Fix to_dot handling of groups using downcasts.

src/nodes/group.rs

@@ -351,9 +351,7 @@ impl NodeGroup {
                 self.incoming_edges(idx)
             };
             let node = g_clone.node_weight(idx).unwrap();
-            let outgoing_edges: HashMap<String, Option<LightData>> = HashMap::new();
-            
-            //node.borrow().analyze(incoming_edges, analyzer_type)?;
+            let outgoing_edges: HashMap<String, Option<LightData>> = node.borrow_mut().analyze(incoming_edges, analyzer_type)?;
             let mut group_sinks = g_clone.externals(Direction::Outgoing);
             // Check if node is group sink node
             if group_sinks.any(|gs| gs == idx) {
@@ -618,6 +616,9 @@ impl Optical for NodeGroup {
     fn set_inverted(&mut self, inverted: bool) {
         self.is_inverted = inverted;
     }
+    fn as_group(&self) -> Result<&NodeGroup> {
+        Ok(&self)
+    }
 }
 
 impl Dottable for NodeGroup {

src/optic_scenery.rs

-use std::cell::{Ref, RefCell};
+use std::cell::RefCell;
 use std::collections::HashMap;
 use std::rc::Rc;
 
 use crate::analyzer::AnalyzerType;
-use crate::dottable::Dottable;
 use crate::error::OpossumError;
 use crate::light::Light;
 use crate::lightdata::LightData;
@@ -43,7 +42,7 @@ impl OpticScenery {
     /// This command just adds an optical element (a struct implementing the [`Optical`](crate::optic_node::Optical) trait such as [`crate::nodes::Dummy`] ) to the graph. It does not connect
     /// it to existing nodes in the graph. The given optical element is consumed (owned) by the [`OpticScenery`]. Internally the corresponding [`OpticNode`] is
     /// automatically generated. It serves as a short-cut to the `add_node` function.
-    pub fn add_element<T: OpticComponent + 'static>(&mut self, name: &str, t: T) -> NodeIndex {
+    pub fn add_element<T: OpticComponent + 'static>(&mut self, _name: &str, t: T) -> NodeIndex {
         self.g.add_node(Rc::new(RefCell::new(t)))
     }
     /// Connect (already existing) nodes denoted by the respective `NodeIndex`.
@@ -182,24 +181,6 @@ impl OpticScenery {
         dot_string.push_str("\tedge [fontname=\"Helvetica,Arial,sans-serif\"]\n\n");
         dot_string
     }
-    // fn cast_node_to_group<'a>(&self, ref_node: &'a Ref<'_, dyn Optical>) -> Result<&'a NodeGroup> {
-    //     let node_boxed = &*ref_node;
-    //     let downcasted_node = node_boxed.    .downcast_ref::<NodeGroup>();
-
-    //     match downcasted_node {
-    //         Some(i) => Ok(i),
-    //         _ => Err(OpossumError::OpticScenery(
-    //             "can not cast OpticNode to specific type of NodeGroup!".into(),
-    //         )),
-    //     }
-    // }
-    fn check_if_group<T: Optical>(&self, node_ref: T) -> bool {
-        if node_ref.node_type() == "group" {
-            true
-        } else {
-            false
-        }
-    }
     fn create_node_edge_str(
         &self,
         end_node: NodeIndex,
@@ -213,12 +194,12 @@ impl OpticScenery {
             format!("{}_i{}", &parent_identifier, end_node.index())
         };
 
-        // if self.check_if_group(node) {
-        //     let group_node: &NodeGroup = self.cast_node_to_group(&node)?;
-        //     Ok(group_node.get_mapped_port_str(light_port, parent_identifier)?)
-        // } else {
+        if node.node_type()=="group" {
+             let group_node: &NodeGroup = node.as_group()?;
+             Ok(group_node.get_mapped_port_str(light_port, parent_identifier)?)
+        } else {
         Ok(format!("i{}:{}", end_node.index(), light_port))
-        // }
+        }
     }
     /// Analyze this [`OpticScenery`] based on a given [`AnalyzerType`].
     pub fn analyze(&mut self, analyzer_type: &AnalyzerType) -> Result<()> {

src/optical.rs

@@ -2,6 +2,7 @@ use crate::analyzer::AnalyzerType;
 use crate::dottable::Dottable;
 use crate::error::OpossumError;
 use crate::lightdata::LightData;
+use crate::nodes::NodeGroup;
 use crate::optic_ports::OpticPorts;
 use core::fmt::Debug;
 use std::any::Any;
@@ -73,6 +74,10 @@ pub trait Optical: Dottable {
     fn inverted(&self) -> bool {
         false
     }
+    fn as_group(&self) -> Result<&NodeGroup> {
+        Err(OpossumError::Other("cannot cast to group".into()))
+    }
+
 }
 
 impl Debug for dyn Optical {