Resolved shadergraph performance worries: it generates shader with branches?

aren't branches slow on gpu?
surprised to find this jewel at the end of the fragment

return all(isfinite(surf.Diffuse_7)) ? half4(surf.Diffuse_7.x, surf.Diffuse_7.y, surf.Diffuse_7.z, 1.0) : float4(1.0f, 0.0f, 1.0f, 1.0f);

Spoiler: this is the full thing

Code (CSharp):

1. Shader "Custom Function"
2. {
3.     Properties
4.     {
5.         [NoScaleOffset]_BaseMap("BaseMap", 2D) = "white" {}
6.         [NoScaleOffset]_NormalMap("NormalMap", 2D) = "white" {}
7.         [HDR]_SpecColor("SpecColor", Color) = (1.135301, 1.135301, 1.135301, 0)
8.         _Smoothness("Smoothness", Float) = 0.5
9.         [HDR]Color_F5CA356F("SSS", Color) = (0.7264151, 0.3387442, 0.1473389, 0)
10.     }
11.  
12.     HLSLINCLUDE
13.     #include "Packages/com.unity.render-pipelines.core/ShaderLibrary/Common.hlsl"
14.     #include "Packages/com.unity.render-pipelines.core/ShaderLibrary/Packing.hlsl"
15.     #include "Packages/com.unity.render-pipelines.core/ShaderLibrary/NormalSurfaceGradient.hlsl"
16.     #include "Packages/com.unity.render-pipelines.core/ShaderLibrary/Color.hlsl"
17.     #include "Packages/com.unity.render-pipelines.core/ShaderLibrary/UnityInstancing.hlsl"
18.     #include "Packages/com.unity.render-pipelines.core/ShaderLibrary/EntityLighting.hlsl"
19.     #include "Packages/com.unity.shadergraph/ShaderGraphLibrary/ShaderVariables.hlsl"
20.     #include "Packages/com.unity.shadergraph/ShaderGraphLibrary/ShaderVariablesFunctions.hlsl"
21.     #include "Packages/com.unity.shadergraph/ShaderGraphLibrary/Functions.hlsl"
22.     #define SHADERGRAPH_PREVIEW 1
23.  
24.     CBUFFER_START(UnityPerMaterial)
25.     half4 _SpecColor;
26.     half _Smoothness;
27.     half4 Color_F5CA356F;
28.     CBUFFER_END
29.     TEXTURE2D(_BaseMap); SAMPLER(sampler_BaseMap); half4 _BaseMap_TexelSize;
30.     TEXTURE2D(_NormalMap); SAMPLER(sampler_NormalMap); half4 _NormalMap_TexelSize;
31.  
32.     struct SurfaceDescriptionInputs
33.     {
34.         float3 WorldSpaceNormal;
35.         float3 WorldSpaceViewDirection;
36.         float3 WorldSpacePosition;
37.     };
38.  
39.  
40.     // ddb8951f46b5bf7aa9aa154e10897ab5
41.     #include "Assets/art/shaders/CustomLighting.hlsl"
42.  
43.     struct SurfaceDescription
44.     {
45.         half3 Diffuse_7;
46.     };
47.  
48.     SurfaceDescription PopulateSurfaceData(SurfaceDescriptionInputs IN)
49.     {
50.         SurfaceDescription surface = (SurfaceDescription)0;
51.         half3 _CustomFunction_69DE6333_Diffuse_7;
52.         half3 _CustomFunction_69DE6333_Specular_8;
53.         AdditionalLights_half(half3 (0, 0, 0), 0, IN.WorldSpacePosition, IN.WorldSpaceNormal, IN.WorldSpaceViewDirection, _CustomFunction_69DE6333_Diffuse_7, _CustomFunction_69DE6333_Specular_8);
54.         surface.Diffuse_7 = _CustomFunction_69DE6333_Diffuse_7;
55.         return surface;
56.     }
57.  
58.     struct GraphVertexInput
59.     {
60.         float4 vertex : POSITION;
61.         float3 normal : NORMAL;
62.         UNITY_VERTEX_INPUT_INSTANCE_ID
63.     };
64.  
65.     GraphVertexInput PopulateVertexData(GraphVertexInput v)
66.     {
67.         return v;
68.     }
69.  
70.     ENDHLSL
71.  
72.     SubShader
73.     {
74.         Tags { "RenderType"="Opaque" }
75.         LOD 100
76.  
77.         Pass
78.         {
79.             HLSLPROGRAM
80.             #pragma vertex vert
81.             #pragma fragment frag
82.  
83.             struct GraphVertexOutput
84.             {
85.                 float4 position : POSITION;
86.                 float3 WorldSpacePosition : TEXCOORD0;
87.             float3 WorldSpaceNormal : TEXCOORD1;
88.             float3 WorldSpaceViewDirection : TEXCOORD2;
89.  
90.             };
91.  
92.             GraphVertexOutput vert (GraphVertexInput v)
93.             {
94.                 v = PopulateVertexData(v);
95.  
96.                 GraphVertexOutput o;
97.                 float3 positionWS = TransformObjectToWorld(v.vertex);
98.                 o.position = TransformWorldToHClip(positionWS);
99.                 float3 WorldSpacePosition = mul(UNITY_MATRIX_M,v.vertex).xyz;
100.             float3 WorldSpaceNormal = normalize(mul(v.normal,(float3x3)UNITY_MATRIX_I_M));
101.             float3 WorldSpaceViewDirection = _WorldSpaceCameraPos.xyz - mul(GetObjectToWorldMatrix(), float4(v.vertex.xyz, 1.0)).xyz;
102.                 o.WorldSpacePosition = WorldSpacePosition;
103.                 o.WorldSpaceNormal = WorldSpaceNormal;
104.                 o.WorldSpaceViewDirection = WorldSpaceViewDirection;
105.  
106.                 return o;
107.             }
108.  
109.             float4 frag (GraphVertexOutput IN ) : SV_Target
110.             {
111.                 float3 WorldSpacePosition = IN.WorldSpacePosition;
112.             float3 WorldSpaceNormal = IN.WorldSpaceNormal;
113.             float3 WorldSpaceViewDirection = IN.WorldSpaceViewDirection;
114.  
115.                 SurfaceDescriptionInputs surfaceInput = (SurfaceDescriptionInputs)0;
116.                 surfaceInput.WorldSpaceNormal = WorldSpaceNormal;
117.             surfaceInput.WorldSpaceViewDirection = WorldSpaceViewDirection;
118.             surfaceInput.WorldSpacePosition = WorldSpacePosition;
119.  
120.                 SurfaceDescription surf = PopulateSurfaceData(surfaceInput);
121.                 return all(isfinite(surf.Diffuse_7)) ? half4(surf.Diffuse_7.x, surf.Diffuse_7.y, surf.Diffuse_7.z, 1.0) : float4(1.0f, 0.0f, 1.0f, 1.0f);
122.  
123.             }
124.             ENDHLSL
125.         }
126.     }
127. }
128.  

