PlanetShader

//ShaderGraph converted from
//https://www.youtube.com/watch?v=QN39W020LqU&index=2&t=0s&list=PLFt_AvWsXl0cONs3T0By4puYy6GM22ko8
//All creds to Sebastian Lague



Shader "PlanetOwn"
{
    Properties
    {
        _elevationMinMax("Elevation", Vector) = (0,1,0,0)
        _texture("Texture", 2D) = "white" {}
        _smoothness("Smoothness", Float) = 0

    }
    SubShader
    {
        Tags { "RenderType"="Opaque" }
        LOD 100

        Pass
        {
            CGPROGRAM
            #pragma vertex vert
            #pragma fragment frag
            // make fog work
            #pragma multi_compile_fog

            #include "UnityCG.cginc"

            struct appdata
            {
                float4 vertex : POSITION;
                float2 uv : TEXCOORD0;
            };

            struct v2f
            {
                float2 uv : TEXCOORD0;
                UNITY_FOG_COORDS(1)
                float4 vertex : SV_POSITION;
            };

            sampler2D _texture;
            float2 _elevationMinMax;
            float4 _texture_ST;

            v2f vert (appdata v)
            {
                v2f o;
                o.vertex = UnityObjectToClipPos(v.vertex);
                o.uv = TRANSFORM_TEX(v.uv, _texture);
                UNITY_TRANSFER_FOG(o,o.vertex);
                return o;
            }

            float Inverse_lerp(float a, float b, float value)
            {
                return (value -a)/(b-a);
            }

            fixed4 frag (v2f i) : SV_Target
            {
                // sample the texture
            float node_2 = Inverse_lerp(_elevationMinMax.r, 0, i.uv.g);
            float node_1 = floor(node_2);


            float2 uvt = float2(
                    (
                        (
                            lerp(
                                0,
                                0.5,
                                Inverse_lerp(_elevationMinMax.r, 0, i.uv.g)
                            )

                        *
                            (
                                floor(
                                    Inverse_lerp(_elevationMinMax.r, 0, i.uv.g)
                                )
                                -
                                1
                            )
                        )
                    +
                        floor(
                            Inverse_lerp(_elevationMinMax.r, 0, i.uv.g)
                        )
                        *
                        lerp(0, 1,
                            Inverse_lerp(0, _elevationMinMax.g, i.uv.g)
                        )
                    )
                ,
                    i.uv.r);


            fixed3 col = tex2D(_texture, uvt);

                // apply fog
                //UNITY_APPLY_FOG(i.fogCoord, col);
                return fixed4(col.r, col.g, col.b, 1);
            }
            ENDCG
        }
    }
}