How to cast shadows on transparent object

Hi there.

I'm currently trying to cast a shadow into a transparent object but it just doesn't work. I've found some discussions about this in the forum and I read there that Unity simply doesn't support this but they are from years ago and someone wrote that at some point after Unity 5 the team will work on this feature so... is there any way to cast shadows on transparent objects now? or any workaround?

Thanks!

 

There is a shader in the Wikitude package for doing just that:

Code (CSharp):

1. Shader "Custom/Transparent Shadow Receiver" {
2. Properties {
3. }
4. SubShader {
5.     Tags {"Queue"="AlphaTest" "IgnoreProjector"="True" "RenderType"="TransparentCutout"}
6.     LOD 200
7.     ZWrite Off
8.     Blend Zero SrcColor
9. CGPROGRAM
10. #pragma surface surf ShadowOnly alphatest:_Cutoff
11. fixed4 _Color;
12. struct Input {
13.     float2 uv_MainTex;
14. };
15. inline fixed4 LightingShadowOnly (SurfaceOutput s, fixed3 lightDir, fixed atten)
16. {
17.     fixed4 c;
18.     c.rgb = s.Albedo * atten;
19.     c.a = s.Alpha;
20.     return c;
21. }
22. void surf (Input IN, inout SurfaceOutput o) {
23.     o.Albedo = 1;
24.     o.Alpha = 1;
25. }
26. ENDCG
27. }
28. Fallback "Transparent/Cutout/VertexLit"
29. }

 

hi, I tried this using a cube and the shadow is working good but the cube seems to have some sort of a weird blend with my transparent background and the line is visible. Any solution?