Question DX11-specific HLSL syntax (for StructuredBuffers) don't work in surface shaders on android

I can't get the following code to works on android. I want to use StructuredBuffers in a surface shader.

I tried a simple test, without StructuredBuffer:

Code (CSharp):

1. Shader "Custom/Test"
2. {
3.     Properties
4.     {
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.         SubShader
11.         {
12.             Tags { "RenderType" = "Opaque" }
13.             LOD 200
14.  
15.             CGPROGRAM
16.             // Physically based Standard lighting model, and enable shadows on all light types
17.             #pragma surface surf Standard fullforwardshadows
18.  
19.             // Use shader model 3.0 target, to get nicer looking lighting
20.             #pragma target 5.0
21.  
22.         sampler2D _MainTex;
23.  
24.         struct Input
25.         {
26.             float2 uv_MainTex;
27.         };
28.  
29.         half _Glossiness;
30.         half _Metallic;
31.         fixed4 _Color;
32.  
33.  
34.         void surf (Input IN, inout SurfaceOutputStandard o)
35.         {
36.             fixed4 c = fixed4(1, 0, 0, 1);
37.          
38. #ifdef SHADER_API_D3D11
39.            c = fixed4(0, 1, 0, 1);
40. #endif
41.        
42.             o.Albedo = c.rgb;
43.             // Metallic and smoothness come from slider variables
44.             o.Metallic = _Metallic;
45.             o.Smoothness = _Glossiness;
46.             o.Alpha = c.a;
47.         }
48.         ENDCG
49.     }
50.     FallBack "Diffuse"
51. }

In Editor the plane will be blue, but on mobile it remains red.

Another test:

Code (CSharp):

1.  
2. Shader "Custom/Test2"
3. {
4.     Properties
5.     {
6.         _Color ("Color", Color) = (1,1,1,1)
7.         _MainTex ("Albedo (RGB)", 2D) = "white" {}
8.         _Glossiness("Smoothness", Range(0,1)) = 0.5
9.         _Metallic("Metallic", Range(0,1)) = 0.0
10.     }
11.         SubShader
12.         {
13.             Tags { "RenderType" = "Opaque" }
14.             LOD 200
15.  
16.             CGPROGRAM
17.             // Physically based Standard lighting model, and enable shadows on all light types
18.             #pragma surface surf Standard fullforwardshadows
19.  
20.             // Use shader model 3.0 target, to get nicer looking lighting
21.             #pragma target 5.0
22.  
23. #ifdef SHADER_API_D3D11
24.             StructuredBuffer<float> test;
25. #endif
26.  
27.         sampler2D _MainTex;
28.  
29.         struct Input
30.         {
31.             float2 uv_MainTex;
32.         };
33.  
34.         half _Glossiness;
35.         half _Metallic;
36.         fixed4 _Color;
37.  
38.  
39.         void surf (Input IN, inout SurfaceOutputStandard o)
40.         {
41.             fixed4 c = fixed4(1, 0, 0, 1);
42.          
43. #ifdef SHADER_API_D3D11
44.             if (test[0] == 0)
45.                 c = fixed4(0, 1, 0, 1);
46.             else if (test[0] == 1)
47.                 c = fixed4(0, 0, 1, 1);
48. #endif
49.        
50.             o.Albedo = c.rgb;
51.             // Metallic and smoothness come from slider variables
52.             o.Metallic = _Metallic;
53.             o.Smoothness = _Glossiness;
54.             o.Alpha = c.a;
55.         }
56.         ENDCG
57.     }
58.     FallBack "Diffuse"
59. }
60.  

Same problem, in Editor- it will get color green or blue in function of value in StructuredBuffer, but on android it remains red.

Code (CSharp):

1.  
2. public class TestD11Api : MonoBehaviour
3. {
4.     float[] buffer;
5.     ComputeBuffer test;
6.     // Start is called before the first frame update
7.     void Start()
8.     {
9.         test = new ComputeBuffer(1, sizeof(float));
10.         buffer = new float[1];
11.         buffer[0] = 1.0f;
12.         test.SetData(buffer);
13.  
14.         GetComponent<MeshRenderer>().material.SetBuffer("test", test);
15.  
16.         Debug.Log("Support compute shaders : " + SystemInfo.supportsComputeShaders);
17.     }
18. }
19.  

One more thing, the android device is S6 with OpenGL ES 3.2 and support compute shaders. On the other hand if do a vert&frag shader then StructuredBuffer works inclusive on android.

I tried with 5.0 target model, but I want to use them in 3.5.

 

up

 

@aleksandrk I was thinking that Unity surface shader's interpreter transforms D3D11 specific HLSL syntax in something that is understandable by target device API, considering that StructuredBuffer works in Unlit shaders on Android.

So, how can I can get StructuredBuffers to work in surface shaders on Android and iOS? Or if I can't, what alternatives I have for it? I want an array with unknown size before runtime, I have many instances of the same shader with different sizes of array and don't want to waste memory defining all instances with a maximum size and also to manage all the time that maximum manually.

 

Code (CSharp):

1. Shader "Custom/Test2"
2. {
3.     Properties
4.     {
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.         SubShader
11.         {
12.             Tags { "RenderType" = "Opaque" }
13.             LOD 200
14.  
15.             CGPROGRAM
16.             // Physically based Standard lighting model, and enable shadows on all light types
17.             #pragma surface surf Standard fullforwardshadows
18.  
19.             // Use shader model 3.0 target, to get nicer looking lighting
20.             #pragma target 5.0
21.  
22. //#ifdef SHADER_API_D3D11
23.             StructuredBuffer<float> test;
24. //#endif
25.  
26.         sampler2D _MainTex;
27.  
28.         struct Input
29.         {
30.             float2 uv_MainTex;
31.         };
32.  
33.         half _Glossiness;
34.         half _Metallic;
35.         fixed4 _Color;
36.  
37.  
38.         void surf (Input IN, inout SurfaceOutputStandard o)
39.         {
40.             fixed4 c = fixed4(1, 0, 0, 1);
41.            
42. //#ifdef SHADER_API_D3D11
43.             if (test[0] == 0)
44.                 c = fixed4(0, 1, 0, 1);
45.             else if (test[0] == 1)
46.                 c = fixed4(0, 0, 1, 1);
47. //#endif
48.        
49.             o.Albedo = c.rgb;
50.             // Metallic and smoothness come from slider variables
51.             o.Metallic = _Metallic;
52.             o.Smoothness = _Glossiness;
53.             o.Alpha = c.a;
54.         }
55.         ENDCG
56.     }
57.     FallBack "Diffuse"
58. }
59.  

Gives me this error: Shader error in 'Custom/Test2': Unexpected identifier "StructuredBuffer". Expected one of: typedef const void inline uniform nointerpolation extern shared static volatile row_major column_major struct or a user-defined type at line 23

 

Yes, it works. Thank you!

Can you explain what it does? I haven't found this anywhere in docs.