an image as the background?

i intend to make a 3d model of a person’s head by taking as input his photograph from the front and the side. i am facing a problem in this: if i make a viewport then how do i make the picture or the photograph as the background and let the user mark some points on the photograph. i am taking a digitised photograph of the subject.

If I’ve understood your question you need to put a picture on the background and do some picking.
You then need to texture the picture on a quad (or quads if you want to do tiling) and draw it always facing the camera (billboarding).
Then you should use glUnproject or the Pick Matrix to get the pick coords.

You can find some usefull tutorials about Billboarding, Tiling and picking on Underground Mine at http://www.spinningkids.org/umine

Bye,
rIO

Interesting idea, I think you best solution would to billboard the picture. Perhapse, if you projected a mesh grid on the subjects head before you took the picture it may also help with finding points for the head.

Hey thanks rIO
but i am new to OpenGL, no idea what billboard is. anywise, i’ll see to it.
thanks for now!
Tarang

Originally posted by rIO:
[b]If I’ve understood your question you need to put a picture on the background and do some picking.
You then need to texture the picture on a quad (or quads if you want to do tiling) and draw it always facing the camera (billboarding).
Then you should use glUnproject or the Pick Matrix to get the pick coords.

You can find some usefull tutorials about Billboarding, Tiling and picking on Underground Mine at http://www.spinningkids.org/umine

Bye,
rIO[/b]

Hello Daddy
i plan to make a 3d wire frame model of this scanned in digitized image using NURBS. what is meant by billboarding apicture.
Thanks!
Tarang

Originally posted by GRanDaddY:
Interesting idea, I think you best solution would to billboard the picture. Perhapse, if you projected a mesh grid on the subjects head before you took the picture it may also help with finding points for the head.