feat: reconcile tree span with land at each generation

src/bin/ponderosa-cpu.rs

@@ -134,6 +134,13 @@ fn main() -> io::Result<()> {
                 continue;
             }
 
+            // Reconcile the tree's span with the current state of the land
+            for x in 0..8 {
+                for y in 0..8 {
+                    tree.span[x][y] = land.get(&(x.try_into().unwrap(), y.try_into().unwrap()));
+                }
+            }
+
             let instructions = &rules[tree.rule_id as usize];
 
             // tree.resume_from will be 0, unless it's awoken after having to
@@ -183,6 +190,18 @@ fn main() -> io::Result<()> {
 
                 instruction_pointer += 1;
             }
+
+
+            // Update the land with the new state of every tree.
+            for tree_index in 0..scheduled_trees.len() {
+                let tree_id = &scheduled_trees[tree_index];
+                let tree = trees.get(tree_id).unwrap();
+                for x in 0..8 {
+                    for y in 0..8 {
+                        land.sow(&(x, y), tree.span[x as usize][y as usize]);
+                    }
+                }
+            }
         }
 
         while let Some(tree_index) = trees_to_compost_by_index.pop_first() {

src/state.rs

@@ -91,6 +91,10 @@ impl Land {
     pub fn reap(&mut self, position: &(u16, u16)) -> u16 {
         self.map.insert((position.0 % self.width, position.1 % self.height), 0).unwrap_or(0)
     }
+
+    pub fn get(&self, position: &(u16, u16)) -> u16 {
+        *self.map.get(&(position.0 % self.width, position.1 % self.height)).unwrap_or(&0)
+    }
 }
 
 pub type Rule = VecDeque<u16>;