True placement reach bound

- Add PlacementReach: centered half-extent reach from loaded object keys, scale and shrink chains, enumerated rotation kernels, translate, warp and vacuum
- Size the object pass write radius and read radius from PlacementReach instead of full object width
- Size floating reach from scaled and shrunk object spans
- Count cave profile vacuum modes and upper-dimension effective rotation in the object reach
- Keep the transition-band footprint check on its existing footprint
- Add runner-backed and pack-wide reach tests

core/src/test/java/art/arcane/iris/generation/mantle/MantleFloatingObjectComponentBoundaryRadiusTest.java

@@ -31,11 +31,6 @@ import art.arcane.iris.testsupport.PlatformBinding;
 import art.arcane.volmlib.util.collection.KList;
 import org.junit.Rule;
 import org.junit.Test;
-import org.junit.rules.TemporaryFolder;
-
-import java.io.DataOutputStream;
-import java.io.File;
-import java.io.FileOutputStream;
 
 import static org.junit.Assert.assertEquals;
 import static org.mockito.Mockito.mock;
@@ -45,22 +40,12 @@ public class MantleFloatingObjectComponentBoundaryRadiusTest {
     @Rule
     public final PlatformBinding platform = PlatformBinding.mockPlatform();
 
-    @Rule
-    public TemporaryFolder temporaryFolder = new TemporaryFolder();
-
     @Test
     @SuppressWarnings("unchecked")
-    public void transformedFloatingPlacementExpandsOwnerRadius() throws Exception {
-        File objectFile = temporaryFolder.newFile("floating.iob");
-        try (DataOutputStream output = new DataOutputStream(new FileOutputStream(objectFile))) {
-            output.writeInt(1);
-            output.writeInt(1);
-            output.writeInt(1);
-        }
-
+    public void transformedFloatingPlacementExpandsOwnerRadius() {
         IrisObjectPlacement placement = new IrisObjectPlacement()
                 .setPlace(new KList<>("test/floating"))
-                .setTranslate(new IrisObjectTranslate().setX(32));
+                .setTranslate(new IrisObjectTranslate().setX(-32));
         IrisFloatingChildBiomes floatingChild = new IrisFloatingChildBiomes()
                 .setFloatingObjects(new KList<>(placement));
         IrisBiome biome = new IrisBiome().setFloatingChildBiomes(new KList<>(floatingChild));
@@ -69,7 +54,7 @@ public class MantleFloatingObjectComponentBoundaryRadiusTest {
         when(dimension.getReachableBiomes(org.mockito.ArgumentMatchers.any())).thenReturn(new KList<>(biome));
 
         ResourceLoader<IrisObject> objectLoader = mock(ResourceLoader.class);
-        when(objectLoader.findFile("test/floating")).thenReturn(objectFile);
+        when(objectLoader.load("test/floating")).thenReturn(new IrisObject(1, 1, 1));
         IrisData data = mock(IrisData.class);
         when(data.getObjectLoader()).thenReturn(objectLoader);
 
@@ -79,8 +64,8 @@ public class MantleFloatingObjectComponentBoundaryRadiusTest {
         when(engineMantle.getEngine()).thenReturn(engine);
         when(engineMantle.getData()).thenReturn(data);
 
-        assertEquals(33, new MantleFloatingObjectComponent(engineMantle).getRadius());
+        assertEquals(32, new MantleFloatingObjectComponent(engineMantle).getRadius());
         when(dimension.getAllObjectScaleFactor()).thenReturn(2D);
-        assertEquals(34, new MantleFloatingObjectComponent(engineMantle).getRadius());
+        assertEquals(33, new MantleFloatingObjectComponent(engineMantle).getRadius());
     }
 }

core/src/test/java/art/arcane/iris/generation/mantle/MantleObjectComponentBoundaryRadiusTest.java

@@ -24,7 +24,6 @@ import art.arcane.iris.spi.IrisPlatforms;
 import art.arcane.volmlib.nativelib.terrain.NativeBlockState;
 import art.arcane.iris.spi.PlatformRegistries;
 import art.arcane.iris.testsupport.PlatformLeakGuard;
-import art.arcane.iris.generation.geometry.IrisBlockVector;
 import art.arcane.iris.generation.context.ChunkContext;
 import art.arcane.volmlib.util.collection.KList;
 import art.arcane.volmlib.util.mantle.runtime.Mantle;
@@ -33,13 +32,8 @@ import art.arcane.volmlib.util.matter.Matter;
 import org.junit.After;
 import org.junit.Before;
 import org.junit.ClassRule;
-import org.junit.Rule;
 import org.junit.Test;
-import org.junit.rules.TemporaryFolder;
 
-import java.io.DataOutputStream;
-import java.io.File;
-import java.io.FileOutputStream;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.concurrent.atomic.AtomicInteger;
@@ -60,9 +54,6 @@ public class MantleObjectComponentBoundaryRadiusTest {
     @ClassRule
     public static final PlatformLeakGuard PLATFORM_GUARD = PlatformLeakGuard.clean();
 
-    @Rule
-    public TemporaryFolder temporaryFolder = new TemporaryFolder();
-
     @Before
     public void bindPlatform() {
         IrisPlatforms.unbind();
@@ -92,7 +83,7 @@ public class MantleObjectComponentBoundaryRadiusTest {
                 .setRotation(IrisObjectRotation.of(90, 0, 0))
                 .setTranslate(new IrisObjectTranslate().setX(3).setY(4));
 
-        assertEquals(53, MantleObjectComponent.calculatePlacementReach(new IrisBlockVector(5, 48, 7), placement, 1D));
+        assertEquals(27, PlacementReach.of(new IrisObject(5, 48, 7), placement, 1D).horizontal());
     }
 
     @Test
@@ -103,7 +94,7 @@ public class MantleObjectComponentBoundaryRadiusTest {
                 .setMode(ObjectPlaceMode.VACUUM)
                 .setVacuumSettings(new IrisVacuumSettings().setRadius(12));
 
-        assertEquals(39, MantleObjectComponent.calculatePlacementReach(new IrisBlockVector(5, 4, 3), placement, placement.getMaximumScale(null)));
+        assertEquals(22, PlacementReach.of(new IrisObject(5, 4, 3), placement, placement.getMaximumScale(null)).horizontal());
     }
 
     @Test
@@ -126,15 +117,12 @@ public class MantleObjectComponentBoundaryRadiusTest {
     public void inheritedRadiusMatchesScaledFrameAndExplicitScaleOverridesIt() {
         IrisDimension dimension = new IrisDimension().setAllObjectScaleFactor(2D);
         IrisObjectPlacement inherited = new IrisObjectPlacement();
-        IrisBlockVector size = new IrisBlockVector(8, 8, 8);
-        assertEquals(16, MantleObjectComponent.calculatePlacementReach(size, inherited,
-                inherited.getMaximumScale(dimension)));
+        IrisObject object = new IrisObject(8, 8, 8);
+        assertEquals(8, PlacementReach.of(object, inherited, inherited.getMaximumScale(dimension)).horizontal());
         dimension.setAllObjectScaleFactor(0.5D);
-        assertEquals(4, MantleObjectComponent.calculatePlacementReach(size, inherited,
-                inherited.getMaximumScale(dimension)));
+        assertEquals(2, PlacementReach.of(object, inherited, inherited.getMaximumScale(dimension)).horizontal());
         inherited.setScale(new IrisObjectScale().setSize(1D));
-        assertEquals(8, MantleObjectComponent.calculatePlacementReach(size, inherited,
-                inherited.getMaximumScale(dimension)));
+        assertEquals(4, PlacementReach.of(object, inherited, inherited.getMaximumScale(dimension)).horizontal());
     }
 
