void Sprite::DrawScaledAdditiveSubpixel( float x, float y, float w, float h, Surface *a_Target )
{
	const unsigned int wI = (unsigned int)w >> 1;
	const unsigned int hI = (unsigned int)h >> 1;

	const float mW = m_Width / w;
	const float mH = m_Height / h;
	Pixel *src = GetBuffer() + m_CurrentFrame * m_Width;
	// calculate screen space bounding box of the scaled image
	const int ix = ( x - 615 ) * ( x - 615 );
	const int iy = ( y - 345 ) * ( y - 345 );
	const int x1 = ( x - wI ), y1 = ( y - hI );
	const float y1f = ( y - hI );
	const int x2 = ( x + 1 + wI ), y2 = ( y + 1 + hI );
	const float x2f = ( x - wI );
	Pixel *buffer = a_Target->GetBuffer();

	const int midX = 2 + ( x2 + x1 ) >> 1;
	const int midY = 2 + ( y2 + y1 ) >> 1;
	const int pitch = a_Target->GetPitch();
	//just make everything in the centre white
	if ( ix + ( iy << 1 ) < 5500 )
	{

		for ( int j = y1; j < y2; j++ )
		{
			for ( int i = x1; i < x2; i++ )
			{
				buffer[i + j * pitch] = 0xFFFFFFFF;
			}
		}
		return;
	}

	const int m_Width_min_1 = m_Width - 1;
	const int m_Height_min_1 = m_Height - 1;
	const float xw_div_2 = ( x - w / 2.0f );
	// loop over target box; do a filtered read from source for each pixel
	for ( int j = y1; j < y2; j++ )
	{
		const float sy = max( 0.0f, ( j - ( y - h / 2.0f ) ) * mH);
		const int isy = int( sy );
		const float y_in_pixel = sy - isy;
		const int y0 = min( m_Height_min_1, isy );
		const int y1 = min( m_Height_min_1, y0 + 1 );
		const int jpitch = j * pitch;
		const int dy = midY - j;

		const float one_min_y_in_pixel = 1.0f - y_in_pixel;

		const bool y_check = ( ( dy ^ ( dy >> 31 ) ) - ( dy >> 31 ) ) < 2;

		for ( int i = x1; i < x2; i++ )
		{
			int index = i + jpitch;
			if ( buffer[index] == 0xFFFFFFFF )
			{
				continue;
			}

			const int dx = midX - i;
			if ( ( ( dx ^ ( dx >> 31 ) ) - ( dx >> 31 ) ) < 2 && y_check)
			{
				buffer[index] = 0xFFFFFFFF;
				continue;
			}

			// determine floating point (sub-pixel) source coordinates
			const float sx = ( i - xw_div_2) * mW;
			// use bilinear interpolation to read from source image
			const int isx = max(0, (int)sx);
			const float x_in_pixel = sx - isx;
			const int x0 = min( m_Width_min_1, isx );
			const int x1 = min( m_Width_min_1, isx + 1 );

			const float one_min_x_in_pixel = 1.0f - x_in_pixel;

			const float w0 = one_min_x_in_pixel * one_min_y_in_pixel;
			const float w1 = x_in_pixel * one_min_y_in_pixel;
			const float w2 = one_min_x_in_pixel * y_in_pixel;
			const float w3 = 1.0f - ( w0 + w1 + w2 );

			Pixel color = 0;

			const Pixel p0 = src[x0 + ( y0 << 9 )];
			if ( p0 > 0xFF000000 )
				color += ScaleColor( p0, ( w0 * 256.0f ) );

			const Pixel p1 = src[x1 + ( y0 << 9 )];
			if ( p1 > 0xFF000000 )
				color += ScaleColor( p1, ( w1 * 256.0f ) );

			const Pixel p2 = src[x0 + ( y1 << 9 )];
			if ( p2 > 0xFF000000 )
				color += ScaleColor( p2, ( w2 * 256.0f ) );

			const Pixel p3 = src[x1 + ( y1 << 9 )];
			if ( p3 > 0xFF000000 )
				color += ScaleColor( p3, ( w3 * 256.0f ) );

			if ( color )
			{
				buffer[index] = AddBlend( buffer[index], color );
			}
		}
	}
}