Merge pull request #12866 from Mugen87/dev6

ColladaLoader: Fix #12855

examples/js/loaders/ColladaLoader.js

@@ -1624,7 +1624,15 @@ THREE.ColladaLoader.prototype = {
 
 		function getCamera( id ) {
 
-			return getBuild( library.cameras[ id ], buildCamera );
+			var data = library.cameras[ id ];
+
+			if ( data !== undefined ) {
+
+				return getBuild( data, buildCamera );
+
+			}
+
+			return null;
 
 		}
 
@@ -1749,7 +1757,15 @@ THREE.ColladaLoader.prototype = {
 
 		function getLight( id ) {
 
-			return getBuild( library.lights[ id ], buildLight );
+			var data = library.lights[ id ];
+
+			if ( data !== undefined ) {
+
+				return getBuild( data, buildLight );
+
+			}
+
+			return null;
 
 		}
 
@@ -3037,7 +3053,13 @@ THREE.ColladaLoader.prototype = {
 
 			for ( var i = 0, l = instanceCameras.length; i < l; i ++ ) {
 
-				objects.push( getCamera( instanceCameras[ i ] ).clone() );
+				var instanceCamera = getCamera( instanceCameras[ i ] );
+
+				if ( instanceCamera !== null ) {
+
+					objects.push( instanceCamera.clone() );
+
+				}
 
 			}
 
@@ -3076,7 +3098,13 @@ THREE.ColladaLoader.prototype = {
 
 			for ( var i = 0, l = instanceLights.length; i < l; i ++ ) {
 
-				objects.push( getLight( instanceLights[ i ] ).clone() );
+				var instanceLight = getLight( instanceLights[ i ] );
+
+				if ( instanceLight !== null ) {
+
+					objects.push( instanceLight.clone() );
+
+				}
 
 			}