     @Test
@@ -183,10 +171,11 @@ public class MantleObjectComponentBoundaryRadiusTest {
 
     @Test
     public void collisionInputRadiusCoversBothSourceTraversalLegs() {
-        assertEquals(82, MantleObjectComponent.calculateInputRadius(33, false));
-        assertEquals(130, MantleObjectComponent.calculateInputRadius(33, true));
+        assertEquals(84, MantleObjectComponent.calculateInputRadius(33, 35, false));
+        assertEquals(132, MantleObjectComponent.calculateInputRadius(33, 35, true));
+        assertEquals(82, MantleObjectComponent.calculateInputRadius(33, 0, false));
         assertEquals(Integer.MAX_VALUE,
-                MantleObjectComponent.calculateInputRadius(Integer.MAX_VALUE, true));
+                MantleObjectComponent.calculateInputRadius(Integer.MAX_VALUE, Integer.MAX_VALUE, true));
     }
 
     @Test
@@ -199,7 +188,7 @@ public class MantleObjectComponentBoundaryRadiusTest {
         for (int radius = 0; radius < 300; radius++) {
             for (boolean collisions : new boolean[]{false, true}) {
                 assertTrue(MantleObjectComponent.calculateEagerInputRadius(radius, collisions)
-                        <= MantleObjectComponent.calculateInputRadius(radius, collisions));
+                        <= MantleObjectComponent.calculateInputRadius(radius, radius, collisions));
             }
         }
         assertEquals(Integer.MAX_VALUE,
@@ -231,27 +220,25 @@ public class MantleObjectComponentBoundaryRadiusTest {
         when(engineMantle.getEngine()).thenReturn(engine);
         when(engineMantle.getData()).thenReturn(data);
 
-        assertEquals(53, new MantleObjectComponent(engineMantle).getRadius());
+        assertEquals(27, new MantleObjectComponent(engineMantle).getRadius());
     }
 
     @Test
+    @SuppressWarnings("unchecked")
     public void upperDimensionObjectsDriveRadiusAndCollisionMode() {
         IrisObjectPlacement placement = new IrisObjectPlacement()
+                .setPlace(new KList<>("upper/tree"))
                 .setRotation(IrisObjectRotation.of(90, 0, 0))
                 .setTranslate(new IrisObjectTranslate().setX(3).setY(4));
         placement.getForbiddenCollisions().add("upper/blocker");
         IrisData baseData = mock(IrisData.class);
         IrisData upperData = mock(IrisData.class);
-        IrisProceduralPlacement proceduralPlacement = mock(IrisProceduralPlacement.class);
-        when(proceduralPlacement.getVariantObjects(upperData))
-                .thenReturn(new KList<>(new IrisObject(5, 48, 7)));
-        when(proceduralPlacement.asPlacement()).thenReturn(placement);
-        IrisProceduralObjects proceduralObjects = mock(IrisProceduralObjects.class);
-        when(proceduralObjects.isEmpty()).thenReturn(false);
-        when(proceduralObjects.getAllPlacements()).thenReturn(new KList<>(proceduralPlacement));
+        ResourceLoader<IrisObject> upperObjects = mock(ResourceLoader.class);
+        when(upperObjects.load("upper/tree")).thenReturn(new IrisObject(5, 48, 7));
+        when(upperData.getObjectLoader()).thenReturn(upperObjects);
         IrisRegion upperRegion = mock(IrisRegion.class);
-        when(upperRegion.getObjects()).thenReturn(new KList<>());
-        when(upperRegion.getProceduralObjects()).thenReturn(proceduralObjects);
+        when(upperRegion.getObjects()).thenReturn(new KList<>(placement));
+        when(upperRegion.getSurfaceObjects()).thenReturn(new KList<>(placement));
         IrisDimension baseDimension = mock(IrisDimension.class);
         when(baseDimension.getAllObjectScaleFactor()).thenReturn(1D);
         when(baseDimension.isUpperDimensionObjects()).thenReturn(true);
@@ -273,20 +260,13 @@ public class MantleObjectComponentBoundaryRadiusTest {
 
         MantleObjectComponent component = new MantleObjectComponent(engineMantle);
 
-        assertEquals(53, component.getRadius());
-        assertEquals(182, component.getInputRadius());
+        assertEquals(5, component.getRadius());
+        assertEquals(41, component.getInputRadius());
     }
 
     @Test
     @SuppressWarnings("unchecked")
-    public void translatedTreeCachesDistantSourcesAndSchedulesOnlyItsDestination() throws Exception {
-        File objectFile = temporaryFolder.newFile("tree.iob");
-        try (DataOutputStream output = new DataOutputStream(new FileOutputStream(objectFile))) {
-            output.writeInt(1);
-            output.writeInt(1);
-            output.writeInt(1);
-        }
-
+    public void translatedTreeCachesDistantSourcesAndSchedulesOnlyItsDestination() {
         IrisObjectPlacement placement = new IrisObjectPlacement()
                 .setPlace(new KList<>("test/tree"))
                 .setTranslate(new IrisObjectTranslate().setX(32));
@@ -298,7 +278,7 @@ public class MantleObjectComponentBoundaryRadiusTest {
         when(dimension.getReachableBiomes(any())).thenReturn(new KList<>(biome));
 
         ResourceLoader<IrisObject> objectLoader = mock(ResourceLoader.class);
-        when(objectLoader.findFile("test/tree")).thenReturn(objectFile);
+        when(objectLoader.load("test/tree")).thenReturn(new IrisObject(1, 1, 1));
         IrisData data = mock(IrisData.class);
         when(data.getObjectLoader()).thenReturn(objectLoader);
 
@@ -310,9 +290,9 @@ public class MantleObjectComponentBoundaryRadiusTest {
         when(engineMantle.getData()).thenReturn(data);
 
         MantleObjectComponent component = spy(new MantleObjectComponent(engineMantle));
-        assertEquals(33, component.getRadius());
+        assertEquals(32, component.getRadius());
         assertEquals(0, component.getOutputRadius());
-        assertEquals(82, component.getInputRadius());
+        assertEquals(68, component.getInputRadius());
 
         Mantle<Matter> mantle = mock(Mantle.class);
         MantleChunk<Matter> chunk = mock(MantleChunk.class);
@@ -341,9 +321,9 @@ public class MantleObjectComponentBoundaryRadiusTest {
 
         component.generateLayer(directWriter, 0, 0, mock(ChunkContext.class));
 
-        assertEquals(49, directOrigins.get());
+        assertEquals(25, directOrigins.get());
         component.generateLayer(directWriter, 0, 0, mock(ChunkContext.class));
-        assertEquals(49, directOrigins.get());
+        assertEquals(25, directOrigins.get());
 
