Improve ident calculation to help with tree drawing

otg/core/src/types.rs

@@ -307,11 +307,13 @@ impl<T> Tree<T> {
     //
     // indent represents the indentation that should be applied to all children in this tree. It
     // amounts to the position of the parent node.
-    pub fn position(&self, indent: usize, idx: usize) -> (usize, usize) {
-        println!("[{}]", idx);
+    //
+    // When drawing nodes, I don't know how to persist the level of indent.
+    pub fn position(&self, idx: usize) -> (usize, usize) {
         let node = &self.nodes[idx];
         match node.parent {
             Some(parent_idx) => {
+                let (_parent_row, parent_column) = self.position(parent_idx);
                 let parent = &self.nodes[parent_idx];
                 let sibling_width = parent
                     .children
@@ -319,7 +321,7 @@ impl<T> Tree<T> {
                     .take_while(|n| **n != node.id)
                     .fold(0, |acc, n| acc + self.width(*n));
                 println!("[{}] sibling width {}", idx, sibling_width);
-                (node.depth, indent + sibling_width)
+                (node.depth, parent_column + sibling_width)
             }
 
             // Root nodes won't have a parent, so just put them in the first column
@@ -538,13 +540,13 @@ mod test {
 
         let tree = Tree::from(&game_tree);
 
-        assert_eq!(tree.position(0, 2), (2, 0));
-        assert_eq!(tree.position(0, 1), (1, 0));
-        assert_eq!(tree.position(0, 0), (0, 0));
-        assert_eq!(tree.position(0, 4), (3, 1));
-        assert_eq!(tree.position(0, 5), (3, 2));
-        assert_eq!(tree.position(0, 6), (1, 3));
-        assert_eq!(tree.position(0, 7), (1, 4));
+        assert_eq!(tree.position(2), (2, 0));
+        assert_eq!(tree.position(1), (1, 0));
+        assert_eq!(tree.position(0), (0, 0));
+        assert_eq!(tree.position(4), (3, 1));
+        assert_eq!(tree.position(5), (3, 2));
+        assert_eq!(tree.position(6), (1, 3));
+        assert_eq!(tree.position(7), (1, 4));
     }
 
     #[test]

otg/gtk/src/components/review_tree.rs

@@ -77,7 +77,7 @@ impl ReviewTree {
                     // the parent? do I need to just make it more intrinsically a part of the position
                     // code?
                     ctx.set_source_rgb(0.7, 0.7, 0.7);
-                    let (row, column) = tree.position(0, node.id);
+                    let (row, column) = tree.position(node.id);
                     println!("[{}] {} x {}", node.id, row, column);
                     let y = (row as f64) * 20. + 10.;
                     let x = (column as f64) * 20. + 10.;