ensure that the empty polygons do not cause the node invert to crash by

erroring earlier.

Author: madhephaestus

src/main/java/eu/mihosoft/vrl/v3d/CSG.java

@@ -1419,6 +1419,10 @@ public CSG intersect(CSG csg) {
 			}
 //		triangulate();
 //		csg.triangulate();
+		if(getPolygons().size()==0 || csg.getPolygons().size()==0) {
+			System.err.println("Error! Intersection is invalid when one CSG has no polygons!");
+			return new CSG().historySync(this).historySync(csg);
+		}
 		Node a = new Node(this.clone().getPolygons());
 		Node b = new Node(csg.clone().getPolygons());
 		a.invert();

src/main/java/eu/mihosoft/vrl/v3d/CSGClient.java

@@ -131,12 +131,17 @@ private ArrayList<CSG> performOperation(List<CSG> csgList, CSGRemoteOperation op
 	 * Internal method to perform operations and handle request/response
 	 */
 	private ArrayList<CSG> performOperation(List<CSG> csgList, CSGRemoteOperation operation,List<Vector3d> points, PropertyStorage storage) throws Exception {
+		if (javafx.application.Platform.isFxApplicationThread()) {
+			RuntimeException runtimeException = new RuntimeException("Network trafic can not run on UI thread");
+			runtimeException.printStackTrace();
+			throw runtimeException;
+		}
 		ArrayList<CSG> back = null;
 		SSLSocket socket = (SSLSocket) factory.createSocket(hostname, port);
 		try {
 			ObjectOutputStream oos = new ObjectOutputStream(socket.getOutputStream());
 			ObjectInputStream ois = new ObjectInputStream(socket.getInputStream());
-			//System.out.println("Running Operation on server: " + hostname + " " + operation);
+			//
 			// Create and send request
 
 			ArrayList <CSG> toSend  =  new ArrayList<CSG>();
@@ -160,6 +165,10 @@ private ArrayList<CSG> performOperation(List<CSG> csgList, CSGRemoteOperation op
 			// Return results as ArrayList
 			back=new ArrayList<CSG>();
 			for(CSG c:response.getCsgList()) {
+				if(c.getPolygons().size()==0) {
+					System.out.println("Running Operation on server: " + hostname + " " + operation);
+					new RuntimeException("Network CSG op resulted in no polygons here ").printStackTrace();
+				}
 				CSG historySync = CSG.fromPolygons(c.getPolygons());
 				back.add( historySync);
 				for(CSG s:csgList) {
@@ -192,6 +201,8 @@ public static void close() {
 	}
 
 	public static boolean isRunning() {
+		if(javafx.application.Platform.isFxApplicationThread())
+			return false;// do not run operation on UI thread
 		if (isServerCall())
 			return false;
 		if (getClient() == null)

src/test/java/eu/mihosoft/vrl/v3d/ServerClientTest.java

@@ -58,6 +58,7 @@ public CSG prep(CSG incoming) {
 			int bpoly1 =b.getPolygons().size();
 
 			CSG u1 = a.union( b,c);
+			CSG i1 = c.intersect(b);
 			CSG d1 = a.difference(b);
 			CSG t1 = d1.clone().triangulate(true);
 			ArrayList<CSG> m1 = a.minkowskiHullShape(b);
@@ -73,7 +74,9 @@ public CSG prep(CSG incoming) {
 			CSG u =a.union( b,c);
 			if(testPoly(u1,u))
 				fail();
-			
+			CSG i0 = c.intersect(b);
+			if(testPoly(i1,i0))
+				fail();
 			CSG d = a.difference(b);
 			if(testPoly(d1,d))
 				fail("Difference Step fail , expected "+d1.getPolygons().size()+" got "+d.getPolygons().size());