         List<String> generatedChunks = new ArrayList<>();
         doAnswer(invocation -> {
@@ -370,14 +350,14 @@ public class MantleObjectComponentBoundaryRadiusTest {
                 component.getRadius(),
                 (chunkX, chunkZ) -> replayedSources.add(chunkX + "," + chunkZ)
         );
-        assertEquals(49, replayedSources.size());
-        assertEquals("-3,-3", replayedSources.getFirst());
-        assertEquals("-3,-2", replayedSources.get(1));
-        assertEquals("3,3", replayedSources.getLast());
+        assertEquals(25, replayedSources.size());
+        assertEquals("-2,-2", replayedSources.getFirst());
+        assertEquals("-2,-1", replayedSources.get(1));
+        assertEquals("2,2", replayedSources.getLast());
 
         placement.getForbiddenCollisions().add("test/tree");
         component.hotload();
-        assertEquals(130, component.getInputRadius());
+        assertEquals(100, component.getInputRadius());
     }
 
     private static final class TestMatterGenerator implements MatterGenerator {

core/src/test/java/art/arcane/iris/generation/mantle/PlacementReachPackTest.java

@@ -0,0 +1,517 @@
+package art.arcane.iris.generation.mantle;
+
+import art.arcane.iris.generation.biome.IrisBiome;
+import art.arcane.iris.generation.biome.IrisFloatingChildBiomes;
+import art.arcane.iris.generation.decoration.IrisProceduralObjects;
+import art.arcane.iris.generation.decoration.IrisProceduralPlacement;
+import art.arcane.iris.generation.geometry.IrisBlockVector;
+import art.arcane.iris.generation.runtime.Engine;
+import art.arcane.iris.generation.runtime.MeteredCache;
+import art.arcane.iris.generation.runtime.PreservationRegistry;
+import art.arcane.iris.generation.terrain.IrisDimension;
+import art.arcane.iris.generation.terrain.IrisRegion;
+import art.arcane.iris.pack.loading.IrisData;
+import art.arcane.iris.spi.IrisPlatform;
+import art.arcane.iris.spi.IrisPlatforms;
+import art.arcane.iris.spi.IrisServices;
+import art.arcane.iris.spi.PlatformRegistries;
+import art.arcane.iris.structure.object.FloatingObjectFootprint;
+import art.arcane.iris.structure.object.IrisAxisRotationClamp;
+import art.arcane.iris.structure.object.IrisObject;
+import art.arcane.iris.structure.object.IrisObjectPlacement;
+import art.arcane.iris.structure.object.IrisObjectRotation;
+import art.arcane.iris.structure.object.IrisObjectScale;
+import art.arcane.iris.structure.object.IrisObjectTranslate;
+import art.arcane.iris.structure.object.IrisObjectPlacementScaleInterpolator;
+import art.arcane.iris.testsupport.PlatformLeakGuard;
+import art.arcane.volmlib.nativelib.terrain.NativeBlockState;
+import art.arcane.volmlib.util.collection.KList;
+import art.arcane.volmlib.util.math.Vector3i;
+import it.unimi.dsi.fastutil.ints.IntArrayList;
+import it.unimi.dsi.fastutil.longs.LongOpenHashSet;
+import org.junit.After;
+import org.junit.Assume;
+import org.junit.Before;
+import org.junit.ClassRule;
+import org.junit.Test;
+import org.mockito.Answers;
+
+import java.io.BufferedInputStream;
+import java.io.DataInputStream;
+import java.io.File;
+import java.io.IOException;
+import java.nio.charset.StandardCharsets;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.ArrayList;
+import java.util.LinkedHashSet;
+import java.util.List;
+import java.util.Locale;
+import java.util.Map;
+import java.util.Set;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.ExecutorService;
+import java.util.function.Consumer;
+import java.util.stream.Stream;
+
+import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.ArgumentMatchers.anyBoolean;
+import static org.mockito.ArgumentMatchers.anyString;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
+import static org.mockito.Mockito.withSettings;
+
+public class PlacementReachPackTest {
+    @ClassRule
+    public static final PlatformLeakGuard PLATFORM_GUARD = PlatformLeakGuard.clean();
+
+    private static final int SPIN_PERIOD = 360;
+    private static final int MAXIMUM_CHECKED_KERNELS = 4096;
+    private static final String V2_HEADER = "Iris V2 IOB;";
+
+    private File pack;
+    private IrisData data;
+    private IrisDimension dimension;
+
+    @Before
+    public void loadPack() throws IOException {
+        String configured = System.getenv("IRIS_TEST_PACK");
+        Assume.assumeTrue(configured != null && !configured.isBlank());
+        pack = new File(configured).getAbsoluteFile();
+        Assume.assumeTrue(new File(pack, "objects").isDirectory());
+        File[] dimensions = new File(pack, "dimensions").listFiles((folder, name) -> name.endsWith(".json"));
+        Assume.assumeTrue(dimensions != null && dimensions.length > 0);
+        bindPlatform(Files.createTempDirectory("iris-placement-reach").toFile());
+        data = IrisData.get(pack);
+        String dimensionKey = System.getenv().getOrDefault("IRIS_TEST_PACK_DIMENSION",
+                dimensions[0].getName().substring(0, dimensions[0].getName().length() - 5));
+        dimension = data.getDimensionLoader().load(dimensionKey);
+        assertTrue("dimension " + dimensionKey + " must load", dimension != null);
+    }
+
+    @After
+    public void unbindPlatform() {
+        IrisServices.remove(PreservationRegistry.class);
+        IrisPlatforms.unbind();
+    }
+
+    @Test
+    public void everyObjectFileStaysInsideItsReachUnderRightAngleRotations() throws IOException {
+        List<IrisObjectPlacement> placements = List.of(
+                new IrisObjectPlacement(),
+                new IrisObjectPlacement().setRotation(rotation(new IrisAxisRotationClamp(true, false, 0D, 0D, 90D),
+                        new IrisAxisRotationClamp(true, false, 0D, 0D, 90D), new IrisAxisRotationClamp())),
+                new IrisObjectPlacement().setRotation(rotation(new IrisAxisRotationClamp(),
+                        new IrisAxisRotationClamp(true, false, 0D, 0D, 90D), new IrisAxisRotationClamp(true, false, 0D, 0D, 90D))),
+                new IrisObjectPlacement().setRotation(IrisObjectRotation.of(0D, 0D, 0D)),
+                new IrisObjectPlacement().setRotation(rotation(new IrisAxisRotationClamp(),
+                        new IrisAxisRotationClamp(true, false, 0D, 0D, 45D), new IrisAxisRotationClamp()))
+                        .setTranslate(new IrisObjectTranslate().setX(7).setZ(-3)));
+        List<Path> files;
+        try (Stream<Path> walk = Files.walk(new File(pack, "objects").toPath())) {
+            files = walk.filter(path -> path.toString().endsWith(".iob")).sorted().toList();
+        }
+        assertTrue(!files.isEmpty());
+        Statistics statistics = new Statistics();
+        NativeBlockState marker = mock(NativeBlockState.class, withSettings().stubOnly());
+        for (Path file : files) {
+            IrisObject object = readPositions(file, marker);
+            for (IrisObjectPlacement placement : placements) {
+                verifyCentered(file.toString(), object, placement, PlacementReach.of(object, placement, 1D), statistics);
+            }
+        }
+        System.out.println("PLACEMENT_REACH_FILES objects=" + files.size() + " " + statistics);
+    }
+
+    @Test
+    public void everyPackPlacementStaysInsideItsReach() {
+        Statistics statistics = new Statistics();
+        Set<IrisObjectPlacement> placements = new LinkedHashSet<>();
+        for (IrisRegion region : dimension.getAllRegions(() -> data)) {
+            placements.addAll(region.getObjects());
+        }
+        for (IrisBiome biome : dimension.getReachableBiomes(() -> data)) {
+            placements.addAll(biome.getObjects());
+        }
+        for (IrisObjectPlacement placement : placements) {
+            for (String key : placement.getPlace()) {
+                IrisObject object = data.getObjectLoader().load(key);
+                if (object == null) {
+                    continue;
+                }
+                PlacementReach reach = PlacementReach.of(object, placement, placement.getMaximumScale(dimension));
+                forEachVariant(object, placement, 1D, variant -> verifyCentered(key, variant, placement, reach, statistics));
+            }
+        }
+        for (IrisProceduralPlacement procedural : proceduralPlacements()) {
+            KList<IrisObject> variants = procedural.getVariantObjects(data);
+            if (variants == null) {
+                continue;
+            }
+            IrisObjectPlacement placement = procedural.asPlacement();
+            for (IrisObject variant : variants) {
+                PlacementReach reach = PlacementReach.of(variant, placement, placement.getMaximumScale(dimension));
+                forEachVariant(variant, placement, 1D,
+                        scaled -> verifyCentered(variant.getLoadKey(), scaled, placement, reach, statistics));
