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Get coordinates in 3D-Space

Hi vvvv guys!

I have two questions about 3D Geometry:

  1. I have a 3D-Box. I want to get the 8 xyz-coordinates of its 8 corners.
    I tried this via Mesh --> Vertex Buffer. Here I get every corner 3 times.

I understand why, but is there a node which gives me every corner only 1 time? So that i have only 8 xyz-Values? Or is there a way to avoid doubles of the vertexbuffer coordinates?

  1. As I understand it, the coordinates i get via vertex buffer are only in object space. But I’d like to get the corner coordinates of my box after a transformation (i.e. in World Space). For example: “where in 3d Space is Point 1 of my box after I turned the box 20° to the left around the y-axis.”

Is ther a node for this?

Thank you!

Concerning 2:
Have a look at ApplyTransform (Transform)

Concerning 1:
if you only need it for a box you can setslice your own subpatch, or a more manual approach with pointeditor

concerning 2:
maybe this could help you:
I wanted to know the xy coords of xyz skeleton points from kinect, see the patch from sitd.
ask if you have question

Skeleton pipet SITD.v4p (13.9 kB)

Thanks for your fast replies!

Question 2 is solved, the ApplyTransform Node did it perfectly!

ggml, your approach to Question 1 works, thanks for that.
But i think it would be great to find a more comfortable way, which works also for more complex objects. Something where you connect any mesh and then it returns a list of every vertex (without doubles).

Does anyone have another idea?

Sift (Value) should do it

Sift (Value) is almost what i was looking for. I connect the vertexbuffer Positions to both the sift input and filter. It returns the sliceindex where a value appears for the first time.

Only Problem: It compares every single value and not triplets (xyz).
Any Idea how to do that?

Thanks.

Hi
I am not on Windows right now but since I don t remember any bin size pin on Sift you can probably just de-vectorize (vector 3d split), send to 3 sift nodes and compare the result but I do agree that there should be a more “geometrical” way to get what you want.
S.

Just to complete this thread:

Clean (Spreads BinSize) by @kalle does the Job concerning question 1.

Download here:
vvvv.org/tiki-download_file.php?fileId=1502