Custom shader always reverts to fallback

Questions & Answers
1

Hi,

I have a custom shader that’s basically a copy of Unity’s built-in Transparent/Diffuse at this moment:

Shader "Custom/TransparentDiffuseSaturation" {
Properties {
	_Color ("Main Color", Color) = (1, 1, 1, 1)
	_MainTex ("Base (RGB)", 2D) = "white" {}
}

SubShader {
	Tags {"Queue"="Transparent" "IgnoreProjector"="True" "RenderType"="Transparent"}
	LOD 200

CGPROGRAM
#pragma surface surf Lambert alpha
		
sampler2D _MainTex;
fixed4 _Color;
		
struct Input {
	float2 uv_MainTex;
};
		
void surf (Input IN, inout SurfaceOutput o) {
	fixed4 c = tex2D(_MainTex, IN.uv_MainTex) * _Color;
	o.Albedo = c.rgb;
	o.Alpha = c.a;
}
ENDCG
} 

Fallback "Diffuse"
}

It works fine in the editor view, but only if the game is not running. As soon as I click “Play”, it reverts to the Fallback shader. Same thing happens in web and standalone builds.

The funny thing is, if I set Fallback to Transparent/Diffuse, it actually does fall back to Transparent/Diffuse. It looks like for some reason it just won’t execute the SubShader code.

What should I do to make it work?

2

This could be either a bug on part of the engine, or something extremely silly on my own part. Turns out it was the latter.

There is an option in Camera settings called Rendering Path. For reasons not clear to me (I don’t recall ever meddling with it) it was set to Vertex Lit, which is apparently not enough for surface shaders. I guess the shader wasn’t really falling back to Transparent/Diffuse, but to Transparent/Vertex Lit after all.

Changing the value to Forward fixed the issue for me.