+            }
+        }
+        assertTrue(statistics.checked > 0);
+        System.out.println("PLACEMENT_REACH_PLACEMENTS placements=" + placements.size() + " " + statistics);
+    }
+
+    @Test
+    public void floatingPlacementsStayInsideTheirReach() {
+        Statistics statistics = new Statistics();
+        for (IrisBiome biome : dimension.getReachableBiomes(() -> data)) {
+            KList<IrisFloatingChildBiomes> entries = biome.getFloatingChildBiomes();
+            if (entries == null) {
+                continue;
+            }
+            for (IrisFloatingChildBiomes entry : entries) {
+                double shrink = entry.hasObjectShrink() ? entry.getShrinkScale().getMaxScale() : 1D;
+                IrisBiome target = entry.getRealBiome(biome, data);
+                for (IrisObjectPlacement placement : listOrEmpty(entry.getFloatingObjects())) {
+                    verifyFloating(placement, shrink, false, statistics);
+                }
+                List<IrisObjectPlacement> anchored = new ArrayList<>();
+                anchored.addAll(listOrEmpty(entry.getExtraObjects()));
+                anchored.addAll(listOrEmpty(entry.getTopObjectOverrides()));
+                anchored.addAll(listOrEmpty(entry.getBottomObjectOverrides()));
+                if (target != null) {
+                    anchored.addAll(listOrEmpty(entry.resolveTopObjects(target)));
+                    anchored.addAll(listOrEmpty(entry.resolveBottomObjects(target)));
+                }
+                for (IrisObjectPlacement placement : anchored) {
+                    verifyFloating(placement, shrink, true, statistics);
+                }
+            }
+        }
+        System.out.println("PLACEMENT_REACH_FLOATING " + statistics);
+    }
+
+    @Test
+    public void reportsTheMantleWindow() {
+        Engine engine = mock(Engine.class);
+        when(engine.getDimension()).thenReturn(dimension);
+        EngineMantle engineMantle = mock(EngineMantle.class);
+        when(engineMantle.getEngine()).thenReturn(engine);
+        when(engineMantle.getData()).thenReturn(data);
+        MantleObjectComponent objects = new MantleObjectComponent(engineMantle);
+        MantleFloatingObjectComponent floating = new MantleFloatingObjectComponent(engineMantle);
+        int objectRadius = objects.getRadius();
+        int objectInput = objects.getInputRadius();
+        int objectEager = objects.getEagerInputRadius(objectInput);
+        int floatingRadius = floating.getRadius();
+        int floatingPassRadius = chunkRadius(floatingRadius);
+        int objectPassRadius = chunkRadius(floatingRadius);
+        int terrainRadius = chunkRadius(floatingRadius + objectEager + 1);
+        int writerRadius = 2 * chunkRadius(floatingRadius + objectInput + 1);
+        System.out.println("PLACEMENT_REACH_WINDOW objectReach=" + objectRadius
+                + " objectInput=" + objectInput
+                + " objectEager=" + objectEager
+                + " sourceChunkRadius=" + MantleObjectComponent.sourceChunkRadius(objectRadius)
+                + " floatingReach=" + floatingRadius
+                + " floatingPassRadius=" + floatingPassRadius
+                + " objectPassRadius=" + objectPassRadius
+                + " terrainRadius=" + terrainRadius
+                + " terrainWindow=" + ((2 * terrainRadius) + 1) + "x" + ((2 * terrainRadius) + 1)
+                + " writerRadius=" + writerRadius);
+        assertTrue(objectRadius > 0);
+    }
+
+    private void verifyFloating(IrisObjectPlacement placement, double shrink, boolean anchored, Statistics statistics) {
+        if (placement == null || placement.getPlace() == null) {
+            return;
+        }
+        for (String key : placement.getPlace()) {
+            IrisObject object = data.getObjectLoader().load(key);
+            if (object == null) {
+                continue;
+            }
+            PlacementReach.Extent extent = PlacementReach.Extent.of(object)
+                    .scaled(placement.getMaximumScale(dimension)).scaled(shrink);
+            if (!anchored) {
+                PlacementReach reach = PlacementReach.of(extent, placement);
+                forEachVariant(object, placement, shrink, variant -> verifyCentered(key, variant, placement, reach, statistics));
+                continue;
+            }
+            PlacementReach reach = PlacementReach.anchored(extent, placement);
+            forEachVariant(object, placement, shrink, variant -> verifyAnchored(key, variant, reach, statistics));
+        }
+    }
+
+    private void verifyAnchored(String key, IrisObject variant, PlacementReach reach, Statistics statistics) {
+        FloatingObjectFootprint footprint = FloatingObjectFootprint.compute(variant);
+        List<IrisBlockVector> positions = positions(variant);
+        List<IrisObjectRotation> rotations = List.of(IrisObjectRotation.of(0D, 0D, 0D),
+                IrisObjectRotation.xFlip180WithY(0D), IrisObjectRotation.xFlip180WithY(90D),
+                IrisObjectRotation.xFlip180WithY(180D), IrisObjectRotation.xFlip180WithY(270D));
+        for (IrisObjectRotation rotation : rotations) {
+            IrisBlockVector anchor = rotation.rotate(new IrisBlockVector(footprint.getTallestKx(), 0, footprint.getTallestKz()), 0, 0, 0);
+            int actual = 0;
+            for (IrisBlockVector position : positions) {
+                IrisBlockVector rotated = rotation.rotate(position, 0, 0, 0);
+                actual = Math.max(actual, Math.abs((int) Math.round(rotated.getX()) - anchor.getBlockX()));
+                actual = Math.max(actual, Math.abs((int) Math.round(rotated.getZ()) - anchor.getBlockZ()));
+            }
+            record(key, actual, reach.horizontal(), statistics);
+        }
+    }
+
+    private void verifyCentered(String key, IrisObject object, IrisObjectPlacement placement, PlacementReach reach,
+                                Statistics statistics) {
+        IrisObjectRotation rotation = placement.getRotation();
+        IrisObjectTranslate translate = placement.getTranslate();
+        boolean translating = translate != null && translate.canTranslate();
+        int[] spinsX = spins(rotation, 0);
+        int[] spinsY = spins(rotation, 1);
+        int[] spinsZ = spins(rotation, 2);
+        List<IrisBlockVector> positions = positions(object);
+        long kernels = (long) spinsX.length * spinsY.length * spinsZ.length;
+        if (kernels > MAXIMUM_CHECKED_KERNELS) {
+            fail("rotation for " + key + " has " + kernels + " kernels");
+        }
+        for (int spinX : spinsX) {
+            for (int spinY : spinsY) {
+                for (int spinZ : spinsZ) {
+                    IrisBlockVector offset = translating
+                            ? rotation.rotate(new IrisBlockVector(translate.getX(), translate.getY(), translate.getZ()), spinX, spinY, spinZ)
+                            : null;
+                    int actual = 0;
+                    for (IrisBlockVector position : positions) {
+                        IrisBlockVector moved = rotation.rotate(position, spinX, spinY, spinZ).clone();
+                        if (offset != null) {
+                            moved.add(offset);
+                        }
+                        actual = Math.max(actual, Math.abs((int) Math.round(moved.getX())));
+                        actual = Math.max(actual, Math.abs((int) Math.round(moved.getZ())));
+                    }
+                    record(key, actual, reach.horizontal(), statistics);
+                }
+            }
+        }
+    }
+
+    private static IrisObject readPositions(Path file, NativeBlockState marker) throws IOException {
+        try (DataInputStream input = new DataInputStream(new BufferedInputStream(Files.newInputStream(file)))) {
+            IrisObject object = new IrisObject(input.readInt(), input.readInt(), input.readInt());
+            input.mark(Short.BYTES + V2_HEADER.length());
+            int headerLength = input.readUnsignedShort();
+            boolean v2 = headerLength == V2_HEADER.length()
+                    && V2_HEADER.equals(new String(input.readNBytes(headerLength), StandardCharsets.US_ASCII));
+            if (!v2) {
+                input.reset();
+            }
+            int paletteSize = v2 ? input.readShort() : 0;
+            for (int index = 0; index < paletteSize; index++) {
+                input.readUTF();
+            }
+            int blocks = input.readInt();
+            for (int index = 0; index < blocks; index++) {
+                IrisBlockVector position = new IrisBlockVector(input.readShort(), input.readShort(), input.readShort());
+                if (v2) {
+                    input.readShort();
+                } else {
