3DPruningImprovements PR Fixes

src/scenic/core/pruning.py

@@ -431,7 +431,7 @@ def bufferHelper(viewRegion):
             if (
                 base is not ego.visibleRegion
                 and not needsSampling(ego.visibleRegion)
-                and not checkCyclical(scenario, base, ego.visibleRegion)
+                and not checkCyclical(base, ego.visibleRegion)
             ):
                 if verbosity >= 1:
                     print(
@@ -446,7 +446,7 @@ def bufferHelper(viewRegion):
             if (
                 base is not obj._observingEntity.visibleRegion
                 and not needsSampling(obj._observingEntity.visibleRegion)
-                and not checkCyclical(scenario, base, obj._observingEntity.visibleRegion)
+                and not checkCyclical(base, obj._observingEntity.visibleRegion)
             ):
                 if verbosity >= 1:
                     print(
@@ -596,15 +596,11 @@ def percentagePruned(base, newBase):
     return None
 
 
-def checkCyclical(scenario, A, B):
+def checkCyclical(A, B):
     """Check for a potential circular dependency
 
     Returns True if the scenario would have a circular dependency
     if A depended on B.
-
-    This function runs DFS on the scenario, with the dependency edges
-    reversed for convenience (this should not affect whether or not a
-    cycle exists).
     """
     state = collections.defaultdict(lambda: 0)
 
@@ -621,10 +617,10 @@ def dfs(target):
         # Recurse on children
         deps = conditionedDeps(target)
 
-        if target is A:
-            deps.append(B)
-
         for child in deps:
+            if child is A:
+                return True
+
             if dfs(child):
                 return True
 
@@ -633,7 +629,7 @@ def dfs(target):
 
         return False
 
-    return dfs(scenario)
+    return dfs(B)
 
 
 def conditionedDeps(samp):

src/scenic/core/regions.py

@@ -2088,10 +2088,6 @@ def __init__(self, voxelGrid, orientation=None, name=None, lazy=False):
         self.voxel_points = self.voxelGrid.points
         self.scale = self.voxelGrid.scale
 
-        # Initialize KD-Tree for containment checking if not lazy
-        if not lazy:
-            self.kdTree
-
     @cached_property
     def kdTree(self):
         return scipy.spatial.KDTree(self.voxel_points)

tests/syntax/test_pruning.py

@@ -4,6 +4,7 @@
 import pytest
 
 from scenic.core.errors import InconsistentScenarioError
+from scenic.core.pruning import checkCyclical
 from scenic.core.vectors import Vector
 from tests.utils import compileScenic, sampleEgo, sampleParamP
 
@@ -209,12 +210,37 @@ def test_visibility_pruning():
 
 
 def test_visibility_pruning_cyclical():
-    """A case where a cyclical dependency could be introduced if pruning is not done carefully."""
+    """A case where a cyclical dependency could be introduced if pruning is not done carefully.
+
+    NOTE: We don't currently prune this case so this test is a sentinel for future behavior.
+    """
     scenario = compileScenic(
         """
         workspace = Workspace(PolygonalRegion([0@0, 100@0, 100@100, 0@100]))
         foo = new Object with requireVisible True, in workspace
         ego = new Object visible from foo, in workspace
     """
     )
+
     sampleEgo(scenario, maxIterations=100)
+
+
+def test_checkCyclical():
+    scenario = compileScenic(
+        """
+        workspace = Workspace(PolygonalRegion([0@0, 100@0, 100@100, 0@100]))
+        foo = new Object in workspace
+        ego = new Object in workspace
+    """
+    )
+    assert not checkCyclical(scenario.objects[1].position, scenario.objects[0].position)
+
+    scenario = compileScenic(
+        """
+        workspace = Workspace(PolygonalRegion([0@0, 100@0, 100@100, 0@100]))
+        foo = new Object with requireVisible True, in workspace
+        ego = new Object visible from foo
+    """
+    )
+
+    assert checkCyclical(scenario.objects[1].position, scenario.objects[0].visibleRegion)