3D points to 2D data?

Beginners
1

Hey guys,

I am searching for a way to convert a 3D point with XYZ values to 2D point with just XY values (scaling doesn’t matter).

So if I have, let’s say a sphere, in geometry, going to a render node - how can I take out just XY values in some sort of a operator? If the sphere is going back in Z axis, how to get the XY data from it? Is there a way?

I hope you guys understand me, and this would help me out really freakin much.
Pavel

2

Bump? Anyone?

3

Hi Pavel, I’m not sure I understand what you want to do.

are you wanting the xyz coordinates of the points of a sphere but without the z?

or are you wanting to render the sphere in 3D but have the 2D x,y location of each point when rendered?

4

Yeah it sort of hard to explain, I would get a screenshot of it but the computer is at school. Basically, if I have a sphere moving around in 3D space, and I want to put a 2D circle over it a follow it (sort of like the circle is aiming on the sphere).

Example how I tried solving it.
I made the sphere super small and green, and then converted the “render operator” where the sphere appeared to a TOP. From the top I got a pixel XY coordinates, and attached the circle to that. But it was way too heavy for the computer.

Then I also tried to use a formula to convert 3D location into 2D:
I tried to do the same thing as they do here:
[url]java - Perspective Projection: determine the 2D screen coordinates (x,y) of points in 3D space (x,y,z) - Stack Overflow

I hope you understand… I there a way?