+                    input.readUTF();
+                }
+                object.getBlocks().put(position, marker);
+            }
+            return object;
+        }
+    }
+
+    private static void record(String key, int actual, int reach, Statistics statistics) {
+        statistics.checked++;
+        statistics.maximumActual = Math.max(statistics.maximumActual, actual);
+        statistics.maximumReach = Math.max(statistics.maximumReach, reach);
+        statistics.slack += reach - actual;
+        if (actual > reach) {
+            fail(key + " places a block " + actual + " blocks from its origin, beyond its reach " + reach);
+        }
+    }
+
+    private static List<IrisBlockVector> positions(IrisObject object) {
+        List<IrisBlockVector> positions = new ArrayList<>(object.getBlocks().size() + 8);
+        object.getBlocks().forEach((position, state) -> positions.add(position));
+        Vector3i center = object.getCenter();
+        int[] xs = {-center.getBlockX(), object.getW() - center.getBlockX() - 1};
+        int[] ys = {-center.getBlockY(), object.getH() - center.getBlockY() - 1};
+        int[] zs = {-center.getBlockZ(), object.getD() - center.getBlockZ() - 1};
+        for (int x : xs) {
+            for (int y : ys) {
+                for (int z : zs) {
+                    positions.add(new IrisBlockVector(x, y, z));
+                }
+            }
+        }
+        return positions;
+    }
+
+    private void forEachVariant(IrisObject object, IrisObjectPlacement placement, double shrink, Consumer<IrisObject> consumer) {
+        IrisObjectScale scale = placement.getScale();
+        IrisObjectPlacementScaleInterpolator interpolation = scale == null || scale.getInterpolation() == null
+                ? IrisObjectPlacementScaleInterpolator.NONE : scale.getInterpolation();
+        for (double factor : scales(placement)) {
+            IrisObject variant = factor == 1D && (scale == null || !scale.shouldScale())
+                    ? object
+                    : scale == null ? IrisObjectScale.getFixed(object, factor) : object.scaled(factor, interpolation);
+            consumer.accept(shrink < 1D ? variant.scaled(shrink, IrisObjectPlacementScaleInterpolator.NONE) : variant);
+        }
+    }
+
+    private double[] scales(IrisObjectPlacement placement) {
+        IrisObjectScale scale = placement.getScale();
+        if (scale == null) {
+            return new double[]{dimension.getAllObjectScaleFactor()};
+        }
+        if (!scale.shouldScale()) {
+            return new double[]{1D};
+        }
+        if (scale.getSize() != 1D) {
+            return new double[]{scale.getSize()};
+        }
+        if (scale.getMinimumScale() == scale.getMaximumScale()) {
+            return new double[]{scale.getMinimumScale()};
+        }
+        int count = Math.max(1, Math.min(scale.getVariations(), 32));
+        double[] scales = new double[count];
+        for (int index = 0; index < count; index++) {
+            scales[index] = scale.getMinimumScale() + (((scale.getMaximumScale() - scale.getMinimumScale()) / count) * index);
+        }
+        return scales;
+    }
+
+    private List<IrisProceduralPlacement> proceduralPlacements() {
+        List<IrisProceduralPlacement> placements = new ArrayList<>();
+        for (IrisRegion region : dimension.getAllRegions(() -> data)) {
+            addProcedural(placements, region.getProceduralObjects());
+        }
+        for (IrisBiome biome : dimension.getReachableBiomes(() -> data)) {
+            addProcedural(placements, biome.getProceduralObjects());
+        }
+        return placements;
+    }
+
+    private static void addProcedural(List<IrisProceduralPlacement> placements, IrisProceduralObjects procedural) {
+        if (procedural != null && !procedural.isEmpty()) {
+            placements.addAll(procedural.getAllPlacements());
+        }
+    }
+
+    private static int[] spins(IrisObjectRotation rotation, int axis) {
+        if (rotation == null || !rotation.canRotate()) {
+            return new int[]{0};
+        }
+        boolean rotates = switch (axis) {
+            case 0 -> rotation.canRotateX();
+            case 1 -> rotation.canRotateY();
+            default -> rotation.canRotateZ();
+        };
+        if (!rotates) {
+            return new int[]{0};
+        }
+        LongOpenHashSet angles = new LongOpenHashSet();
+        IntArrayList spins = new IntArrayList();
+        for (int spin = -SPIN_PERIOD + 1; spin < SPIN_PERIOD; spin++) {
+            double angle = switch (axis) {
+                case 0 -> rotation.getXRotation(spin);
+                case 1 -> rotation.getYRotation(spin);
+                default -> rotation.getZRotation(spin);
+            };
+            if (angles.add(Double.doubleToLongBits(angle))) {
+                spins.add(spin);
+            }
+        }
+        return spins.toIntArray();
+    }
+
+    private static <T> List<T> listOrEmpty(KList<T> list) {
+        return list == null ? List.of() : list;
+    }
+
+    private static IrisObjectRotation rotation(IrisAxisRotationClamp x, IrisAxisRotationClamp y, IrisAxisRotationClamp z) {
+        IrisObjectRotation rotation = new IrisObjectRotation();
+        rotation.setEnabled(true);
+        rotation.setXAxis(x);
+        rotation.setYAxis(y);
+        rotation.setZAxis(z);
+        return rotation;
+    }
+
+    private static int chunkRadius(int blockRadius) {
+        return blockRadius > 0 ? Math.ceilDiv(blockRadius, 16) : 0;
+    }
+
+    private static void bindPlatform(File dataFolder) {
+        IrisPlatforms.unbind();
+        Map<String, NativeBlockState> states = new ConcurrentHashMap<>();
+        PlatformRegistries registries = mock(PlatformRegistries.class, withSettings().stubOnly());
+        when(registries.block(anyString())).thenAnswer(invocation -> state(states, invocation.getArgument(0)));
+        when(registries.blockOrNull(anyString())).thenAnswer(invocation -> state(states, invocation.getArgument(0)));
+        when(registries.blockOrNull(anyString(), anyBoolean())).thenAnswer(invocation -> state(states, invocation.getArgument(0)));
+        when(registries.air()).thenAnswer(invocation -> state(states, "minecraft:air"));
+        IrisPlatform platform = mock(IrisPlatform.class, Answers.CALLS_REAL_METHODS);
+        when(platform.dataFolder()).thenReturn(dataFolder);
+        when(platform.dataFile(any(String[].class))).thenAnswer(invocation -> {
+            Object[] path = invocation.getRawArguments();
+            return new File(dataFolder, String.join(File.separator, (String[]) path[0]));
+        });
+        when(platform.registries()).thenReturn(registries);
+        IrisPlatforms.bind(platform);
+        IrisServices.register(PreservationRegistry.class, new IgnoredPreservation());
+    }
+
+    private static NativeBlockState state(Map<String, NativeBlockState> states, String key) {
+        return states.computeIfAbsent(key, ignored -> {
+            String material = materialOf(key);
+            boolean air = material.endsWith(":air") || material.endsWith("cave_air") || material.endsWith("void_air");
+            NativeBlockState state = mock(NativeBlockState.class, withSettings().stubOnly());
+            when(state.key()).thenReturn(key);
+            when(state.materialKey()).thenReturn(material);
+            when(state.isAir()).thenReturn(air);
+            when(state.isSolid()).thenReturn(!air);
+            when(state.isOccluding()).thenReturn(!air);
+            return state;
+        });
+    }
+
+    private static String materialOf(String key) {
+        String trimmed = key.trim().toLowerCase(Locale.ROOT);
+        int properties = trimmed.indexOf('[');
+        String head = properties < 0 ? trimmed : trimmed.substring(0, properties);
+        return head.indexOf(':') < 0 ? "minecraft:" + head : head;
+    }
+
+    private static final class IgnoredPreservation implements PreservationRegistry {
+        @Override
+        public void register(Thread thread) {
+        }
+
+        @Override
+        public void register(ExecutorService service) {
+        }
+
+        @Override
+        public void registerCache(MeteredCache cache) {
+        }
+
+        @Override
+        public void dereference() {
+        }
+    }
+
+    private static final class Statistics {
+        private long checked;
+        private long slack;
+        private int maximumActual;
+        private int maximumReach;
+
+        @Override
+        public String toString() {
+            return "checked=" + checked + " maxActual=" + maximumActual + " maxReach=" + maximumReach
+                    + " meanSlack=" + (checked == 0 ? 0D : (double) slack / checked);
+        }
+    }
+}

