Restored branch tip decorators

- Branch tip accents occupy the first free outward cell beyond their leaf cluster
- Existing wood leaves and accents retain their positions
- Tests cover opposite branch directions and repeated placement

core/src/main/java/art/arcane/iris/engine/object/tree/TreeDecoratorApplier.java

@@ -67,11 +67,24 @@ public final class TreeDecoratorApplier {
             if (rng.nextDouble() > dec.getChance()) {
                 continue;
             }
-            if (canvas.has(e[0], e[1], e[2])) {
+            int dx = e[0] - e[3];
+            int dz = e[2] - e[4];
+            boolean alongX = Math.abs(dx) >= Math.abs(dz);
+            int stepX = alongX ? (dx >= 0 ? 1 : -1) : 0;
+            int stepZ = alongX ? 0 : (dz >= 0 ? 1 : -1);
+            int x = e[0] + stepX;
+            int z = e[2] + stepZ;
+            TreeBlockCanvas.Cell cell = canvas.get(x, e[1], z);
+            while (cell != null && cell.role() != TreeBlockCanvas.Role.DECORATOR) {
+                x += stepX;
+                z += stepZ;
+                cell = canvas.get(x, e[1], z);
+            }
+            if (cell != null) {
                 continue;
             }
             String facing = dec.isAxisAware() ? facingAway(e[3], e[4], e[0], e[2]) : null;
-            canvas.setDecor(e[0], e[1], e[2], idx, facing);
+            canvas.setDecor(x, e[1], z, idx, facing);
         }
     }
 

core/src/test/java/art/arcane/iris/engine/object/tree/TreeDecoratorApplierTest.java

@@ -0,0 +1,45 @@
+package art.arcane.iris.engine.object.tree;
+
+import art.arcane.iris.engine.object.IrisProceduralTree;
+import art.arcane.iris.engine.object.IrisTreeDecorator;
+import art.arcane.iris.engine.object.IrisTreeDecoratorTarget;
+import art.arcane.volmlib.util.collection.KList;
+import org.junit.Test;
+
+import java.util.List;
+
+import static org.junit.Assert.assertEquals;
+
+public class TreeDecoratorApplierTest {
+    @Test
+    public void branchTipsExtendOutwardThroughLeavesWithoutReplacingWood() {
+        TreeBlockCanvas canvas = new TreeBlockCanvas();
+        for (int x = -3; x <= 3; x++) {
+            canvas.setTrunk(x, 4, 0, TreeBlockCanvas.Role.TRUNK, TreeBlockCanvas.Axis.X);
+        }
+        canvas.setLeaf(-4, 4, 0, TreeBlockCanvas.Role.LEAF);
+        canvas.setLeaf(4, 4, 0, TreeBlockCanvas.Role.LEAF);
+        IrisTreeDecorator decorator = new IrisTreeDecorator()
+                .setTarget(IrisTreeDecoratorTarget.BRANCH_TIP)
+                .setBlock("minecraft:shroomlight")
+                .setChance(1D)
+                .setAxisAware(true);
+        IrisProceduralTree tree = new IrisProceduralTree();
+        tree.setDecorators(new KList<>(decorator));
+        List<int[]> endpoints = List.of(new int[]{-3, 4, 0, 0, 0}, new int[]{3, 4, 0, 0, 0});
+
+        TreeDecoratorApplier.apply(canvas, tree, 4321L, endpoints);
+
+        assertEquals(TreeBlockCanvas.Role.DECORATOR, canvas.get(-5, 4, 0).role());
+        assertEquals("west", canvas.get(-5, 4, 0).facing());
+        assertEquals(TreeBlockCanvas.Role.DECORATOR, canvas.get(5, 4, 0).role());
+        assertEquals("east", canvas.get(5, 4, 0).facing());
+        assertEquals(7, canvas.getTrunk().size());
+        assertEquals(2, canvas.getLeaf().size());
+        assertEquals(11, canvas.getCells().size());
+
+        TreeDecoratorApplier.apply(canvas, tree, 4321L, endpoints);
+
+        assertEquals(11, canvas.getCells().size());
+    }
+}