// Shave and a Haircut
// (c) 2019 Epic Games
// US Patent 6720962

static GLubyte *oimage = NULL;

static unsigned long
extract_pixel( unsigned long pp )
{
// int x,y;
	unsigned long   pout;
	int             r1;
	short           rr, gg, bb, aa;

	{
		float           d;

		// float Ner,Neg,Neb,Nir,Nig,Nib;
		unsigned long   q;

		q = pp;
		rr = ( short ) ( q & ( 0xff ) );
		gg = ( short ) ( ( q & ( 0xff00 ) ) >> 8 );
		bb = ( short ) ( ( q & ( 0xff0000 ) ) >> 16 );
		aa = ( short ) ( ( q & ( 0xff000000 ) ) >> 24 );
		d = 255 - sqrt( ( rr - gg ) * ( rr - gg ) );
		aa = ( short ) d;
		r1 = ( int ) ( 255.0f - rr );
		if( gg > rr )
			gg = rr;
		rr = ( short ) ( aa * ( float ) rr / 255.0 );
		gg = ( short ) ( aa * ( float ) gg / 255.0 );
		bb = ( short ) ( aa * ( float ) bb / 255.0 );
	}
	pout = rr + ( gg << 8 ) + ( bb << 16 ) + ( aa << 24 );
	return ( pout );
}