core/src/test/java/art/arcane/iris/generation/mantle/PlacementReachTest.java

@@ -0,0 +1,407 @@
+package art.arcane.iris.generation.mantle;
+
+import art.arcane.iris.generation.block.TileData;
+import art.arcane.iris.generation.decoration.IrisStiltSettings;
+import art.arcane.iris.generation.decoration.IrisVacuumSettings;
+import art.arcane.iris.generation.geometry.IrisBlockVector;
+import art.arcane.iris.generation.noise.IrisGeneratorStyle;
+import art.arcane.iris.generation.noise.NoiseStyle;
+import art.arcane.iris.generation.runtime.Engine;
+import art.arcane.iris.generation.runtime.IrisComplex;
+import art.arcane.iris.pack.loading.IrisData;
+import art.arcane.iris.spi.IrisPlatform;
+import art.arcane.iris.spi.IrisPlatforms;
+import art.arcane.iris.spi.PlatformRegistries;
+import art.arcane.iris.structure.object.FloatingObjectFootprint;
+import art.arcane.iris.structure.object.IObjectPlacer;
+import art.arcane.iris.structure.object.IrisAxisRotationClamp;
+import art.arcane.iris.structure.object.IrisObject;
+import art.arcane.iris.structure.object.IrisObjectPlacement;
+import art.arcane.iris.structure.object.IrisObjectPlacementScaleInterpolator;
+import art.arcane.iris.structure.object.IrisObjectRotation;
+import art.arcane.iris.structure.object.IrisObjectScale;
+import art.arcane.iris.structure.object.IrisObjectTranslate;
+import art.arcane.iris.structure.object.ObjectPlaceMode;
+import art.arcane.iris.testsupport.PlatformLeakGuard;
+import art.arcane.volmlib.nativelib.terrain.NativeBlockState;
+import art.arcane.volmlib.util.math.RNG;
+import art.arcane.volmlib.util.stream.ProceduralStream;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.ClassRule;
+import org.junit.Test;
+
+import java.util.List;
+import java.util.Locale;
+import java.util.Map;
+import java.util.Random;
+import java.util.concurrent.ConcurrentHashMap;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+import static org.mockito.ArgumentMatchers.anyBoolean;
+import static org.mockito.ArgumentMatchers.anyString;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
+import static org.mockito.Mockito.withSettings;
+
+public class PlacementReachTest {
+    @ClassRule
+    public static final PlatformLeakGuard PLATFORM_GUARD = PlatformLeakGuard.clean();
+
+    private static final int ORIGIN_X = 1000;
+    private static final int ORIGIN_Y = 90;
+    private static final int ORIGIN_Z = -2000;
+    private static final int GROUND_Y = 64;
+
+    private final Map<String, NativeBlockState> states = new ConcurrentHashMap<>();
+    private IrisData data;
+    private IrisData objectData;
+    private Engine engine;
+
+    @Before
+    public void bindPlatform() {
+        IrisPlatforms.unbind();
+        PlatformRegistries registries = mock(PlatformRegistries.class, withSettings().stubOnly());
+        when(registries.block(anyString())).thenAnswer(invocation -> state(invocation.getArgument(0)));
+        when(registries.blockOrNull(anyString())).thenAnswer(invocation -> state(invocation.getArgument(0)));
+        when(registries.blockOrNull(anyString(), anyBoolean())).thenAnswer(invocation -> state(invocation.getArgument(0)));
+        when(registries.air()).thenAnswer(invocation -> state("minecraft:air"));
+        IrisPlatform platform = mock(IrisPlatform.class, withSettings().stubOnly());
+        when(platform.registries()).thenReturn(registries);
+        IrisPlatforms.bind(platform);
+
+        ProceduralStream<NativeBlockState> rock = mock(ProceduralStream.class, withSettings().stubOnly());
+        IrisComplex complex = mock(IrisComplex.class, withSettings().stubOnly());
+        when(complex.getRockStream()).thenReturn(rock);
+        engine = mock(Engine.class, withSettings().stubOnly());
+        when(engine.getHeight()).thenReturn(256);
+        when(engine.getMinHeight()).thenReturn(0);
+        when(engine.getComplex()).thenReturn(complex);
+        data = mock(IrisData.class, withSettings().stubOnly());
+        when(data.getEngine()).thenReturn(engine);
+        objectData = mock(IrisData.class, withSettings().stubOnly());
+    }
+
+    @After
+    public void unbindPlatform() {
+        IrisPlatforms.unbind();
+    }
+
+    @Test
+    public void halfExtentReachIsTheCenteredFrameNotTheFullWidth() {
+        IrisObject object = singleBlockObject(103, 75, 73);
+        IrisObjectPlacement placement = new IrisObjectPlacement();
+
+        assertEquals(51, PlacementReach.of(object, placement, 1D).horizontal());
+        assertEquals(54, PlacementReach.of(object, placement, 1D).input());
+        assertEquals(51, PlacementReach.of(object, placement.setRotation(IrisObjectRotation.of(0D, 0D, 0D)), 1D).horizontal());
+    }
+
+    @Test
+    public void arbitraryAngleRotationUsesTheRotatedFrame() {
+        IrisObject object = singleBlockObject(21, 5, 21);
+        IrisObjectPlacement placement = new IrisObjectPlacement().setRotation(rotation(new IrisAxisRotationClamp(),
+                new IrisAxisRotationClamp(true, false, 0D, 0D, 45D), new IrisAxisRotationClamp()));
+
+        assertEquals(14, PlacementReach.of(object, placement, 1D).horizontal());
+    }
+
+    @Test
+    public void unionKeepsTheLargestReachAndTheLargestInput() {
+        PlacementReach union = new PlacementReach(10, 2).union(new PlacementReach(4, 12));
+
+        assertEquals(10, union.horizontal());
+        assertEquals(16, union.input());
+        assertEquals(19, union.withReadMargin(9).input());
+        assertEquals(16, union.withReadMargin(1).input());
+    }
+
+    @Test
+    public void scaledSpanBoundsEveryScaledVariant() {
+        Random random = new Random(91L);
+        double[] scales = {0.01D, 0.25D, 0.45D, 0.5D, 0.75D, 0.95D, 1D, 1.3D, 1.5D, 2D, 2.6D, 3.7D, 4D};
+        for (int trial = 0; trial < 120; trial++) {
+            int outside = trial % 3 == 0 ? 1 + random.nextInt(3) : 0;
+            IrisObject object = randomObject(random, outside);
+            PlacementReach.Extent extent = PlacementReach.Extent.of(object);
+            for (double scale : scales) {
+                for (IrisObjectPlacementScaleInterpolator interpolation : List.of(IrisObjectPlacementScaleInterpolator.NONE,
+                        IrisObjectPlacementScaleInterpolator.TRILINEAR)) {
+                    if (interpolation != IrisObjectPlacementScaleInterpolator.NONE && scale > 2D) {
+                        continue;
+                    }
+                    IrisObject scaled = object.scaled(scale, interpolation);
