From d55b652b0edb2341ce2cd2ada6627fe1c76392e1 Mon Sep 17 00:00:00 2001
From: Yi Zhang <zhangyi@microsoft.com>
Date: Fri, 24 Mar 2023 15:49:33 -0700
Subject: [PATCH 1/2] avoid extra loops when terrain does not exist

---
 src/symbol/placement.ts | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/src/symbol/placement.ts b/src/symbol/placement.ts
index 0e86e93e93e..03f4f6c8a4f 100644
--- a/src/symbol/placement.ts
+++ b/src/symbol/placement.ts
@@ -460,6 +460,9 @@ export class Placement {
             bucket.deserializeCollisionBoxes(collisionBoxArray);
         }
 
+        const tileID = this.retainedQueryData[bucket.bucketInstanceId].tileID;
+        const getElevation = this.terrain ? (x: number, y: number) => this.terrain.getElevation(tileID, x, y) : null;
+
         const placeSymbol = (symbolInstance: SymbolInstance, collisionArrays: CollisionArrays) => {
             if (seenCrossTileIDs[symbolInstance.crossTileID]) return;
             if (holdingForFade) {
@@ -494,11 +497,13 @@ export class Placement {
             }
 
             // update elevation of collisionArrays
-            const tileID = this.retainedQueryData[bucket.bucketInstanceId].tileID;
-            const getElevation = this.terrain ? (x: number, y: number) => this.terrain.getElevation(tileID, x, y) : null;
-            for (const boxType of ['textBox', 'verticalTextBox', 'iconBox', 'verticalIconBox']) {
-                const box = collisionArrays[boxType];
-                if (box) box.elevation = getElevation ? getElevation(box.anchorPointX, box.anchorPointY) : 0;
+            if (getElevation) {
+                for (const boxType of ['textBox', 'verticalTextBox', 'iconBox', 'verticalIconBox']) {
+                    const box = collisionArrays[boxType];
+                    if (box) {
+                        box.elevation = getElevation(box.anchorPointX, box.anchorPointY);
+                    }
+                }
             }
 
             const textBox = collisionArrays.textBox;

From ccba4a1a8460c95dd40bb969fb0a05b0b8d8eaa0 Mon Sep 17 00:00:00 2001
From: "Yi Zhang (BING)" <zhangyi@microsoft.com>
Date: Tue, 28 Mar 2023 09:13:47 -0700
Subject: [PATCH 2/2] removed the block according to PR feedback

---
 src/symbol/placement.ts | 10 ----------
 1 file changed, 10 deletions(-)

diff --git a/src/symbol/placement.ts b/src/symbol/placement.ts
index 03f4f6c8a4f..62ba3ef3c95 100644
--- a/src/symbol/placement.ts
+++ b/src/symbol/placement.ts
@@ -496,16 +496,6 @@ export class Placement {
                 verticalTextFeatureIndex = collisionArrays.verticalTextFeatureIndex;
             }
 
-            // update elevation of collisionArrays
-            if (getElevation) {
-                for (const boxType of ['textBox', 'verticalTextBox', 'iconBox', 'verticalIconBox']) {
-                    const box = collisionArrays[boxType];
-                    if (box) {
-                        box.elevation = getElevation(box.anchorPointX, box.anchorPointY);
-                    }
-                }
-            }
-
             const textBox = collisionArrays.textBox;
             if (textBox) {