cutting an object along it s silhouette.

i m looking for a way to cut an object along it s silhouette. so as to project the silhouette along an other object. maybe it s possible to convert freestyle silhouette line into edge?
thanks
dagobert

http://wiki.blender.org/index.php/Doc:2.6/Manual/Modeling/Meshes/Editing/Subdividing/Knife_Subdivide#Knife_Project

Knife projection is not the tool. It do not cut an object a long it’s silhouette based on the point of view. it s usually a fonction you get un nurbs software.

The boolean modifier may well help you here. http://wiki.blender.org/index.php/Doc:2.6/Manual/Modifiers/Generate/Booleans