+                    for (double maximum : new double[]{scale, Math.min(IrisObjectScale.MAXIMUM_FACTOR, scale * 1.4D)}) {
+                        assertContains(extent.scaled(maximum), scaled, "scale " + scale + " bounded at " + maximum);
+                        for (double shrink : new double[]{0.45D, 0.8D}) {
+                            assertContains(extent.scaled(maximum).scaled(shrink),
+                                    scaled.scaled(shrink, IrisObjectPlacementScaleInterpolator.NONE),
+                                    "scale " + scale + " shrink " + shrink);
+                        }
+                    }
+                }
+            }
+        }
+    }
+
+    @Test
+    public void runnerWritesAndReadsStayInsideTheReach() {
+        Random random = new Random(1337L);
+        for (int trial = 0; trial < 260; trial++) {
+            IrisObject object = randomObject(random, trial % 5 == 0 ? 2 : 0);
+            object.setLoader(objectData);
+            IrisObjectPlacement placement = randomPlacement(random);
+            PlacementReach reach = PlacementReach.of(object, placement, placement.getMaximumScale(null));
+            for (int seed = 0; seed < 12; seed++) {
+                RNG rng = new RNG((trial * 7919L) + seed);
+                IrisObject variant = placement.getScale() == null ? object : placement.getScale().get(rng, object);
+                RecordingPlacer placer = new RecordingPlacer(engine);
+                variant.place(ORIGIN_X, ORIGIN_Y, ORIGIN_Z, placer, placement, rng, null, null, data);
+                String context = "trial " + trial + " seed " + seed + " mode " + placement.getMode()
+                        + " rotation " + placement.getRotation() + " translate " + placement.getTranslate()
+                        + " scale " + placement.getScale() + " warp " + placement.getWarp().getMultiplier();
+                assertTrue(context + " writes " + placer.writeReach + " > " + reach.horizontal(),
+                        placer.writeReach <= reach.horizontal());
+                assertTrue(context + " reads " + placer.readReach + " > " + reach.input(),
+                        placer.readReach <= reach.input());
+            }
+        }
+    }
+
+    @Test
+    public void anchoredReachCoversTheFloatingFootprintAnchor() {
+        Random random = new Random(7L);
+        for (int trial = 0; trial < 80; trial++) {
+            IrisObject object = randomObject(random, trial % 4 == 0 ? 1 : 0);
+            PlacementReach reach = PlacementReach.anchored(PlacementReach.Extent.of(object), new IrisObjectPlacement());
+            FloatingObjectFootprint footprint = FloatingObjectFootprint.compute(object);
+            for (IrisObjectRotation rotation : List.of(IrisObjectRotation.of(0D, 0D, 0D),
+                    IrisObjectRotation.xFlip180WithY(0D), IrisObjectRotation.xFlip180WithY(90D),
+                    IrisObjectRotation.xFlip180WithY(180D), IrisObjectRotation.xFlip180WithY(270D))) {
+                IrisBlockVector anchor = rotation.rotate(new IrisBlockVector(footprint.getTallestKx(), 0, footprint.getTallestKz()), 0, 0, 0);
+                object.getBlocks().forEach((position, state) -> {
+                    IrisBlockVector rotated = rotation.rotate(position, 0, 0, 0);
+                    assertTrue(Math.abs((int) Math.round(rotated.getX()) - anchor.getBlockX()) <= reach.horizontal());
+                    assertTrue(Math.abs((int) Math.round(rotated.getZ()) - anchor.getBlockZ()) <= reach.horizontal());
+                });
+            }
+        }
+    }
+
+    private IrisObjectPlacement randomPlacement(Random random) {
+        IrisObjectPlacement placement = new IrisObjectPlacement();
+        placement.setRotation(randomRotation(random));
+        if (random.nextInt(3) > 0) {
+            placement.setTranslate(new IrisObjectTranslate()
+                    .setX(random.nextInt(41) - 20)
+                    .setY(random.nextInt(21) - 10)
+                    .setZ(random.nextInt(41) - 20));
+        }
+        if (random.nextInt(3) == 0) {
+            placement.setWarp(new IrisGeneratorStyle(NoiseStyle.SIMPLEX).setMultiplier(1D + random.nextInt(9)));
+        }
+        List<ObjectPlaceMode> modes = List.of(ObjectPlaceMode.CENTER_HEIGHT, ObjectPlaceMode.STILT, ObjectPlaceMode.FAST_STILT,
+                ObjectPlaceMode.CENTER_STILT, ObjectPlaceMode.ERODE_STILT, ObjectPlaceMode.ORGANIC_STILT, ObjectPlaceMode.CEILING_HANG,
+                ObjectPlaceMode.VACUUM, ObjectPlaceMode.VACUUM_HIGH, ObjectPlaceMode.VACUUM_FAST, ObjectPlaceMode.VACUUM_ORGANIC,
+                ObjectPlaceMode.VACUUM_WAVY, ObjectPlaceMode.STRUCTURE_PIECE);
+        placement.setMode(modes.get(random.nextInt(modes.size())));
+        if (random.nextInt(4) == 0) {
+            placement.setVacuumSettings(new IrisVacuumSettings().setRadius(1 + random.nextInt(16)));
+        }
+        if (random.nextInt(4) == 0) {
+            placement.setStiltSettings(new IrisStiltSettings());
+        }
+        placement.setBore(random.nextInt(4) == 0);
+        placement.setBoreExtendMaxY(random.nextInt(3));
+        placement.setSnow(random.nextInt(4) == 0 ? 0.6D : 0D);
+        placement.setSurfaceSupportBuffer(random.nextInt(5));
+        switch (random.nextInt(5)) {
+            case 0 -> placement.setScale(new IrisObjectScale().setSize(0.3D + (random.nextDouble() * 1.6D)));
+            case 1 -> placement.setScale(new IrisObjectScale().setMinimumScale(0.5D).setMaximumScale(2.3D)
+                    .setVariations(5).setInterpolation(IrisObjectPlacementScaleInterpolator.TRILINEAR));
+            case 2 -> placement.setScale(new IrisObjectScale().setMinimumScale(0.4D).setMaximumScale(0.9D).setVariations(3));
+            default -> {
+            }
+        }
+        return placement;
+    }
+
+    private static IrisObjectRotation randomRotation(Random random) {
+        return switch (random.nextInt(9)) {
+            case 0 -> new IrisObjectRotation();
+            case 1 -> IrisObjectRotation.of(0D, 0D, 0D);
+            case 2 -> rotation(new IrisAxisRotationClamp(), new IrisAxisRotationClamp(true, false, 0D, 0D, 45D), new IrisAxisRotationClamp());
+            case 3 -> rotation(new IrisAxisRotationClamp(), new IrisAxisRotationClamp(true, false, 0D, 0D, 0D), new IrisAxisRotationClamp());
+            case 4 -> IrisObjectRotation.of(90D, 0D, 0D);
+            case 5 -> rotation(new IrisAxisRotationClamp(true, false, 0D, 0D, 90D),
+                    new IrisAxisRotationClamp(true, false, 0D, 0D, 90D), new IrisAxisRotationClamp(true, false, 0D, 0D, 90D));
