Dissolving mesh with multiple materials attached

Graphics Shaders & Materials
1

Hello!
I’m trying to figure out how to dissolve quad with multiple materials attached.
Quad used as base for 2d background with 3 materials - first for sky texture, second for clouds texture and third for foreground texture. All 3 materials uses custom modified shader made from Unlit/Transparent shader with added Color field to control texture color and alpha.

Shader "Unlit/TransparentColor" {
Properties
{
    _MainTex ("Base (RGB) Trans (A)", 2D) = "white" {}
    _Color("Main Color", Color) = (1,1,1,1)
}

SubShader
{
    Tags
    {
        "Queue"="Transparent"
        "IgnoreProjector"="True"
        "RenderType"="Transparent"
        "PreviewType" = "Plane"
    }
    LOD 100
   
    Cull Off
    Lighting Off
    ZWrite Off
    Blend One OneMinusSrcAlpha
   
    Pass { 
        CGPROGRAM
            #pragma vertex vert
            #pragma fragment frag
            #pragma target 2.0
            #pragma multi_compile_fog
           
            #include "UnityCG.cginc"

            struct appdata_t {
                float4 vertex : POSITION;
                float4 color    : COLOR;
                float2 texcoord : TEXCOORD0;
                UNITY_VERTEX_INPUT_INSTANCE_ID
            };

            struct v2f {
                float4 vertex : SV_POSITION;
                fixed4 color : COLOR;
                float2 texcoord : TEXCOORD0;
                UNITY_FOG_COORDS(1)
                UNITY_VERTEX_OUTPUT_STEREO
            };

            fixed4 _Color;
            sampler2D _MainTex;
            float4 _MainTex_ST;
           
            v2f vert (appdata_t v)
            {
                v2f o;
                UNITY_SETUP_INSTANCE_ID(v);
                UNITY_INITIALIZE_VERTEX_OUTPUT_STEREO(o);
                o.vertex = UnityObjectToClipPos(v.vertex);
                o.texcoord = TRANSFORM_TEX(v.texcoord, _MainTex);
                o.color = v.color * _Color;
                UNITY_TRANSFER_FOG(o,o.vertex);
                return o;
            }
           
            fixed4 frag (v2f i) : SV_Target
            {
                fixed4 col = tex2D(_MainTex, i.texcoord) * i.color;
                col.rgb *= col.a;
                UNITY_APPLY_FOG(i.fogCoord, col);
                return col;
            }
        ENDCG
    }
}

}

Clouds animated by changing clouds material UV in simple script.

Now the problem: I want to dissolve whole background with all materials and I’m trying to change materials alpha to achieve this with script but in process foreground became semi-transparent and I can see clouds through foreground.

Example: Make Mockups, Logos, Videos and Designs in Seconds

Is there a way to dissolve this gameobject without clouds becoming visible through foreground while still animating clouds?

2

Yes, by using a single material & shader that can render all those layers at once.

Basically you want to make two duplicates of all lines with “_MainTex”, replacing MainTex with SkyTex and CloudTex for example. Then composite them together with lerp() functions.