GraphicsBuffer | Readback Data Function?

[sebastian-wolter-itk]

Currently there seems to be no readback function for reading GraphicsBuffer back.
I've tried mapping the buffer but this leads

Is there some other way to do that?

CS Code:

using Prowl.Runtime;
using Prowl.Runtime.Rendering;
using System;
using Veldrid;
public class NewScript : MonoBehaviour
{
	public AssetRef<ComputeShader> shader;
	GraphicsBuffer buffer;

    public override void Start()
	{
		Debug.Log("Start");
	}

	public override void Update()
	{
		Debug.Log("Update");

		ComputeDescriptor descriptor = new ComputeDescriptor(shader);
		descriptor.SetInt("numElements", 128);
		descriptor.SetBuffer("buffer", buffer);
		ComputeDispatcher.Dispatch(descriptor, 0, 128, 1, 1);
        Span<float> data = new float[128];
        var mappedResource = Graphics.Device.Map(buffer.Buffer, Veldrid.MapMode.ReadWrite);
        if ((data.Length * sizeof(float)) < mappedResource.SizeInBytes)
            throw new ArgumentException("Insufficient space to store the requested pixel data", nameof(data));

        unsafe
        {
            fixed (void* ptr = data)
            {
                Buffer.MemoryCopy((void*)mappedResource.Data, ptr, data.Length * sizeof(float), mappedResource.SizeInBytes);
            }
        }

        Debug.Log(data[0]);
        Debug.Log(data[1]);

        Graphics.Device.Unmap(buffer.Buffer);
    }

    public override void OnEnable()
    {
		buffer = new GraphicsBuffer(1024 * 1024, sizeof(float), true);
    }

    public override void OnDisable()
    {
		buffer.Dispose();

    }
}

Compute:

#pragma kernel main

RWStructuredBuffer<float> buffer;
int numElements;

[numthreads(1, 1, 1)]
void main( uint3 id : SV_DispatchThreadID )
{
    if(id.x >= numElements) return;
    buffer[id.x] = (float)id.x;
}