fix?

src/entities/shared_systems/pathfinding.rs

@@ -81,7 +81,7 @@ use crate::world::{
 use crate::{constants::*, entities::shared_components::Ambulatory};
 use bevy::math::ivec3;
 use bevy_rand::prelude::*;
-use rand::RngExt;
+use rand::{RngExt, SeedableRng};
 
 thread_local! {
     static LOCAL_PATH_TIMES: RefCell<Vec<u128>> = const { RefCell::new(Vec::new()) };
@@ -236,6 +236,7 @@ impl Plugin for PathfindingPlugin {
                     collect_pathfinding_dirty_chunks,
                     invalidate_paths_on_tile_change,
                     crate::entities::tasks::task_executor_system,
+                    update_wandering_targets,
                     prepare_paths,
                     movement,
                 )
@@ -529,14 +530,19 @@ pub fn merge_benchmark_stats(mut bench: ResMut<PathfindingBenchmark>) {
 }
 
 pub fn update_wandering_targets(
-    mut query: Query<(&mut Ambulatory, &Transform)>,
+    mut query: Query<(&mut Ambulatory, &Transform), Without<crate::entities::tasks::TaskQueue>>,
     tilemap: Res<TileMap>,
     chunk_map: Res<ChunkMap>,
-    mut rng_q: Query<&mut WyRand, With<GlobalRng>>,
+    time: Res<Time>,
 ) {
-    let Ok(mut rng) = rng_q.single_mut() else {
-        return;
-    };
+    // Use deterministic RNG - seed from SEED + time
+    use std::collections::hash_map::DefaultHasher;
+    use std::hash::{Hash, Hasher};
+    let mut hasher = DefaultHasher::new();
+    crate::constants::SEED.hash(&mut hasher);
+    time.elapsed_secs().to_bits().hash(&mut hasher);
+    let seed = hasher.finish();
+    let mut rng = WyRand::seed_from_u64(seed);
 
     for (mut ambulatory, transform) in query.iter_mut() {
         if ambulatory.target.is_none() {

src/entities/tasks/idle.rs

@@ -44,10 +44,11 @@ pub(super) fn execute_idle(
 
     // Only reset path if target changed or no path exists
     if target_changed || ambulatory.current_path.is_none() {
+        // +1.0 sub-tile offset matching original wandering system
         ambulatory.target = Some(Vec3::new(
             target.x as f32,
             target.y as f32,
-            transform.translation.z,
+            target.z as f32 + 1.0,
         ));
         ambulatory.current_path = None;
         ambulatory.path_index = 0;
@@ -56,6 +57,7 @@ pub(super) fn execute_idle(
 
 /// Pick a random standable tile within wander radius of origin.
 /// Uses reservoir sampling to avoid heap allocation.
+/// Searches for actual surface z at each XY position (like original wandering system).
 fn pick_wander_target(
     origin: &IVec3,
     radius: i32,
@@ -67,16 +69,25 @@ fn pick_wander_target(
 
     for dx in -radius..=radius {
         for dy in -radius..=radius {
-            let candidate = IVec3::new(
-                origin.x + dx * ITILE_SIZE,
-                origin.y + dy * ITILE_SIZE,
-                origin.z,
-            );
-            if tilemap.is_standable(candidate) {
-                count += 1;
-                // Reservoir sampling: 1/count chance to replace chosen
-                if rng.random_range(0..count) == 0 {
-                    chosen = Some(candidate);
+            // Search for actual surface z at this XY - same logic as original wandering
+            for z in -3i32..=4i32 {
+                let floor_pos = IVec3::new(
+                    origin.x + dx * ITILE_SIZE,
+                    origin.y + dy * ITILE_SIZE,
+                    z * ITILE_SIZE,
+                );
+                // Check if there's a floor tile at this z
+                if tilemap.floor_tiles.get(&floor_pos).is_some() {
+                    // Check if standable one tile above
+                    let above = IVec3::new(floor_pos.x, floor_pos.y, floor_pos.z + ITILE_SIZE);
+                    if tilemap.is_standable(above) {
+                        count += 1;
+                        // Reservoir sampling: 1/count chance to replace chosen
+                        if rng.random_range(0..count) == 0 {
+                            chosen = Some(above);
+                        }
+                        break; // found surface at this XY, stop z search
+                    }
                 }
             }
         }