Transparency / Diffuse with Vertex Color + Lighting

So I'm trying to get a shader to work that will act like the default Transparent/Diffuse shader, which is able to be lit by point lights - but also support accepting a vertex color to change the tint.

This is so I can have multiple objects with the same material but vary the tints slightly, and still have them be affected by lighting.

Here is a shader that is transparent and has the Vertex color, but isn't lit. Is it possible to modify this to be lit, or modify the Transparent/Diffuse shader to also accept vertex colors?

I'm very much a n00b with shader code.

Thanks!

Code (csharp):

1. Shader "Ferr/Unlit Transparent Textured Vertex Color" {
2.     Properties {
3.         _MainTex("Texture (RGBA)", 2D) = "white" {}
4.     }
5.     SubShader {
6.         Tags { "Queue"="Transparent" "RenderType"="Transparent"  }
7.         Blend SrcAlpha OneMinusSrcAlpha
8.  
9.         LOD 200
10.        
11.         Pass {
12.             CGPROGRAM
13.             #pragma vertex   vert
14.             #pragma fragment frag
15.             #include "UnityCG.cginc"
16.  
17.             sampler2D _MainTex;
18.             float4    _MainTex_ST;
19.  
20.             struct VS_OUT {
21.                 float4 position : SV_POSITION;
22.                 float4 color    : COLOR;
23.                 float2 uv       : TEXCOORD0;
24.             };
25.  
26.             VS_OUT vert (appdata_full input) {
27.                 VS_OUT result;
28.                 result.position = mul (UNITY_MATRIX_MVP, input.vertex);
29.                 result.uv       = TRANSFORM_TEX (input.texcoord, _MainTex);
30.                 result.color    = input.color;
31.  
32.                 return result;
33.             }
34.  
35.             half4 frag (VS_OUT input) : COLOR {
36.                 half4 color = tex2D(_MainTex, input.uv);
37.                 return color * input.color;
38.             }
39.             ENDCG
40.         }
41.     }
42. }

 

I'm not even sure if this is possible or practical, I'd like to be able to lighten/darken my 2d terrain layers, but still accept normal lighting. I suppose I can create an instance of each material at runtime and modify the colors, or just create separate materials for each shade, but then I won't be able to batch them.

Would a custom shader solve any of this, or is a vertex colored shader that accepts normal lighting simply not possible?

Thanks,
Jesse

 

Take a look at this page which implements a shader that handles multiple light sources:

http://en.wikibooks.org/wiki/Cg_Programming/Unity/Multiple_Lights

It should have the information you need. Also you can change the brightness of a texture by modifying the final calculated color for each pixel (like double it for brightness or half it to darken it).