Feedback Three things I wish Shader Graph would support

(edit: meant to post this in Shader Graph forum. Can we move it?)

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Hi,
So I've been using ShaderGraph a lot lately, and it's shaping up into a fantastic tool, but there are still things I wish it supported:

1. Make it possible to create SG shaders for Graphics.DrawProcedural()
DrawProcedural() is by very far the most powerful rendering technique for performance. More powerful than any batching or instancing, for objects that don't move. The problem is that it is a pain to use, because it requires you to write your own shaders completely with a custom vertex shader. Would it be possible to have a "ProceduralPBR" MasterNode in shadergraph? This node would basically generate a shader where users are responsible for setting buffers of positions, normals, tangents, uvs, etc... Basically, the generated shader would be exactly like standard PBR, except its vertex shader would look like this:

Spoiler: code (untested)

Code (CSharp):

1. StructuredBuffer<float3> vOSPositions;
2. StructuredBuffer<float3> vOSNormals;
3. StructuredBuffer<float3> vOSTangents;
4. StructuredBuffer<float2> vUV1;
5. StructuredBuffer<float2> vUV2;
6. StructuredBuffer<float2> vUV3;
7. StructuredBuffer<float2> vUV4;
8. StructuredBuffer<float3> vColor;
9.  
10.  
11. // Vertex input attributes
12. struct Attributes
13. {
14.     uint vertexID : SV_VertexID;
15.     UNITY_VERTEX_INPUT_INSTANCE_ID
16. };
17.  
18. // Custom vertex shader
19. PackedVaryingsType CustomVert(Attributes input)
20. {
21.     uint t_idx = input.vertexID / 3;           // Triangle index
22.     uint v_idx = input.vertexID - t_idx * 3;   // Vertex index
23.  
24.     // Imitate a common vertex input.
25.     AttributesMesh am;
26.     am.positionOS = vOSPositions[v_idx];
27. #ifdef ATTRIBUTES_NEED_NORMAL
28.     am.normalOS = vOSNormals[v_idx];
29. #endif
30. #ifdef ATTRIBUTES_NEED_TANGENT
31.     am.tangentOS = vOSTangents[v_idx];
32. #endif
33. #ifdef ATTRIBUTES_NEED_TEXCOORD0
34.     am.uv0 = vUV1[v_idx];
35. #endif
36. #ifdef ATTRIBUTES_NEED_TEXCOORD1
37.     am.uv1 = vUV2[v_idx];
38. #endif
39. #ifdef ATTRIBUTES_NEED_TEXCOORD2
40.     am.uv2 = vUV3[v_idx];
41. #endif
42. #ifdef ATTRIBUTES_NEED_TEXCOORD3
43.     am.uv3 = vUV4[v_idx];
44. #endif
45. #ifdef ATTRIBUTES_NEED_COLOR
46.     am.color = vColor[v_idx];
47. #endif
48.     UNITY_TRANSFER_INSTANCE_ID(input, am);
49.  
50.     // Throw it into the default vertex pipeline.
51.     VaryingsType varyingsType;
52.     varyingsType.vmesh = VertMesh(am);
53.     return PackVaryingsType(varyingsType);
54. }

Here is an example of it in action: this is 50 milion tris being rendered at only 6ms per frame. This would make the most powerful grass/vegetation system ever, if only SG had a "ProceduralPBR" MasterNode.
https://i.gyazo.com/994460687b3077df31f8cee3a8d2ca37.mp4

Here is a simple project demonstrating how to use it for HDRP: https://github.com/keijiro/NoiseBall4

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2. Make it possible to declare and use StructuredBuffers in SG shaders
Right now, SG doesn't allow you to make shaders that communicate efficiently with compute shaders. All we'd need to solve this is the ability to declare and use StructuredBuffers in SG

With this, we could make highly efficient dynamic ocean systems, snow tracks shaders, etc, etc....

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3. Tesselation

I assume this is coming eventually. Any new on that?

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I really don't mind if any of these things would necessitate a CustomFunction node with code in it. That would be absolutely fine, as long as we at least have an option to author shaders in shadergraph that can support all this cool stuff