displacement GSHsinedisp( float amplitude = 0.002, wavelength = 0.0025 )
{
 //P += N * amplitude * sin( 2*3.14159*(v / wavelength) );
#if STYLE1
 P += N * (
 		amplitude * pow(noise( u / wavelength, v / wavelength),6) 
	 	+ amplitude*sin((v/(wavelength*40)) * 2 * PI)
 	);
#else
	float uc = u + 0.1*noise(u*10,v*10);
	float vc = v + 0.1*noise(u*11,v*9);
	
 P += N * (
 		amplitude*sin((uc/(wavelength*10)) * 2 * PI) 
 		+ amplitude*sin((vc/(wavelength*10)) * 2 * PI)
 	);
#endif
 N = calculatenormal(P);
}