Hey,
Im currently working on an adventure game using pre rendered backgrounds using a 3D mesh as a path for my character to walk around on. Im casting a blob shadow using a projector, but this only seems to be visable when the 3D mesh is rendered. I was wonding if anyone new of a way to have a shadow cast on a invisible object? From what I can tell it seem the projector needs something to project onto to be visable. 
Also attached a picture to demonstrate the problem.
Try using this shader on the mesh instead of deactivating its renderer.
the blob will not bend to the surface though it will always look as if the ground on which you stand was flat like the one of the original setup
so you might potentially want to prerender it all but none the less have the underground as a real model there too for the shadow to cast.
Thanks for the replies.
I’ve tried adding a transparent material to the mesh but the blob shadow is still not showing. I must be doing something wrong. I creaed a small transparent PNG 12x12, under the import settings I set it to RGBA Compressed PVRTC and assigned it to the texture slot on a transparent/diffuse material. Is this the corret process to create a transparent material? Sorry if its a noobish question, I’m still pretty new to unity.
I edited my post… try using the depth mask shader I linked to.
Works perfectly! Thanks! 
