Simple shader question...

Hello,

I was wondering if there is any way to edit a shader to always render on top of everything in the scene?

Similar to the Text shader.

Thanks a lot!!

BTW Right now I am trying to get the default additive shader to work.

Shader "Particles/Additive" {
Properties {
    _TintColor ("Tint Color", Color) = (0.5,0.5,0.5,0.5)
    _MainTex ("Particle Texture", 2D) = "white" {}
    _InvFade ("Soft Particles Factor", Range(0.01,3.0)) = 1.0
}

Category {
    Tags { "Queue"="Transparent" "IgnoreProjector"="True" "RenderType"="Transparent" }
    Blend SrcAlpha One
    AlphaTest Greater .01
    Blend SrcAlpha OneMinusSrcAlpha
    ColorMask RGB
    Cull Off Lighting Off ZWrite Off Fog { Mode Off }
    BindChannels {
        Bind "Color", color
        Bind "Vertex", vertex
        Bind "TexCoord", texcoord
    }

    // ---- Fragment program cards
    SubShader {
        Pass {

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

            #include "UnityCG.cginc"

            sampler2D _MainTex;
            float4 _TintColor;

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

            struct v2f {
                float4 vertex : POSITION;
                float4 color : COLOR;
                float2 texcoord : TEXCOORD0;
                #ifdef SOFTPARTICLES_ON
                float4 projPos : TEXCOORD1;
                #endif
            };

            float4 _MainTex_ST;

            v2f vert (appdata_t v)
            {
                v2f o;
                o.vertex = mul(UNITY_MATRIX_MVP, v.vertex);
                #ifdef SOFTPARTICLES_ON
                o.projPos = ComputeScreenPos (o.vertex);
                COMPUTE_EYEDEPTH(o.projPos.z);
                #endif
                o.color = v.color;
                o.texcoord = TRANSFORM_TEX(v.texcoord,_MainTex);
                return o;
            }

            sampler2D _CameraDepthTexture;
            float _InvFade;

            half4 frag (v2f i) : COLOR
            {
                #ifdef SOFTPARTICLES_ON
                float sceneZ = LinearEyeDepth (tex2Dproj(_CameraDepthTexture, UNITY_PROJ_COORD(i.projPos)).r);
                float partZ = i.projPos.z;
                float fade = saturate (_InvFade * (sceneZ-partZ));
                i.color.a *= fade;
                #endif

                return 2.0f * i.color * _TintColor * tex2D(_MainTex, i.texcoord);
            }
            ENDCG 
        }
    }   

    // ---- Dual texture cards
    SubShader {
        Pass {
            SetTexture [_MainTex] {
                constantColor [_TintColor]
                combine constant * primary
            }
            SetTexture [_MainTex] {
                combine texture * previous DOUBLE
            }
        }
    }

    // ---- Single texture cards (does not do color tint)
    SubShader {
        Pass {
            SetTexture [_MainTex] {
                combine texture * primary
            }
        }
    }
}
}

You should just be able to use z-testing:

ZTest Always