I am trying to write a two pass standard shader. I have found examples with older shaders, I want to use Unity 5.4 beta and try to use the built-in shader to match all of the other objects in the scene. It is easy to break the standard shader, especially because I am not good with writing shaders to begin with. Usually I can find a shader, tweak a couple of things and I’m good.
I’m stuck and don’t know where to start! I have narrowed down that what I probably want is a two pass shader where one pass is for front faces, and the other for back faces. The front faces I want to be rendered exactly as the standard shader. The back faces I want to use a transparent shader, either with an alpha value or a texture with an alpha.
Here is a screen shot of what I am after [Note the model has normals reversed, meaning the interior is where this is supposed to be viewed, but as I the viewer exits the interior, I want the exterior to be visible as a grid]:
Can someone explain to me, where would I put the second shader? Here is the standard shader I am trying to work with:
Standard Shader :
Shader “Standard”
{
Properties
{
_Color(“Color”, Color) = (1,1,1,1)
_MainTex(“Albedo”, 2D) = “white” {}
_Cutoff(“Alpha Cutoff”, Range(0.0, 1.0)) = 0.5
_Glossiness(“Smoothness”, Range(0.0, 1.0)) = 0.5
_GlossMapScale(“Smoothness Scale”, Range(0.0, 1.0)) = 1.0
[Enum(Metallic Alpha,0,Albedo Alpha,1)] _SmoothnessTextureChannel (“Smoothness texture channel”, Float) = 0
[Gamma] _Metallic(“Metallic”, Range(0.0, 1.0)) = 0.0
_MetallicGlossMap(“Metallic”, 2D) = “white” {}
[ToggleOff] _SpecularHighlights(“Specular Highlights”, Float) = 1.0
[ToggleOff] _GlossyReflections(“Glossy Reflections”, Float) = 1.0
_BumpScale(“Scale”, Float) = 1.0
_BumpMap(“Normal Map”, 2D) = “bump” {}
_Parallax (“Height Scale”, Range (0.005, 0.08)) = 0.02
_ParallaxMap (“Height Map”, 2D) = “black” {}
_OcclusionStrength(“Strength”, Range(0.0, 1.0)) = 1.0
_OcclusionMap(“Occlusion”, 2D) = “white” {}
_EmissionColor(“Color”, Color) = (0,0,0)
_EmissionMap(“Emission”, 2D) = “white” {}
_DetailMask(“Detail Mask”, 2D) = “white” {}
_DetailAlbedoMap(“Detail Albedo x2”, 2D) = “grey” {}
_DetailNormalMapScale(“Scale”, Float) = 1.0
_DetailNormalMap(“Normal Map”, 2D) = “bump” {}
[Enum(UV0,0,UV1,1)] _UVSec (“UV Set for secondary textures”, Float) = 0
// Blending state
[HideInInspector] _Mode (“__mode”, Float) = 0.0
[HideInInspector] _SrcBlend (“__src”, Float) = 1.0
[HideInInspector] _DstBlend (“__dst”, Float) = 0.0
[HideInInspector] _ZWrite (“__zw”, Float) = 1.0
}
CGINCLUDE
#define UNITY_SETUP_BRDF_INPUT MetallicSetup
ENDCG
SubShader
{
Tags { “RenderType”=“Opaque” “PerformanceChecks”=“False” }
LOD 300
// ------------------------------------------------------------------
// Base forward pass (directional light, emission, lightmaps, …)
Pass
{
Name “FORWARD”
Tags { “LightMode” = “ForwardBase” }
Blend [_SrcBlend] [_DstBlend]
ZWrite [_ZWrite]
CGPROGRAM
#pragma target 3.0
// -------------------------------------
#pragma shader_feature _NORMALMAP