Code (CSharp):

1. void MainLight_half(float3 WorldPos, out half3 Direction, out half3 Color, out half DistanceAtten, out half ShadowAtten)
2. {
3.     #if SHADERGRAPH_PREVIEW
4.     Direction = half3(0.5, 0.5, 0);
5.     Color = 1;
6.     DistanceAtten = 1;
7.     ShadowAtten = 1;
8.     #else
9.     #if SHADOWS_SCREEN
10.     half4 clipPos = TransformWorldToHClip(WorldPos);
11.     half4 shadowCoord = ComputeScreenPos(clipPos);
12.     #else
13.     half4 shadowCoord = TransformWorldToShadowCoord(WorldPos);
14.     #endif
15.     Light mainLight = GetMainLight(shadowCoord);
16.     Direction = mainLight.direction;
17.     Color = mainLight.color;
18.     DistanceAtten = mainLight.distanceAttenuation;
19.     ShadowAtten = mainLight.shadowAttenuation;
20.     #endif
21. }
22.  
23. void DirectSpecular_half(half3 Specular, half Smoothness, half3 Direction, half3 Color, half3 WorldNormal, half3 WorldView, out half3 Out)
24. {
25.     #if SHADERGRAPH_PREVIEW
26.     Out = 0;
27.     #else
28.     Smoothness = exp2(10 * Smoothness + 1);
29.     WorldNormal = normalize(WorldNormal);
30.     WorldView = SafeNormalize(WorldView);
31.     Out = LightingSpecular(Color, Direction, WorldNormal, WorldView, half4(Specular, 0), Smoothness);
32.     #endif
33. }
34.  
35. void AdditionalLights_half(half3 SpecColor, half Smoothness, half3 WorldPosition, half3 WorldNormal, half3 WorldView, out half3 Diffuse, out half3 Specular)
36. {
37.     half3 diffuseColor = 0;
38.     half3 specularColor = 0;
39.  
40.     #ifndef SHADERGRAPH_PREVIEW
41.     Smoothness = exp2(10 * Smoothness + 1);
42.     WorldNormal = normalize(WorldNormal);
43.     WorldView = SafeNormalize(WorldView);
44.     int pixelLightCount = GetAdditionalLightsCount();
45.     for (int i = 0; i < pixelLightCount; ++i)
46.     {
47.         Light light = GetAdditionalLight(i, WorldPosition);
48.         half3 attenuatedLightColor = light.color * (light.distanceAttenuation * light.shadowAttenuation);
49.         diffuseColor += LightingLambert(attenuatedLightColor, light.direction, WorldNormal);
50.         specularColor += LightingSpecular(attenuatedLightColor, light.direction, WorldNormal, WorldView, half4(SpecColor, 0), Smoothness);
51.     }
52.     #endif
53.  
54.     Diffuse = diffuseColor;
55.     Specular = specularColor;
56. }

 

This isn't a branch, it's a conditional move.

 

gotcha, thanks