// slang bug, using 2024.13
// slangc -profile ms_6_5 -entry main test_ms.slang -o test_ms.spv

// The shader constant is totally random UNLESS I add some EXTRA code that uses it
// See line 48 - if I add the multiply it works perfectrly

struct UniformBufferObject {
    float time;
};

[[vk::binding(0, 0)]] ConstantBuffer<UniformBufferObject> ubo;

struct MeshOutput {
    float4 Position : SV_Position;
    float3 Color : COLOR;
};

[shader("mesh")]
[numthreads(1, 1, 1)]
[outputtopology("triangle")]
void main(uint threadID : SV_GroupIndex, out indices uint3 Triangles[1], out vertices MeshOutput Vertices[3])
{
    SetMeshOutputCounts(3, 1);

    // Define three vertices of a triangle
    float2 positions[3] = {
        float2( 0.0,  0.5), // Top
        float2( 0.5, -0.5), // Right
        float2(-0.5, -0.5)  // Left
    };

    float3 colors[3] = {
        float3(1, 0, 0), // Red
        float3(0, 1, 0), // Green
        float3(0, 0, 1)  // Blue
    };

    // Assign vertex data
    for (uint i = 0; i < 3; i++)
    {
        float t = ubo.time;
        float2 p = positions[i];

        float x = p.x * cos(t) - p.y * sin(t);
        float y = p.x * sin(t) + p.y * cos(t);

        Vertices[i].Position = float4(x, y, 0.0, 1.0);
        Vertices[i].Color = colors[i]; // * fmod(t, 1.0); // Comment the fmod in, and it works!
    }

    // Define triangle indices
    Triangles[0] = uint3(0, 1, 2);
}