#pragma shader_feature _ _ALPHATEST_ON _ALPHABLEND_ON _ALPHAPREMULTIPLY_ON
#pragma shader_feature _EMISSION
#pragma shader_feature _METALLICGLOSSMAP
#pragma shader_feature ___ _DETAIL_MULX2
#pragma shader_feature _ _SMOOTHNESS_TEXTURE_ALBEDO_CHANNEL_A
#pragma shader_feature _ _SPECULARHIGHLIGHTS_OFF
#pragma shader_feature _ _GLOSSYREFLECTIONS_OFF
#pragma shader_feature _PARALLAXMAP
#pragma multi_compile_fwdbase
#pragma multi_compile_fog
#pragma vertex vertBase
#pragma fragment fragBase
#include “UnityStandardCoreForward.cginc”
ENDCG
}
// ------------------------------------------------------------------
// Additive forward pass (one light per pass)
Pass
{
Name “FORWARD_DELTA”
Tags { “LightMode” = “ForwardAdd” }
Blend [_SrcBlend] One
Fog { Color (0,0,0,0) } // in additive pass fog should be black
ZWrite Off
ZTest LEqual
CGPROGRAM
#pragma target 3.0
// -------------------------------------
#pragma shader_feature _NORMALMAP
#pragma shader_feature _ _ALPHATEST_ON _ALPHABLEND_ON _ALPHAPREMULTIPLY_ON
#pragma shader_feature _METALLICGLOSSMAP
#pragma shader_feature _ _SMOOTHNESS_TEXTURE_ALBEDO_CHANNEL_A
#pragma shader_feature _ _SPECULARHIGHLIGHTS_OFF
#pragma shader_feature ___ _DETAIL_MULX2
#pragma shader_feature _PARALLAXMAP
#pragma multi_compile_fwdadd_fullshadows
#pragma multi_compile_fog
#pragma vertex vertAdd
#pragma fragment fragAdd
#include “UnityStandardCoreForward.cginc”
ENDCG
}
// ------------------------------------------------------------------
// Shadow rendering pass
Pass {
Name “ShadowCaster”
Tags { “LightMode” = “ShadowCaster” }
ZWrite On ZTest LEqual
CGPROGRAM
#pragma target 3.0
// -------------------------------------
#pragma shader_feature _ _ALPHATEST_ON _ALPHABLEND_ON _ALPHAPREMULTIPLY_ON
#pragma multi_compile_shadowcaster
#pragma vertex vertShadowCaster
#pragma fragment fragShadowCaster
#include “UnityStandardShadow.cginc”
ENDCG
}
// ------------------------------------------------------------------
// Deferred pass
Pass
{
Name “DEFERRED”
Tags { “LightMode” = “Deferred” }
CGPROGRAM
#pragma target 3.0
#pragma exclude_renderers nomrt
// -------------------------------------
#pragma shader_feature _NORMALMAP
#pragma shader_feature _ _ALPHATEST_ON _ALPHABLEND_ON _ALPHAPREMULTIPLY_ON
#pragma shader_feature _EMISSION
#pragma shader_feature _METALLICGLOSSMAP
#pragma shader_feature _ _SMOOTHNESS_TEXTURE_ALBEDO_CHANNEL_A
#pragma shader_feature _ _SPECULARHIGHLIGHTS_OFF
#pragma shader_feature ___ _DETAIL_MULX2
#pragma shader_feature _PARALLAXMAP
#pragma multi_compile ___ UNITY_HDR_ON
#pragma multi_compile LIGHTMAP_OFF LIGHTMAP_ON
#pragma multi_compile DIRLIGHTMAP_OFF DIRLIGHTMAP_COMBINED DIRLIGHTMAP_SEPARATE
#pragma multi_compile DYNAMICLIGHTMAP_OFF DYNAMICLIGHTMAP_ON
#pragma vertex vertDeferred
#pragma fragment fragDeferred
#include “UnityStandardCore.cginc”
ENDCG
}
// ------------------------------------------------------------------
// Extracts information for lightmapping, GI (emission, albedo, …)
// This pass it not used during regular rendering.