+            case 6 -> rotation(new IrisAxisRotationClamp(true, false, 0D, 0D, 0D),
+                    new IrisAxisRotationClamp(true, false, 0D, 0D, 0D), new IrisAxisRotationClamp(true, false, 0D, 0D, 30D));
+            case 7 -> IrisObjectRotation.of(30D, 135D, 0D);
+            default -> rotation(new IrisAxisRotationClamp(), new IrisAxisRotationClamp(true, false, 20D, 110D, 15D),
+                    new IrisAxisRotationClamp(true, true, 180D, 180D, 0D));
+        };
+    }
+
+    private IrisObject randomObject(Random random, int outside) {
+        int width = 1 + random.nextInt(18);
+        int height = 1 + random.nextInt(14);
+        int depth = 1 + random.nextInt(18);
+        IrisObject object = new IrisObject(width, height, depth);
+        int count = 1 + random.nextInt(Math.max(1, (width * height * depth) / 3));
+        for (int index = 0; index < count; index++) {
+            int x = random.nextInt(width) - (width / 2);
+            int y = random.nextInt(height) - (height / 2);
+            int z = random.nextInt(depth) - (depth / 2);
+            object.getBlocks().put(new IrisBlockVector(x, y, z), state(random.nextInt(5) == 0 ? "minecraft:oak_leaves" : "minecraft:stone"));
+        }
+        for (int index = 0; index < outside; index++) {
+            int x = random.nextInt(width + 10) - ((width + 10) / 2);
+            int y = random.nextInt(height + 6) - ((height + 6) / 2);
+            int z = random.nextInt(depth + 10) - ((depth + 10) / 2);
+            object.getBlocks().put(new IrisBlockVector(x, y, z), state("minecraft:stone"));
+        }
+        return object;
+    }
+
+    private IrisObject singleBlockObject(int width, int height, int depth) {
+        IrisObject object = new IrisObject(width, height, depth);
+        object.getBlocks().put(new IrisBlockVector(0, 0, 0), state("minecraft:stone"));
+        return object;
+    }
+
+    private static void assertContains(PlacementReach.Extent extent, IrisObject object, String context) {
+        object.getBlocks().forEach((position, state) -> {
+            assertTrue(context + " x " + position.getBlockX() + " outside " + extent.x(),
+                    position.getBlockX() >= extent.x().minimum() && position.getBlockX() <= extent.x().maximum());
+            assertTrue(context + " y " + position.getBlockY() + " outside " + extent.y(),
+                    position.getBlockY() >= extent.y().minimum() && position.getBlockY() <= extent.y().maximum());
+            assertTrue(context + " z " + position.getBlockZ() + " outside " + extent.z(),
+                    position.getBlockZ() >= extent.z().minimum() && position.getBlockZ() <= extent.z().maximum());
+        });
+        int centerX = object.getCenter().getBlockX();
+        int centerZ = object.getCenter().getBlockZ();
+        assertTrue(context + " frame x", -centerX >= extent.x().minimum() && object.getW() - 1 - centerX <= extent.x().maximum());
+        assertTrue(context + " frame z", -centerZ >= extent.z().minimum() && object.getD() - 1 - centerZ <= extent.z().maximum());
+    }
+
+    private static IrisObjectRotation rotation(IrisAxisRotationClamp x, IrisAxisRotationClamp y, IrisAxisRotationClamp z) {
+        IrisObjectRotation rotation = new IrisObjectRotation();
+        rotation.setEnabled(true);
+        rotation.setXAxis(x);
+        rotation.setYAxis(y);
+        rotation.setZAxis(z);
+        return rotation;
+    }
+
+    private NativeBlockState state(String key) {
+        return states.computeIfAbsent(key, ignored -> {
+            String material = key.toLowerCase(Locale.ROOT);
+            boolean air = material.endsWith("air");
+            NativeBlockState state = mock(NativeBlockState.class, withSettings().stubOnly());
+            when(state.key()).thenReturn(key);
+            when(state.materialKey()).thenReturn(material);
+            when(state.isAir()).thenReturn(air);
+            when(state.isSolid()).thenReturn(!air);
+            when(state.isOccluding()).thenReturn(!air);
+            return state;
+        });
+    }
+
+    private static final class RecordingPlacer implements IObjectPlacer {
+        private final Engine engine;
+        private int writeReach;
+        private int readReach;
+
+        private RecordingPlacer(Engine engine) {
+            this.engine = engine;
+        }
+
+        private void write(int x, int z) {
+            writeReach = Math.max(writeReach, Math.max(Math.abs(x - ORIGIN_X), Math.abs(z - ORIGIN_Z)));
+            read(x, z);
+        }
+
+        private void read(int x, int z) {
+            readReach = Math.max(readReach, Math.max(Math.abs(x - ORIGIN_X), Math.abs(z - ORIGIN_Z)));
+        }
+
+        @Override
+        public int getHighest(int x, int z, IrisData data) {
+            read(x, z);
+            return GROUND_Y;
+        }
+
+        @Override
+        public int getHighest(int x, int z, IrisData data, boolean ignoreFluid) {
+            read(x, z);
+            return GROUND_Y;
+        }
+
+        @Override
+        public void set(int x, int y, int z, NativeBlockState d) {
+            write(x, z);
+        }
+
+        @Override
+        public NativeBlockState get(int x, int y, int z) {
+            read(x, z);
+            return null;
+        }
+
+        @Override
+        public boolean isPreventingDecay() {
+            return false;
+        }
+
+        @Override
+        public boolean isCarved(int x, int y, int z) {
+            read(x, z);
+            return false;
+        }
+
+        @Override
+        public boolean isSolid(int x, int y, int z) {
+            read(x, z);
+            return y < GROUND_Y;
+        }
+
+        @Override
+        public boolean isUnderwater(int x, int z) {
+            read(x, z);
+            return false;
+        }
+
+        @Override
+        public int getFluidHeight() {
+            return GROUND_Y - 1;
+        }
+
+        @Override
+        public boolean isDebugSmartBore() {
+            return false;
+        }
+
+        @Override
+        public void setTile(int xx, int yy, int zz, TileData tile) {
+            write(xx, zz);
+        }
+
+        @Override
+        public <T> void setData(int xx, int yy, int zz, T data) {
+            write(xx, zz);
+        }
+
+        @Override
+        public <T> T getData(int xx, int yy, int zz, Class<T> t) {
+            read(xx, zz);
+            return null;
+        }
+
+        @Override
+        public Engine getEngine() {
+            return engine;
+        }
+    }
+}