New pattern

[boytchev]

Add the following texture pattern (or it derivative):

function pattern( x, y, z, color, options, u, v, px, py )
{
	var k=0;
	
	var k1=0.5+0.5*noise(10*x,10*y,10*z);
	var k2=0.5+0.5*noise(20*x,20*y,20*z);
	
	k = 1-20*(k1-k2)**2;
	if( k<0.999 ) k==0;
	
//	if(xx==100)console.log(py,px,xx)
	
//	if( MathUtils.seededRandom(Math.round(px**2+py))>0.98 ) k=1;
	color.set(k,k,k);
	...