Pass
{
Name “META”
Tags { “LightMode”=“Meta” }
Cull Off
CGPROGRAM
#pragma vertex vert_meta
#pragma fragment frag_meta
#pragma shader_feature _EMISSION
#pragma shader_feature _METALLICGLOSSMAP
#pragma shader_feature _ _SMOOTHNESS_TEXTURE_ALBEDO_CHANNEL_A
#pragma shader_feature ___ _DETAIL_MULX2
#include “UnityStandardMeta.cginc”
ENDCG
}
}
SubShader
{
Tags { “RenderType”=“Opaque” “PerformanceChecks”=“False” }
LOD 150
// ------------------------------------------------------------------
// Base forward pass (directional light, emission, lightmaps, …)
Pass
{
Name “FORWARD”
Tags { “LightMode” = “ForwardBase” }
Blend [_SrcBlend] [_DstBlend]
ZWrite [_ZWrite]
CGPROGRAM
#pragma target 2.0
#pragma shader_feature _NORMALMAP
#pragma shader_feature _ _ALPHATEST_ON _ALPHABLEND_ON _ALPHAPREMULTIPLY_ON
#pragma shader_feature _EMISSION
#pragma shader_feature _METALLICGLOSSMAP
#pragma shader_feature _ _SMOOTHNESS_TEXTURE_ALBEDO_CHANNEL_A
#pragma shader_feature _ _SPECULARHIGHLIGHTS_OFF
#pragma shader_feature _ _GLOSSYREFLECTIONS_OFF
// SM2.0: NOT SUPPORTED shader_feature ___ _DETAIL_MULX2
// SM2.0: NOT SUPPORTED shader_feature _PARALLAXMAP
#pragma skip_variants SHADOWS_SOFT DIRLIGHTMAP_COMBINED DIRLIGHTMAP_SEPARATE
#pragma multi_compile_fwdbase
#pragma multi_compile_fog
#pragma vertex vertBase
#pragma fragment fragBase
#include “UnityStandardCoreForward.cginc”
ENDCG
}
// ------------------------------------------------------------------
// Additive forward pass (one light per pass)
Pass
{
Name “FORWARD_DELTA”
Tags { “LightMode” = “ForwardAdd” }
Blend [_SrcBlend] One
Fog { Color (0,0,0,0) } // in additive pass fog should be black
ZWrite Off
ZTest LEqual
CGPROGRAM
#pragma target 2.0
#pragma shader_feature _NORMALMAP
#pragma shader_feature _ _ALPHATEST_ON _ALPHABLEND_ON _ALPHAPREMULTIPLY_ON
#pragma shader_feature _METALLICGLOSSMAP
#pragma shader_feature _ _SMOOTHNESS_TEXTURE_ALBEDO_CHANNEL_A
#pragma shader_feature _ _SPECULARHIGHLIGHTS_OFF
#pragma shader_feature ___ _DETAIL_MULX2
// SM2.0: NOT SUPPORTED shader_feature _PARALLAXMAP
#pragma skip_variants SHADOWS_SOFT
#pragma multi_compile_fwdadd_fullshadows
#pragma multi_compile_fog
#pragma vertex vertAdd
#pragma fragment fragAdd
#include “UnityStandardCoreForward.cginc”
ENDCG
}
// ------------------------------------------------------------------
// Shadow rendering pass
Pass {
Name “ShadowCaster”
Tags { “LightMode” = “ShadowCaster” }
ZWrite On ZTest LEqual
CGPROGRAM
#pragma target 2.0
#pragma shader_feature _ _ALPHATEST_ON _ALPHABLEND_ON _ALPHAPREMULTIPLY_ON
#pragma skip_variants SHADOWS_SOFT
#pragma multi_compile_shadowcaster
#pragma vertex vertShadowCaster
#pragma fragment fragShadowCaster
#include “UnityStandardShadow.cginc”
ENDCG
}
// ------------------------------------------------------------------
// Extracts information for lightmapping, GI (emission, albedo, …)
// This pass it not used during regular rendering.
Pass
{
Name “META”
Tags { “LightMode”=“Meta” }
Cull Off
CGPROGRAM
#pragma vertex vert_meta
#pragma fragment frag_meta
#pragma shader_feature _EMISSION
#pragma shader_feature _METALLICGLOSSMAP
#pragma shader_feature _ _SMOOTHNESS_TEXTURE_ALBEDO_CHANNEL_A
#pragma shader_feature ___ _DETAIL_MULX2
#include “UnityStandardMeta.cginc”
ENDCG
}
}
FallBack “VertexLit”
CustomEditor “StandardShaderGUI”
}