public static vec3 Abs(this vec3 item)
{
vec3 result = new vec3(item.x, item.y, item.z);
if (result.x < 0) { result.x = -result.x; }
if (result.y < 0) { result.y = -result.y; }
if (result.z < 0) { result.z = -result.z; }
return result;
}