From 6199f2a0a2274927bab0f3d452dd9f7cd8610ddf Mon Sep 17 00:00:00 2001
From: Mirko Pecora <mi.pecora@reply.it>
Date: Fri, 2 Oct 2026 12:39:18 +0200
Subject: [PATCH] feat(bounds-margin): update boundsMargin to support per-side
 tuple

---
 src/core/dom-renderer/domRendererTypes.ts |  9 +++---
 src/core/dom-renderer/domRendererUtils.ts | 37 ++++++++---------------
 2 files changed, 17 insertions(+), 29 deletions(-)

diff --git a/src/core/dom-renderer/domRendererTypes.ts b/src/core/dom-renderer/domRendererTypes.ts
index 8565ea5e..5cb71027 100644
--- a/src/core/dom-renderer/domRendererTypes.ts
+++ b/src/core/dom-renderer/domRendererTypes.ts
@@ -12,7 +12,7 @@ import {
 /** Based on {@link lng.CoreRenderer} */
 export interface IRendererCoreRenderer {
   mode: 'canvas' | 'webgl' | undefined;
-  boundsMargin?: number;
+  boundsMargin?: number | [number, number, number, number];
 }
 /** Based on {@link lng.TrFontManager} */
 export interface IRendererFontManager {
@@ -148,9 +148,8 @@ export interface DomRendererMainSettings {
    * Preload margin around the viewport, in logical pixels (default: 200)
    *
    * @remarks
-   * A single number applied to all sides. The `[top, right, bottom, left]`
-   * array form was dropped in renderer 1.8; it is still tolerated at runtime
-   * (the largest edge wins, with a warning) but should be replaced.
+   * A single number applied to all sides, or a per-side
+   * `[top, right, bottom, left]` tuple.
    */
-  boundsMargin?: number;
+  boundsMargin?: number | [number, number, number, number];
 }
diff --git a/src/core/dom-renderer/domRendererUtils.ts b/src/core/dom-renderer/domRendererUtils.ts
index 07ca5d45..c2c196a7 100644
--- a/src/core/dom-renderer/domRendererUtils.ts
+++ b/src/core/dom-renderer/domRendererUtils.ts
@@ -222,30 +222,19 @@ export function nodeHasTextureSource(node: DOMNode): boolean {
 }
 
 /**
- * Coerce a `boundsMargin` value to the scalar the renderer takes since 1.8.
- *
- * @remarks
- * The `[top, right, bottom, left]` array form was dropped in renderer 1.8. An
- * untyped app upgrading from 1.7 can still pass it, so mirror the WebGL
- * renderer and take the widest edge rather than letting the margin arithmetic
- * go wrong.
+ * Normalize a `boundsMargin` value (scalar or per-side tuple) into a
+ * `[top, right, bottom, left]` tuple.
  */
 export function normalizeBoundsMargin(
   margin: number | number[] | null | undefined,
-): number {
-  if (margin == null) return 0;
-  if (Array.isArray(margin) === false) return margin as number;
-  const arr = margin as number[];
-  let max = 0;
-  for (let i = 0; i < arr.length; i++) {
-    if (arr[i]! > max) {
-      max = arr[i]!;
-    }
+): [number, number, number, number] {
+  if (margin == null) return [0, 0, 0, 0];
+  if (Array.isArray(margin) === false) {
+    const m = (margin as number) || 0;
+    return [m, m, m, m];
   }
-  console.warn(
-    `boundsMargin array form is no longer supported, using the largest edge value: ${max}`,
-  );
-  return max;
+  const arr = margin as number[];
+  return [arr[0] || 0, arr[1] || 0, arr[2] || 0, arr[3] || 0];
 }
 
 export function computeRenderStateForNode(
@@ -273,10 +262,10 @@ export function computeRenderStateForNode(
   const right = left + width;
   const bottom = top + height;
 
-  const expandedLeft = rootLeft - margin;
-  const expandedTop = rootTop - margin;
-  const expandedRight = rootRight + margin;
-  const expandedBottom = rootBottom + margin;
+  const expandedLeft = rootLeft - margin[3];
+  const expandedTop = rootTop - margin[0];
+  const expandedRight = rootRight + margin[1];
+  const expandedBottom = rootBottom + margin[2];
 
   const intersectsBounds =
     right >= expandedLeft &&