Structured Buffer on DrawMeshInstancedIndirect with Surface Shader Oculus Quest

Unity Engine
1

Hi, I am trying for a while now to use DrawMeshInstancedIndirect to render object with textureArray on Android device. I am unable to get the textureID in structuredBuffer to work properly.

Here is a small snippet of code I use to send the buffer:

m_positionBuffer = new ComputeBuffer(instance.Count, sizeof(float) * 3);
m_textureBuffer = new ComputeBuffer(instance.Count, sizeof(float));

Vector3[] positions = new Vector3[instance.Count];
float[] textures = new float[instance.Count];

// in a for loop
positions[index] = new Vector3(pair.Value.Pos.x, pair.Value.Pos.y, pair.Value.Pos.z);
textures[index] = 1.0;


m_positionBuffer.SetData(positions);
m_textureBuffer.SetData(textures);
instanceMaterial.SetBuffer("positionBuffer", m_positionBuffer);
instanceMaterial.SetBuffer("textureBuffer", m_textureBuffer);


//later on update
Graphics.DrawMeshInstancedIndirect(instanceMesh, subMeshIndex, instanceMaterial, new Bounds(Vector3.zero, new Vector3(100.0f, 100.0f, 100.0f)), m_argsBuffer);

Here is a version of the shader that work fine when using a predefined textureId:

Shader"Custom/GPUInstanced" {
    Properties {
        _MainTexArray("Base Color Array", 2DArray) = "" {}
        _TextureIdx("Texture Idx", float) = 0.0
    }
    SubShader {
        Tags { "RenderType"="Opaque" }
LOD 200

        CGPROGRAM
        #pragma surface surf Standard addshadow fullforwardshadows
        #pragma multi_compile_instancing
        #pragma instancing_options procedural:setup


#ifdef UNITY_PROCEDURAL_INSTANCING_ENABLED
        StructuredBuffer<float3> positionBuffer;
#endif


sampler2D _MainTex;
UNITY_DECLARE_TEX2DARRAY(_MainTexArray);


UNITY_INSTANCING_BUFFER_START(Props)
    UNITY_DEFINE_INSTANCED_PROP(float, _TextureIdx)
UNITY_INSTANCING_BUFFER_END(Props)

struct Input
{
    float2 uv_MainTexArray;
};

void setup()
{
#ifdef UNITY_PROCEDURAL_INSTANCING_ENABLED
            float3 data = positionBuffer[unity_InstanceID];

            unity_ObjectToWorld._11_21_31_41 = float4(1.0f, 0, 0, 0);
            unity_ObjectToWorld._12_22_32_42 = float4(0, 1.0f, 0, 0);
            unity_ObjectToWorld._13_23_33_43 = float4(0, 0, 1.0f, 0);
            unity_ObjectToWorld._14_24_34_44 = float4(data.xyz, 1);
            unity_WorldToObject = unity_ObjectToWorld;
            unity_WorldToObject._14_24_34 *= -1;
            unity_WorldToObject._11_22_33 = 1.0f / unity_WorldToObject._11_22_33;
#endif


void surf(Input IN, inout SurfaceOutputStandard o)
{

    fixed4 c = UNITY_SAMPLE_TEX2DARRAY(
                           _MainTexArray,
                           float3(IN.uv_MainTexArray, UNITY_ACCESS_INSTANCED_PROP(Props, _TextureIdx))
                       );
  
    o.Albedo = c.rgb;
    o.Alpha = 1.0f;
}
    ENDCG
    }
    FallBack "Diffuse"
}

The moment I am trying to sample the textureId buffer then the object stop rendering:

Shader"Custom/GPUInstanced" {
    Properties {
        _MainTexArray("Base Color Array", 2DArray) = "" {}
        _TextureIdx("Texture Idx", float) = 0.0
    }
    SubShader {
        Tags { "RenderType"="Opaque" }
LOD 200

        CGPROGRAM
        #pragma surface surf Standard addshadow fullforwardshadows
        #pragma multi_compile_instancing
        #pragma instancing_options procedural:setup


#ifdef UNITY_PROCEDURAL_INSTANCING_ENABLED
        StructuredBuffer<float3> positionBuffer;
        StructuredBuffer<float> textureBuffer;
#endif


sampler2D _MainTex;
UNITY_DECLARE_TEX2DARRAY(_MainTexArray);


UNITY_INSTANCING_BUFFER_START(Props)
    UNITY_DEFINE_INSTANCED_PROP(float, _TextureIdx)
UNITY_INSTANCING_BUFFER_END(Props)

struct Input
{
    float2 uv_MainTexArray;
};

void setup()
{
#ifdef UNITY_PROCEDURAL_INSTANCING_ENABLED
            float3 data = positionBuffer[unity_InstanceID];

            unity_ObjectToWorld._11_21_31_41 = float4(1.0f, 0, 0, 0);
            unity_ObjectToWorld._12_22_32_42 = float4(0, 1.0f, 0, 0);
            unity_ObjectToWorld._13_23_33_43 = float4(0, 0, 1.0f, 0);
            unity_ObjectToWorld._14_24_34_44 = float4(data.xyz, 1);
            unity_WorldToObject = unity_ObjectToWorld;
            unity_WorldToObject._14_24_34 *= -1;
            unity_WorldToObject._11_22_33 = 1.0f / unity_WorldToObject._11_22_33;
#endif


void surf(Input IN, inout SurfaceOutputStandard o)
{
    float texture_array_id = 0.0f;
#ifdef UNITY_PROCEDURAL_INSTANCING_ENABLED
            texture_array_id = textureBuffer[unity_InstanceID];    

#endif

    fixed4 c = UNITY_SAMPLE_TEX2DARRAY(
                           _MainTexArray,
                           float3(IN.uv_MainTexArray, texture_array_id)
                       );
  
    o.Albedo = c.rgb;
    o.Alpha = 1.0f;
}
    ENDCG
    }
    FallBack "Diffuse"
}

We are using Unity 2019.4.22 Any help would be very appreciated.

2

Did you find a solution for this?