I was wondering if anyone could shed some light on why the default pbr diffuse node multiplies the diffuse result by 2? below is the code from ‘pbrdiffuse’.


vector $tnN = $isconnected_nN ? $nN : normalize(N);

if ($drough > 0)
{
$f = 2.0*diffuse($tnN, $drough, “label”, $label);
}
else
{
$f = 2.0*diffuse($tnN, “label”, $label);
}


thanks

The diffuse albedo in Houdini has historically been 0.5, and so when they rewrote it, they maintained backward compatibility and adjusted after the fact. Not pretty, but that's the reason, if I recall correctly.

Look at the bottom of this page:
http://www.sidefx.com/docs/houdini13.0/vex/functions/diffuse [sidefx.com]

Ok thanks Jason