3D points to 2D data?

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

Bump? Anyone?

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?

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?