Copy array to struct array as fast as possible in C#

Question

I am working with Unity 4.5, grabbing images as bytes arrays (each byte represent a channel, taking 4 bytes per pixel (rgba) and displaying them on a texture converting the

Answer 1

This code requires unsafe switch but should be fast. I think you should benchmark these answers...

var bytes = new byte[] { 1, 2, 3, 4 };

var colors = MemCopyUtils.ByteArrayToColor32Array(bytes);

---

public class MemCopyUtils
{
    unsafe delegate void MemCpyDelegate(byte* dst, byte* src, int len);
    static MemCpyDelegate MemCpy;

    static MemCopyUtils()
    {
        InitMemCpy();
    }

    static void InitMemCpy()
    {
        var mi = typeof(Buffer).GetMethod(
            name: "Memcpy",
            bindingAttr: BindingFlags.NonPublic | BindingFlags.Static,
            binder:  null,
            types: new Type[] { typeof(byte*), typeof(byte*), typeof(int) },
            modifiers: null);
        MemCpy = (MemCpyDelegate)Delegate.CreateDelegate(typeof(MemCpyDelegate), mi);
    }

    public unsafe static Color32[] ByteArrayToColor32Array(byte[] bytes)
    {
        Color32[] colors = new Color32[bytes.Length / sizeof(Color32)];

        fixed (void* tempC = &colors[0])
        fixed (byte* pBytes = bytes)
        {
            byte* pColors = (byte*)tempC;
            MemCpy(pColors, pBytes, bytes.Length);
        }
        return colors;
    }
}