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//DarkBeam's "fold"... reinterpreted... it's more than a fold, much more! Just awesome!
float DBFold(vec3 p, float fo, float g){
	if(p.z>p.y) p.yz=p.zy;//Diagonal fold
	//Tis is slightly different from the original fold in order to make it continuous in this context
	float vx=p.x-2.*fo;
	float vy=p.y-4.*fo;
 	float v=max(abs(vx+fo)-fo,vy);
	float v1=max(vx-g,p.y);
	v=min(v,v1);
	return min(v,p.x);
}
//the coordinates are pushed/pulled in parallel
vec3 DBFoldParallel(vec3 p, vec3 fo, vec3 g){
	vec3 p1=p;
	p.x=DBFold(p1,fo.x,g.x);
	p.y=DBFold(p1.yzx,fo.y,g.y);
	p.z=DBFold(p1.zxy,fo.z,g.z);
	return p;
}
//serial version
vec3 DBFoldSerial(vec3 p, vec3 fo, vec3 g){
	p.x=DBFold(p,fo.x,g.x);
	p.y=DBFold(p.yzx,fo.y,g.y);
	p.z=DBFold(p.zxy,fo.z,g.z);
	return p;
}