Strange Thing inside Shader Textfile .hlsl

Unity Engine
,
1

I have some strange thing on my shader .hlsl textfile, that is used inside the ShaderGraph.

i’am learning always and its the first time using .hlsl Textfile inside a CustomFunction of ShaderGraph

I got this error, even when i use c0 or c1 or .m03

invalid subscript '_m03'

Thats my Code:

    static const float3x3 r[6] = {
    float3x3(1.0f, 0.0f, 0.0f,  0.0f, -1.192093E-07f, -1.0f,  0.0f, 1.0f, -1.192093E-07f), //Up
    float3x3(-10.0f, 0.0f, 0.0f,  0.0f, -1.192093E-07f, 1.0f,  0.0f, 1.0f, -1.192093E-07f), //Down
    float3x3(1.0f, 0.0f, 0.0f,  0.0f, 1.0f, 0.0f,  0.0f, 0.0f, 1.0f), //Forward
    float3x3(-1.0f, 0.0f, 0.0f,  0.0f, 1.0f, 0.0f,  0.0f, 0.0f, -1.0f), //Back
    float3x3(-1.192093E-07f, 0.0f, 1.0f,  0.0f, 1.0f, 0.0f,  -1.0f, 0.0f, -1.192093E-07f), //Left
    float3x3(-1.192093E-07f, 0.0f, -1.0f,  0.0f, 1.0f, 0.0f,  1.0f, 0.0f, -1.192093E-07f) //Right
    };

    static const float3 DirectionVector[6] = {
            float3(0, 0.5, 0), //Up
            float3(0, -0.5, 0), //Down
            float3(0, 0, -0.5), //Forward
            float3(0, 0, 0.5), //Back
            float3(-0.5, 0, 0), //Left
            float3(0.5, 0, 0) //Right
    };

void ConfigureProcedural () {
    #if defined(UNITY_PROCEDURAL_INSTANCING_ENABLED)
        int i = _Indexes[unity_InstanceID];
        int y = i / (128 * 128);
        int x = (i - y * 128 * 128) / 128;
        int z = i - y * 128 * 128 - x * 128;
        int d = (i % 6);
        float3 v = float3(x, y, z) + DirectionVector[d];
        float3x3 rot = r[d];
        float3x4 m = float3x4(rot._m00, rot._m01, rot._m02, rot._m03, rot._m10, rot._m11, rot._m12, rot._m13, rot._m20, v.x, v.y, v.z);
        float4x4 mx = float4x4(m._m00, m._m01, m._m02, m._m03, m._m10, m._m11, m._m12, m._m13, m._m20, m._m21, m._m22, m._m23, 0.0, 0.0, 0.0, 1.0);
        unity_ObjectToWorld = mx;
    #endif
}

If i change it to this:

        float3x4 m = _Matrices[unity_InstanceID];
        unity_ObjectToWorld._m00_m01_m02_m03 = m._m00_m01_m02_m03;
        unity_ObjectToWorld._m10_m11_m12_m13 = m._m10_m11_m12_m13;
        unity_ObjectToWorld._m20_m21_m22_m23 = m._m20_m21_m22_m23;
        unity_ObjectToWorld._m30_m31_m32_m33 = float4(0.0, 0.0, 0.0, 1.0);

it works fine…

_Matrices is a StructuredBuffer with float3x4
_Indexes is a Buffer with ints inside

If i got this working, i sending much less data to the gpu using the buffers.

Why I’am need such performance, i will build my base-structure so good as possible, because iam adding more features to it which costs performance over all. Example are more realistic shaders with moveing grass water and so on.

Some other thing that is not important for the moment:

In future i want to change from

    Buffer<int> _Indexes;

to

    Buffer<short> _Indexes; //stride of 2
    Buffer<byte> _Indexes; //stride of 1

this makes possible to sending less data, because i’am only sending values from 0 to 255, not more. I read that Buffer is faster as StructuredBuffer for this case, is this right? and whats the difference to a RWBuffer or RWStructuredBuffer?

2

#Push / Edit:

I’am understanding a bit about Matrix4x4 (float4x4 is used in my shader)
But i can’t find any documentation about unity_ObjectToWorld and why i the first 3 collumns of the float4x4 is used by rotation?

