improve parent selection

benches/future_children.rs

@@ -8,9 +8,9 @@ use std::time::Duration;
 fn extend_layers_test(depth: usize) {
     let config = FutureMoveConfig {
         max_depth: depth,
-        start_pruning_at_minus: 4,
+        min_arena_depth_sub: 4,
         top_k_children: 2,
-        up_to_mod: 4,
+        up_to_minus: 4,
         max_arena_size: 10_000_000,
     };
     let mut fut = FutureMoves::new(Piece::Black, config);

src/complexagent.rs

@@ -14,10 +14,10 @@ impl ComplexAgent {
     pub const fn new(color: Piece) -> Self {
         const CONFIG: FutureMoveConfig = FutureMoveConfig {
             max_depth: 10,
-            start_pruning_at_minus: 4,
+            min_arena_depth_sub: 3,
             top_k_children: 2,
-            up_to_mod: 4,
+            up_to_minus: 4,
-            max_arena_size: 100_000_000,
+            max_arena_size: 10_000_000,
         };
         Self {
             color,

src/logic/future_moves.rs

@@ -26,16 +26,17 @@ pub struct FutureMoveConfig {
     /// Max depth of that we should try and traverse
     pub max_depth: usize,
 
-    /// start pruning at X depth before self.max_depth is reached
+    /// subtract this value from FutureMove.max_depth
-    /// used for pruning during tree generation before the tree is fully grown
+    /// and that would be the min depth an arena should fill for
-    pub start_pruning_at_minus: usize,
+    /// pruning to happen
+    pub min_arena_depth_sub: usize,
 
     /// when pruning, keep the top_k # of children
     pub top_k_children: usize,
 
     // the lower the value, the more conservative the pruning is, what level to stop pruning at?
     // a lower value allows more possible paths
-    pub up_to_mod: usize,
+    pub up_to_minus: usize,
 
     /// Max size of the arena, will not generate more if
     /// the arena is of that size or bigger
@@ -71,7 +72,7 @@ impl FutureMoves {
                 // we want to select all nodes that don't have children, or are lazy (need to maybe be regenerated)
                 .filter(|&idx| {
                     let got = &self.arena[idx];
-                    got.is_trimmed || got.children.is_empty()
+                    !got.is_trimmed && got.winner == Winner::None && !got.tried_children
                 })
                 .filter(|&idx| self.is_connected_to_root(idx))
                 .collect::<Vec<usize>>()
@@ -84,7 +85,8 @@ impl FutureMoves {
                     .unwrap(),
                 )
                 .for_each(|node_idx| {
-                    self.generate_children(node_idx);
+                    self.generate_children(node_idx).last();
+                    self.arena[node_idx].tried_children = true;
                 });
 
             self.prune_bad_children();
@@ -109,14 +111,11 @@ impl FutureMoves {
     }
 
     /// Creates children for a parent (`parent`), returns an iterator it's children's indexes
-    fn generate_children(&mut self, parent_idx: usize) -> Option<impl Iterator<Item = usize>> {
+    /// Completely unchecked, the caller should be the one who tests to make sure child generation
+    /// hasn't already been tried on a parent
+    fn generate_children(&mut self, parent_idx: usize) -> impl Iterator<Item = usize> {
         let parent = &self.arena[parent_idx];
 
-        // early-exit if a winner for the parent already exists
-        if parent.winner != Winner::None {
-            return None;
-        }
-
         let new_color = !parent.color;
 
         // use [`Board::all_positions`] here instead of [`Board::possible_moves`]
@@ -140,7 +139,7 @@ impl FutureMoves {
             self.set_parent_child(parent_idx, child_idx);
         }
 
-        Some(new_indices)
+        new_indices
     }
 
     /// Given an index from `self.arena`, what depth is it at? 0-indexed
@@ -346,7 +345,7 @@ impl FutureMoves {
         if self
             .config
             .max_depth
-            .saturating_sub(self.config.start_pruning_at_minus)
+            .saturating_sub(self.config.min_arena_depth_sub)
             > self.current_depth
         {
             return;
@@ -354,7 +353,7 @@ impl FutureMoves {
 
         for (depth, indexes) in by_depth {
             // TODO! maybe update by_depth every iteration or something?
-            if depth > self.current_depth.saturating_sub(self.config.up_to_mod) {
+            if depth > self.current_depth.saturating_sub(self.config.up_to_minus) {
                 return;
             }
 
@@ -454,9 +453,17 @@ impl FutureMoves {
 mod tests {
     use super::*;
 
+    const FUTURE_MOVES_CONFIG: FutureMoveConfig = FutureMoveConfig {
+        max_depth: 1,
+        min_arena_depth_sub: 2,
+        top_k_children: 2,
+        up_to_minus: 0,
+        max_arena_size: 100,
+    };
+
     #[test]
     fn prune_tree_test() {
-        let mut futm = FutureMoves::new(Piece::Black, Default::default());
+        let mut futm = FutureMoves::new(Piece::Black, FUTURE_MOVES_CONFIG);
 
         futm.arena.push(Move {
             i: 0,
@@ -469,6 +476,7 @@ mod tests {
             self_value: 0,
             color: Piece::Black,
             is_trimmed: false,
+            tried_children: false,
         });
 
         futm.update_root_idx_raw(0);
@@ -508,7 +516,7 @@ mod tests {
 
     #[test]
     fn expand_layer_test() {
-        let mut futm = FutureMoves::new(Piece::Black, Default::default());
+        let mut futm = FutureMoves::new(Piece::Black, FUTURE_MOVES_CONFIG);
         futm.config.max_depth = 1;
 
         futm.arena.push(Move::new(
@@ -541,7 +549,7 @@ mod tests {
 
     #[test]
     fn depth_of_test() {
-        let mut futm = FutureMoves::new(Piece::Black, Default::default());
+        let mut futm = FutureMoves::new(Piece::Black, FUTURE_MOVES_CONFIG);
 
         futm.arena.push(Move {
             i: 0,
@@ -554,6 +562,7 @@ mod tests {
             self_value: 0,
             color: Piece::Black,
             is_trimmed: false,
+            tried_children: false,
         });
 
         futm.update_root_idx_raw(0);
@@ -587,7 +596,7 @@ mod tests {
 
     #[test]
     fn by_depth_test() {
-        let mut futm = FutureMoves::new(Piece::Black, Default::default());
+        let mut futm = FutureMoves::new(Piece::Black, FUTURE_MOVES_CONFIG);
 
         futm.arena.push(Move {
             i: 0,
@@ -600,6 +609,7 @@ mod tests {
             self_value: 0,
             color: Piece::Black,
             is_trimmed: false,
+            tried_children: false,
         });
 
         futm.update_root_idx_raw(0);

src/logic/move.rs

@@ -22,6 +22,9 @@ pub struct Move {
     /// Indices of this Move's Children
     pub children: Vec<usize>,
 
+    /// Has this [`Move`] already attempted to create children?
+    pub tried_children: bool,
+
     /// Value of this move (including children)
     pub value: Option<i128>,
 
@@ -52,6 +55,7 @@ impl Move {
             color,
             is_trimmed: false,
             self_value: 0,
+            tried_children: false,
         };
         m.self_value = m.compute_self_value(agent_color);
         m