Projecting world into sperical segment

vvvv beta question
1

hello,

I want to project a rotating earth on a transparent sperical segment. I use a patch that came with the demo of vvvv last year. rotation and everything works fine.

  1. I think I must project my renderer output onto a 3d world in v4 . right? where can I find a simple mapping example?

  2. my earth rotates in the x direction. (actually i ignore the tilted earth axis) Now, the user can use a slider to shift the earth between the booth polar ice caps. When I change the z rotation I must also change the y rotation to get the effect the user expects. is there a mathematical description anywhere to do this?

regards

2

Use map node to map the slider value to the rotation of the sphere. You may also add a rotation node to transform node to have desired tilt. Can you please explain a bit more if i get it wrong?

3

after a few days off i will try it again…

I want to map the world globe on the spherical segment, the real projector is positioned behind. how do I position the virtual projector? inside the world?

4

do you think of something like this projector-(ex9.effect) ??

5

no, i have real spherical segment, i will project a real world (or that part of it) into this transparent sperical segment.

by the way: the effect ist very cool!

6

Use projector node as indicated and use clockwise culling for the spherical segment

7

i put the projector behind my earth.
can i use a full 3d sphere for my earth? I think it should be possible to crop the segment with the near and far pane of the projector?!?

or should i make a real segment.

sorry for my stupid questions, I’m totally new to mapping.

8

With the clockwise culling you should be good to go as the front facing part would be invisible and you would only see the inner side.

9

where can i define the clockwise culling?

10

cull node

11

thank you, i got it.

now i map my trackball movement to the earth.