Unity Color Lit shader

ColorLit.shader.cpp

Shader "Screw/Lit Color" {
	Properties {
		_Color ("Color", Color) = (1, 1, 1, 1)
	}
	SubShader {
		Tags { "RenderType"="Opaque" }
		LOD 200
		
		Pass {
			CGPROGRAM
						
			#pragma vertex vert 
			#pragma fragment frag
			
			struct VertexInput {
				half4 vertex : POSITION;
				half2 texcoord : TEXCOORD;
				half3 normal : NORMAL;
			}; 
			
			struct VertexOutput {
				half4 pos : SV_POSITION;
				half2 uv : TEXCOORD;
				half3 normalDir : NORMAL;
			};
			
			half4 _Color;
			half4 _LightColor0;

			VertexOutput vert (VertexInput i) {
				VertexOutput o;
				o.pos = mul(UNITY_MATRIX_MVP, i.vertex);
				o.uv = i.texcoord;
				o.normalDir = normalize(mul(float4( i.normal, 0.0 ), _World2Object ).xyz );
				return o;
			}
			
			half4 frag (VertexOutput i) : COLOR {				
				half3 lightDirection = normalize(-_WorldSpaceLightPos0.xyz);
				half4 color = _LightColor0 * max(0.0, dot(i.normalDir, lightDirection));
				color = color + UNITY_LIGHTMODEL_AMBIENT;
				return color * _Color;
			}					
			
			ENDCG
		}
		
	} 
	FallBack "Diffuse"
}