Shader with simple drop shadow

Unity Engine
1

I’m working on a 2D game that requires some drop shadow effects for some of the items in the background scenery.
I’ve been reading as much about Shaderlab as I can but still seem very lost.

Can someone point me in the right direction on how to make a simple drop shadow shader.
I’m using the Unlit/Transparent shader as the base as I use that for all my objects.

From what I understand… I should render my image in one pass…

Pass {
SetTexture [_MainTex] {
constantColor [_Color]
Combine Texture * constant, Texture * constant
}
}

Then add another pass with perhaps a vertex offset of some sort in some sort of shaded black?

How can I achieve this?

Thanks

2

It is possible with a post processing effect. Nvidia shader library has a sample to look at.

3

Hmm I’ve looked at their shaders… seems they need to be converted to work with Unity. Still trying to figure out how to do that.

4

Hey, just curious, did you manage to solve that issue ? I googled “drop shadow effect in unity” in google and your thread turned up, showing, I’m looking for the exact same thing :smile:
Maybe you could give a hint on how you solved this issue ?

5

I once wrote a tutorial about rendering drop shadows with a GLSL shader:
http://en.wikibooks.org/wiki/GLSL_Programming/Unity/Shadows_on_Planes

On Windows you have to start Unity with the -force-opengl command line argument to use GLSL shaders (see http://unity3d.com/support/documentation/Manual/Command%20Line%20Arguments.html )

(I guess you didn’t find this page because you included the word “effect” in your google search.)

6

Got here via Google as well. I guess no one’s written one via Shader Graph to help numpties like me yet!