Projective texturing using world coords

Hi



How can I project a texture on a model that has no texture maps using world coordinates.



I need something like this:

In addition to using texture coordinates that are built into the model, it is also possible to generate texture coordinates at runtime. Usually you would use this technique to achieve some particular effect, such as projective texturing…



Are there any examples I can take a look at?



Help&Advice appreciated



thanks…