TV screen shader: unlit shader with meta pass...possible?

Hello,

I'm using a movie for 'emission' map

...and would like to boost the 'emission' power...but if I do so the image itself is overexposed


Ideally, I would like to be able to use a 'unlit' shader (so that the screen is always perfectly displayed) AND use a meta pass with a intensity slider to be able to boost emission power over 1 !
Is this possible or is it a total non sense? (shader noob here ;-) )

Thanks!!

 

simple way, you could use a unlit shader to render your TV and use a second mesh to render your emission. The second mesh would be in a layer that is not rendered by your camera, this way you can crank up the emission and the TV would not change, only the light emitted.

more complex way, make a custom shader that changes the value only in the meta pass, look at the built in standard shader, it has a meta pass you could use.

 

Probably the best way, yeah.

 

Unfortunately, I'm new to all this (including Unity ) I've already this piece of code, just missing a slider to boost emission power over 1 ! (as one can do for 'emission' power in the standard shader)

Code (csharp):

1.  
2. Shader "Custom/metaPassShader"{
3.  
4.     Properties {
5.         _Color ("Color", Color)=(1,1,1,1)
6.         _MainTex ("Albedo (RGB)",2D)="white"{}
7.         _Glossiness ("Smoothness", Range(0,1))=0.5
8.         _Metallic ("Metallic", Range(0,1))=0.0
9.  
10.         _GIAlbedoColor ("Color Albedo (GI)", Color)=(1,1,1,1)
11.         _GIAlbedoTex ("Albedo (GI)",2D)="white"{}
12.     }
13.  
14.     SubShader {
15.     // ------------------------------------------------------------------
16.     // Extracts information for lightmapping, GI (emission, albedo, ...)
17.     // This pass is not used during regular rendering.
18.         Pass
19.         {
20.             Name "META"
21.             Tags {"LightMode"="Meta"}
22.             Cull Off
23.             CGPROGRAM
24.  
25.             #include"UnityStandardMeta.cginc"
26.  
27.             sampler2D _GIAlbedoTex;
28.             fixed4 _GIAlbedoColor;
29.             float4 frag_meta2 (v2f_meta i): SV_Target
30.             {
31.                 // We're interested in diffuse & specular colors
32.                 // and surface roughness to produce final albedo.
33.            
34.                 FragmentCommonData data = UNITY_SETUP_BRDF_INPUT (i.uv);
35.                 UnityMetaInput o;
36.                 UNITY_INITIALIZE_OUTPUT(UnityMetaInput, o);
37.                 fixed4 c = tex2D (_GIAlbedoTex, i.uv);
38.                 o.Albedo = fixed3(c.rgb * _GIAlbedoColor.rgb);
39.                 o.Emission = Emission(i.uv.xy);
40.                 return UnityMetaFragment(o);
41.             }
42.        
43.             #pragma vertex vert_meta
44.             #pragma fragment frag_meta2
45.             #pragma shader_feature _EMISSION
46.             #pragma shader_feature _METALLICGLOSSMAP
47.             #pragma shader_feature ___ _DETAIL_MULX2
48.             ENDCG
49.         }
50.    
51.         Tags {"IgnoreProjector"="True" "RenderType"="Opaque"}
52.         LOD 200
53.  
54.         CGPROGRAM
55.         // Physically-based Standard lighting model, and enable shadows on all light types
56.         #pragma surface surf Standard fullforwardshadows nometa
57.         // Use Shader model 3.0 target, to get nicer looking lighting
58.         #pragma target 3.0
59.  
60.         sampler2D _MainTex;
61.  
62.         struct Input {
63.             float2 uv_MainTex;
64.         };
65.    
66.         half _Glossiness;
67.         half _Metallic;
68.         fixed4 _Color;
69.    
70.         void surf (Input IN,inout SurfaceOutputStandard o){
71.             // Albedo comes from a texture tinted by color
72.             fixed4 c = tex2D (_MainTex, IN.uv_MainTex)* _Color;
73.             o.Albedo = c.rgb;
74.             // Metallic and smoothness come from slider variables
75.             o.Metallic = _Metallic;
76.             o.Smoothness = _Glossiness;
77.             o.Alpha = c.a;
78.         }
79.         ENDCG
80.     }
81.  
82.     FallBack "Diffuse"
83. }

 

is replacing
o.Emission = Emission(i.uv.xy);
by
o.Emission = Emission(i.uv.xy) * _SomeFloatValue;

and setting the _SomeFloatValue to somthing higher than 1 works?

 

YanVerde, thanks for your reply!

No, it doesn't!