Opacity in Unity Shader

Question

I´m trying to make a shader which simulates a warp speed effect, and i think is almost done, only need to know what should i change in the code to make the tunnel effect completely opaque and not see anything behind the tunnel effect.

I have added an alpha slider to see if i can control opacity but still the same result at the end.

Code is here:

Shader "Warp Tunnel Distortion Opaque" {
Properties {
_TintColor ("Tint Color", Color) = (0.5,0.5,0.5,0.5)

_Speed("UV Speed", Float) = 1.0
_WiggleX("_WiggleX", Float) = 1.0
_WiggleY("_WiggleY", Float) = 1.0
_WiggleDist("Wiggle distance", Float) = 1.0

_Offset("Vertex offset", float) = 0

_TintColor("Tint", Color) = (1.0, 1.0, 1.0, 1.0)

_MainTex("Distortion map", 2D) = "" {}
_Dist("Distortion ammount", Float) = 10.0   

}

Category {
        Tags { "Queue"="Geometry" "RenderType"="Opaque" }
Cull Back Lighting Off ZWrite Off 
Fog { Color (0,0,0,0) }
ZTest LEqual

SubShader {


GrabPass {
        Name "BASE"
        Tags { "LightMode" = "Always" }
    }

    Pass {


        CGPROGRAM
        #pragma vertex vert
        #pragma fragment frag
        #pragma multi_compile_particles

        #include "UnityCG.cginc"

        sampler2D _MainTex;
        fixed4 _TintColor;

        struct appdata_t {
            float4 vertex : POSITION;
            fixed4 color : COLOR;
            float2 texcoord : TEXCOORD0;
            float4 normal : NORMAL;
        };

        struct v2f {
            float4 vertex : SV_POSITION;
            fixed4 color : COLOR;
            float2 texcoord : TEXCOORD0;
            float4 posWorld : TEXCOORD1;
            float4 uvgrab : TEXCOORD2;  
            float4 projPos : TEXCOORD3;

        };

        float4 _MainTex_ST;
        float _Speed;

        float _WiggleX, _WiggleY, _WiggleDist;
        float _Offset;
        float _Dist;

        sampler2D _CameraDepthTexture;
    float _InvFade;

    sampler2D _GrabTexture;
    float4 _GrabTexture_TexelSize;

        v2f vert (appdata_t v)
        {
            v2f o;
            o.posWorld = mul(unity_ObjectToWorld, v.vertex);
            v.vertex.xyz += normalize(v.normal.xyz) * _Offset;
            o.vertex = UnityObjectToClipPos(v.vertex);  
            o.vertex.x += sin(_Time.y * _WiggleX) * _WiggleDist;    
            o.vertex.y -= sin(_Time.y * _WiggleY) * _WiggleDist;        
            o.color = v.color;
            o.texcoord = TRANSFORM_TEX(v.texcoord,_MainTex);

            o.projPos = ComputeScreenPos (o.vertex);
            COMPUTE_EYEDEPTH(o.projPos.z);


            #if UNITY_UV_STARTS_AT_TOP
                float scale = -1.0;
            #else
                float scale = 1.0;
            #endif

            o.uvgrab.xy = (float2(o.vertex.x, o.vertex.y*scale) + o.vertex.w) * 0.5;
            o.uvgrab.zw = o.vertex.zw;

            return o;
        }



        fixed4 frag (v2f i) : SV_Target
        {

            i.texcoord.y += _Time.x * _Speed;

            float4 packedTex = tex2D(_MainTex, i.texcoord);

            float local1 = packedTex.z * 2.4;
            float2 local2 = packedTex.rg * 2.25;

            packedTex.rg = local1 * local2;

            half2 bump = UnpackNormal(packedTex).rg; 
            float2 offset = bump * _Dist * _GrabTexture_TexelSize.xy;
            i.uvgrab.xy = offset * i.uvgrab.z + i.uvgrab.xy;

            half4 col = tex2Dproj( _GrabTexture, UNITY_PROJ_COORD(i.uvgrab));   

            return col;
        }
        ENDCG 
    }
}   
}
}

Thank you in advance.

Draco18s no longer trusts SE Draco18s no longer trusts SE · Accepted Answer · 2017-09-29T16:15:56

Well if you want it completely opaque, that's easy.

Right before the return statement, just add:

col.a = 1;

If you want it to actually care about the alpha slider in the input color, then do this:

col.a = _TintColor.a;

In the first case, _TintColor isn't used at all (there are no other references to it besides its declaration, of which there are 2 at the top (you should remove one of them) and one inside the CGprogram block which links the first one to a property that can be used within the CGprogram).

If you actually want to tint things, you'll have to multiply the _TintColor with the computed color coming from the texture and effect. There are multiple ways of doing it, for example:

col.r *= _TintColor.r;
col.g *= _TintColor.g;
col.b *= _TintColor.b;

How you want to handle it is up to you.

Opacity in Unity Shader

1 Answers