DataBuffer with better Performance

Monkey Targets Forums/XNA/DataBuffer with better Performance

Rone	(Posted 2012) [#1]

Hi,

since Databuffers are little slow on xna, I implemented an unsafe non wp7 version. Using unsafe pointer arithmetics, it is much faster...

#if WINDOWS_PHONE
		    Array.Copy(System.BitConverter.GetBytes((short)value), 0, _data, addr, 2);
#else
            unsafe
            {
                fixed (byte* ptr = &_data[addr])
                {
                    *(short*)ptr = (short)value;
                }
            }
#endif

Complete databuffer.cs

public class BBDataBuffer
{
    public byte[] _data;
    public int _length;

    public BBDataBuffer()
    {
    }

    public BBDataBuffer(int length)
    {
        _data = new byte[length];
        _length = length;
    }

    public BBDataBuffer(byte[] data)
    {
        _data = data;
        _length = data.Length;
    }

    public bool _New(int length)
    {
        if (_data != null) return false;
        _data = new byte[length];
        _length = length;
        return true;
    }

    public bool _Load(String path)
    {
        if (_data != null) return false;

        _data = MonkeyData.loadBytes(path);
        if (_data == null) return false;

        _length = _data.Length;
        return true;
    }

    public void Discard()
    {
        if (_data != null)
        {
            _data = null;
            _length = 0;
        }
    }

    public int Length()
    {
        return _length;
    }

    public void PokeByte(int addr, int value)
    {
        _data[addr] = (byte)value;
    }

    public void PokeShort(int addr, int value)
    {
#if WINDOWS_PHONE
		Array.Copy(System.BitConverter.GetBytes((short)value), 0, _data, addr, 2);
#else
        unsafe
        {
            fixed (byte* ptr = &_data[addr])
            {
                *(short*)ptr = (short)value;
            }
        }
#endif
    }

    public void PokeInt(int addr, int value)
    {
#if WINDOWS_PHONE
		Array.Copy( System.BitConverter.GetBytes( value ),0,_data,addr,4 );
#else
        unsafe
        {
            fixed (byte* ptr = &_data[addr])
            {
                *(int*)ptr = value;
            }
        }
#endif
    }

    public void PokeFloat(int addr, float value)
    {
#if WINDOWS_PHONE
        Array.Copy(System.BitConverter.GetBytes(value), 0, _data, addr, 4);
#else
        unsafe
        {
            fixed (byte* ptr = &_data[addr])
            {
                *(float*)ptr = value;
            }
        }
#endif
    }

    public int PeekByte(int addr)
    {
        return (int)(sbyte)_data[addr];
    }

    public int PeekShort(int addr)
    {
#if WINDOWS_PHONE
		return (int)System.BitConverter.ToInt16( _data,addr );
#else
        unsafe
        {
            fixed (byte* ptr = &_data[addr])
            {
                return (int)(*(short*)ptr);
            }
        }
#endif
    }

    public int PeekInt(int addr)
    {
#if WINDOWS_PHONE
		return System.BitConverter.ToInt32(_data, addr);
#else
        unsafe
        {
            fixed (byte* ptr = &_data[addr])
            {
                return *(int*)ptr;
            }
        }
#endif
    }

    public float PeekFloat(int addr)
    {
#if WINDOWS_PHONE
		return (float)System.BitConverter.ToSingle(_data, addr);
#else
        unsafe
        {
            fixed (byte* ptr = &_data[addr])
            {
                return *(float*)ptr;
            }
        }
#endif
    }
}