Shadows on a transparent material/mesh?

(Gilles38) #1

Hi all,
I know it sounds a bit weird but is it possible to cast shadows on a transparent material/mesh ?
I'd like to have a non-visible/transparent ground with shadows of objects casting on it...

Light shadow problem
(Dark Minaz) #2

While you can't do it with a transparent ground you could go with a "cheat"

simply have a extra material for the floor,with a bit of a falloff and make sure your floor got the same color than your background :slight_smile:
shadows on a 100% transparent object isn't possible as far as i am aware

(Gilles38) #3

Thank you @dark_minaz,
Nice workaround indeed.
I was looking for a way to make screeshots with full transparency, yet still keeping shadows on the transparent ground... I am not surprised this not possible though. The only way is probably to put a white background and ground as you suggest and then remove both on the final screenshot.
Thank you for your help

(Gilles38) #4

Hi again @dark_minaz,
just to complete this, I just found a topic on this forum about the so called shadow caster mentionned by @delicious, which looks like what I am looking for I think and has been implemented in Blender (latest version, 2.78c)

So I hope it will come soon or later on Sketchfab.

(Dark Minaz) #5

Oh yeah offline it is possible, i was just thinking in sketchfab :slight_smile:
maya can set planes to be non rendered but still recieve shadows.

But in a web application it is hard to do without making it behave wrong for other users (for example with poly plane grass, it would totally mess with those cards then)

Guess if you really want it just as screenshot you might have to make a shadow by hand in photoshop currently :slight_smile:

(Gilles38) #6

OK thank you, I didn't make the distinction between offline and online. Missing some basic knowledge obviously...
Anyway, I agree with you that image modification is the simplest way in my case.
Thank you