", it may be an issue.

The idea came to me cause i needed both the intersection point and the cell index and i was basically running the exact method twice just adding the return_cell_id arg.

But no worries!! If it's too big an issue i can just use the face index, assume the intersection is at the midpoint and work with that, no big deal :)! I was just asking in case the method was used very locally and you wouldn't need to change much of it.

Thanks!

marcomusy commented 2 months ago

Well, you can get the element vertices that way, but the intersection is not always at the 'midpoint', it can be anywhere, so, if the cells are "big", it may be an issue.

Yes you've got a very valid point .. I need to think if there is some way to make the change so that it is not disruptive of existing code and examples.

ManuGraiph commented 2 months ago

If it's too hard/complicated/bitchy, don't worry, i was asking just in case it was simple.

So far, in my library, i changed that line and like 1 or 2 more when it's used in the same file just adding a placeholder for the 2nd value in the unpack and haven't had any issue so far.

Thanks a lot!