Vertex colors as blend factors

Unity Engine
1 
void surf(Input IN, inout SurfaceOutputStandard o)
        {
            // Albedo comes from a texture tinted by color
            float4 c = IN.color;
            if (IN.color.g > 0)
            {
                c = tex2D(_Rock, IN.uv_Gas).rgb;
            }
            if (IN.color.b > 0)
            {
                c = tex2D(_Snow, IN.uv_Gas).rgb;
            }

            o.Albedo = c.rgb;
            // Metallic and smoothness come from slider variables
            o.Metallic = _Metallic;
            o.Smoothness = _Glossiness;
            o.Alpha = c.a;
        }

I am using the preceeding shader function to try to do terrain splatting with vertex colors as the blend factors. However, the textures aren’t showing the terrain is colored green and blue. I am confused as to why the conditions are never true when clearly they should as the color is either green == 1 or blue == 1. Any ideas?

2

found the issue apparently > 0 caused .g to be converted to an int rather than the 0 which was what I expected to happen.

so its

if(IN.color.g > 0.0) instead