Finding shader nodes with no connections

Here’s a JScript snippet that finds render tree nodes that are not connected to anything in the render tree.

LogMessage( isConnected( Selection(0) ) );

function isConnected( o )
	var oDR = XSIUtils.DataRepository ;

	var strOpInfo = oDR.GetConnectionStackInfo( o )
//	LogMessage( strOpInfo );
	var oTopNode = ParseXML( strOpInfo ) ;

	var oConnections = oTopNode.childNodes ;
	if ( oConnections.length == 0 )
		return false;
	return true;

function ParseXML( strXML )
	var oXMLParser = new ActiveXObject("Microsoft.XMLDOM") 
	oXMLParser.async = false	
	oXMLParser.loadXML( strXML ) ;

	if (oXMLParser.parseError.errorCode != 0) 
		logmessage( "Invalid XML " + oXMLParser.parseError.reason , siError ) ;	
		return null ;

	// the xsi_file node
	// If this is NULL we must have failed to load the XML
	var oTopNode = oXMLParser.documentElement ;

	return oTopNode ;

Most of this JScript came from the SDK Explorer code in $XSI_HOME\Addons\sdkui\Application\Plugins\SDKExplorer.js, because I noticed that disconnected shaders would have an empty connection stack, and I didn’t want to go through all the parameters individually looking for connections.

Here’s a Python version that does a little more: it follows the output connections to check whether or not the shader is ultimately connected the material.

# Python Code
import xml.etree.ElementTree as etree

def is_connected( o ):
	if not o.IsClassOf( 52 ):
		print "Input is not a shader"
		return False
	sXML = XSIUtils.DataRepository.GetConnectionStackInfo( o )
	root = etree.fromstring( sXML )
	for connection in root:
		if connection.find('type').text == 'out':
			x = Application.Dictionary.GetObject( connection.find('object').text )
			return True if x.IsClassOf( 64 ) else is_connected( x )
	return False

print is_connected( Application.Selection(0) )

4 thoughts on “Finding shader nodes with no connections

  1. All materials for all objects in a model are selected. When I run the JScript version it doesn’t search to see if a specific shader node is (phong, Incidence etc) literally not connected to the material render tree, the script only outputs “true” or “false”.

    • Yeah, the JScript version just checks whether or not a shader has at least one input or output connection. So if a render node is not connected to anything, you’ll get True.

      • When you say, it checks whether or not a shader has at least one in-put or output connection, do you mean whether there is a shader node plugged into the material ?

        Can the script search within all selected materials to find if a shader node is literally plugged into the material tree or not ?

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s