fixing system orders for ensuring level calculation comes last

packages/core/src/systems/item/item-system.tsx

@@ -51,7 +51,7 @@ export const ItemSystem = () => {
       }
 
       clearDirty(id as AnyNodeId)
-    })
+    }, 2)
   })
 
   return null

packages/core/src/systems/slab/slab-system.tsx

@@ -29,7 +29,7 @@ export const SlabSystem = () => {
       }
       // If mesh not found, keep it dirty for next frame
     })
-  })
+  }, 1)
 
   return null
 }

packages/core/src/systems/wall/wall-system.tsx

@@ -1,7 +1,7 @@
 import { useFrame } from '@react-three/fiber'
 import * as THREE from 'three'
-import { computeBoundsTree } from 'three-mesh-bvh'
 import { Brush, Evaluator, SUBTRACTION } from 'three-bvh-csg'
+import { computeBoundsTree } from 'three-mesh-bvh'
 import { sceneRegistry } from '../../hooks/scene-registry/scene-registry'
 import { spatialGridManager } from '../../hooks/spatial-grid/spatial-grid-manager'
 import { resolveLevelId } from '../../hooks/spatial-grid/spatial-grid-sync'
@@ -22,7 +22,7 @@ const csgEvaluator = new Evaluator()
 // WALL SYSTEM
 // ============================================================================
 
-let useFrameNb = 0;
+let useFrameNb = 0
 export const WallSystem = () => {
   const dirtyNodes = useScene((state) => state.dirtyNodes)
   const clearDirty = useScene((state) => state.clearDirty)
@@ -35,7 +35,7 @@ export const WallSystem = () => {
     // Collect dirty walls and their levels
     const dirtyWallsByLevel = new Map<string, Set<string>>()
 
-    useFrameNb += 1;    
+    useFrameNb += 1
     dirtyNodes.forEach((id) => {
       const node = nodes[id]
       if (!node || node.type !== 'wall') return
@@ -75,7 +75,7 @@ export const WallSystem = () => {
         }
       }
     }
-  })
+  }, 4)
 
   return null
 }
@@ -108,7 +108,6 @@ function updateWallGeometry(wallId: string, miterData: WallMiterData) {
   const node = nodes[wallId as WallNode['id']]
   if (!node || node.type !== 'wall') return
 
-
   const mesh = sceneRegistry.nodes.get(wallId) as THREE.Mesh
   if (!mesh) return
 

packages/core/src/systems/window/window-system.tsx

@@ -50,7 +50,7 @@ export const WindowSystem = () => {
         useScene.getState().dirtyNodes.add((node as WindowNode).parentId as AnyNodeId)
       }
     })
-  })
+  }, 3)
 
   return null
 }

packages/viewer/src/systems/level/level-system.tsx

@@ -33,7 +33,10 @@ function getLevelHeight(
     } else if (child.type === 'wall') {
       // Wall mesh is pushed up to slabElevation by WallSystem.
       // mesh.position.y + wall.height gives the actual top Y in level-local space.
-      const meshY = sceneRegistry.nodes.get(childId as any)?.position.y ?? 0
+      let meshY = sceneRegistry.nodes.get(childId as any)?.position.y ?? 0
+      if (meshY < 0) {
+        meshY = 0 // Guard against invalid negative Y which could cause incorrect height calculation (e.g. from sunken slabs)
+      }
       const top = meshY + ((child as WallNode).height ?? DEFAULT_LEVEL_HEIGHT)
       if (top > maxTop) maxTop = top
     }
@@ -78,11 +81,11 @@ export const LevelSystem = () => {
       const explodedExtra = levelMode === 'exploded' ? index * EXPLODED_GAP : 0
       const targetY = baseY + explodedExtra
 
-      obj.position.y = lerp(obj.position.y, targetY, delta * 3)
+      obj.position.y = lerp(obj.position.y, targetY, delta * 12) // Smoothly animate to new Y position
       obj.visible = levelMode !== 'solo' || level?.id === selectedLevel || !selectedLevel
 
       cumulativeY += getLevelHeight(levelId, nodes)
     }
-  })
+  }, 5) // Using a lower priority so it runs after transforms from other systems have settled
   return null
 }