Shader "Custom/DissolveShader" {
    Properties {
        _MainTex ("Texture", 2D) = "white" {}
        _Color ("Color", Color) = (1,1,1,1)
        _DissolveAmount ("Dissolve Amount", Range(0, 1)) = 0
        _DissolveSpeed ("Dissolve Speed", Range(0, 1)) = 0.5
        _NoiseScale ("Noise Scale", Range(0, 1)) = 0.1
    }
 
    SubShader {
        Tags {"Queue"="Transparent" "RenderType"="Opaque"}
 
        Pass {
            CGPROGRAM
            #pragma vertex vert
            #pragma fragment frag
            #include "UnityCG.cginc"
 
            struct appdata {
                float4 vertex : POSITION;
                float2 uv : TEXCOORD0;
            };
 
            struct v2f {
                float2 uv : TEXCOORD0;
                float4 vertex : SV_POSITION;
            };
 
            sampler2D _MainTex;
            float4 _MainTex_ST;
            float4 _Color;
            float _DissolveAmount;
            float _DissolveSpeed;
            float _NoiseScale;
 
            v2f vert (appdata v) {
                v2f o;
                o.vertex = UnityObjectToClipPos(v.vertex);
                o.uv = TRANSFORM_TEX(v.uv, _MainTex);
                return o;
            }
 
            float4 frag (v2f i) : SV_Target {
                float4 col = tex2D(_MainTex, i.uv) * _Color;
                float dissolveValue = _DissolveAmount + _Time.y * _DissolveSpeed;
                float noiseValue = 1.0 - tex2D(_MainTex, i.uv * _NoiseScale + _Time.y * _DissolveSpeed).r;
                dissolveValue = max(0, min(1, dissolveValue + noiseValue));
                col.a *= dissolveValue;
                return col;
            }
            ENDCG
        }
    }
    FallBack "Diffuse"
}