My rotations are only directionally like Forward, Up, Backward, Left, Right… so i only need -1 or 1 in rotation. i tried assign other values than a float4x4 to the unity_ObjectToWorld but it needs a 4x4 thing.

Is there a simpler or faster way to set the objects position?
It will be nice if i find some documentation about float4x4 and unity_ObjectToWorld.

The Scale of the Objects/Meshs are the same, rotation is only directionally and position is in int-space like Vector3(0, 1, 3) and so on.

Some other Questions i got.
Is there a LOD for Quads? or is a quad the minimum?

3

You’re using rot._m03. The rot is a float3x3, it doesn’t have a fourth column.

4

I got it to half working, the errors are out, but the position of the quads are now only 1 line?

#if defined(UNITY_PROCEDURAL_INSTANCING_ENABLED)
    Buffer<int> _Indexes;
#endif

    static const float3 rot1[6] = {
        float3(1.0, 0.0, 0.0), //Up
        float3(-1.0, 0.0, 0.0), //Down
        float3(1.0, 0.0, 0.0), //Forward
        float3(-1.0, 0.0, 0.0), //Back
        float3(-1.0, 0.0, 1.0), //Left
        float3(-1.0, 0.0, -1.0) //Right
    };

    static const float3 rot2[6] = {
    float3(0.0, -1.0, -1.0), //Up
    float3(0.0, -1.0, 1.0), //Down
    float3(0.0, 1.0, 0.0), //Forward
    float3(0.0, 1.0, 0.0), //Back
    float3(0.0, 1.0, 0.0), //Left
    float3(0.0, 1.0, 0.0) //Right
    };

    static const float3 rot3[6] = {
    float3(0.0, 1.0, -1.0), //Up
    float3(0.0, 1.0, -1.0), //Down
    float3(0.0, 0.0, 1.0), //Forward
    float3(0.0, 0.0, -1.0), //Back
    float3(-1.0, 0.0, -1.0), //Left
    float3(1.0, 0.0, -1.0) //Right
    };

    static const float3 DirectionVector[6] = {
            float3(0, 0.5, 0), //Up
            float3(0, -0.5, 0), //Down
            float3(0, 0, -0.5), //Forward
            float3(0, 0, 0.5), //Back
            float3(-0.5, 0, 0), //Left
            float3(0.5, 0, 0) //Right
    };

void ConfigureProcedural () {
    #if defined(UNITY_PROCEDURAL_INSTANCING_ENABLED)
        int i = _Indexes[unity_InstanceID];
        int y = i / (128 * 128);
        int x = (i - y * 128 * 128) / 128;
        int z = i - y * 128 * 128 - x * 128;
        int d = (i % 6);
        float3 v = float3(x, y, z) + DirectionVector[d];
        float3x4 m = float3x4(rot1[d], rot2[d], rot3[d], v);
      
        unity_ObjectToWorld._m00_m01_m02_m03 = m._m00_m01_m02_m03;
        unity_ObjectToWorld._m10_m11_m12_m13 = m._m10_m11_m12_m13;
        unity_ObjectToWorld._m20_m21_m22_m23 = m._m20_m21_m22_m23;
        unity_ObjectToWorld._m30_m31_m32_m33 = float4(0.0, 0.0, 0.0, 1.0);
    #endif
}

void ShaderGraphFunction_half (half3 In, out half3 Out) {
    Out = In;
}

I splitt the float3x3 r to 3 float3’s because every time i use .c0 or one of the m_00 things i got an error.
Now i got no errors, but the result is only a line of quads.

The functions like int x =… are same as i did before in the jobs.

don’t worry about the “128” it’s the current RenderDistance or Amount of Voxel-Positions, i put it in by hand for testing.

5

Update [SOLVED]: I got it working right, i make a misstake at Matrix.

        unity_ObjectToWorld._m00_m01_m02 = rot1[d] / 1.0; //Size x
        unity_ObjectToWorld._m10_m11_m12 = rot2[d] / 1.0; //Size y
        unity_ObjectToWorld._m20_m21_m22 = rot3[d] / 1.0; //Rotation / Size z

        unity_ObjectToWorld._m03_m13_m23 = v; //Position
        unity_ObjectToWorld._m33 = 1.0; //Immer 1.0 for Projection

That’s the correct Matrix now.