How make a standard surface shader which use ambient light?

I am using a surface shader with standard illumination and it just ignore ambient light, it doesnt happen when i use the Standard shader unity provides

Code (CSharp):

1. Shader "Custom/CustomShader" {
2.     Properties {
3.         _Color ("Color", Color) = (1,1,1,1)
4.         _MainTex ("Albedo (RGB)", 2D) = "white" {}
5.         _BumpMap("Bumpmap", 2D) = "bump" {}
6.         _Glossiness ("Smoothness", Range(0,1)) = 0.5
7.         _Metallic ("Metallic", Range(0,1)) = 0.0
8.     }
9.     SubShader {
10.         Tags { "RenderType"="Opaque" }
11.         LOD 200
12.  
13.         CGPROGRAM
14.         // Physically based Standard lighting model, and enable shadows on all light types
15.         #pragma surface surf Standard fullforwardshadows
16.  
17.         // Use shader model 3.0 target, to get nicer looking lighting
18.         #pragma target 3.0
19.  
20.         sampler2D _MainTex;
21.         sampler2D _BumpMap;
22.  
23.         struct Input {
24.             float2 uv_MainTex;
25.             float2 uv_BumpMap;
26.         };
27.  
28.         half _Glossiness;
29.         half _Metallic;
30.         fixed4 _Color;
31.  
32.         void surf (Input IN, inout SurfaceOutputStandard o) {
33.             // Albedo comes from a texture tinted by color
34.             fixed4 c = tex2D (_MainTex, IN.uv_MainTex) * _Color;
35.             o.Albedo = c.rgb;
36.             // Metallic and smoothness come from slider variables
37.             o.Metallic = _Metallic;
38.             o.Normal = UnpackNormal(tex2D(_BumpMap, IN.uv_BumpMap));
39.             o.Smoothness = _Glossiness;
40.             o.Alpha = c.a;
41.         }
42.         ENDCG
43.     }
44.     FallBack "Diffuse"
45. }
46.  

 

try this pragma...
#pragma surface surf Lambert

 

It doesnt work, needs to be Standard to get the metallic and smoothness

 

you asked about ambient light. that pragma does work with ambient light... at least it does in my shaders, but I'm making shaders for mobile, So I'm not using metallic and smoothness.

Can you start from the shader unity provides, and modify that ? or look at the differences in tags, pragma or and included files.

 

yes i could try with the unity standard and modify but dont know how difficult it will be and i wanted to know why with the standard lighting model it doesnt have ambient light